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Sample records for basal ganglia thalamus

  1. Basal ganglia - thalamus and the crowning enigma

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    Marianela eGarcia-Munoz

    2015-11-01

    Full Text Available When Hubel (1982 referred to layer 1 of primary visual cortex as …a ‘crowning mystery’ to keep area-17 physiologists busy for years to come... he could have been talking about any cortical area. In the 80’s and 90’s there were no methods to examine this neuropile on the surface of the cortex: a tangled web of axons and dendrites from a variety of different places with unknown specificities and doubtful connections to the cortical output neurons some hundreds of microns below. Recently, three changes have made the crowning enigma less of an impossible mission: the clear presence of neurons in layer 1 (L1, the active conduction of voltage along apical dendrites and optogenetic methods that might allow us to look at one source of input at a time. For all of those reasons alone, it seems it is time to take seriously the function of L1. The functional properties of this layer will need to wait for more experiments but already L1 cells are GAD67 positive, i.e., inhibitory! They could reverse the sign of the thalamic glutamate (GLU input for the entire cortex. It is at least possible that in the near future normal activity of individual sources of L1 could be detected using genetic tools. We are at the outset of important times in the exploration of thalamic functions and perhaps the solution to the crowning enigma is within sight. Our review looks forward to that solution from the solid basis of the anatomy of the basal ganglia output to motor thalamus. We will focus on L1, its afferents, intrinsic neurons and its influence on responses of pyramidal neurons in layers 2/3 and 5. Since L1 is present in the whole cortex we will provide a general overview considering evidence mainly from the somatosensory cortex before focusing on motor cortex.

  2. Correlation transfer from basal ganglia to thalamus in Parkinson's disease

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    Pamela eReitsma

    2011-12-01

    Full Text Available Spike trains from neurons in the basal ganglia of parkinsonian primatesshow increased pairwise correlations, oscillatory activity, and burstrate compared to those from neurons recorded during normal brainactivity. However, it is not known how these changes affect the behaviorof downstream thalamic neurons. To understand how patterns ofbasal ganglia population activity may affect thalamic spike statistics,we study pairs of model thalamocortical (TC relay neurons receivingcorrelated inhibitory input from the internal segment of the globus pallidus(GPi, a primary output nucleus of the basal ganglia. We observethat the strength of correlations of TC neuron spike trains increaseswith the GPi correlation level, and bursty firing patterns such as thoseseen in the parkinsonian GPi allow for stronger transfer of correlationsthan do firing patterns found under normal conditions. We also showthat the T-current in the TC neurons does not significantly affect correlationtransfer, despite its pronounced effects on spiking. Oscillatoryfiring patterns in GPi are shown to affect the timescale at which correlationsare best transferred through the system. To explain this lastresult, we analytically compute the spike count correlation coefficientfor oscillatory cases in a reduced point process model. Our analysisindicates that the dependence of the timescale of correlation transfer isrobust to different levels of input spike and rate correlations and arisesdue to differences in instantaneous spike correlations, even when thelong timescale rhythmic modulations of neurons are identical. Overall,these results show that parkinsonian firing patterns in GPi do affectthe transfer of correlations to the thalamus.

  3. Unilateral germinomas involving the basal ganglia and thalamus.

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    Kobayashi, T; Kageyama, N; Kida, Y; Yoshida, J; Shibuya, N; Okamura, K

    1981-07-01

    Clinical characteristics of six cases of germinoma involving a unilateral basal ganglion and thalamus are summarized. The incidence was estimated as 10% of all intracranial germinomas. The average age at the onset was 10.5 years. The sex incidence showed a male dominance. The clinical course was slowly progressive, and the average duration between onset and diagnosis was 2 years 5 months. Common symptoms and signs were hemiparesis in all cases, fever of unknown origin and eye symptoms in most, mental deterioration and psychiatric signs in three, and convulsions, pubertas praecox, and diabetes insipidus in two. Signs of increased intracranial pressure were found in only two cases in the later state of the disease. Early diagnosis is difficult because of nonspecific symptomatology and slow progression. Carotid angiography and pneumoencephalography showed abnormal findings compatible with basal ganglia and thalamic tumors, but not specific to germinoma. Ipsilateral cortical atrophy and ventricular dilatation might be significant findings. Radioisotope scanning was useful. Computerized tomography scans were the best method of detecting the location and nature of this tumor, and repeat scans showed response to radiation therapy. PMID:7241216

  4. MR imaging study of tumors originating in the basal ganglia and thalamus in children

    International Nuclear Information System (INIS)

    Objective: To study and compare the clinical and MR imaging characteristics of tumors originating in the basal ganglia and thalamus in children. Analysis was focussed on the relationship of the sex, location and the signal characteristics of the tumors. Methods: MR imaging studies of 36 children (23 boys and 13 girls; ranging in age from 3-15 years; mean age, 10.7 years) with the tumors arising from the basal ganglia and thalamus were reviewed retrospectively. The tumors included 15 astrocytomas, 8 glioblastomas, 9 germinoma, 2 malignant teratomas and 2 gangliocytomas. All had surgery, with pathologic confirmation. Results: In 23 gliomas, 1 was located in basal ganglia and 22 in thalamus. There was a slight male predilection. All germinomas and malignant teratomas were male in this group. In germinoma and malignant teratoma group, 2 germinomas and one malignant teratoma were in thalamus, the others were in basal ganglia. Two gangliocytomas were female and located in thalamus. Conclusion: The tumors originating in the basal ganglia and thalamus in children have sex, located in thalamus. Conclusion: The tumors originating in the basal ganglia and thalamus in children have sex, location and imaging characteristics. Therefore, it is possible to make preoperative diagnosis using CT or MR

  5. Massive calcification in basal ganglia, thalamus and cerebellum caused by postoperative hypoparathyroidism

    International Nuclear Information System (INIS)

    The depicted case is of a 65 year old woman, who was admitted to hospital with complaints of excess sweating, dizziness and loss of consciousness. Symptomatic epilepsy was established after examination from a neurologist. A CT scan showed hyperdense symmetrical striation of the hemisphere of the small brain (parasagittal); symmetrical double-sided calcifications in the caudate nucleus, globus pallidus, thalamus and medial to the capsula interna; snake-like calcifications of the sulcus (occipital, parasagittai). Paraclinical tests have found hypocalcemia and hypoparathyroidism. Past illnesses: resection of the thyroid due to a nodose struma 20 years before. Key words: Calcifications in Basal Ganglia. Calcifications in the Cerebrum. Hypoparathyroidism

  6. Creation of computerized 3D MRI-integrated atlases of the human basal ganglia and thalamus

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    Abbas F. Sadikot

    2011-09-01

    Full Text Available Functional brain imaging and neurosurgery in subcortical areas often requires visualization of brain nuclei beyond the resolution of current Magnetic Resonance Imaging (MRI methods. We present techniques used to create: 1 a lower resolution 3D atlas, based on the Schaltenbrand and Wahren print atlas, which was integrated into a stereotactic neurosurgery planning and visualization platform (VIPER; and 2 a higher resolution 3D atlas derived from a single set of manually segmented histological slices containing nuclei of the basal ganglia, thalamus, basal forebrain and medial temporal lobe. Both atlases were integrated to a canonical MRI (Colin27 from a young male participant by manually identifying homologous landmarks. The lower resolution atlas was then warped to fit the MRI based on the identified landmarks. A pseudo-MRI representation of the high-resolution atlas was created, and a nonlinear transformation was calculated in order to match the atlas to the template MRI. The atlas can then be warped to match the anatomy of Parkinson’s disease surgical candidates by using 3D automated nonlinear deformation methods. By way of functional validation of the atlas, the location of the sensory thalamus was correlated with stereotactic intraoperative physiological data. The position of subthalamic electrode positions in patients with Parkinson’s disease was also evaluated in the atlas-integrated MRI space. Finally, probabilistic maps of subthalamic stimulation electrodes were developed, in order to allow group analysis of the location of contacts associated with the best motor outcomes. We have therefore developed, and are continuing to validate, a high-resolution computerized MRI-integrated 3D histological atlas, which is useful in functional neurosurgery, and for functional and anatomical studies of the human basal ganglia, thalamus and basal forebrain.

  7. Proton MR spectroscopic imaging of basal ganglia and thalamus in neurofibromatosis type 1: correlation with T2 hyperintensities

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    Barbier, Charlotte; Barantin, Laurent [CHRU and Tours University, Department of Neuroradiology, Tours (France); Chabernaud, Camille [CHRU and Tours University et INSERM U930, Department of Pediatric Neurology, Tours (France); Bertrand, Philippe [CHRU and Tours University, Department of Radiology, Tours (France); Sembely, Catherine; Sirinelli, Dominique [CHRU and Tours University, Department of Pediatric Radiology, Tours (France); Castelnau, Pierre [CHRU and Tours University et INSERM U930, Department of Pediatric Neurology, Tours (France); CHRU and Tours University et INSERM U930, Tours (France); Neurologie Pediatrique and INSERM U930, Hopital d' Enfants Gatien de Clocheville, Tours cedex 09 (France); Cottier, Jean-Philippe [CHRU and Tours University, Department of Neuroradiology, Tours (France); CHRU and Tours University et INSERM U930, Tours (France)

    2011-02-15

    Neurofibromatosis type 1 (NF1) is frequently associated with hyperintense lesions on T2-weighted images called ''unidentified bright objects'' (UBO). To better characterize the functional significance of UBO, we investigate the basal ganglia and thalamus using spectroscopic imaging in children with NF1 and compare the results to anomalies observed on T2-weighted images. Magnetic resonance (MR) data of 25 children with NF1 were analyzed. On the basis of T2-weighted images analysis, two groups were identified: one with normal MR imaging (UBO- group; n = 10) and one with UBO (UBO+ group; n = 15). Within the UBO+ group, a subpopulation of patients (n = 5) only had lesions of the basal ganglia. We analyzed herein seven regions of interest (ROIs) for each side: caudate nucleus, capsulo-lenticular region, lateral and posterior thalamus, thalamus (lateral and posterior voxels combined), putamen, and striatum. For each ROI, a spectrum of the metabolites and their ratio was obtained. Patients with abnormalities on T2-weighted images had significantly lower NAA/Cr, NAA/Cho, and NAA/mI ratios in the lateral right thalamus compared with patients with normal T2. These abnormal spectroscopic findings were not observed in capsulo-lenticular regions that had UBO but in the thalamus region that was devoid of UBO. Multivoxel spectroscopic imaging using short-time echo showed spectroscopic abnormalities in the right thalamus of NF1 patients harboring UBO, which were mainly located in the basal ganglia. This finding could reflect the anatomical and functional interactions of these regions. (orig.)

  8. The Differential Effects of Thalamus and Basal Ganglia on Facial Emotion Recognition

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    Cheung, Crystal C. Y.; Lee, Tatia M. C.; Yip, James T. H.; King, Kristin E.; Li, Leonard S. W.

    2006-01-01

    This study examined if subcortical stroke was associated with impaired facial emotion recognition. Furthermore, the lateralization of the impairment and the differential profiles of facial emotion recognition deficits with localized thalamic or basal ganglia damage were also studied. Thirty-eight patients with subcortical strokes and 19 matched…

  9. Analysis of grey matter in thalamus and basal ganglia based on EEG α3/α2 frequency ratio reveals specific changes in subjects with mild cognitive impairment

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    Davide V Moretti

    2012-12-01

    Full Text Available GM (grey matter changes of thalamus and basal ganglia have been demonstrated to be involved in AD (Alzheimer's disease. Moreover, the increase of a specific EEG (electroencephalogram marker, α3/α2, have been associated with AD-converters subjects with MCI (mild cognitive impairment. To study the association of prognostic EEG markers with specific GM changes of thalamus and basal ganglia in subjects with MCI to detect biomarkers (morpho-physiological early predictive of AD and non-AD dementia. Seventy-four adult subjects with MCI underwent EEG recording and high-resolution 3D MRI (three-dimensional magnetic resonance imaging. The α3/α2 ratio was computed for each subject. Three groups were obtained according to increasing tertile values of α3/α2 ratio. GM density differences between groups were investigated using a VBM (voxel-based morphometry technique. Subjects with higher α3/α2 ratios when compared with subjects with lower and middle α3/α2 ratios showed minor atrophy in the ventral stream of basal ganglia (head of caudate nuclei and accumbens nuclei bilaterally and of the pulvinar nuclei in the thalamus; The integrated analysis of EEG and morpho-structural markers could be useful in the comprehension of anatomo-physiological underpinning of the MCI entity.

  10. Striatal plasticity and basal ganglia circuit function

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    Kreitzer, Anatol C.; Malenka, Robert C.

    2008-01-01

    The dorsal striatum, which consists of the caudate and putamen, is the gateway to the basal ganglia. It receives convergent excitatory afferents from cortex and thalamus and forms the origin of the direct and indirect pathways—distinct basal ganglia circuits involved in motor control. It is also a major site of activity-dependent synaptic plasticity. Striatal plasticity alters the transfer of information throughout basal ganglia circuits and may represent a key neural substrate for adaptive m...

  11. Striatal plasticity and basal ganglia circuit function.

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    Kreitzer, Anatol C; Malenka, Robert C

    2008-11-26

    The dorsal striatum, which consists of the caudate and putamen, is the gateway to the basal ganglia. It receives convergent excitatory afferents from cortex and thalamus and forms the origin of the direct and indirect pathways, which are distinct basal ganglia circuits involved in motor control. It is also a major site of activity-dependent synaptic plasticity. Striatal plasticity alters the transfer of information throughout basal ganglia circuits and may represent a key neural substrate for adaptive motor control and procedural memory. Here, we review current understanding of synaptic plasticity in the striatum and its role in the physiology and pathophysiology of basal ganglia function. PMID:19038213

  12. Positron emission tomography and basal ganglia functions

    International Nuclear Information System (INIS)

    With the advent of positron emission tomography (PET), studies on the human brain function and pathophysiology of brain damage have been extremely progressed. It is well-known that the basal ganglia plays an important role as one of the central nervous system involved in exercise regulation. More recently, the potential involvement of the basal ganglia in psychological processes, such as cognitive function, has been pointed out, receiving much attention. In spite of such a lot of studies, however, basal ganglia function remains unclear. This paper describes the relationships between PET findings and basal ganglia function. PET findings are discussed in relation to brain energy metabolism and striatal dopamine function. Pathophysiology of the basal ganglia are described in terms of the following diseases: Parkinson's disease, Parkinson's syndrome, progressive supranuclear palsy, Huntington's disease, and dystonia. Physiological backgrounds of the basal ganglia for PET images are also referred to. (N.K.) 75 refs

  13. The basal ganglia communicate with the cerebellum.

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    Bostan, Andreea C; Dum, Richard P; Strick, Peter L

    2010-05-01

    The basal ganglia and cerebellum are major subcortical structures that influence not only movement, but putatively also cognition and affect. Both structures receive input from and send output to the cerebral cortex. Thus, the basal ganglia and cerebellum form multisynaptic loops with the cerebral cortex. Basal ganglia and cerebellar loops have been assumed to be anatomically separate and to perform distinct functional operations. We investigated whether there is any direct route for basal ganglia output to influence cerebellar function that is independent of the cerebral cortex. We injected rabies virus (RV) into selected regions of the cerebellar cortex in cebus monkeys and used retrograde transneuronal transport of the virus to determine the origin of multisynaptic inputs to the injection sites. We found that the subthalamic nucleus of the basal ganglia has a substantial disynaptic projection to the cerebellar cortex. This pathway provides a means for both normal and abnormal signals from the basal ganglia to influence cerebellar function. We previously showed that the dentate nucleus of the cerebellum has a disynaptic projection to an input stage of basal ganglia processing, the striatum. Taken together these results provide the anatomical substrate for substantial two-way communication between the basal ganglia and cerebellum. Thus, the two subcortical structures may be linked together to form an integrated functional network. PMID:20404184

  14. Functional Neuroanatomy of the Basal Ganglia

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    Lanciego, José L.; Luquin, Natasha; Obeso, José A.

    2012-01-01

    The “basal ganglia” refers to a group of subcortical nuclei responsible primarily for motor control, as well as other roles such as motor learning, executive functions and behaviors, and emotions. Proposed more than two decades ago, the classical basal ganglia model shows how information flows through the basal ganglia back to the cortex through two pathways with opposing effects for the proper execution of movement. Although much of the model has remained, the model has been modified and amp...

  15. Meige's syndrome associated with basal ganglia and thalamic functional disorders

    International Nuclear Information System (INIS)

    Magnetic resonance imaging (MRI) or single positron emission computed tomography (SPECT) or both were performed and the responses of surface electromyography (EMG) were examined in seven cases of Meige's syndrome. MRI or SPECT or both demonstrated lesions of the basal ganglia, the thalamus, or both in five of the cases. Surface EMG revealed abnormal burst discharges in the orbicularis oculi and a failure of reciprocal muscular activity between the frontalis and orbicularis oculi in all the cases. These findings suggest that voluntary motor control and reciprocal activity in the basal ganglia-thalamocortical circuits are impaired in Meige's syndrome. In addition, good responses were seen to clonazepam, tiapride and trihexyphenidyl in these cases. Therefore, we conclude that dopaminergic, cholinergic, and γ-aminobutyric acid (GABA) ergic imbalances in the disorders of the basal ganglia and thalamus in Meige's syndrome cause control in the excitatory and inhibitory pathways to be lost, resulting in the failure of integration in reciprocal muscular activity and voluntary motor control. This failure subsequently causes the symptoms of Meige's syndrome. (author)

  16. Is Broca's area part of a basal ganglia thalamocortical circuit?

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    Ullman, Michael T

    2006-05-01

    The cortex constituting Broca's area does not exist in isolation. Rather, like other cortical regions, Broca's area is connected to other brain structures, which likely play closely related functional roles. This paper focuses on the basal ganglia, a set of subcortical structures that project through topographically organized "channels" via the thalamus to different frontal regions. It is hypothesized that the basal ganglia project to Broca's area. This circuitry is further posited to encompass at least two channels. One channel can be characterized as subserving procedural memory, while the other underlies the retrieval of knowledge from declarative memory. These hypotheses are supported by both anatomical and functional evidence. Implications and issues for further investigation are discussed. PMID:16881254

  17. Somatotopic organization of the primate basal ganglia

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    Atsushi eNambu

    2011-04-01

    Full Text Available Somatotopic organization is a fundamental and key concept to understand how the cortico-basal ganglia loop works. It is also indispensable knowledge to perform stereotaxic surgery for movement disorders. Here I would like to describe the somatotopic organization of the basal ganglia, which consist of the striatum, subthalamic nucleus, globus pallidus and substantia nigra. Projections from motor cortical regions representing different body parts terminate in different regions of these nuclei. Basal ganglia neurons respond not only to the stimulation of the corresponding regions of the motor cortices, but also to active and passive movements of the corresponding body parts. On the basis of these anatomical and physiological findings, somatotopic organization can be identified in the motor territories of these nuclei in the basal ganglia. In addition, projections from functionally interrelated cortical areas partially converge through the cortico-basal ganglia loop, but nevertheless the somatotopy is still preserved. Disorganized somatotopy may explain, at least in part, the pathophysiology of movement disorders, such as Parkinson’s disease and dystonia.

  18. The connectome of the basal ganglia.

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    Schmitt, Oliver; Eipert, Peter; Kettlitz, Richard; Leßmann, Felix; Wree, Andreas

    2016-03-01

    The basal ganglia of the laboratory rat consist of a few core regions that are specifically interconnected by efferents and afferents of the central nervous system. In nearly 800 reports of tract-tracing investigations the connectivity of the basal ganglia is documented. The readout of connectivity data and the collation of all the connections of these reports in a database allows to generate a connectome. The collation, curation and analysis of such a huge amount of connectivity data is a great challenge and has not been performed before (Bohland et al. PloS One 4:e7200, 2009) in large connectomics projects based on meta-analysis of tract-tracing studies. Here, the basal ganglia connectome of the rat has been generated and analyzed using the consistent cross-platform and generic framework neuroVIISAS. Several advances of this connectome meta-study have been made: the collation of laterality data, the network-analysis of connectivity strengths and the assignment of regions to a hierarchically organized terminology. The basal ganglia connectome offers differences in contralateral connectivity of motoric regions in contrast to other regions. A modularity analysis of the weighted and directed connectome produced a specific grouping of regions. This result indicates a correlation of structural and functional subsystems. As a new finding, significant reciprocal connections of specific network motifs in this connectome were detected. All three principal basal ganglia pathways (direct, indirect, hyperdirect) could be determined in the connectome. By identifying these pathways it was found that there exist many further equivalent pathways possessing the same length and mean connectivity weight as the principal pathways. Based on the connectome data it is unknown why an excitation pattern may prefer principal rather than other equivalent pathways. In addition to these new findings the local graph-theoretical features of regions of the connectome have been determined. By

  19. Basal ganglia orient eyes to reward.

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    Hikosaka, Okihide; Nakamura, Kae; Nakahara, Hiroyuki

    2006-02-01

    Expectation of reward motivates our behaviors and influences our decisions. Indeed, neuronal activity in many brain areas is modulated by expected reward. However, it is still unclear where and how the reward-dependent modulation of neuronal activity occurs and how the reward-modulated signal is transformed into motor outputs. Recent studies suggest an important role of the basal ganglia. Sensorimotor/cognitive activities of neurons in the basal ganglia are strongly modulated by expected reward. Through their abundant outputs to the brain stem motor areas and the thalamocortical circuits, the basal ganglia appear capable of producing body movements based on expected reward. A good behavioral measure to test this hypothesis is saccadic eye movement because its brain stem mechanism has been extensively studied. Studies from our laboratory suggest that the basal ganglia play a key role in guiding the gaze to the location where reward is available. Neurons in the caudate nucleus and the substantia nigra pars reticulata are extremely sensitive to the positional difference in expected reward, which leads to a bias in excitability between the superior colliculi such that the saccade to the to-be-rewarded position occurs more quickly. It is suggested that the reward modulation occurs in the caudate where cortical inputs carrying spatial signals and dopaminergic inputs carrying reward-related signals are integrated. These data support a specific form of reinforcement learning theories, but also suggest further refinement of the theory.

  20. Reward functions of the basal ganglia.

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    Schultz, Wolfram

    2016-07-01

    Besides their fundamental movement function evidenced by Parkinsonian deficits, the basal ganglia are involved in processing closely linked non-motor, cognitive and reward information. This review describes the reward functions of three brain structures that are major components of the basal ganglia or are closely associated with the basal ganglia, namely midbrain dopamine neurons, pedunculopontine nucleus, and striatum (caudate nucleus, putamen, nucleus accumbens). Rewards are involved in learning (positive reinforcement), approach behavior, economic choices and positive emotions. The response of dopamine neurons to rewards consists of an early detection component and a subsequent reward component that reflects a prediction error in economic utility, but is unrelated to movement. Dopamine activations to non-rewarded or aversive stimuli reflect physical impact, but not punishment. Neurons in pedunculopontine nucleus project their axons to dopamine neurons and process sensory stimuli, movements and rewards and reward-predicting stimuli without coding outright reward prediction errors. Neurons in striatum, besides their pronounced movement relationships, process rewards irrespective of sensory and motor aspects, integrate reward information into movement activity, code the reward value of individual actions, change their reward-related activity during learning, and code own reward in social situations depending on whose action produces the reward. These data demonstrate a variety of well-characterized reward processes in specific basal ganglia nuclei consistent with an important function in non-motor aspects of motivated behavior. PMID:26838982

  1. Basal ganglia lesions in children and adults.

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    Bekiesinska-Figatowska, Monika; Mierzewska, Hanna; Jurkiewicz, Elżbieta

    2013-05-01

    The term "basal ganglia" refers to caudate and lentiform nuclei, the latter composed of putamen and globus pallidus, substantia nigra and subthalamic nuclei and these deep gray matter structures belong to the extrapyramidal system. Many diseases may present as basal ganglia abnormalities. Magnetic resonance imaging (MRI) and computed tomography (CT) - to a lesser degree - allow for detection of basal ganglia injury. In many cases, MRI alone does not usually allow to establish diagnosis but together with the knowledge of age and circumstances of onset and clinical course of the disease is a powerful tool of differential diagnosis. The lesions may be unilateral: in Rassmussen encephalitis, diabetes with hemichorea/hemiballism and infarction or - more frequently - bilateral in many pathologic conditions. Restricted diffusion is attributable to infarction, acute hypoxic-ischemic injury, hypoglycemia, Leigh disease, encephalitis and CJD. Contrast enhancement may be seen in cases of infarction and encephalitis. T1-hyperintensity of the lesions is uncommon and may be observed unilaterally in case of hemichorea/hemiballism and bilaterally in acute asphyxia in term newborns, in hypoglycemia, NF1, Fahr disease and manganese intoxication. Decreased signal intensity on GRE/T2*-weighted images and/or SWI indicating iron, calcium or hemosiderin depositions is observed in panthotenate kinase-associated neurodegeneration, Parkinson variant of multiple system atrophy, Fahr disease (and other calcifications) as well as with the advancing age. There are a few papers in the literature reviewing basal ganglia lesions. The authors present a more detailed review with rich iconography from the own archive. PMID:23313708

  2. Basal ganglia lesions in children and adults

    International Nuclear Information System (INIS)

    The term “basal ganglia” refers to caudate and lentiform nuclei, the latter composed of putamen and globus pallidus, substantia nigra and subthalamic nuclei and these deep gray matter structures belong to the extrapyramidal system. Many diseases may present as basal ganglia abnormalities. Magnetic resonance imaging (MRI) and computed tomography (CT) – to a lesser degree – allow for detection of basal ganglia injury. In many cases, MRI alone does not usually allow to establish diagnosis but together with the knowledge of age and circumstances of onset and clinical course of the disease is a powerful tool of differential diagnosis. The lesions may be unilateral: in Rassmussen encephalitis, diabetes with hemichorea/hemiballism and infarction or – more frequently – bilateral in many pathologic conditions. Restricted diffusion is attributable to infarction, acute hypoxic–ischemic injury, hypoglycemia, Leigh disease, encephalitis and CJD. Contrast enhancement may be seen in cases of infarction and encephalitis. T1-hyperintensity of the lesions is uncommon and may be observed unilaterally in case of hemichorea/hemiballism and bilaterally in acute asphyxia in term newborns, in hypoglycemia, NF1, Fahr disease and manganese intoxication. Decreased signal intensity on GRE/T2*-weighted images and/or SWI indicating iron, calcium or hemosiderin depositions is observed in panthotenate kinase-associated neurodegeneration, Parkinson variant of multiple system atrophy, Fahr disease (and other calcifications) as well as with the advancing age. There are a few papers in the literature reviewing basal ganglia lesions. The authors present a more detailed review with rich iconography from the own archive

  3. Basal ganglia lesions in children and adults

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    Bekiesinska-Figatowska, Monika, E-mail: m.figatowska@mp.pl [Department of Diagnostic Imaging, Institute of Mother and Child, ul. Kasprzaka 17a, 01-211 Warsaw (Poland); Mierzewska, Hanna, E-mail: h.mierzewska@gmail.com [Department of Neurology of Children and Adolescents, Institute of Mother and Child, ul. Kasprzaka 17a, 01-211 Warsaw (Poland); Jurkiewicz, Elżbieta, E-mail: e-jurkiewicz@o2.pl [Department of Diagnostic Imaging, Children' s Memorial Health Institute, Al. Dzieci Polskich 20, 04-730 Warsaw (Poland)

    2013-05-15

    The term “basal ganglia” refers to caudate and lentiform nuclei, the latter composed of putamen and globus pallidus, substantia nigra and subthalamic nuclei and these deep gray matter structures belong to the extrapyramidal system. Many diseases may present as basal ganglia abnormalities. Magnetic resonance imaging (MRI) and computed tomography (CT) – to a lesser degree – allow for detection of basal ganglia injury. In many cases, MRI alone does not usually allow to establish diagnosis but together with the knowledge of age and circumstances of onset and clinical course of the disease is a powerful tool of differential diagnosis. The lesions may be unilateral: in Rassmussen encephalitis, diabetes with hemichorea/hemiballism and infarction or – more frequently – bilateral in many pathologic conditions. Restricted diffusion is attributable to infarction, acute hypoxic–ischemic injury, hypoglycemia, Leigh disease, encephalitis and CJD. Contrast enhancement may be seen in cases of infarction and encephalitis. T1-hyperintensity of the lesions is uncommon and may be observed unilaterally in case of hemichorea/hemiballism and bilaterally in acute asphyxia in term newborns, in hypoglycemia, NF1, Fahr disease and manganese intoxication. Decreased signal intensity on GRE/T2*-weighted images and/or SWI indicating iron, calcium or hemosiderin depositions is observed in panthotenate kinase-associated neurodegeneration, Parkinson variant of multiple system atrophy, Fahr disease (and other calcifications) as well as with the advancing age. There are a few papers in the literature reviewing basal ganglia lesions. The authors present a more detailed review with rich iconography from the own archive.

  4. Familial idiopathic basal ganglia calcification (Fahr’s disease)

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    Mufaddel, Amir A.; Al-Hassani, Ghanem A.

    2014-01-01

    Familial idiopathic basal ganglia calcification (Fahr’s disease) is a rare neurodegenerative disorder characterized by symmetrical and bilateral calcification of the basal ganglia. Calcifications may also occur in other brain regions such as dentate nucleus, thalamus, and cerebral cortex. Both familial and non-familial cases of Fahr’s disease have been reported, predominantly with autosomal-dominant fashion. The disease has a wide range of clinical presentations, predominantly with neuropsychiatric features and movement disorders. Psychiatric features reported in the literature include: cognitive impairment, depression, hallucinations, delusions, manic symptoms, anxiety, schizophrenia-like psychosis, and personality change. Other clinical features include: Parkinsonism, ataxia, headache, seizures, vertigo, stroke-like events, orthostatic hypotension, tremor, dysarthria, and paresis. Fahr’s disease should be considered in the differential diagnosis of psychiatric symptoms, particularly when associated with movement disorder. The disease should be differentiated from other conditions that can cause intracranial calcification. No specific treatment is currently available. Further research is needed to bridge the gap existing in our current knowledge of the prevalence, etiology, symptoms, and treatment of Fahr’s disease. PMID:24983277

  5. Familial idiopathic basal ganglia calcification (Fahr`s disease).

    Science.gov (United States)

    Mufaddel, Amir A; Al-Hassani, Ghanem A

    2014-07-01

    Familial idiopathic basal ganglia calcification (Fahr`s disease) is a rare neurodegenerative disorder characterized by symmetrical and bilateral calcification of the basal ganglia. Calcifications may also occur in other brain regions such as dentate nucleus, thalamus, and cerebral cortex. Both familial and non-familial cases of Fahr`s disease have been reported, predominantly with autosomal-dominant fashion. The disease has a wide range of clinical presentations, predominantly with neuropsychiatric features and movement disorders. Psychiatric features reported in the literature include: cognitive impairment, depression, hallucinations, delusions, manic symptoms, anxiety, schizophrenia-like psychosis, and personality change. Other clinical features include: Parkinsonism, ataxia, headache, seizures, vertigo, stroke-like events, orthostatic hypotension, tremor, dysarthria, and paresis. Fahr`s disease should be considered in the differential diagnosis of psychiatric symptoms, particularly when associated with movement disorder. The disease should be differentiated from other conditions that can cause intracranial calcification. No specific treatment is currently available. Further research is needed to bridge the gap existing in our current knowledge of the prevalence, etiology, symptoms, and treatment of Fahr`s disease.

  6. Mössbauer spectroscopy of Basal Ganglia

    Energy Technology Data Exchange (ETDEWEB)

    Miglierini, Marcel, E-mail: marcel.miglierini@stuba.sk [Institute of Nuclear and Physical Engineering, Faculty of Electrical Engineering and Information Technology, Slovak University of Technology, Ilkovičova 3, 812 19 Bratislava, Slovakia and Regional Centre of Advanced Technologies and Materials (Czech Republic); Lančok, Adriana [Institute of Inorganic Chemistry AS CR, v. v. i., 250 68 Husinec-Řež 1001 (Czech Republic); Kopáni, Martin [Institute of Medical Physics, Biophysics, Informatics and Telemedicine, Faculty of Medicine, Comenius University, Sasinkova 2, 811 08 Bratislava (Slovakia); Boča, Roman [Department of Chemistry, Faculty of Natural Sciences, University of SS. Cyril and Methodius, 917 01 Trnava (Slovakia)

    2014-10-27

    Chemical states, structural arrangement, and magnetic features of iron deposits in biological tissue of Basal Ganglia are characterized. The methods of SQUID magnetometry and electron microscopy are employed. {sup 57}Fe Mössbauer spectroscopy is used as a principal method of investigation. Though electron microscopy has unveiled robust crystals (1-3 μm in size) of iron oxides, they are not manifested in the corresponding {sup 57}Fe Mössbauer spectra. The latter were acquired at 300 K and 4.2 K and resemble ferritin-like behavior.

  7. Sequence learning in a model of the basal ganglia

    OpenAIRE

    Søiland, Stian

    2006-01-01

    This thesis presents a computational model of the basal ganglia that is able to learn sequences and perform action selection. The basal ganglia is a set of structures in the human brain involved in everything from action selection to reinforcement learning, inspiring research in psychology, neuroscience and computer science. Two temporal difference models of the basal ganglia based on previous work have been reimplemented. Several experiments and analyses help understand and describe the or...

  8. Covert skill learning in a cortical-basal ganglia circuit

    OpenAIRE

    Charlesworth, JD; Warren, TL; Brainard, MS

    2012-01-01

    We learn complex skills such as speech and dance through a gradual process of trial and error. Cortical-basal ganglia circuits have an important yet unresolved function in this trial-and-error skill learning; influential ' actor-models propose that basal ganglia circuits generate a variety of behaviours during training and learn to implement the successful behaviours in their repertoire. Here we show that the anterior forebrain pathway (AFP), a cortical-basal ganglia circuit, contributes to s...

  9. Hypofractionated Stereotactic Radiosurgery in a Large Bilateral Thalamic and Basal Ganglia Arteriovenous Malformation

    Directory of Open Access Journals (Sweden)

    Janet Lee

    2013-01-01

    Full Text Available Purpose. Arteriovenous malformations (AVMs in the basal ganglia and thalamus have a more aggressive natural history with a higher morbidity and mortality than AVMs in other locations. Optimal treatment—complete obliteration without new neurological deficits—is often challenging. We present a patient with a large bilateral basal ganglia and thalamic AVM successfully treated with hypofractionated stereotactic radiosurgery (HFSRS with intensity modulated radiotherapy (IMRT. Methods. The patient was treated with hypofractionated stereotactic radiosurgery to 30 Gy at margin in 5 fractions of 9 static fields with a minimultileaf collimator and intensity modulated radiotherapy. Results. At 10 months following treatment, digital subtraction angiography showed complete obliteration of the AVM. Conclusions. Large bilateral thalamic and basal ganglia AVMs can be successfully treated with complete obliteration by HFSRS with IMRT with relatively limited toxicity. Appropriate caution is recommended.

  10. Mineralizing angiopathy with basal ganglia stroke in an infant

    Directory of Open Access Journals (Sweden)

    Puneet Jain

    2015-01-01

    Full Text Available Basal ganglia stroke is known following trivial head trauma. Recently a distinct clinic-radiological entity termed ′mineralizing angiopathy′ was described. We report an infant who developed basal ganglia stroke following trivial fall. His clinic-radiological features are described.

  11. Cardiorespiratory fitness and its association with thalamic, hippocampal, and basal ganglia volumes in multiple sclerosis

    OpenAIRE

    Motl, Robert W.; Pilutti, Lara A.; Hubbard, Elizabeth A.; Wetter, Nathan C.; Sosnoff, Jacob J.; Sutton, Bradley P.

    2015-01-01

    Background: There is little known about cardiorespiratory fitness and its association with volumes of the thalamus, hippocampus, and basal ganglia in multiple sclerosis (MS). Such inquiry is important for identifying a possible behavioral approach (e.g., aerobic exercise training) that might change volumes of deep gray matter (DGM) structures associated with cognitive and motor functions in MS. Purpose: This study examined the association between cardiorespiratory fitness and volumes of th...

  12. Cortico-Basal Ganglia Circuit Function in Psychiatric Disease.

    Science.gov (United States)

    Gunaydin, Lisa A; Kreitzer, Anatol C

    2016-01-01

    Circuit dysfunction models of psychiatric disease posit that pathological behavior results from abnormal patterns of electrical activity in specific cells and circuits in the brain. Many psychiatric disorders are associated with abnormal activity in the prefrontal cortex and in the basal ganglia, a set of subcortical nuclei implicated in cognitive and motor control. Here we discuss the role of the basal ganglia and connected prefrontal regions in the etiology and treatment of obsessive-compulsive disorder, anxiety, and depression, emphasizing mechanistic work in rodent behavioral models to dissect causal cortico-basal ganglia circuits underlying discrete behavioral symptom domains relevant to these complex disorders. PMID:26667072

  13. Cardiorespiratory fitness and its association with thalamic, hippocampal, and basal ganglia volumes in multiple sclerosis

    Science.gov (United States)

    Motl, Robert W.; Pilutti, Lara A.; Hubbard, Elizabeth A.; Wetter, Nathan C.; Sosnoff, Jacob J.; Sutton, Bradley P.

    2015-01-01

    Background There is little known about cardiorespiratory fitness and its association with volumes of the thalamus, hippocampus, and basal ganglia in multiple sclerosis (MS). Such inquiry is important for identifying a possible behavioral approach (e.g., aerobic exercise training) that might change volumes of deep gray matter (DGM) structures associated with cognitive and motor functions in MS. Purpose This study examined the association between cardiorespiratory fitness and volumes of the thalamus, hippocampus, and basal ganglia in MS. Method We enrolled 35 persons with MS who underwent a maximal exercise test for measuring cardiorespiratory fitness as peak oxygen consumption (VO2peak) and brain MRI. Volumes of the thalamus, hippocampus, caudate, putamen, and pallidum were calculated from 3D T1-weighted structural brain images. We examined associations using partial (pr) correlations controlling for demographic and clinical variables. Results VO2peak was significantly associated with composite scaled volumes of the caudate(pr = .47, p < .01), putamen (pr = .44, p < .05), pallidum (pr = .40, p < .05), and hippocampus (pr = .42, p < .05), but not thalamus (pr = .31, p = .09), when controlling for sex, age, disability, and duration of MS. Conclusion Our results provide novel evidence that cardiorespiratory fitness is associated with volumes of DGM structures that are involved in motor and cognitive functions in MS. PMID:25844320

  14. Basal ganglia calcification on computed tomography in systemic lupus erythematosus

    International Nuclear Information System (INIS)

    The development of basal ganglia calcification was studied in 85 patients with systemic lupus erythematosus (SLE) by computed tomography (CT). Bilateral calcification of the basal ganglia was found to occur in 5 patients (5.9 %) with SLE, but was not seen in patients with rheumatoid arthritis and progressive systemic sclerosis. All were female with a mean age of 42 years (range 29 - 49). The patients with calcification of the basal ganglia had neurological symptoms, such as psychiatric problems (3 cases), grand mal seizures (1 case), CSF abnormalities (2 cases), and EEG changes (4 cases). There were significantly higher incidences of alopecia, cutaneous vasculitis, leukopenia, and thrombocytopenia in the group with calcifications than those in the group with normal CT findings. Circulating immune complexes were detected and LE tests were positive in 2 patients. Endocrinological examination showed no abnormality in any. We suggest that basal ganglia calcification in SLE might be related to cerebral vasculitis. (author)

  15. Basal ganglia calcification on computed tomography in systemic lupus erythematosus

    Energy Technology Data Exchange (ETDEWEB)

    Nagaoka, Shohei; Tani, Kenji; Ishigatsubo, Yoshiaki and others

    1988-09-01

    The development of basal ganglia calcification was studied in 85 patients with systemic lupus erythematosus (SLE) by computed tomography (CT). Bilateral calcification of the basal ganglia was found to occur in 5 patients (5.9 %) with SLE, but was not seen in patients with rheumatoid arthritis and progressive systemic sclerosis. All were female with a mean age of 42 years (range 29 - 49). The patients with calcification of the basal ganglia had neurological symptoms, such as psychiatric problems (3 cases), grand mal seizures (1 case), CSF abnormalities (2 cases), and EEG changes (4 cases). There were significantly higher incidences of alopecia, cutaneous vasculitis, leukopenia, and thrombocytopenia in the group with calcifications than those in the group with normal CT findings. Circulating immune complexes were detected and LE tests were positive in 2 patients. Endocrinological examination showed no abnormality in any. We suggest that basal ganglia calcification in SLE might be related to cerebral vasculitis.

  16. Short latency cerebellar modulation of the basal ganglia.

    Science.gov (United States)

    Chen, Christopher H; Fremont, Rachel; Arteaga-Bracho, Eduardo E; Khodakhah, Kamran

    2014-12-01

    The graceful, purposeful motion of our body is an engineering feat that remains unparalleled in robotic devices using advanced artificial intelligence. Much of the information required for complex movements is generated by the cerebellum and the basal ganglia in conjunction with the cortex. Cerebellum and basal ganglia have been thought to communicate with each other only through slow, multi-synaptic cortical loops, begging the question as to how they coordinate their outputs in real time. We found that the cerebellum rapidly modulates the activity of the striatum via a disynaptic pathway in mice. Under physiological conditions, this short latency pathway was capable of facilitating optimal motor control by allowing the basal ganglia to incorporate time-sensitive cerebellar information and by guiding the sign of cortico-striatal plasticity. Conversely, under pathological condition, this pathway relayed aberrant cerebellar activity to the basal ganglia to cause dystonia. PMID:25402853

  17. Meige`s syndrome associated with basal ganglia and thalamic functional disorders

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Tsutomu; Shikishima, Keigo; Kawai, Kazushige; Kitahara, Kenji [Jikei Univ., Tokyo (Japan). School of Medicine

    1998-11-01

    Magnetic resonance imaging (MRI) or single positron emission computed tomography (SPECT) or both were performed and the responses of surface electromyography (EMG) were examined in seven cases of Meige`s syndrome. MRI or SPECT or both demonstrated lesions of the basal ganglia, the thalamus, or both in five of the cases. Surface EMG revealed abnormal burst discharges in the orbicularis oculi and a failure of reciprocal muscular activity between the frontalis and orbicularis oculi in all the cases. These findings suggest that voluntary motor control and reciprocal activity in the basal ganglia-thalamocortical circuits are impaired in Meige`s syndrome. In addition, good responses were seen to clonazepam, tiapride and trihexyphenidyl in these cases. Therefore, we conclude that dopaminergic, cholinergic, and {gamma}-aminobutyric acid (GABA) ergic imbalances in the disorders of the basal ganglia and thalamus in Meige`s syndrome cause control in the excitatory and inhibitory pathways to be lost, resulting in the failure of integration in reciprocal muscular activity and voluntary motor control. This failure subsequently causes the symptoms of Meige`s syndrome. (author)

  18. [Cortico-basal ganglia circuits--parallel closed loops and convergent/divergent connections].

    Science.gov (United States)

    Miyachi, Shigehiro

    2009-04-01

    The basal ganglia play important roles not only in motor control but also in higher cognitive functions such as reinforcement learning and procedural memory. Anatomical studies on the neuronal connections between the basal ganglia, cerebral cortex, and thalamus have demonstrated that these nuclei and cortical areas are interconnected via independent parallel loop circuits. The association, motor, and limbic cortices project to specific domains in the striatum, which, in turn, project back to the corresponding cortical areas via the substantia nigra/globus pallidus and the thalamus. Likewise, subregions in the motor cortex representing different body parts project to specific regions in the putamen, which project back to the original motor cortical regions. These parallel loops have been thought to be the basic anatomical structures involved in the basal ganglia functions. Furthermore, neuronal projections communicating between different loops (or functional domains) have also been discovered. A considerable number of corticostriatal projections from functionally interrelated cortical areas (e. g., hand representations of the motor cortex and somatosensory cortex) converge at the striatum. It has also been suggested that the location of the substantia nigra is in such that it can transmit information from the 'limbic loop' to the 'association loop', and from the 'association loop' to the 'motor loop'. Furthermore, a recent transsynaptic neuronal tracing study conducted at our laboratory demonstrated that the ventral (limbic) striatum sends divergent outputs to multiple regions in the frontal cortex. These 'inter-loop' connections would be important for the integration of information to achieve goal-directed behaviors. PMID:19378804

  19. Opponent and bidirectional control of movement velocity in the basal ganglia.

    Science.gov (United States)

    Yttri, Eric A; Dudman, Joshua T

    2016-05-19

    For goal-directed behaviour it is critical that we can both select the appropriate action and learn to modify the underlying movements (for example, the pitch of a note or velocity of a reach) to improve outcomes. The basal ganglia are a critical nexus where circuits necessary for the production of behaviour, such as the neocortex and thalamus, are integrated with reward signalling to reinforce successful, purposive actions. The dorsal striatum, a major input structure of basal ganglia, is composed of two opponent pathways, direct and indirect, thought to select actions that elicit positive outcomes and suppress actions that do not, respectively. Activity-dependent plasticity modulated by reward is thought to be sufficient for selecting actions in the striatum. Although perturbations of basal ganglia function produce profound changes in movement, it remains unknown whether activity-dependent plasticity is sufficient to produce learned changes in movement kinematics, such as velocity. Here we use cell-type-specific stimulation in mice delivered in closed loop during movement to demonstrate that activity in either the direct or indirect pathway is sufficient to produce specific and sustained increases or decreases in velocity, without affecting action selection or motivation. These behavioural changes were a form of learning that accumulated over trials, persisted after the cessation of stimulation, and were abolished in the presence of dopamine antagonists. Our results reveal that the direct and indirect pathways can each bidirectionally control movement velocity, demonstrating unprecedented specificity and flexibility in the control of volition by the basal ganglia.

  20. Alterations in Neuronal Activity in Basal Ganglia-Thalamocortical Circuits in the Parkinsonian State

    Directory of Open Access Journals (Sweden)

    Adriana eGalvan

    2015-02-01

    Full Text Available In patients with Parkinson’s disease and in animal models of this disorder, neurons in the basal ganglia and related regions in thalamus and cortex show changes that can be recorded by using electrophysiologic single-cell recording techniques, including altered firing rates and patterns, pathologic oscillatory activity and increased inter-neuronal synchronization. In addition, changes in synaptic potentials or in the joint spiking activities of populations of neurons can be monitored as alterations in local field potentials, electroencephalograms or electrocorticograms. Most of the mentioned electrophysiologic changes are probably related to the degeneration of diencephalic dopaminergic neurons, leading to dopamine loss in the striatum and other basal ganglia nuclei, although degeneration of non-dopaminergic cell groups may also have a role. The altered electrical activity of the basal ganglia and associated nuclei may contribute to some of the motor signs of the disease. We here review the current knowledge of the electrophysiologic changes at the single cell level, the level of local populations of neural elements, and the level of the entire basal ganglia-thalamocortical network in parkinsonism, and discuss the possible use of this information to optimize treatment approaches to Parkinson’s disease, such as deep brain stimulation therapy.

  1. Opponent and bidirectional control of movement velocity in the basal ganglia.

    Science.gov (United States)

    Yttri, Eric A; Dudman, Joshua T

    2016-05-02

    For goal-directed behaviour it is critical that we can both select the appropriate action and learn to modify the underlying movements (for example, the pitch of a note or velocity of a reach) to improve outcomes. The basal ganglia are a critical nexus where circuits necessary for the production of behaviour, such as the neocortex and thalamus, are integrated with reward signalling to reinforce successful, purposive actions. The dorsal striatum, a major input structure of basal ganglia, is composed of two opponent pathways, direct and indirect, thought to select actions that elicit positive outcomes and suppress actions that do not, respectively. Activity-dependent plasticity modulated by reward is thought to be sufficient for selecting actions in the striatum. Although perturbations of basal ganglia function produce profound changes in movement, it remains unknown whether activity-dependent plasticity is sufficient to produce learned changes in movement kinematics, such as velocity. Here we use cell-type-specific stimulation in mice delivered in closed loop during movement to demonstrate that activity in either the direct or indirect pathway is sufficient to produce specific and sustained increases or decreases in velocity, without affecting action selection or motivation. These behavioural changes were a form of learning that accumulated over trials, persisted after the cessation of stimulation, and were abolished in the presence of dopamine antagonists. Our results reveal that the direct and indirect pathways can each bidirectionally control movement velocity, demonstrating unprecedented specificity and flexibility in the control of volition by the basal ganglia.

  2. Genetics Home Reference: familial idiopathic basal ganglia calcification

    Science.gov (United States)

    ... Wang QK, Liu JY. Identification of a novel genetic locus on chromosome 8p21.1-q11.23 for idiopathic ... DH. Analysis of candidate genes at the IBGC1 locus associated with idiopathic basal ... DH. Genetic heterogeneity in familial idiopathic basal ganglia calcification (Fahr ...

  3. Crossed cerebellar and uncrossed basal ganglia and thalamic diaschisis in Alzheimer's disease

    International Nuclear Information System (INIS)

    We detected crossed cerebellar as well as uncrossed basal ganglia and thalamic diaschisis in Alzheimer's disease by positron emission tomography (PET) using 18F-fluorodeoxyglucose. We studied a series of 26 consecutive, clinically diagnosed Alzheimer cases, including 6 proven by later autopsy, and compared them with 9 age-matched controls. We calculated asymmetry indices (AIs) of cerebral metabolic rate for matched left-right regions of interest (ROIs) and determined the extent of diaschisis by correlative analyses. For the Alzheimer group, we found cerebellar AIs correlated negatively, and thalamic AIs positively, with those of the cerebral hemisphere and frontal, temporal, parietal, and angular cortices, while basal ganglia AIs correlated positively with frontal cortical AIs. The only significant correlation of AIs for normal subjects was between the thalamus and cerebral hemisphere. These data indicate that PET is a sensitive technique for detecting diaschisis

  4. Dopamine-glutamate interactions in the basal ganglia.

    Science.gov (United States)

    Schmidt, W J

    1998-01-01

    In an attempt to formulate a working hypothesis of basal-ganglia functions, arguments are considered suggesting that the basal ganglia are involved in a process of response selection i.e. in the facilitation of "wanted" and in the suppression of "unwanted" behaviour. The meso-accumbal dopamine-system is considered to mediate natural and drug-induced reward and sensitization. The meso-striatal dopamine-system seems to fulfill similar functions: It may mediate reinforcement which strengthens a given behaviour when elicited subsequently, but which is not experienced as reward or hedonia. Glutamate as the transmitter of the corticofugal projections to the basal ganglia nuclei and of the subthalamic neurons is critically involved in basal ganglia functions and dysfunctions; for example Parkinson's disease can be considered to be a secondary hyperglutamatergic disease. Additionally, glutamate is an essential factor in the plasticity response of the basal-ganglia. However, opposite to previous suggestions, the NMDA-receptor blocker MK-801 does not prevent psychostimulant- nor morphine-induced day to day increase (sensitization) of locomotion. Also the day to day increase of haloperidol-induced catalepsy was not prevented by MK-801. PMID:9871434

  5. Singing-related neural activity distinguishes two putative pallidal cell types in the songbird basal ganglia: comparison to the primate internal and external pallidal segments

    OpenAIRE

    Goldberg, Jesse H.; Adler, Avital; Bergman, Hagai; Fee, Michale S

    2010-01-01

    The songbird area X is a basal ganglia homologue that contains two pallidal cell types—local neurons that project within the basal ganglia and output neurons that project to the thalamus. Based on these projections, it has been proposed that these classes are structurally homologous to the primate external (GPe) and internal (GPi) pallidal segments. To test the hypothesis that the two area X pallidal types are functionally homologous to GPe and GPi neurons, we recorded from neurons in area X ...

  6. Loss of function of Slc20a2 associated with familial idiopathic basal ganglia calcification in humans causes brain calcifications in mice

    DEFF Research Database (Denmark)

    Jensen, Nina; Daa Schrøder, Henrik; Kildall Hejbøl, Eva;

    2013-01-01

    Familial idiopathic basal ganglia calcification (FIBGC) is a neurodegenerative disorder with neuropsychiatric and motor symptoms. Deleterious mutations in SLC20A2, encoding the type III sodium-dependent phosphate transporter 2 (PiT2), were recently linked to FIBGC in almost 50 % of the families...... reported worldwide. Here, we show that knockout of Slc20a2 in mice causes calcifications in the thalamus, basal ganglia, and cortex, demonstrating that reduced PiT2 expression alone can cause brain calcifications....

  7. Synchronizing activity of basal ganglia and pathophysiology of Parkinson's disease.

    Science.gov (United States)

    Heimer, G; Rivlin, M; Israel, Z; Bergman, H

    2006-01-01

    Early physiological studies emphasized changes in the discharge rate of basal ganglia in the pathophysiology of Parkinson's disease (PD), whereas recent studies stressed the role of the abnormal oscillatory activity and neuronal synchronization of pallidal cells. However, human observations cast doubt on the synchronization hypothesis since increased synchronization may be an epi-phenomenon of the tremor or of independent oscillators with similar frequency. Here, we show that modern actor/ critic models of the basal ganglia predict the emergence of synchronized activity in PD and that significant non-oscillatory and oscillatory correlations are found in MPTP primates. We conclude that the normal fluctuation of basal ganglia dopamine levels combined with local cortico-striatal learning rules lead to noncorrelated activity in the pallidum. Dopamine depletion, as in PD, results in correlated pallidal activity, and reduced information capacity. We therefore suggest that future deep brain stimulation (DBS) algorithms may be improved by desynchronizing pallidal activity. PMID:17017503

  8. Covert skill learning in a cortical-basal ganglia circuit.

    Science.gov (United States)

    Charlesworth, Jonathan D; Warren, Timothy L; Brainard, Michael S

    2012-06-14

    We learn complex skills such as speech and dance through a gradual process of trial and error. Cortical-basal ganglia circuits have an important yet unresolved function in this trial-and-error skill learning; influential 'actor-critic' models propose that basal ganglia circuits generate a variety of behaviours during training and learn to implement the successful behaviours in their repertoire. Here we show that the anterior forebrain pathway (AFP), a cortical-basal ganglia circuit, contributes to skill learning even when it does not contribute to such 'exploratory' variation in behavioural performance during training. Blocking the output of the AFP while training Bengalese finches to modify their songs prevented the gradual improvement that normally occurs in this complex skill during training. However, unblocking the output of the AFP after training caused an immediate transition from naive performance to excellent performance, indicating that the AFP covertly gained the ability to implement learned skill performance without contributing to skill practice. In contrast, inactivating the output nucleus of the AFP during training completely prevented learning, indicating that learning requires activity within the AFP during training. Our results suggest a revised model of skill learning: basal ganglia circuits can monitor the consequences of behavioural variation produced by other brain regions and then direct those brain regions to implement more successful behaviours. The ability of the AFP to identify successful performances generated by other brain regions indicates that basal ganglia circuits receive a detailed efference copy of premotor activity in those regions. The capacity of the AFP to implement successful performances that were initially produced by other brain regions indicates precise functional connections between basal ganglia circuits and the motor regions that directly control performance. PMID:22699618

  9. A resting state network in the motor control circuit of the basal ganglia

    Directory of Open Access Journals (Sweden)

    Bruzzone Lorenzo

    2009-11-01

    Full Text Available Abstract Background In the absence of overt stimuli, the brain shows correlated fluctuations in functionally related brain regions. Approximately ten largely independent resting state networks (RSNs showing this behaviour have been documented to date. Recent studies have reported the existence of an RSN in the basal ganglia - albeit inconsistently and without the means to interpret its function. Using two large study groups with different resting state conditions and MR protocols, the reproducibility of the network across subjects, behavioural conditions and acquisition parameters is assessed. Independent Component Analysis (ICA, combined with novel analyses of temporal features, is applied to establish the basis of signal fluctuations in the network and its relation to other RSNs. Reference to prior probabilistic diffusion tractography work is used to identify the basal ganglia circuit to which these fluctuations correspond. Results An RSN is identified in the basal ganglia and thalamus, comprising the pallidum, putamen, subthalamic nucleus and substantia nigra, with a projection also to the supplementary motor area. Participating nuclei and thalamo-cortical connection probabilities allow this network to be identified as the motor control circuit of the basal ganglia. The network was reproducibly identified across subjects, behavioural conditions (fixation, eyes closed, field strength and echo-planar imaging parameters. It shows a frequency peak at 0.025 ± 0.007 Hz and is most similar in spectral composition to the Default Mode (DM, a network of regions that is more active at rest than during task processing. Frequency features allow the network to be classified as an RSN rather than a physiological artefact. Fluctuations in this RSN are correlated with those in the task-positive fronto-parietal network and anticorrelated with those in the DM, whose hemodynamic response it anticipates. Conclusion Although the basal ganglia RSN has not been

  10. Mephedrone alters basal ganglia and limbic neurotensin systems.

    Science.gov (United States)

    German, Christopher L; Hoonakker, Amanda H; Fleckenstein, Annette E; Hanson, Glen R

    2014-08-01

    Mephedrone (4-methylmethcathinone) is a synthetic cathinone designer drug that alters pre-synaptic dopamine (DA) activity like many psychostimulants. However, little is known about the post-synaptic dopaminergic impacts of mephedrone. The neuropeptide neurotensin (NT) provides inhibitory feedback for basal ganglia and limbic DA pathways, and post-synaptic D1 -like and D2 -like receptor activity affects NT tissue levels. This study evaluated how mephedrone alters basal ganglia and limbic system NT content and the role of NT receptor activation in drug consumption behavior. Four 25 mg/kg injections of mephedrone increased NT content in basal ganglia (striatum, substantia nigra and globus pallidus) and the limbic regions (nucleus accumbens core), while a lower dosage (5 mg/kg/injection) only increased striatal NT content. Mephedrone-induced increases in basal ganglia NT levels were mediated by D1 -like receptors in the striatum and the substantia nigra by both D1 -like and D2 -like receptors in the globus pallidus. Mephedrone increased substance P content, another neuropeptide, in the globus pallidus, but not in the dorsal striatum or substantia nigra. Finally, the NT receptor agonist PD149163 blocked mephedrone self-administration, suggesting reduced NT release, as indicated by increased tissue levels, likely contributing to patterns of mephedrone consumption.

  11. MRI pattern of infarcts in basal ganglia region in patients with tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Nair, P.P.; Kalita, J.; Misra, U.K. [Sanjay Gandhi Postgraduate Institute of Medical Sciences, Department of Neurology, Lucknow (India); Kumar, S. [Sanjay Gandhi Postgraduate Institute of Medical sciences, Department of Radiology, Lucknow (India)

    2009-04-15

    This study aimed to evaluate the pattern of infarct in basal ganglia region in tuberculous meningitis (TBM) and ischemic strokes and its sensitivity and specificity in the diagnosis of these disorders. Patients with TBM and ischemic strokes in basal ganglia region were retrospectively evaluated from our tuberculous meningitis and ischemic stroke registry. Magnetic resonance imaging findings were grouped into anterior (caudate, genu, anterior limb of internal capsule, anteromedial thalamus) and posterior (lentiform nuclei, posterior limb of internal capsule, posterolateral thalamus). The sensitivity and specificity of these patterns in diagnosing TBM and ischemic stroke were evaluated. There were 24 patients in each group. Infarct in TBM was purely anterior in eight patients and in ischemic stroke purely posterior in 18 patients. The frequency of caudate infarct was significantly higher in TBM compared to ischemic stroke (37.5% vs 8.3%). In TBM patients, purely posterior infarcts were present in seven patients; three had associated risk factors of ischemic stroke. The sensitivity of pure anterior infarct in the diagnosis of TBM was 33%, specificity 91.66%. For ischemic stroke, the sensitivity of posterior infarct was 75% and specificity 70.83%. TBM patients having infarcts in posterior region should be looked for associated risk factors of ischemic stroke. (orig.)

  12. Basal ganglia modulation of thalamocortical relay in Parkinson’s disease and dystonia

    Directory of Open Access Journals (Sweden)

    Yixin eGuo

    2013-09-01

    Full Text Available Basal ganglia dysfunction has being implied in both Parkinson's disease and dystonia. While these disorders probably involve different cellular and circuit pathologies within and beyond basal ganglia, there may be some shared neurophysiological pathways. For example, pallidotomy and pallidal Deep Brain Stimulation (DBS are used in symptomatic treatment of both disorders. Both conditions are marked by alterations of rhythmicity of neural activity throughout basal ganglia-thalamocortical circuits. Increased synchronized oscillatory activity in beta band is characteristic of Parkinson’s disease, while different frequency bands, theta and alpha, are involved in dystonia. We compare the effect of the activity of GPi, the output nuclei of the basal ganglia, on the information processing in the downstream neural circuits of thalamus in Parkinson’s disease and dystonia. We use a data-driven computational approach, a computational model of the thalamocortical (TC cell modulated by experimentally recorded data, to study the differences and similarities of thalamic dynamics in dystonia and Parkinson's disease. Our analysis shows no substantial differences in TC relay between the two conditions. Our results suggest that, similar to Parkinson’s disease, a disruption of thalamic processing could also be involved in dystonia. Moreover, the degree to which TC relay fidelity is impaired is approximately the same in both conditions. While Parkinson’s disease and dystonia may have different pathologies and differ in the oscillatory content of neural discharge, our results suggest that the effect of patterning of pallidal discharge is similar in both conditions. Furthermore, these results suggest that the mechanisms of GPi DBS in dystonia maybe involve improvement of TC relay fidelity.

  13. Basal ganglia modulation of thalamocortical relay in Parkinson's disease and dystonia.

    Science.gov (United States)

    Guo, Yixin; Park, Choongseok; Worth, Robert M; Rubchinsky, Leonid L

    2013-01-01

    Basal ganglia dysfunction has being implied in both Parkinson's disease and dystonia. While these disorders probably involve different cellular and circuit pathologies within and beyond basal ganglia, there may be some shared neurophysiological pathways. For example, pallidotomy and pallidal Deep Brain Stimulation (DBS) are used in symptomatic treatment of both disorders. Both conditions are marked by alterations of rhythmicity of neural activity throughout basal ganglia-thalamocortical circuits. Increased synchronized oscillatory activity in beta band is characteristic of Parkinson's disease, while different frequency bands, theta and alpha, are involved in dystonia. We compare the effect of the activity of GPi, the output nuclei of the basal ganglia, on information processing in the downstream neural circuits of thalamus in Parkinson's disease and dystonia. We use a data-driven computational approach, a computational model of the thalamocortical (TC) cell modulated by experimentally recorded data, to study the differences and similarities of thalamic dynamics in dystonia and Parkinson's disease. Our analysis shows no substantial differences in TC relay between the two conditions. Our results suggest that, similar to Parkinson's disease, a disruption of thalamic processing could also be involved in dystonia. Moreover, the degree to which TC relay fidelity is impaired is approximately the same in both conditions. While Parkinson's disease and dystonia may have different pathologies and differ in the oscillatory content of neural discharge, our results suggest that the effect of patterning of pallidal discharge is similar in both conditions. Furthermore, these results suggest that the mechanisms of GPi DBS in dystonia may involve improvement of TC relay fidelity.

  14. Mean-field modeling of the basal ganglia-thalamocortical system. II Dynamics of parkinsonian oscillations.

    Science.gov (United States)

    van Albada, S J; Gray, R T; Drysdale, P M; Robinson, P A

    2009-04-21

    Neuronal correlates of Parkinson's disease (PD) include a shift to lower frequencies in the electroencephalogram (EEG) and enhanced synchronized oscillations at 3-7 and 7-30 Hz in the basal ganglia, thalamus, and cortex. This study describes the dynamics of a recent physiologically based mean-field model of the basal ganglia-thalamocortical system, and shows how it accounts for many key electrophysiological correlates of PD. Its detailed functional connectivity comprises partially segregated direct and indirect pathways through two populations of striatal neurons, a hyperdirect pathway involving a corticosubthalamic projection, thalamostriatal feedback, and local inhibition in striatum and external pallidum (GPe). In a companion paper, realistic steady-state firing rates were obtained for the healthy state, and after dopamine loss modeled by weaker direct and stronger indirect pathways, reduced intrapallidal inhibition, lower firing thresholds of the GPe and subthalamic nucleus (STN), a stronger projection from striatum to GPe, and weaker cortical interactions. Here it is shown that oscillations around 5 and 20 Hz can arise with a strong indirect pathway, which also causes increased synchronization throughout the basal ganglia. Furthermore, increased theta power with progressive nigrostriatal degeneration is correlated with reduced alpha power and peak frequency, in agreement with empirical results. Unlike the hyperdirect pathway, the indirect pathway sustains oscillations with phase relationships that coincide with those found experimentally. Alterations in the responses of basal ganglia to transient stimuli accord with experimental observations. Reduced cortical gains due to both nigrostriatal and mesocortical dopamine loss lead to slower changes in cortical activity and may be related to bradykinesia. Finally, increased EEG power found in some studies may be partly explained by a lower effective GPe firing threshold, reduced GPe-GPe inhibition, and/or weaker

  15. Functional Neuroanatomy and Behavioural Correlates of the Basal Ganglia: Evidence from Lesion Studies

    Directory of Open Access Journals (Sweden)

    Peter Ward

    2013-01-01

    Full Text Available Introduction: The basal ganglia are interconnected with cortical areas involved in behavioural, cognitive and emotional processes, in addition to movement regulation. Little is known about which of these functions are associated with individual basal ganglia substructures.

  16. Morphological elucidation of basal ganglia circuits contributing reward prediction.

    Science.gov (United States)

    Fujiyama, Fumino; Takahashi, Susumu; Karube, Fuyuki

    2015-01-01

    Electrophysiological studies in monkeys have shown that dopaminergic neurons respond to the reward prediction error. In addition, striatal neurons alter their responsiveness to cortical or thalamic inputs in response to the dopamine signal, via the mechanism of dopamine-regulated synaptic plasticity. These findings have led to the hypothesis that the striatum exhibits synaptic plasticity under the influence of the reward prediction error and conduct reinforcement learning throughout the basal ganglia circuits. The reinforcement learning model is useful; however, the mechanism by which such a process emerges in the basal ganglia needs to be anatomically explained. The actor-critic model has been previously proposed and extended by the existence of role sharing within the striatum, focusing on the striosome/matrix compartments. However, this hypothesis has been difficult to confirm morphologically, partly because of the complex structure of the striosome/matrix compartments. Here, we review recent morphological studies that elucidate the input/output organization of the striatal compartments. PMID:25698913

  17. [Morphological Re-evaluation of the Basal Ganglia Network].

    Science.gov (United States)

    Fujiyama, Fumino

    2016-07-01

    Electrophysiological studies in monkeys have shown that dopaminergic neurons respond to the reward prediction error. In addition, striatal neurons alter their responsiveness to cortical or thalamic inputs in response to dopamine signals, via dopamine-regulated synaptic plasticity. These findings have led to the hypothesis that the striatum exhibits synaptic plasticity under the influence of reward prediction error and conducts reinforcement learning throughout the basal ganglia circuits. The reinforcement learning model is useful; however, the mechanism by which such a process emerges in the basal ganglia needs to be anatomically explained. The actor-critic model has been previously proposed and extended by the existence of role sharing within the striatum, with particular focus on the striosome and matrix compartments. However, this hypothesis has been difficult to confirm morphologically, partly because of the complex structure of the striosome and matrix compartments. Here, we review recent morphological studies that elucidate the input/output organization of the striatal compartments. PMID:27395470

  18. Cerebellar networks with the cerebral cortex and basal ganglia.

    Science.gov (United States)

    Bostan, Andreea C; Dum, Richard P; Strick, Peter L

    2013-05-01

    The dominant view of cerebellar function has been that it is exclusively concerned with motor control and coordination. Recent findings from neuroanatomical, behavioral, and imaging studies have profoundly changed this view. Neuroanatomical studies using virus transneuronal tracers have demonstrated that cerebellar output reaches vast areas of the neocortex, including regions of prefrontal and posterior parietal cortex. Furthermore, it has recently become clear that the cerebellum is reciprocally connected with the basal ganglia, which suggests that the two subcortical structures are part of a densely interconnected network. Taken together, these findings elucidate the neuroanatomical substrate for cerebellar involvement in non-motor functions mediated by the prefrontal and posterior parietal cortex, as well as in processes traditionally associated with the basal ganglia. PMID:23579055

  19. Subsystems of the basal ganglia and motor infrastructure

    OpenAIRE

    Kamali Sarvestani, Iman

    2013-01-01

    The motor nervous system is one of the main systems of the body and is our principle means ofbehavior. Some of the most debilitating and wide spread disorders are motor systempathologies. In particular the basal ganglia are complex networks of the brain that control someaspects of movement in all vertebrates. Although these networks have been extensively studied,lack of proper methods to study them on a system level has hindered the process ofunderstanding what they do and how they do it. In ...

  20. Youth hypertension cerebral hemorrhage in basal ganglia surgery operation analysis

    Institute of Scientific and Technical Information of China (English)

    Qi-Hua Wang; Da-Shuang Lu; Jie Cui; Bo-Lin Qiao; Jing-Chun Wang

    2016-01-01

    Objective:Discuss surgical treatment of youth hypertension cerebral hemorrhage in basal ganglia.Methods:Retrospective analysis from January 2012 to April 2015 were adopted to bone flap craniotomy decompression for removal of hematoma and drainage drilling two kinds of surgical treatment of 46 cases of young patients with hypertension cerebral hemorrhage in basal ganglia.Results:Surgical operation, 28 patients postoperative review head CT, no further hemorrhage cases, residual hematoma volume 2-6 mL. Drilling drainage in the treatment of 18 patients, 1 case was bleeding again given surgical operation to remove the hematoma and the rest of the 17 cases without bleeding again, after 3 d, 17 cases of patients of postoperative hematoma drainage thoroughly. After 6 months, 46 cases of patients with postoperative review, GOS score light disability 9 cases, moderate disability 33 cases, 4 cases were severely disabled, curative effect is satisfied.Conclusions:Two kinds of operative methods each have advantages and disadvantages, young patients with hypertension cerebral hemorrhage in basal ganglia should according to patients' disease progression after speed, on admission patient's state of consciousness and head CT measured on admission hematoma volume, respectively.

  1. Proactive selective response suppression is implemented via the basal ganglia.

    Science.gov (United States)

    Majid, D S Adnan; Cai, Weidong; Corey-Bloom, Jody; Aron, Adam R

    2013-08-14

    In the welter of everyday life, people can stop particular response tendencies without affecting others. A key requirement for such selective suppression is that subjects know in advance which responses need stopping. We hypothesized that proactively setting up and implementing selective suppression relies on the basal ganglia and, specifically, regions consistent with the inhibitory indirect pathway for which there is scant functional evidence in humans. Consistent with this hypothesis, we show, first, that the degree of proactive motor suppression when preparing to stop selectively (indexed by transcranial magnetic stimulation) corresponds to striatal, pallidal, and frontal activation (indexed by functional MRI). Second, we demonstrate that greater striatal activation at the time of selective stopping correlates with greater behavioral selectivity. Third, we show that people with striatal and pallidal volume reductions (those with premanifest Huntington's disease) have both absent proactive motor suppression and impaired behavioral selectivity when stopping. Thus, stopping goals are used to proactively set up specific basal ganglia channels that may then be triggered to implement selective suppression. By linking this suppression to the striatum and pallidum, these results provide compelling functional evidence in humans of the basal ganglia's inhibitory indirect pathway.

  2. Saccade learning with concurrent cortical and subcortical basal ganglia loops

    Directory of Open Access Journals (Sweden)

    Steve eN'guyen

    2014-04-01

    Full Text Available The Basal Ganglia is a central structure involved in multiple cortical and subcortical loops. Some of these loops are believed to be responsible for saccade target selection. We study here how the very specific structural relationships of these saccadic loops can affect the ability of learning spatial and feature-based tasks.We propose a model of saccade generation with reinforcement learning capabilities based onour previous basal ganglia and superior colliculus models. It is structured around the interactions of two parallel cortico-basal loops and one tecto-basal loop. The two cortical loops separately deal with spatial and non-spatial information to select targets in a concurrent way. The subcortical loop is used to make the final target selection leading to the production of thesaccade. These different loops may work in concert or disturb each other regarding reward maximization. Interactions between these loops and their learning capabilities are tested on different saccade tasks.The results show the ability of this model to correctly learn basic target selection based on different criteria (spatial or not. Moreover the model reproduces and explains training dependent express saccades toward targets based on a spatial criterion. Finally, the model predicts that in absence of prefrontal control, the spatial loop should dominate.

  3. Basal ganglia circuit loops, dopamine and motivation: A review and enquiry.

    Science.gov (United States)

    Ikemoto, Satoshi; Yang, Chen; Tan, Aaron

    2015-09-01

    Dopamine neurons located in the midbrain play a role in motivation that regulates approach behavior (approach motivation). In addition, activation and inactivation of dopamine neurons regulate mood and induce reward and aversion, respectively. Accumulating evidence suggests that such motivational role of dopamine neurons is not limited to those located in the ventral tegmental area, but also in the substantia nigra. The present paper reviews previous rodent work concerning dopamine's role in approach motivation and the connectivity of dopamine neurons, and proposes two working models: One concerns the relationship between extracellular dopamine concentration and approach motivation. High, moderate and low concentrations of extracellular dopamine induce euphoric, seeking and aversive states, respectively. The other concerns circuit loops involving the cerebral cortex, basal ganglia, thalamus, epithalamus, and midbrain through which dopaminergic activity alters approach motivation. These models should help to generate hypothesis-driven research and provide insights for understanding altered states associated with drugs of abuse and affective disorders. PMID:25907747

  4. Basal ganglia disorders studied by positron emission tomography

    International Nuclear Information System (INIS)

    Recent development of positron emitting radioligands has made it possible to investigate the alterations of neurotransmitter systems associated with basal ganglia disorders in vivo. The functional integrity of nigro-striatal dopaminergic terminals may be studied with [18F]6-fluoro-L-dopa ([18F]dopa), and striatal dopamine receptor density with suitable PET ligands. [18F]dopa uptake in the striatum (putamen) is markedly reduced in patients with Parkinson's disease (PD). [18F]dopa-PET is capable of detecting sub-clinical nigral dysfunction in asymptomatic patients with familial PD and those who become Parkinsonian on conventional doses of dopamine receptor antagonists. While putamen [18F]dopa uptake is reduced to a similar level in patients with multiple system atrophy (MSA) and PD, caudate [18F] dopa uptake is lower in MSA than PD. However, [18F]dopa PET cannot consistently distinguish MSA from PD because individual ranges of caudate [18F]dopa uptake overlap. D1 and D2 receptor binding is markedly reduced in the striatum (posterior putamen) of MSA patients. Therefore, dopamine receptor imaging is useful for the differential diagnosis of MSA and PD. Similar marked reductions in putamen and caudate [18F]dopa uptake have been observed in patients with progressive supranuclear palsy (PSP). Moderate reductions in D2 receptor binding have been reported in the striatum of PSP patients. The reduction in D2 receptor binding is more prominent in the caudate than putamen. Striatal [18F]dopa uptake is normal or only mildly reduced in patients with dopa responsive dystonia (DRD). D2 receptor binding is markedly reduced in patients with Huntington's disease, while striatal [18F]dopa uptake is normal or mildly reduced. In summary, PET can demonstrate characteristic patterns of disruption of dopaminergic systems associated with basal ganglia disorders. These PET findings are useful in the differential diagnosis of basal ganglia disorders. (J.P.N.) 55 refs

  5. Learning processing in the basal ganglia: a mosaic of broken mirrors.

    Science.gov (United States)

    Da Cunha, Claudio; Wietzikoski, Evellyn Claudia; Dombrowski, Patrícia; Bortolanza, Mariza; Santos, Lucélia Mendes; Boschen, Suelen Lucio; Miyoshi, Edmar

    2009-04-12

    In the present review we propose a model to explain the role of the basal ganglia in sensorimotor and cognitive functions based on a growing body of behavioural, anatomical, physiological, and neurochemical evidence accumulated over the last decades. This model proposes that the body and its surrounding environment are represented in the striatum in a fragmented and repeated way, like a mosaic consisting of the fragmented images of broken mirrors. Each fragment forms a functional unit representing articulated parts of the body with motion properties, objects of the environment which the subject can approach or manipulate, and locations the subject can move to. These units integrate the sensory properties and movements related to them. The repeated and widespread distribution of such units amplifies the combinatorial power of the associations among them. These associations depend on the phasic release of dopamine in the striatum triggered by the saliency of stimuli and will be reinforced by the rewarding consequences of the actions related to them. Dopamine permits synaptic plasticity in the corticostriatal synapses. The striatal units encoding the same stimulus/action send convergent projections to the internal segment of the globus pallidus (GPi) and to the substantia nigra pars reticulata (SNr) that stimulate or hold the action through a thalamus-frontal cortex pathway. According to this model, this is how the basal ganglia select actions based on environmental stimuli and store adaptive associations as nondeclarative memories such as motor skills, habits, and memories formed by Pavlovian and instrumental conditioning. PMID:18977393

  6. Understanding Parkinsonian handwriting through a computational model of basal ganglia.

    Science.gov (United States)

    Gangadhar, Garipelli; Joseph, Denny; Chakravarthy, V Srinivasa

    2008-10-01

    Handwriting in Parkinson's disease (PD) is typically characterized by micrographia, jagged line contour, and unusual fluctuations in pen tip velocity. Although PD handwriting features have been used for diagnostics, they are not based on a signaling model of basal ganglia (BG). In this letter, we present a computational model of handwriting generation that highlights the role of BG. When PD conditions like reduced dopamine and altered dynamics of the subthalamic nucleus and globus pallidus externa subsystems are simulated, the handwriting produced by the model manifested characteristic PD handwriting distortions like micrographia and velocity fluctuations. Our approach to PD modeling is in tune with the perspective that PD is a dynamic disease. PMID:18386983

  7. 基底节性失语%Basal Ganglia Aphasia

    Institute of Scientific and Technical Information of China (English)

    隆昱洲; 柳华; 艾青龙

    2008-01-01

    基底节病变常导致语言功能障碍,其表现彤式复杂,既可出现口语语言障碍,也可出现书面语语言障碍,几乎包括所有失语类型.文章就基底节解剖、基底节失语的定义、特点、机制以及病变部位对语言的影响做了综述.%Basal ganglion lesions often result in language impairment. Its patterns of manifestation are complicated. Patients may either have oral language disorders or written language disorders, which almost includes all types of aphasia, The article reviews the anatomy, definition, feature and mechanisms of basal ganglia aphasia as well as the effect of lesion sites on language.

  8. Idiopathic Basal Ganglia Calcification Presented with Impulse Control Disorder

    Science.gov (United States)

    Sahin, Cem; Levent, Mustafa; Akbaba, Gulhan; Kara, Bilge; Yeniceri, Emine Nese; Inanc, Betul Battaloglu

    2015-01-01

    Primary familial brain calcification (PFBC), also referred to as Idiopathic Basal Ganglia Calcification (IBGC) or “Fahr's disease,” is a clinical condition characterized by symmetric and bilateral calcification of globus pallidus and also basal ganglions, cerebellar nuclei, and other deep cortical structures. It could be accompanied by parathyroid disorder and other metabolic disturbances. The clinical features are dysfunction of the calcified anatomic localization. IBGC most commonly presents with mental damage, convulsion, parkinson-like clinical picture, and neuropsychiatric behavior disorders; however, presentation with impulse control disorder is not a frequent presentation. In the current report, a 43-year-old male patient who has been admitted to psychiatry policlinic with the complaints of aggressive behavior episodes and who has been diagnosed with impulse control disorder and IBGC was evaluated in the light of the literature. PMID:26246920

  9. Novelty encoding by the output neurons of the basal ganglia

    Directory of Open Access Journals (Sweden)

    Mati Joshua

    2010-01-01

    Full Text Available Reinforcement learning models of the basal ganglia have focused on the resemblance of the dopamine signal to the temporal difference error. However the role of the network as a whole is still elusive, in particular whether the output of the basal ganglia encodes only the behavior (actions or it is part of the valuation process. We trained a monkey extensively on a probabilistic conditional task with seven fractal cues predicting rewarding or aversive outcomes (familiar cues. Then in each recording session we added a cue that the monkey had never seen before (new cue and recorded from single units in the Substantia Nigra pars reticulata (SNpr while the monkey was engaged in a task with new cues intermingled within the familiar ones. The monkey learned the association between the new cue and outcome and modified its licking and blinking behavior which became similar to responses to the familiar cues with the same outcome. However, the responses of many SNpr neurons to the new cue exceeded their response to familiar cues even after behavioral learning was completed. This dissociation between behavior and neural activity suggests that the BG output code goes beyond instruction or gating of behavior to encoding of novel cues. Thus, BG output can enable learning at the levels of its target neural networks.

  10. Morphological elucidation of basal ganglia circuits contributing reward prediction

    Directory of Open Access Journals (Sweden)

    Fumino eFujiyama

    2015-02-01

    Full Text Available Electrophysiological studies in monkeys have shown that dopaminergic neurons respond to the reward prediction error. In addition, striatal neurons alter their responsiveness to cortical or thalamic inputs in response to the dopamine signal, via the mechanism of dopamine-regulated synaptic plasticity. These findings have led to the hypothesis that the striatum exhibits synaptic plasticity under the influence of the reward prediction error and conduct reinforcement learning throughout the basal ganglia circuits.The reinforcement learning model is useful; however, the mechanism by which such a process emerges in the basal ganglia needs to be anatomically explained. The actor–critic model has been previously proposed and extended by the existence of role sharing within the striatum, focusing on the striosome/matrix compartments. However, this hypothesis has been difficult to confirm morphologically, partly because of the complex structure of the striosome/matrix compartments. Here, we review recent morphological studies that elucidate the input/output organization of the striatal compartments.

  11. Mephedrone alters basal ganglia and limbic dynorphin systems.

    Science.gov (United States)

    German, Christopher L; Alburges, Mario E; Hoonakker, Amanda J; Fleckenstein, Annette E; Hanson, Glen R

    2014-08-25

    Mephedrone (4-methymethcathinone) is a synthetic cathinone designer drug that disrupts central nervous system (CNS) dopamine (DA) signaling. Numerous central neuropeptide systems reciprocally interact with dopaminergic neurons to provide regulatory counterbalance, and are altered by aberrant DA activity associated with stimulant exposure. Endogenous opioid neuropeptides are highly concentrated within dopaminergic CNS regions and facilitate many rewarding and aversive properties associated with drug use. Dynorphin, an opioid neuropeptide and kappa receptor agonist, causes dysphoria and aversion to drug consumption through signaling within the basal ganglia and limbic systems, which is affected by stimulants. This study evaluated how mephedrone alters basal ganglia and limbic system dynorphin content, and the role of DA signaling in these changes. Repeated mephedrone administrations (4 × 25 mg/kg/injection, 2-h intervals) selectively increased dynorphin content throughout the dorsal striatum and globus pallidus, decreased dynorphin content within the frontal cortex, and did not alter dynorphin content within most limbic system structures. Pretreatment with D1 -like (SCH-23380) or D2 -like (eticlopride) antagonists blocked mephedrone-induced changes in dynorphin content in most regions examined, indicating altered dynorphin activity is a consequence of excessive DA signaling. Synapse, 2014. © 2014 Wiley Periodicals, Inc.

  12. Chorea due to basal ganglia involvement in a uremic diabetic patient

    Directory of Open Access Journals (Sweden)

    Faik Ilik

    2014-04-01

    Full Text Available Syndromes associated with acute bilateral lesions of the basal ganglia in diabetic uremic patients are uncommon. Uremic encephalopathy is typical of patients showing cortical involvement, with symptoms including confusion, seizures, tremors, or myoclonus. Whenever basal ganglia are anatomically involved, movement disorders arise, including chorea. In this article we present a case with basal ganglia involvement in a uremic diabetic patient causes chorea because of rare presentation. [Cukurova Med J 2014; 39(2.000: 353-356

  13. Relationship between obsessive-compulsive disorders and diseases affecting primarily the basal ganglia

    Directory of Open Access Journals (Sweden)

    Maia Alex S. S. Freire

    1999-01-01

    Full Text Available Obsessive-compulsive disorder (OCD has been reported in association with some neurological diseases that affect the basal ganglia such as Tourette's syndrome, Sydenham's chorea, Parkinson's disease, and Huntington's disease. Furthermore, studies such as neuroimaging, suggest a role of the basal ganglia in the pathophysiology of OCD. The aim of this paper is to describe the association of OCD and several neurologic disorders affecting the basal ganglia, report the existing evidences of the role of the basal ganglia in the pathophysiology of OCD, and analyze the mechanisms probably involved in this pathophysiology.

  14. Traumatic bilateral basal ganglia bleed: A report of rare two cases and review of the literature

    Science.gov (United States)

    Kankane, Vivek Kumar; Gupta, Tarun Kumar; Jaiswal, Gaurav

    2016-01-01

    Traumatic basal ganglia hemorrhage (TBGH) is relatively uncommon. Bilateral basal ganglia hematoma after trauma is extremely rare and is limited to case reports. We report two cases of traumatic bilateral basal ganglia hemorrhage and review the literature in brief. Both cases were managed conservatively. The general incidence of TBGH is reported between 2.4% and 3% of closed head injury. However, the incidence is higher in postmortem studies (9.8%). Bilateral traumatic basal ganglia hematoma is extremely rare. Descriptions are limited to case reports.

  15. Exploring the cognitive and motor functions of the basal ganglia: an integrative review of computational cognitive neuroscience models

    OpenAIRE

    Sebastien Helie; Srinivasa Chakravarthy; Moustafa, Ahmed A.

    2013-01-01

    Many computational models of the basal ganglia have been proposed over the past twenty-five years. While computational neuroscience models have focused on closely matching the neurobiology of the basal ganglia, computational cognitive neuroscience models have focused on how the basal ganglia can be used to implement cognitive and motor functions. This review article focuses on computational cognitive neuroscience models of the basal ganglia and how they use the neuroanatomy of the basal gangl...

  16. Characteristics of basal ganglia aphasia after stroke and the rehabilitative interventions

    Institute of Scientific and Technical Information of China (English)

    Yating Kong; Xifeng Pan; Qimei Zhang

    2006-01-01

    OBJECTIVE: To introduce the characteristics of basal ganglia aphasia after stroke and the rehabilitative interventions.DATA SOURCES: Articles related to stroke, subcortical aphasia, basal ganglia aphasia and language rehabilitation published in Chinese from January 1988 to December 2005 were searched in Chinese journal full-text database (CJFD) using the keywords of"stroke, basal ganglia aphasia, language rehabilitation" in Chinese. Meanwhile, English articles about aphasia published from January 1982 to December 2005 were searched in and Pubmed database. Besides, several books associated with the contents were looked through manually.STUDY SELECTION: The data were checked primarily, the articles about the pathomechanism and neurolinguistic characteristics of basal ganglia aphasia, diagnostic methods of aphasia and language rehabilitation were selected, and those had no obvious relation with the above contents were excluded.Inclusive criteria: literatures explain the clinical characteristics of basal ganglia aphasia, neurolinguistic pathogenesis and methods of rehabilitation therapy in details. The repetitive studies were excluded.DATA EXTRACTION: Totally 95 literatures about basal ganglia aphasia were collected, including 31 about the clinical characteristics of basal ganglia aphasia, 45 about its neurolinguistic pathogenesis, 5 about the evaluation and classification of aphasia, and 14 about its rehabilitation therapy. Thirty accorded with the inclusive criteria were used for review, and the other 65 were excluded.DATA SYNTHESIS: Concisely introduced the definition, past investigation of basal ganglia aphasia after stroke, then dwelled on the multiplicity neurolinguistics characteristics. Aphasia evaluation was dependent upon clinical aphasic symptoms. The relationship between symptom and focus of infection was explored, and the mechanism of pathosis language behavior on basal ganglia aphasia patients was understood to provide consequence data that could

  17. Basal ganglia contributions to motor control: a vigorous tutor.

    Science.gov (United States)

    Turner, Robert S; Desmurget, Michel

    2010-12-01

    The roles of the basal ganglia (BG) in motor control are much debated. Many influential hypotheses have grown from studies in which output signals of the BG were not blocked, but pathologically disturbed. A weakness of that approach is that the resulting behavioral impairments reflect degraded function of the BG per se mixed together with secondary dysfunctions of BG-recipient brain areas. To overcome that limitation, several studies have focused on the main skeletomotor output region of the BG, the globus pallidus internus (GPi). Using single-cell recording and inactivation protocols these studies provide consistent support for two hypotheses: the BG modulates movement performance ('vigor') according to motivational factors (i.e. context-specific cost/reward functions) and the BG contributes to motor learning. Results from these studies also add to the problems that confront theories positing that the BG selects movement, inhibits unwanted motor responses, corrects errors on-line, or stores and produces well-learned motor skills. PMID:20850966

  18. Basal ganglia outputs map instantaneous position coordinates during behavior.

    Science.gov (United States)

    Barter, Joseph W; Li, Suellen; Sukharnikova, Tatyana; Rossi, Mark A; Bartholomew, Ryan A; Yin, Henry H

    2015-02-11

    The basal ganglia (BG) are implicated in many movement disorders, yet how they contribute to movement remains unclear. Using wireless in vivo recording, we measured BG output from the substantia nigra pars reticulata (SNr) in mice while monitoring their movements with video tracking. The firing rate of most nigral neurons reflected Cartesian coordinates (either x- or y-coordinates) of the animal's head position during movement. The firing rates of SNr neurons are either positively or negatively correlated with the coordinates. Using an egocentric reference frame, four types of neurons can be classified: each type increases firing during movement in a particular direction (left, right, up, down), and decreases firing during movement in the opposite direction. Given the high correlation between the firing rate and the x and y components of the position vector, the movement trajectory can be reconstructed from neural activity. Our results therefore demonstrate a quantitative and continuous relationship between BG output and behavior. Thus, a steady BG output signal from the SNr (i.e., constant firing rate) is associated with the lack of overt movement, when a stable posture is maintained by structures downstream of the BG. Any change in SNr firing rate is associated with a change in position (i.e., movement). We hypothesize that the SNr output quantitatively determines the direction, velocity, and amplitude of voluntary movements. By changing the reference signals to downstream position control systems, the BG can produce transitions in body configurations and initiate actions.

  19. Quantitation of the human basal ganglia with Positron Emission Tomography

    International Nuclear Information System (INIS)

    The accurate measurement of the concentration of a radioisotope in small structures with PET requires a correction for quantitation loss due to the partial volume effect and the effect of scattered radiation. To evaluate errors associated with measures in the human basal ganglia (BG) we have built a unilateral model of the BG that we have inserted in a 20 cm cylinder. The recovery coefficient (RC = measured activity/true activity) for our BG phantom has been measured on a CTI tomograph (model 931-08/12) with different background concentrations (contrast) and at different axial locations in the gantry. The BG was visualized on 4 or 5 slices depending on its position in the gantry and on the contrast used. The RC was 0.75 with no background (contrast equal to 1.0). Increasing the relative radioactivity concentration in the background increased the RC from 0.75 to 2.00 when the contrast was -0.7 (BG 2). These results show that accurate RC correction depends not only on the volume of the structure but also on its contrast with its surroundings as well as on the selection of the ROI. They also demonstrate that the higher the contrast the more sensitive to axial positioning PET measurements in the BG are. These data provide us with some information about the variability of PET measurements in small structure like the BG and we have proposed some strategies to improve the reproducibility. 18 refs., 3 figs., 5 tabs

  20. Modeling basal ganglia for understanding Parkinsonian reaching movements.

    Science.gov (United States)

    Magdoom, K N; Subramanian, D; Chakravarthy, V S; Ravindran, B; Amari, Shun-Ichi; Meenakshisundaram, N

    2011-02-01

    We present a computational model that highlights the role of basal ganglia (BG) in generating simple reaching movements. The model is cast within the reinforcement learning (RL) framework with correspondence between RL components and neuroanatomy as follows: dopamine signal of substantia nigra pars compacta as the temporal difference error, striatum as the substrate for the critic, and the motor cortex as the actor. A key feature of this neurobiological interpretation is our hypothesis that the indirect pathway is the explorer. Chaotic activity, originating from the indirect pathway part of the model, drives the wandering, exploratory movements of the arm. Thus, the direct pathway subserves exploitation, while the indirect pathway subserves exploration. The motor cortex becomes more and more independent of the corrective influence of BG as training progresses. Reaching trajectories show diminishing variability with training. Reaching movements associated with Parkinson's disease (PD) are simulated by reducing dopamine and degrading the complexity of indirect pathway dynamics by switching it from chaotic to periodic behavior. Under the simulated PD conditions, the arm exhibits PD motor symptoms like tremor, bradykinesia and undershooting. The model echoes the notion that PD is a dynamical disease. PMID:21105828

  1. Basal ganglia cholinergic and dopaminergic function in progressive supranuclear palsy.

    Science.gov (United States)

    Warren, Naomi M; Piggott, Margaret A; Greally, Elizabeth; Lake, Michelle; Lees, Andrew J; Burn, David J

    2007-08-15

    Progressive Supranuclear Palsy (PSP) is a progressive neurodegenerative disorder. In contrast to Parkinson's disease (PD) and dementia with Lewy bodies (DLB), replacement therapy with dopaminergic and cholinergic agents in PSP has been disappointing. The neurochemical basis for this is unclear. Our objective was to measure dopaminergic and cholinergic receptors in the basal ganglia of PSP and control brains. We measured, autoradiographically, dopaminergic (dopamine transporter, 125I PE2I and dopamine D2 receptors, 125I epidepride) and cholinergic (nicotinic alpha4beta2 receptors, 125I 5IA85380 and muscarinic M1 receptors, 3H pirenzepine) parameters in the striatum and pallidum of pathologically confirmed PSP cases (n=15) and controls (n=32). In PSP, there was a marked loss of dopamine transporter and nicotinic alpha4beta2 binding in the striatum and pallidum, consistent with loss of nigrostriatal neurones. Striatal D2 receptors were increased in the caudate and muscarinic M1 receptors were unchanged compared with controls. These results do not account for the poor response to dopaminergic and cholinergic replacement therapies in PSP, and suggest relative preservation of postsynaptic striatal projection neurones bearing D2/M1 receptors. PMID:17534953

  2. Parallel basal ganglia circuits for voluntary and automatic behaviour to reach rewards.

    Science.gov (United States)

    Kim, Hyoung F; Hikosaka, Okihide

    2015-07-01

    The basal ganglia control body movements, value processing and decision-making. Many studies have shown that the inputs and outputs of each basal ganglia structure are topographically organized, which suggests that the basal ganglia consist of separate circuits that serve distinct functions. A notable example is the circuits that originate from the rostral (head) and caudal (tail) regions of the caudate nucleus, both of which target the superior colliculus. These two caudate regions encode the reward values of visual objects differently: flexible (short-term) values by the caudate head and stable (long-term) values by the caudate tail. These value signals in the caudate guide the orienting of gaze differently: voluntary saccades by the caudate head circuit and automatic saccades by the caudate tail circuit. Moreover, separate groups of dopamine neurons innervate the caudate head and tail and may selectively guide the flexible and stable learning/memory in the caudate regions. Studies focusing on manual handling of objects also suggest that rostrocaudally separated circuits in the basal ganglia control the action differently. These results suggest that the basal ganglia contain parallel circuits for two steps of goal-directed behaviour: finding valuable objects and manipulating the valuable objects. These parallel circuits may underlie voluntary behaviour and automatic skills, enabling animals (including humans) to adapt to both volatile and stable environments. This understanding of the functions and mechanisms of the basal ganglia parallel circuits may inform the differential diagnosis and treatment of basal ganglia disorders. PMID:25981958

  3. Focal expression of mutant huntingtin in the songbird basal ganglia disrupts cortico-basal ganglia networks and vocal sequences.

    Science.gov (United States)

    Tanaka, Masashi; Singh Alvarado, Jonnathan; Murugan, Malavika; Mooney, Richard

    2016-03-22

    The basal ganglia (BG) promote complex sequential movements by helping to select elementary motor gestures appropriate to a given behavioral context. Indeed, Huntington's disease (HD), which causes striatal atrophy in the BG, is characterized by hyperkinesia and chorea. How striatal cell loss alters activity in the BG and downstream motor cortical regions to cause these disorganized movements remains unknown. Here, we show that expressing the genetic mutation that causes HD in a song-related region of the songbird BG destabilizes syllable sequences and increases overall vocal activity, but leave the structure of individual syllables intact. These behavioral changes are paralleled by the selective loss of striatal neurons and reduction of inhibitory synapses on pallidal neurons that serve as the BG output. Chronic recordings in singing birds revealed disrupted temporal patterns of activity in pallidal neurons and downstream cortical neurons. Moreover, reversible inactivation of the cortical neurons rescued the disorganized vocal sequences in transfected birds. These findings shed light on a key role of temporal patterns of cortico-BG activity in the regulation of complex motor sequences and show how a genetic mutation alters cortico-BG networks to cause disorganized movements. PMID:26951661

  4. Potential mechanisms for imperfect synchronization in parkinsonian basal ganglia.

    Directory of Open Access Journals (Sweden)

    Choongseok Park

    Full Text Available Neural activity in the brain of parkinsonian patients is characterized by the intermittently synchronized oscillatory dynamics. This imperfect synchronization, observed in the beta frequency band, is believed to be related to the hypokinetic motor symptoms of the disorder. Our study explores potential mechanisms behind this intermittent synchrony. We study the response of a bursting pallidal neuron to different patterns of synaptic input from subthalamic nucleus (STN neuron. We show how external globus pallidus (GPe neuron is sensitive to the phase of the input from the STN cell and can exhibit intermittent phase-locking with the input in the beta band. The temporal properties of this intermittent phase-locking show similarities to the intermittent synchronization observed in experiments. We also study the synchronization of GPe cells to synaptic input from the STN cell with dependence on the dopamine-modulated parameters. Earlier studies showed how the strengthening of dopamine-modulated coupling may lead to transitions from non-synchronized to partially synchronized dynamics, typical in Parkinson's disease. However, dopamine also affects the cellular properties of neurons. We show how the changes in firing patterns of STN neuron due to the lack of dopamine may lead to transition from a lower to a higher coherent state, roughly matching the synchrony levels observed in basal ganglia in normal and parkinsonian states. The intermittent nature of the neural beta band synchrony in Parkinson's disease is achieved in the model due to the interplay of the timing of STN input to pallidum and pallidal neuronal dynamics, resulting in sensitivity of pallidal output to the phase of the arriving STN input. Thus the mechanism considered here (the change in firing pattern of subthalamic neurons through the dopamine-induced change of membrane properties may be one of the potential mechanisms responsible for the generation of the intermittent synchronization

  5. Refractory epilepsy and basal ganglia: the role of seizure frequency

    Energy Technology Data Exchange (ETDEWEB)

    Bouilleret, V.; Trebossen, R.; Mantzerides, M.; Semah, F.; Ribeiro, M.J. [Service Hospitalier Frederic Joliot, I2BM/DSV, CEA, 91 - Orsay (France); Bouilleret, V. [CHU Bicetre, Unite de Neurophysiologie et d' Epileptologie, AP-HP, 75 - Paris (France); Chassoux, F. [Hopital Saint Anne, Service de Neurochirurgie, 75 - Paris (France); Biraben, A. [CHU, Service de Neurologie, Hopital Pontchaillou, 35 - Rennes (France)

    2008-02-15

    Objectives. - A decrease of [{sup 18}F]Fluoro-L-DOPA uptake in basal ganglia (B.G.) was recently reported in medically refractory epilepsy. The purpose of this study was to assess the involvement of dopaminergic neurotransmission in refractory Temporal Lobe Epilepsy (T.L.E.) and its relationship to glucose metabolism and morphological changes. Methods. - Twelve T.L.E. patients were studied using [{sup 18}F]FDG PET, [{sup 18}F]Fluoro-L-DOPA PET and MRI and compared with healthy control volunteers. Morphological cerebral changes were assessed using Voxel-Based Morphometry (V.B.M.). Student t test statistical maps of functional and morphological differences between patients and controls were obtained using a general linear model. Results. - In T.L.E. patients, [{sup 18}F]Fluoro-L-DOPA uptake was reduced to the same extent in caudate and putamen in both cerebral hemispheres as well as in the substantia nigra (S.N.). These dopaminergic functional alterations occurred without any glucose metabolism changes in these areas. The only mild morphological abnormality was found in striatal regions without any changes in the S.N.. Conclusion. - The present study provides support for dopaminergic neurotransmission involvement in T.L.E.. The discrepancies between G.M.V. atrophy and the pattern of [{sup 18}F]Fluoro-L-DOPA suggest that B.G. involvement is not related to structural subcortical abnormalities. A functional decrease can be ruled out as there was no change of the glycolytic pathway metabolism in these areas. (authors)

  6. Endoscopic considerations treating hydrocephalus caused by basal ganglia and large thalamic tumors

    Directory of Open Access Journals (Sweden)

    Jonathan Roth

    2015-01-01

    Conclusions: Endoscopic surgery may potentially play a significant role in the initial management of patients with large basal ganglia and large thalamic tumors causing obstructive hydrocephalus. Technical nuances and individualized goals are crucial for optimal outcomes.

  7. Bilateral symmetrical basal ganglia and thalamic lesions in children: an update (2015)

    Energy Technology Data Exchange (ETDEWEB)

    Zuccoli, Giulio [Children' s Hospital of Pittsburgh of UPMC, Section of Neuroradiology, Pittsburgh, PA (United States); Yannes, Michael Paul [University of Pittsburgh School of Medicine, Department of Radiology, Pittsburgh, PA (United States); Nardone, Raffaele [Paracelsus Medical University, Department of Neurology, Christian Doppler Klinik, Salzburg (Austria); Bailey, Ariel [West Virginia University, Department of Radiology, Morgantown, WV (United States); Goldstein, Amy [Children' s Hospital of Pittsburgh of UPMC, Department of Neurology, Section of Metabolic Disorders and Neurogenetics, Pittsburgh, PA (United States)

    2015-10-15

    In children, many inherited or acquired neurological disorders may cause bilateral symmetrical signal intensity alterations in the basal ganglia and thalami. A literature review was aimed at assisting neuroradiologists, neurologists, infectious diseases specialists, and pediatricians to provide further understanding into the clinical and neuroimaging features in pediatric patients presenting with bilateral symmetrical basal ganglia and thalamic lesions on magnetic resonance imaging (MRI). We discuss hypoxic-ischemic, toxic, infectious, immune-mediated, mitochondrial, metabolic, and neurodegenerative disorders affecting the basal ganglia and thalami. Recognition and correct evaluation of basal ganglia abnormalities, together with a proper neurological examination and laboratory findings, may enable the identification of each of these clinical entities and lead to earlier diagnosis. (orig.)

  8. Bilateral symmetrical basal ganglia and thalamic lesions in children: an update (2015)

    International Nuclear Information System (INIS)

    In children, many inherited or acquired neurological disorders may cause bilateral symmetrical signal intensity alterations in the basal ganglia and thalami. A literature review was aimed at assisting neuroradiologists, neurologists, infectious diseases specialists, and pediatricians to provide further understanding into the clinical and neuroimaging features in pediatric patients presenting with bilateral symmetrical basal ganglia and thalamic lesions on magnetic resonance imaging (MRI). We discuss hypoxic-ischemic, toxic, infectious, immune-mediated, mitochondrial, metabolic, and neurodegenerative disorders affecting the basal ganglia and thalami. Recognition and correct evaluation of basal ganglia abnormalities, together with a proper neurological examination and laboratory findings, may enable the identification of each of these clinical entities and lead to earlier diagnosis. (orig.)

  9. Actor-critic models of the basal ganglia: new anatomical and computational perspectives.

    Science.gov (United States)

    Joel, Daphna; Niv, Yael; Ruppin, Eytan

    2002-01-01

    A large number of computational models of information processing in the basal ganglia have been developed in recent years. Prominent in these are actor-critic models of basal ganglia functioning, which build on the strong resemblance between dopamine neuron activity and the temporal difference prediction error signal in the critic, and between dopamine-dependent long-term synaptic plasticity in the striatum and learning guided by a prediction error signal in the actor. We selectively review several actor-critic models of the basal ganglia with an emphasis on two important aspects: the way in which models of the critic reproduce the temporal dynamics of dopamine firing, and the extent to which models of the actor take into account known basal ganglia anatomy and physiology. To complement the efforts to relate basal ganglia mechanisms to reinforcement learning (RL), we introduce an alternative approach to modeling a critic network, which uses Evolutionary Computation techniques to 'evolve' an optimal RL mechanism, and relate the evolved mechanism to the basic model of the critic. We conclude our discussion of models of the critic by a critical discussion of the anatomical plausibility of implementations of a critic in basal ganglia circuitry, and conclude that such implementations build on assumptions that are inconsistent with the known anatomy of the basal ganglia. We return to the actor component of the actor-critic model, which is usually modeled at the striatal level with very little detail. We describe an alternative model of the basal ganglia which takes into account several important, and previously neglected, anatomical and physiological characteristics of basal ganglia-thalamocortical connectivity and suggests that the basal ganglia performs reinforcement-biased dimensionality reduction of cortical inputs. We further suggest that since such selective encoding may bias the representation at the level of the frontal cortex towards the selection of rewarded

  10. Basal ganglia dysfunction in idiopathic REM sleep behaviour disorder parallels that in early Parkinson's disease.

    Science.gov (United States)

    Rolinski, Michal; Griffanti, Ludovica; Piccini, Paola; Roussakis, Andreas A; Szewczyk-Krolikowski, Konrad; Menke, Ricarda A; Quinnell, Timothy; Zaiwalla, Zenobia; Klein, Johannes C; Mackay, Clare E; Hu, Michele T M

    2016-08-01

    SEE POSTUMA DOI101093/AWW131 FOR A SCIENTIFIC COMMENTARY ON THIS ARTICLE: Resting state functional magnetic resonance imaging dysfunction within the basal ganglia network is a feature of early Parkinson's disease and may be a diagnostic biomarker of basal ganglia dysfunction. Currently, it is unclear whether these changes are present in so-called idiopathic rapid eye movement sleep behaviour disorder, a condition associated with a high rate of future conversion to Parkinson's disease. In this study, we explore the utility of resting state functional magnetic resonance imaging to detect basal ganglia network dysfunction in rapid eye movement sleep behaviour disorder. We compare these data to a set of healthy control subjects, and to a set of patients with established early Parkinson's disease. Furthermore, we explore the relationship between resting state functional magnetic resonance imaging basal ganglia network dysfunction and loss of dopaminergic neurons assessed with dopamine transporter single photon emission computerized tomography, and perform morphometric analyses to assess grey matter loss. Twenty-six patients with polysomnographically-established rapid eye movement sleep behaviour disorder, 48 patients with Parkinson's disease and 23 healthy control subjects were included in this study. Resting state networks were isolated from task-free functional magnetic resonance imaging data using dual regression with a template derived from a separate cohort of 80 elderly healthy control participants. Resting state functional magnetic resonance imaging parameter estimates were extracted from the study subjects in the basal ganglia network. In addition, eight patients with rapid eye movement sleep behaviour disorder, 10 with Parkinson's disease and 10 control subjects received (123)I-ioflupane single photon emission computerized tomography. We tested for reduction of basal ganglia network connectivity, and for loss of tracer uptake in rapid eye movement sleep

  11. Acute Psychosis Associated with Subcortical Stroke: Comparison between Basal Ganglia and Mid-Brain Lesions

    OpenAIRE

    Aaron McMurtray; Ben Tseng; Natalie Diaz; Julia Chung; Bijal Mehta; Erin Saito

    2014-01-01

    Acute onset of psychosis in an older or elderly individual without history of previous psychiatric disorders should prompt a thorough workup for neurologic causes of psychiatric symptoms. This report compares and contrasts clinical features of new onset of psychotic symptoms between two patients, one with an acute basal ganglia hemorrhagic stroke and another with an acute mid-brain ischemic stroke. Delusions and hallucinations due to basal ganglia lesions are theorized to develop as a result ...

  12. Minimizing Human Intervention in the Development of Basal Ganglia-Inspired Robot Control

    OpenAIRE

    F. Montes-Gonzalez; Prescott, T.J; Negrete-Martinez, J.

    2007-01-01

    A biologically inspired mechanism for robot action selection, based on the vertebrate basal ganglia, has been previously presented (Prescott et al. 2006, Montes Gonzalez et al. 2000). In this model the task confronting the robot is decomposed into distinct behavioural modules that integrate information from multiple sensors and internal state to form ‘salience’ signals. These signals are provided as inputs to a computational model of the basal ganglia whose intrinsic processes cause the selec...

  13. Single-voxel proton MR spectroscopy of the basal ganglia in patients with neurofibromatosis type 1

    International Nuclear Information System (INIS)

    To demonstrate the proton MR spectroscopic characteristics of non-neoplastic focal basal ganglia lesions with high signal intensity on long TR MR images in patients with neurofibromatosis type 1(NF-1), and to compare them with those of normal-appearing basal ganglia in patients without focal lesions. Materials and Methods: Single-voxel proton MR spectroscopy was performed in six patients with NF-1 from two families(three with and three without non-neoplastic focal brain lesions). All six individual spectra were obtained from basal ganglia with voxel sizes of about 1 x 1 x 1 cm, three from focal pallidal lesions in patients with focal lesions and three from normal-appearing basal ganglia in patients without focal lesions. Spectra were acquired using a 1.5T clinical MR imager and stimulated echo acquisition mode sequence, with the following parameters: 30 ms of echo time, 13.7ms of mixing time, and 2560 ms of repetition time. Zero and first-order phase correction was performed. Results :N-acetyl aspartate(NAA)/creatine(Cr) ratios were similar between focal basal ganglia lesions and normal-appearing basal ganglia, though the former showed slightly lower choline(Cho)/Cr ratios and slightly higher NAA/Cho ratios than the latter. Relatively enhanced resonances around 3.75 ppm, assigned as glutamate/glutamine, were observed in the spectra of three focal lesions. Lipid resonances around slightly different positions were observed in all six patients, regardless of the presence or absence of focal lesions. Conclusion : Slightly decreased Cho levels and relatively enhanced glutamate/glutamine resonances are thought to characterize the focal basal ganglia lesions of NF-1. Different mobile lipids appear to be present in the basal ganglia of NF-1 patients, regardless of the presence of focal lesions

  14. Acute Chorea Characterized by Bilateral Basal Ganglia Lesions in a Patient with Diabetic Nephropathy

    OpenAIRE

    İbrahim DOĞAN; Serdar KAHVECİOĞLU; Kurtoğlu, Ünal; YILDIZ, DEMET; Abdulmecit YILDIZ

    2015-01-01

    The syndrome of acute bilateral basal ganglia lesions associated with uremia presents with parkinsonism, altered mental status, and chorea in association with specific imaging findings in the basal ganglia. It is an uncommon syndrome seen generally in patients with diabetes mellitus and renal failure. We report a male patient with diabetes mellitus who received hemodialysis treatment 3 days a week for 5 years and suffered from choreic movements developed suddenly and associated with bilateral...

  15. Electrophysiological Evidences of Organization of Cortical Motor Information in the Basal Ganglia

    Directory of Open Access Journals (Sweden)

    Hirokazu Iwamuro

    2011-05-01

    Full Text Available During the last two decades, the many developments in the treatment of movement disorders such as Parkinson disease and dystonia have enhanced our understanding on organization of the basal ganglia, and this knowledge has led to other advances in the field. According to many electrophysiological and anatomical findings, it is considered that motor information from different cortical areas is processed through several cortico-basal ganglia loops principally in a parallel fashion and somatotopy from each cortical area is also well preserved in each loop. Moreover, recent studies suggest that not only the parallel processing but also some convergence of information occur through the basal ganglia. Information from cortical areas whose functions are close to each other tends to converge in the basal ganglia. The cortico-basal ganglia loops should be comprehended more as a network rather than as separated subdivisions. However, the functions of this convergence still remain unknown. It is important even for clinical doctors to be well informed about this kind of current knowledge because some symptoms of movement disorders may be explained by disorganization of the information network in the basal ganglia.

  16. Deep Brain Stimulation for Movement Disorders of Basal Ganglia Origin: Restoring Function or Functionality?

    Science.gov (United States)

    Wichmann, Thomas; DeLong, Mahlon R

    2016-04-01

    Deep brain stimulation (DBS) is highly effective for both hypo- and hyperkinetic movement disorders of basal ganglia origin. The clinical use of DBS is, in part, empiric, based on the experience with prior surgical ablative therapies for these disorders, and, in part, driven by scientific discoveries made decades ago. In this review, we consider anatomical and functional concepts of the basal ganglia relevant to our understanding of DBS mechanisms, as well as our current understanding of the pathophysiology of two of the most commonly DBS-treated conditions, Parkinson's disease and dystonia. Finally, we discuss the proposed mechanism(s) of action of DBS in restoring function in patients with movement disorders. The signs and symptoms of the various disorders appear to result from signature disordered activity in the basal ganglia output, which disrupts the activity in thalamocortical and brainstem networks. The available evidence suggests that the effects of DBS are strongly dependent on targeting sensorimotor portions of specific nodes of the basal ganglia-thalamocortical motor circuit, that is, the subthalamic nucleus and the internal segment of the globus pallidus. There is little evidence to suggest that DBS in patients with movement disorders restores normal basal ganglia functions (e.g., their role in movement or reinforcement learning). Instead, it appears that high-frequency DBS replaces the abnormal basal ganglia output with a more tolerable pattern, which helps to restore the functionality of downstream networks. PMID:26956115

  17. Dopaminergic Control of the Exploration-Exploitation Trade-Off via the Basal Ganglia

    Science.gov (United States)

    Humphries, Mark D.; Khamassi, Mehdi; Gurney, Kevin

    2012-01-01

    We continuously face the dilemma of choosing between actions that gather new information or actions that exploit existing knowledge. This “exploration-exploitation” trade-off depends on the environment: stability favors exploiting knowledge to maximize gains; volatility favors exploring new options and discovering new outcomes. Here we set out to reconcile recent evidence for dopamine’s involvement in the exploration-exploitation trade-off with the existing evidence for basal ganglia control of action selection, by testing the hypothesis that tonic dopamine in the striatum, the basal ganglia’s input nucleus, sets the current exploration-exploitation trade-off. We first advance the idea of interpreting the basal ganglia output as a probability distribution function for action selection. Using computational models of the full basal ganglia circuit, we showed that, under this interpretation, the actions of dopamine within the striatum change the basal ganglia’s output to favor the level of exploration or exploitation encoded in the probability distribution. We also found that our models predict striatal dopamine controls the exploration-exploitation trade-off if we instead read-out the probability distribution from the target nuclei of the basal ganglia, where their inhibitory input shapes the cortical input to these nuclei. Finally, by integrating the basal ganglia within a reinforcement learning model, we showed how dopamine’s effect on the exploration-exploitation trade-off could be measurable in a forced two-choice task. These simulations also showed how tonic dopamine can appear to affect learning while only directly altering the trade-off. Thus, our models support the hypothesis that changes in tonic dopamine within the striatum can alter the exploration-exploitation trade-off by modulating the output of the basal ganglia. PMID:22347155

  18. Selection of cortical dynamics for motor behaviour by the basal ganglia.

    Science.gov (United States)

    Mannella, Francesco; Baldassarre, Gianluca

    2015-12-01

    The basal ganglia and cortex are strongly implicated in the control of motor preparation and execution. Re-entrant loops between these two brain areas are thought to determine the selection of motor repertoires for instrumental action. The nature of neural encoding and processing in the motor cortex as well as the way in which selection by the basal ganglia acts on them is currently debated. The classic view of the motor cortex implementing a direct mapping of information from perception to muscular responses is challenged by proposals viewing it as a set of dynamical systems controlling muscles. Consequently, the common idea that a competition between relatively segregated cortico-striato-nigro-thalamo-cortical channels selects patterns of activity in the motor cortex is no more sufficient to explain how action selection works. Here, we contribute to develop the dynamical view of the basal ganglia-cortical system by proposing a computational model in which a thalamo-cortical dynamical neural reservoir is modulated by disinhibitory selection of the basal ganglia guided by top-down information, so that it responds with different dynamics to the same bottom-up input. The model shows how different motor trajectories can so be produced by controlling the same set of joint actuators. Furthermore, the model shows how the basal ganglia might modulate cortical dynamics by preserving coarse-grained spatiotemporal information throughout cortico-cortical pathways.

  19. Exercise-induced changes in basal ganglia volume and cognition in older adults.

    Science.gov (United States)

    Niemann, C; Godde, B; Staudinger, U M; Voelcker-Rehage, C

    2014-12-01

    Physical activity has been demonstrated to diminish age-related brain volume shrinkage in several brain regions accompanied by a reduction of age-related decline in cognitive functions. Most studies investigated the impact of cardiovascular fitness or training. Other types of fitness or training are less well investigated. In addition, little is known about exercise effects on volume of the basal ganglia, which, however, are involved in motor activities and cognitive functioning. In the current study (1) we examined the relationships of individual cardiovascular and motor fitness levels with the volume of the basal ganglia (namely caudate, putamen, and globus pallidus) and selected cognitive functions (executive control, perceptual speed). (2) We investigated the effect of 12-month training interventions (cardiovascular and coordination training, control group stretching and relaxation) on the volume of the respective basal ganglia nuclei. Results revealed that motor fitness but not cardiovascular fitness was positively related with the volume of the putamen and the globus pallidus. Additionally, a moderating effect of the volume of the basal ganglia (as a whole, but also separately for putamen and globus pallidus) on the relationship between motor fitness and executive function was revealed. Coordination training increased caudate and globus pallidus volume. We provide evidence that coordinative exercise seems to be a favorable leisure activity for older adults that has the potential to improve volume of the basal ganglia. PMID:25255932

  20. Acute bilateral basal ganglia lesions in diabetic uraemia: diffusion-weighted MRI

    International Nuclear Information System (INIS)

    We studied four patients with diabetes mellitus and chronic renal failure who developed sudden choreic movement disorders. The clinical manifestations, laboratory findings, MR imaging findings, and clinical outcome in each patient were evaluated. All four patients had long-term diabetes mellitus and severe azotaemia. Brain MR findings consisted of bilateral symmetric basal ganglia lesions, with decreased signal intensity on T1-weighted images and increased signal intensity on T2-weighted images. All three patients who underwent diffusion-weighted MR imaging (DWI) showed signal intensities similar to those of the surroundings in regions corresponding to increased signal intensity on T2-weighted images, with slightly increased apparent diffusion coefficient (ADC) values. Two of the patients showed small focal areas of restricted diffusion within the basal ganglia lesions. After haemodialysis, follow-up MR imaging in all patients demonstrated that the basal ganglia lesions had regressed markedly, with some residual changes. The movement disorders also improved in all patients. A syndrome associated with acute bilateral basal ganglia lesions in diabetic uraemic patients is rare, with reversible changes demonstrated by clinical and imaging findings. DWI showed that the bilateral basal ganglia lesions in this syndrome were primarily vasogenic in origin, although there were small foci of cytotoxic oedema within the lesions. (orig.)

  1. Acute bilateral basal ganglia lesions in diabetic uraemia: diffusion-weighted MRI

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Eun Ja; Park, Chan Sup [Kwandong University, College of Medicine, Department of Radiology, Myongji Hospital, Koyang-City, Gyunggi-Do (Korea); Park, Jong-Ho [Myongji Hospital, Kwandong University, College of Medicine, Department of Neurology, Koyang (Korea); Ihn, Yon kwon; Kim, Young Joo [The Catholic University of Korea, Department of Radiology, Seoul (Korea); Lee, Seon Kyu [University of Toronto, Department of Medical Imaging, Toronto Western Hospital, Toronto (Canada)

    2007-12-15

    We studied four patients with diabetes mellitus and chronic renal failure who developed sudden choreic movement disorders. The clinical manifestations, laboratory findings, MR imaging findings, and clinical outcome in each patient were evaluated. All four patients had long-term diabetes mellitus and severe azotaemia. Brain MR findings consisted of bilateral symmetric basal ganglia lesions, with decreased signal intensity on T1-weighted images and increased signal intensity on T2-weighted images. All three patients who underwent diffusion-weighted MR imaging (DWI) showed signal intensities similar to those of the surroundings in regions corresponding to increased signal intensity on T2-weighted images, with slightly increased apparent diffusion coefficient (ADC) values. Two of the patients showed small focal areas of restricted diffusion within the basal ganglia lesions. After haemodialysis, follow-up MR imaging in all patients demonstrated that the basal ganglia lesions had regressed markedly, with some residual changes. The movement disorders also improved in all patients. A syndrome associated with acute bilateral basal ganglia lesions in diabetic uraemic patients is rare, with reversible changes demonstrated by clinical and imaging findings. DWI showed that the bilateral basal ganglia lesions in this syndrome were primarily vasogenic in origin, although there were small foci of cytotoxic oedema within the lesions. (orig.)

  2. Exploring the cognitive and motor functions of the basal ganglia: An integrative review of computational cognitive neuroscience models

    Directory of Open Access Journals (Sweden)

    Sebastien eHelie

    2013-12-01

    Full Text Available Many computational models of the basal ganglia have been proposed over the past twenty-five years. While computational neuroscience models have focused on closely matching the neurobiology of the basal ganglia, computational cognitive neuroscience models have focused on how the basal ganglia can be used to implement cognitive and motor functions. This review article focuses on computational cognitive neuroscience models of the basal ganglia and how they use the neuroanatomy of the basal ganglia to account for cognitive and motor functions such as categorization, instrumental conditioning, probabilistic learning, working memory, sequence learning, automaticity, reaching, handwriting, and eye saccades. A total of 19 basal ganglia models accounting for one or more of these functions are reviewed and compared. The review concludes with a discussion of the limitations of existing computational cognitive neuroscience models of the basal ganglia and prescriptions for future modeling, including the need for computational models of the basal ganglia that can simultaneously account for cognitive and motor functions, and the need for a more complete specification of the role of the basal ganglia in behavioral functions.

  3. MR-DTI and PET multimodal imaging of dopamine release within subdivisions of basal ganglia

    Science.gov (United States)

    Tziortzi, A.; Searle, G.; Tsoumpas, C.; Long, C.; Shotbolt, P.; Rabiner, E.; Jenkinson, M.; Gunn, R. N.

    2011-09-01

    The basal ganglia is a group of anatomical nuclei, functionally organised into limbic, associative and sensorimotor regions, which plays a central role in dopamine related neurological and psychiatric disorders. In this study, we combine two imaging modalities to enable the measurement of dopamine release in functionally related subdivisions of the basal ganglia. [11C]-(+)-PHNO Positron Emission Tomography (PET) measurements in the living human brain pre- and post-administration of amphetamine allow for the estimation of regional dopamine release. Combined Magnetic Resonance Diffusion Tensor Imaging (MR-DTI) data allows for the definition of functional territories of the basal ganglia from connectivity information. The results suggest that there is a difference in dopamine release among the connectivity derived functional subdivisions. Dopamine release is highest in the limbic area followed by the sensorimotor and then the associative area with this pattern reflected in both striatum and pallidum.

  4. Cognition and the basal ganglia: a possible substrate for procedural knowledge.

    Science.gov (United States)

    Phillips, A G; Carr, G D

    1987-08-01

    Disruption of neural activity within the basal ganglia of experimental animals causes selective learning deficits in tasks requiring switching between response strategies. These data along with reports of both general and specific intellectual impairment in patients with neurodegenerative disorders such as Parkinson's disease, appear to support the theory of cognitive functions of the basal ganglia. Recent studies have failed to confirm general cognitive or memory deficits in parkinsonian patients, but have identified deficiencies in devising and executing certain cognitive strategies. Following the lead of theorists such as Squire and Mishkin, this brief review emphasizes the distinction between procedural and declarative knowledge and examines the possible role of the basal ganglia in the acquisition and retention of procedural knowledge. PMID:3315145

  5. Single-photon-emission-computed-tomography (SPECT) in basal ganglia disorders

    International Nuclear Information System (INIS)

    In the past, SPECT investigations of regional cerebral blood flow have played a minor role in the diagnostic work-up of patients with basal ganglia disorders. More recently, however, interest in nuclear medicine procedures has dramatically increased since with the development of selective receptor ligands diagnostic tools have been provided which address the pathology in basal ganglia disorders more specifically than other diagnostic modalities. Evaluations of the pre- and postsynaptic aspects of the dopaminergic system, for example, deliver not only interesting data from the scientific point of view but also for the daily routine work. This paper summarizes some of the experience reported in the literature on SPECT investigations in basal ganglia disorders, such as Parkinson's disease, parkinsonian syndromes of other etiology, Wilson's and Huntington's disease, focal dystonias, and schizophrenia under treatment with neuroleptics. (orig.)

  6. Global dysrhythmia of cerebro-basal ganglia-cerebellar networks underlies motor tics following striatal disinhibition.

    Science.gov (United States)

    McCairn, Kevin W; Iriki, Atsushi; Isoda, Masaki

    2013-01-01

    Motor tics, a cardinal symptom of Tourette syndrome (TS), are hypothesized to arise from abnormalities within cerebro-basal ganglia circuits. Yet noninvasive neuroimaging of TS has previously identified robust activation in the cerebellum. To date, electrophysiological properties of cerebellar activation and its role in basal ganglia-mediated tic expression remain unknown. We performed multisite, multielectrode recordings of single-unit activity and local field potentials from the cerebellum, basal ganglia, and primary motor cortex using a pharmacologic monkey model of motor tics/TS. Following microinjections of bicuculline into the sensorimotor putamen, periodic tics occurred predominantly in the orofacial region, and a sizable number of cerebellar neurons showed phasic changes in activity associated with tic episodes. Specifically, 64% of the recorded cerebellar cortex neurons exhibited increases in activity, and 85% of the dentate nucleus neurons displayed excitatory, inhibitory, or multiphasic responses. Critically, abnormal discharges of cerebellar cortex neurons and excitatory-type dentate neurons mostly preceded behavioral tic onset, indicating their central origins. Latencies of pathological activity in the cerebellum and primary motor cortex substantially overlapped, suggesting that aberrant signals may be traveling along divergent pathways to these structures from the basal ganglia. Furthermore, the occurrence of tic movement was most closely associated with local field potential spikes in the cerebellum and primary motor cortex, implying that these structures may function as a gate to release overt tic movements. These findings indicate that tic-generating networks in basal ganglia mediated tic disorders extend beyond classical cerebro-basal ganglia circuits, leading to global network dysrhythmia including cerebellar circuits.

  7. The role of the basal ganglia in beat perception: neuroimaging and neuropsychological investigations.

    Science.gov (United States)

    Grahn, Jessica A

    2009-07-01

    Perception of musical rhythms is culturally universal. Despite this special status, relatively little is known about the neurobiology of rhythm perception, particularly with respect to beat processing. Findings are presented here from a series of studies that have specifically examined the neural basis of beat perception, using functional magnetic resonance imaging (fMRI) and studying patients with Parkinson's disease. fMRI data indicate that novel beat-based sequences robustly activate the basal ganglia when compared to irregular, nonbeat sequences. Furthermore, although most healthy participants find it much easier to discriminate changes in beat-based sequences compared to irregular sequences, Parkinson's disease patients fail to show the same degree of benefit. Taken together, these data suggest that the basal ganglia are performing a crucial function in beat processing. The results of an additional fMRI study indicate that the role of the basal ganglia is strongly linked to internal generation of the beat. Basal ganglia activity is greater when participants listen to rhythms in which internal generation of the beat is required, as opposed to rhythms with strongly externally cued beats. Functional connectivity between part of the basal ganglia (the putamen) and cortical motor areas (premotor and supplementary motor areas) is also higher during perception of beat rhythms compared to nonbeat rhythms. Increased connectivity between cortical motor and auditory areas is found in those with musical training. The findings from these converging methods strongly implicate the basal ganglia in processing a regular beat, particularly when internal generation of the beat is required. PMID:19673753

  8. Developmental Venous Anomaly With Asymmetrical Basal Ganglia Calcification: Two Case Reports and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Sarp

    2015-07-01

    Full Text Available Developmental venous anomaly (DVA is a common lesion formerly known as venous angioma. DVAs drain normal brain parenchyma; however, parenchymal abnormalities surrounding DVAs have been reported. Unilateral putamen and caudate calcification in the drainage territory of DVAs has so far been reported in 7 cases, all with deep venous drainage. We present two additional cases of DVAs, one with superficial and the other one with deep venous drainage, associated with basal ganglia calcifications. We emphasize that DVAs should be in the differential diagnosis of unilateral basal ganglia calcifications.

  9. Coupling in the cortico-basal ganglia circuit is aberrant in the ketamine model of schizophrenia.

    Science.gov (United States)

    Cordon, Ivan; Nicolás, María Jesús; Arrieta, Sandra; Lopetegui, Eneko; López-Azcárate, Jon; Alegre, Manuel; Artieda, Julio; Valencia, Miguel

    2015-08-01

    Recent studies have suggested the implication of the basal ganglia in the pathogenesis of schizophrenia. To investigate this hypothesis, here we have used the ketamine model of schizophrenia to determine the oscillatory abnormalities induced in the rat motor circuit of the basal ganglia. The activity of free moving rats was recorded in different structures of the cortico-basal ganglia circuit before and after an injection of a subanesthesic dose of ketamine (10mg/kg). Spectral estimates of the oscillatory activity, phase-amplitude cross-frequency coupling interactions (CFC) and imaginary event-related coherence together with animals׳ behavior were analyzed. Oscillatory patterns in the cortico-basal ganglia circuit were highly altered by the effect of ketamine. CFC between the phases of low-frequency activities (delta, 1-4; theta 4-8Hz) and the amplitude of high-gamma (~80Hz) and high-frequency oscillations (HFO) (~150Hz) increased dramatically and correlated with the movement increment shown by the animals. Between-structure analyses revealed that ketamine had also a massive effect in the low-frequency mediated synchronization of the HFO's across the whole circuit. Our findings suggest that ketamine administration results in an aberrant hypersynchronization of the whole cortico-basal circuit where the tandem theta/HFO seems to act as the main actor in the hyperlocomotion shown by the animals. Here we stress the importance of the basal ganglia circuitry in the ketamine model of schizophrenia and leave the door open to further investigations devoted to elucidate to what extent these abnormalities also reflect the prominent neurophysiological deficits observed in schizophrenic patients.

  10. How preparation changes the need for top-down control of the basal ganglia when inhibiting premature actions

    NARCIS (Netherlands)

    S. Jahfari; F. Verbruggen; M.J. Frank; L.J. Waldorp; L. Colzato; K.R. Ridderinkhof; B.U. Forstmann

    2012-01-01

    Goal-oriented signals from the prefrontal cortex gate the selection of appropriate actions in the basal ganglia. Key nodes within this fronto-basal ganglia action regulation network are increasingly engaged when one anticipates the need to inhibit and override planned actions. Here, we ask how the a

  11. Functions of the cortico-basal ganglia circuits for spoken language may extend beyond emotional-affective modulation in adults.

    Science.gov (United States)

    Hanakawa, Takashi; Hosoda, Chihiro

    2014-12-01

    We support Ackermann et al.'s proposal that the cortico-basal ganglia circuits may play essential roles in the evolution of spoken language. Here we discuss further evidence indicating that the cortico-basal ganglia circuits may contribute to various aspects of spoken language including planning, learning, and controlling of speech in adulthood.

  12. Conditional Routing of Information to the Cortex: A Model of the Basal Ganglia's Role in Cognitive Coordination

    Science.gov (United States)

    Stocco, Andrea; Lebiere, Christian; Anderson, John R.

    2010-01-01

    The basal ganglia play a central role in cognition and are involved in such general functions as action selection and reinforcement learning. Here, we present a model exploring the hypothesis that the basal ganglia implement a conditional information-routing system. The system directs the transmission of cortical signals between pairs of regions…

  13. Acute movement disorder with bilateral basal ganglia lesions in diabetic uremia

    Directory of Open Access Journals (Sweden)

    Gurusidheshwar M Wali

    2011-01-01

    Full Text Available Acute movement disorder associated with symmetrical basal ganglia lesions occurring in the background of diabetic end stage renal disease is a recently described condition. It has distinct clinico-radiological features and is commonly described in Asian patients. We report the first Indian case report of this potentially reversible condition and discuss its various clinico-radiological aspects.

  14. Bidirectional Plasticity in Striatonigral Synapses: A Switch to Balance Direct and Indirect Basal Ganglia Pathways

    Science.gov (United States)

    Aceves, Jose J.; Rueda-Orozco, Pavel E.; Hernandez-Martinez, Ricardo; Galarraga, Elvira; Bargas, Jose

    2011-01-01

    There is no hypothesis to explain how direct and indirect basal ganglia (BG) pathways interact to reach a balance during the learning of motor procedures. Both pathways converge in the substantia nigra pars reticulata (SNr) carrying the result of striatal processing. Unfortunately, the mechanisms that regulate synaptic plasticity in striatonigral…

  15. Hereditary haemochromatosis: a case of iron accumulation in the basal ganglia associated with a parkinsonian syndrome

    DEFF Research Database (Denmark)

    Nielsen, J.E.; Jensen, L.N.; Krabbe, K

    1995-01-01

    . A patient is reported with hereditary haemochromatosis and a syndrome of dementia, dysarthria, a slowly progressive gait disturbance, imbalance, muscle weakness, rigidity, bradykinesia, tremor, ataxia, and dyssynergia. The findings on MRI of a large signal decrease in the basal ganglia, consistent...

  16. Association Between Invisible Basal Ganglia and ZNF335 Mutations: A Case Report.

    Science.gov (United States)

    Sato, Rieko; Takanashi, Jun-Ichi; Tsuyusaki, Yu; Kato, Mitsuhiro; Saitsu, Hirotomo; Matsumoto, Naomichi; Takahashi, Takao

    2016-09-01

    ZNF335 was first reported in 2012 as a causative gene for microcephaly. Because only 1 consanguineous pedigree has ever been reported, the key clinical features associated with ZNF335 mutations remain unknown. In this article, we describe another family harboring ZNF335 mutations. The female proband was the first child of nonconsanguineous Japanese parents. At birth, microcephaly was absent; her head circumference was 32.0 cm (-0.6 SD). At 3 months, microcephaly was noted, (head circumference, 34.0 cm [-4.6 SD]). Brain MRI showed invisible basal ganglia, cerebral atrophy, brainstem hypoplasia, and cerebellar atrophy. At 33 months, (head circumference, 41.0 cm [-5.1 SD]), she had severe psychomotor retardation. After obtaining informed consent from her parents, we performed exome sequencing in the proband and identified 1 novel and 1 known mutation in ZNF335, namely, c.1399T>C (p.C467R) and c.1505A>G (p.Y502C), respectively. The mutations were individually transmitted by her parents, indicating that the proband was compound heterozygous for the mutations. Her brain imaging findings, including invisible basal ganglia, were similar to those observed in the previous case with ZNF335 mutations. We speculate that invisible basal ganglia may be the key feature of ZNF335 mutations. For infants presenting with both microcephaly and invisible basal ganglia, ZNF335 mutations should be considered as a differential diagnosis. PMID:27540107

  17. Neuroanatomical correlates of intelligence in healthy young adults: the role of basal ganglia volume.

    Directory of Open Access Journals (Sweden)

    Cosima Rhein

    Full Text Available BACKGROUND: In neuropsychiatric diseases with basal ganglia involvement, higher cognitive functions are often impaired. In this exploratory study, we examined healthy young adults to gain detailed insight into the relationship between basal ganglia volume and cognitive abilities under non-pathological conditions. METHODOLOGY/PRINCIPAL FINDINGS: We investigated 137 healthy adults that were between the ages of 21 and 35 years with similar educational backgrounds. Magnetic resonance imaging (MRI was performed, and volumes of basal ganglia nuclei in both hemispheres were calculated using FreeSurfer software. The cognitive assessment consisted of verbal, numeric and figural aspects of intelligence for either the fluid or the crystallised intelligence factor using the intelligence test Intelligenz-Struktur-Test (I-S-T 2000 R. Our data revealed significant correlations of the caudate nucleus and pallidum volumes with figural and numeric aspects of intelligence, but not with verbal intelligence. Interestingly, figural intelligence associations were dependent on sex and intelligence factor; in females, the pallidum volumes were correlated with crystallised figural intelligence (r = 0.372, p = 0.01, whereas in males, the caudate volumes were correlated with fluid figural intelligence (r = 0.507, p = 0.01. Numeric intelligence was correlated with right-lateralised caudate nucleus volumes for both females and males, but only for crystallised intelligence (r = 0.306, p = 0.04 and r = 0.459, p = 0.04, respectively. The associations were not mediated by prefrontal cortical subfield volumes when controlling with partial correlation analyses. CONCLUSIONS/SIGNIFICANCE: The findings of our exploratory analysis indicate that figural and numeric intelligence aspects, but not verbal aspects, are strongly associated with basal ganglia volumes. Unlike numeric intelligence, the type of figural intelligence appears to be related to distinct basal ganglia nuclei in a sex

  18. Evidence for a glutamatergic projection from the zona incerta to the basal ganglia of rats.

    Science.gov (United States)

    Heise, Claire E; Mitrofanis, John

    2004-01-19

    This study explores the organisation and neurochemical nature of the projections from the zona incerta (ZI) to the basal ganglia. Sprague-Dawley rats were anaesthetised with ketamine (100 mg/kg) and Rompun (10 mg/kg), and injections of cholera toxin subunit B were made into each of the following nuclei: the ZI, the substantia nigra (SN), the pedunculopontine tegmental nucleus (PpT), and the entopeduncular nucleus (Ep). Brains were aldehyde fixed, sectioned, and processed using standard methods. Tracer-labelled sections were then doubly labelled with antibodies to glutamate (Glu), nitric oxide synthase (NOS), parvalbumin (Pv), or glutamic acid decarboxylase (GAD; the latter two are markers for GABAergic cells); these neurochemicals characterise most types of ZI cells. After ZI injections, labelling was nonuniform across the different basal ganglia nuclei. The bulk of labelling, both anterograde and retrograde, was seen in the SN and PpT and, to a lesser extent, within the other nuclei of the basal ganglia (e.g., caudate-putamen, globus pallidus, subthalamus, Ep). In the SN, labelling was found in both major parts of the nucleus, the pars compacta and pars reticulata. Within the PpT, however, the bulk of labelling was limited to only one of the two sectors of the nucleus, namely, the pars dissipata (PpTd). The pars compacta of the PpT (PpTc) remained largely free of labelled profiles. After CTb injections into three basal ganglia nuclei (SN, PpT, Ep), most labelled cells in the ZI were glutamate+ and very few were NOS+ or gamma-aminobutyric acidergic. Overall, the results indicate that the ZI is in a position to influence preferentially the activity of the SN and PpTd of the basal ganglia via an excitatory, glutamatergic input. PMID:14689481

  19. Basal ganglia germinoma in children with associated ipsilateral cerebral and brain stem hemiatrophy

    Energy Technology Data Exchange (ETDEWEB)

    Ozelame, Rodrigo V.; Shroff, Manohar; Wood, Bradley; Bouffet, Eric; Bartels, Ute; Drake, James M.; Hawkins, Cynthia; Blaser, Susan [Hospital for Sick Children, Department of Diagnostic Imaging, Toronto, Ontario (Canada)

    2006-04-15

    Germinoma is the most common and least-malignant intracranial germ cell tumor, usually found in the midline. Germinoma that arises in the basal ganglia, called ectopic germinoma, is a rare and well-documented entity representing 5% to 10% of all intracranial germinomas. The association of cerebral and/or brain stem atrophy with basal ganglia germinoma on CT and MRI is found in 33% of the cases. To review the literature and describe the CT and MRI findings of basal ganglia germinoma in children, known as ectopic germinoma, with associated ipsilateral cerebral and brain stem hemiatrophy. Three brain CT and six brain MRI studies performed in four children at two institutions were retrospectively reviewed. All patients were male (case 1, 14 years; case 2, 13 years; case 3, 9 years; case 4, 13 years), with pathologically proved germinoma arising in the basal ganglia, and associated ipsilateral cerebral and/or brain stem hemiatrophy on the first imaging study. It is important to note that three of these children presented with cognitive decline, psychosis and slowly progressive hemiparesis as their indication for imaging. Imaging results on initial scans were varied. In all patients, the initial study showed ipsilateral cerebral and/or brain stem hemiatrophy, representing Wallerian degeneration. All patients who underwent CT imaging presented with a hyperdense or calcified lesion in the basal ganglia on unenhanced scans. Only one of these lesions had a mass effect on the surrounding structures. In one of these patients a large, complex, heterogeneous mass appeared 15 months later. Initial MR showed focal or diffusely increased T2 signal in two cases and heterogeneous signal in the other two. (orig.)

  20. Neuromodulatory Adaptive Combination of Correlation-based Learning in Cerebellum and Reward-based Learning in Basal Ganglia for Goal-directed Behavior Control

    Directory of Open Access Journals (Sweden)

    Sakyasingha eDasgupta

    2014-10-01

    Full Text Available Goal-directed decision making in biological systems is broadly based on associations between conditional and unconditional stimuli. This can be further classified as classical conditioning (correlation-based learning and operant conditioning (reward-based learning. A number of computational and experimental studies have well established the role of the basal ganglia in reward-based learning, where as the cerebellum plays an important role in developing specific conditioned responses. Although viewed as distinct learning systems, recent animal experiments point towards their complementary role in behavioral learning, and also show the existence of substantial two-way communication between these two brain structures. Based on this notion of co-operative learning, in this paper we hypothesize that the basal ganglia and cerebellar learning systems work in parallel and interact with each other. We envision that such an interaction is influenced by reward modulated heterosynaptic plasticity (RMHP rule at the thalamus, guiding the overall goal directed behavior. Using a recurrent neural network actor-critic model of the basal ganglia and a feed-forward correlation-based learning model of the cerebellum, we demonstrate that the RMHP rule can effectively balance the outcomes of the two learning systems. This is tested using simulated environments of increasing complexity with a four-wheeled robot in a foraging task in both static and dynamic configurations. Although modeled with a simplified level of biological abstraction, we clearly demonstrate that such a RMHP induced combinatorial learning mechanism, leads to stabler and faster learning of goal-directed behaviors, in comparison to the individual systems. Thus in this paper we provide a computational model for adaptive combination of the basal ganglia and cerebellum learning systems by way of neuromodulated plasticity for goal-directed decision making in biological and bio-mimetic organisms.

  1. Neuromodulatory adaptive combination of correlation-based learning in cerebellum and reward-based learning in basal ganglia for goal-directed behavior control.

    Science.gov (United States)

    Dasgupta, Sakyasingha; Wörgötter, Florentin; Manoonpong, Poramate

    2014-01-01

    Goal-directed decision making in biological systems is broadly based on associations between conditional and unconditional stimuli. This can be further classified as classical conditioning (correlation-based learning) and operant conditioning (reward-based learning). A number of computational and experimental studies have well established the role of the basal ganglia in reward-based learning, where as the cerebellum plays an important role in developing specific conditioned responses. Although viewed as distinct learning systems, recent animal experiments point toward their complementary role in behavioral learning, and also show the existence of substantial two-way communication between these two brain structures. Based on this notion of co-operative learning, in this paper we hypothesize that the basal ganglia and cerebellar learning systems work in parallel and interact with each other. We envision that such an interaction is influenced by reward modulated heterosynaptic plasticity (RMHP) rule at the thalamus, guiding the overall goal directed behavior. Using a recurrent neural network actor-critic model of the basal ganglia and a feed-forward correlation-based learning model of the cerebellum, we demonstrate that the RMHP rule can effectively balance the outcomes of the two learning systems. This is tested using simulated environments of increasing complexity with a four-wheeled robot in a foraging task in both static and dynamic configurations. Although modeled with a simplified level of biological abstraction, we clearly demonstrate that such a RMHP induced combinatorial learning mechanism, leads to stabler and faster learning of goal-directed behaviors, in comparison to the individual systems. Thus, in this paper we provide a computational model for adaptive combination of the basal ganglia and cerebellum learning systems by way of neuromodulated plasticity for goal-directed decision making in biological and bio-mimetic organisms. PMID:25389391

  2. Acute Chorea Characterized by Bilateral Basal Ganglia Lesions in a Patient with Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    İbrahim DOĞAN

    2015-09-01

    Full Text Available The syndrome of acute bilateral basal ganglia lesions associated with uremia presents with parkinsonism, altered mental status, and chorea in association with specific imaging findings in the basal ganglia. It is an uncommon syndrome seen generally in patients with diabetes mellitus and renal failure. We report a male patient with diabetes mellitus who received hemodialysis treatment 3 days a week for 5 years and suffered from choreic movements developed suddenly and associated with bilateral basal ganglia lesions. In the brain magnetic resonance (MR imaging, isointense was detected in sequence T1 in the bilateral basal ganglions and hyperintense lesion was determined in T2 and FLAIR sequences. The patient was administered daily hemodialysis and neuroleptic treatment. After intensified hemodialysis, his symptoms and follow-up brain MR imaging showed marked improvement. The underlying mechanism of such lesions may be associated with metabolic, as well as vascular factors. Acute choreic movements may be seen in patients with diabetic nephropathy and intensification of hemodialysis treatment along with blood glucose regulation may provide improvement in this syndrome.

  3. Using a hybrid neuron in physiologically inspired models of the basal ganglia

    Directory of Open Access Journals (Sweden)

    Corey Michael Thibeault

    2013-07-01

    Full Text Available Our current understanding of the basal ganglia has facilitated the creation of computational models that have contributed novel theories, explored new functional anatomy and demonstrated results complementing physiological experiments. However, the utility of these models extends beyond these applications. Particularly in neuromorphic engineering, where the basal ganglia's role in computation is important for applications such as power efficient autonomous agents and model-based control strategies. The neurons used in existing computational models of the basal ganglia however, are not amenable for many low-power hardware implementations. Motivated by a need for more hardware accessible networks, we replicate four published models of the basal ganglia, spanning single neuron and small networks, replacing the more computationally expensive neuron models with an Izhikevich hybrid neuron. This begins with a network modeling action-selection, where the basal activity levels and the ability to appropriately select the most salient input is reproduced. A Parkinson's disease model is then explored under normal conditions, Parkinsonian conditions and during subthalamic nucleus deep brain stimulation. The resulting network is capable of replicating the loss of thalamic relay capabilities in the Parkinsonian state and its return under deep brain stimulation. This is also demonstrated using a network capable of action-selection. Finally, a study of correlation transfer under different patterns of Parkinsonian activity is presented. These networks successfully captured the significant results of the originals studies. This not only creates a foundation for neuromorphic hardware implementations but may also support the development of large-scale biophysical models. The former potentially providing a way of improving the efficacy of deep brain stimulation and the latter allowing for the efficient simulation of larger more comprehensive networks.

  4. Surprise disrupts cognition via a fronto-basal ganglia suppressive mechanism.

    Science.gov (United States)

    Wessel, Jan R; Jenkinson, Ned; Brittain, John-Stuart; Voets, Sarah H E M; Aziz, Tipu Z; Aron, Adam R

    2016-04-18

    Surprising events markedly affect behaviour and cognition, yet the underlying mechanism is unclear. Surprise recruits a brain mechanism that globally suppresses motor activity, ostensibly via the subthalamic nucleus (STN) of the basal ganglia. Here, we tested whether this suppressive mechanism extends beyond skeletomotor suppression and also affects cognition (here, verbal working memory, WM). We recorded scalp-EEG (electrophysiology) in healthy participants and STN local field potentials in Parkinson's patients during a task in which surprise disrupted WM. For scalp-EEG, surprising events engage the same independent neural signal component that indexes action stopping in a stop-signal task. Importantly, the degree of this recruitment mediates surprise-related WM decrements. Intracranially, STN activity is also increased post surprise, especially when WM is interrupted. These results suggest that surprise interrupts cognition via the same fronto-basal ganglia mechanism that interrupts action. This motivates a new neural theory of how cognition is interrupted, and how distraction arises after surprising events.

  5. Computational models of basal-ganglia pathway functions: Focus on functional neuroanatomy

    Directory of Open Access Journals (Sweden)

    Henning eSchroll

    2013-12-01

    Full Text Available Over the past 15 years, computational models have had a considerable impact on basal-ganglia research. Most of these models implement multiple distinct basal ganglia pathways and assume them to fulfill different functions. As there is now a multitude of different models, it has become complex to keep track of their various, sometimes just marginally different assumptions on pathway functions. Moreover, it has become a challenge to oversee to what extent individual assumptions are corroborated or challenged by empirical data. Focusing on computational, but also considering non-computational models, we review influential concepts of pathway functions and show to what extent they are compatible with or contradict each other. Moreover, we outline how empirical evidence favors or challenges specific assumptions and propose experiments that allow testing assumptions against each other.

  6. Extrahepatic portal vein obstruction with parkinsonism and symmetric hyperintense basal ganglia on T1 weighted MRI

    Directory of Open Access Journals (Sweden)

    Jayalakshmi Sita

    2006-01-01

    Full Text Available Abnormal high signal in the globus pallidus on T1 weighted magnetic resonance imaging (MRI of the brain has been well described in patients with chronic liver disease. It may be related to liver dysfunction or portal-systemic shunting. We report a case of extra hepatic portal vein obstruction with portal hypertension and esophageal varices that presented with extra pyramidal features. T1 weighted MRI brain scans showed increased symmetrical signal intensities in the basal ganglia. Normal hepatic function in this patient emphasizes the role of portal- systemic communications in the development of these hyperintensities, which may be due to deposition of paramagnetic substances like manganese in the basal ganglia.

  7. Acute Psychosis Associated with Subcortical Stroke: Comparison between Basal Ganglia and Mid-Brain Lesions

    Directory of Open Access Journals (Sweden)

    Aaron McMurtray

    2014-01-01

    Full Text Available Acute onset of psychosis in an older or elderly individual without history of previous psychiatric disorders should prompt a thorough workup for neurologic causes of psychiatric symptoms. This report compares and contrasts clinical features of new onset of psychotic symptoms between two patients, one with an acute basal ganglia hemorrhagic stroke and another with an acute mid-brain ischemic stroke. Delusions and hallucinations due to basal ganglia lesions are theorized to develop as a result of frontal lobe dysfunction causing impairment of reality checking pathways in the brain, while visual hallucinations due to mid-brain lesions are theorized to develop due to dysregulation of inhibitory control of the ponto-geniculate-occipital system. Psychotic symptoms occurring due to stroke demonstrate varied clinical characteristics that depend on the location of the stroke within the brain. Treatment with antipsychotic medications may provide symptomatic relief.

  8. Role of basal ganglia in sleep-wake regulation: neural circuitry and clinical significance

    Directory of Open Access Journals (Sweden)

    Ramalingam Vetrivelan

    2010-11-01

    Full Text Available Researchers over the last decade have made substantial progress towards understanding the roles of dopamine and the basal ganglia in the control of sleep-wake behavior. In this review, we outline recent advancements regarding dopaminergic modulation of sleep through the basal ganglia (BG and extra-BG sites. Our main hypothesis is that dopamine promotes sleep by its action on the D2 receptors in the BG and promotes wakefulness by its action on D1 and D2 receptors in the extra-BG sites. This hypothesis implicates dopamine depletion in the BG (such as in Parkinson’s disease in causing frequent nighttime arousal and overall insomnia. Furthermore, the arousal effects of psychostimulants (methamphetamine, cocaine and modafinil may be linked to the ventral periaquductal grey (vPAG dopaminergic circuitry targeting the extra-BG sleep-wake network.

  9. Striatal Cholinergic Interneurons Control Motor Behavior and Basal Ganglia Function in Experimental Parkinsonism.

    Science.gov (United States)

    Maurice, Nicolas; Liberge, Martine; Jaouen, Florence; Ztaou, Samira; Hanini, Marwa; Camon, Jeremy; Deisseroth, Karl; Amalric, Marianne; Kerkerian-Le Goff, Lydia; Beurrier, Corinne

    2015-10-27

    Despite evidence showing that anticholinergic drugs are of clinical relevance in Parkinson's disease (PD), the causal role of striatal cholinergic interneurons (CINs) in PD pathophysiology remains elusive. Here, we show that optogenetic inhibition of CINs alleviates motor deficits in PD mouse models, providing direct demonstration for their implication in parkinsonian motor dysfunctions. As neural correlates, CIN inhibition in parkinsonian mice differentially impacts the excitability of striatal D1 and D2 medium spiny neurons, normalizes pathological bursting activity in the main basal ganglia output structure, and increases the functional weight of the direct striatonigral pathway in cortical information processing. By contrast, CIN inhibition in non-lesioned mice does not affect locomotor activity, equally modulates medium spiny neuron excitability, and does not modify spontaneous or cortically driven activity in the basal ganglia output, suggesting that the role of these interneurons in motor function is highly dependent on dopamine tone. PMID:26489458

  10. Striatal Cholinergic Interneurons Control Motor Behavior and Basal Ganglia Function in Experimental Parkinsonism

    Directory of Open Access Journals (Sweden)

    Nicolas Maurice

    2015-10-01

    Full Text Available Despite evidence showing that anticholinergic drugs are of clinical relevance in Parkinson’s disease (PD, the causal role of striatal cholinergic interneurons (CINs in PD pathophysiology remains elusive. Here, we show that optogenetic inhibition of CINs alleviates motor deficits in PD mouse models, providing direct demonstration for their implication in parkinsonian motor dysfunctions. As neural correlates, CIN inhibition in parkinsonian mice differentially impacts the excitability of striatal D1 and D2 medium spiny neurons, normalizes pathological bursting activity in the main basal ganglia output structure, and increases the functional weight of the direct striatonigral pathway in cortical information processing. By contrast, CIN inhibition in non-lesioned mice does not affect locomotor activity, equally modulates medium spiny neuron excitability, and does not modify spontaneous or cortically driven activity in the basal ganglia output, suggesting that the role of these interneurons in motor function is highly dependent on dopamine tone.

  11. Two Case Reports on Thalamic and Basal Ganglia Involvement in Children with Dengue Fever

    Science.gov (United States)

    Adhikari, Lihini; Wijesekera, Saraji; Wijayawardena, Maheshaka; Chandrasiri, Suchithra

    2016-01-01

    There have been increasing numbers of case reports of dengue infection with unusual manifestations. Such unusual manifestations including acute liver failure and encephalopathy could be manifested even in the absence of significant plasma leakage. Further, severe organ involvement including nervous system involvement indicates severe dengue infection. However, neurological manifestations of dengue fever are rare. This is the first case report of dengue infection with thalamic and basal ganglia involvement in Sri Lanka.

  12. Two Case Reports on Thalamic and Basal Ganglia Involvement in Children with Dengue Fever

    Science.gov (United States)

    Adhikari, Lihini; Wijesekera, Saraji; Wijayawardena, Maheshaka; Chandrasiri, Suchithra

    2016-01-01

    There have been increasing numbers of case reports of dengue infection with unusual manifestations. Such unusual manifestations including acute liver failure and encephalopathy could be manifested even in the absence of significant plasma leakage. Further, severe organ involvement including nervous system involvement indicates severe dengue infection. However, neurological manifestations of dengue fever are rare. This is the first case report of dengue infection with thalamic and basal ganglia involvement in Sri Lanka. PMID:27478661

  13. FROM REINFORCEMENT LEARNING MODELS OF THE BASAL GANGLIA TO THE PATHOPHYSIOLOGY OF PSYCHIATRIC AND NEUROLOGICAL DISORDERS

    OpenAIRE

    Maia, Tiago V.; Frank, Michael J.

    2011-01-01

    Over the last decade and a half, reinforcement learning models have fostered an increasingly sophisticated understanding of the functions of dopamine and cortico-basal ganglia-thalamo-cortical (CBGTC) circuits. More recently, these models, and the insights that they afford, have started to be used to understand key aspects of several psychiatric and neurological disorders that involve disturbances of the dopaminergic system and CBGTC circuits. We review this approach and its existing and pote...

  14. Dopamine transporter density of the basal ganglia assessed with I-123 IPT SPECT in methamphetamine abusers

    International Nuclear Information System (INIS)

    Functional imaging of dopamine transporter (DAT) defines integrity of the dopaminergic system, and DAT is the target site of drugs of abuse such as cocaine and methamphetamine. Functional imaging the DAT may be a sensitive and selective indicator of neurotoxic change by the drug. The aim of the present study is to evaluate the clinical implications of qualitative/quantitative analyses of dopamine transporter imaging in methamphetamine abusers. Six detoxified methamphetamine abusers (abuser group) and 4 volunteers (control group) were enrolled in this study. Brain MRI was performed in all of abuser group. Abuser group underwent psychiatric and depression assessment using brief psychiatric rating scale (BPRS) and Hamilton depression rating scale (HAMD), respectively. All of the subjects underwent I-123 IPT SPECT (IPT SPECT). IPT SPECT image was analysed with visual qualitative method and quantitative method using basal ganglia dopamine transporter (DAT) specific/non-specific binding ratio (SBR). Comparison of DAT SBR between abuser and control groups was performed. We also performed correlation tests between psychiatric and depression assessment results and DAT SBR in abuser group. All of abuser group showed normal MRI finding, but had residual psychiatric and depressive symptoms, and psychiatric and depressive symptom scores were exactly correlated (r=1.0, ρ =0.005) each other. Five of them showed abnormal finding on qualitative visual I-123 IPT SPECT. Abuser group had lower basal ganglia DAT SBR than that of control (2.38 ± 0.20 vs 3.04 ± 0.27, ρ =0.000). Psychiatric and depressive symptoms were negatively well correlated with basal ganglia DAT SBR (r=-0.908, ρ =0.012, r=-0.924, ρ =0.009) This results suggest that dopamine transporter imaging using I-123 IPT SPECT may be used to evaluate dopaminergic system of the basal ganglia and the clinical status in methamphetamine abusers

  15. Secondary attention deficit/hyperactivity disorder due to right basal ganglia injury: A case report

    OpenAIRE

    Ceylan, Mehmet Fatih; AKCA, Ömer Faruk

    2013-01-01

    Attention deficit/hyperactivity disorder (ADHD) is a frequent and commonly studied neuropsychiatric disorder in children and adolescents. The symptoms of ADHD include inattention and/or hyperactivity and impulsivity. Diagnosis of ADHD requires a persistent pattern of symptoms beginning before the age of 7 except for secondary ADHD. Secondary ADHD may occur as a consequence of childhood traumatic brain injury. A patient with secondary ADHD as a result of right basal ganglia injury is presented...

  16. Dopamine transporter density of the basal ganglia assessed with I-123 IPT SPECT in methamphetamine abusers

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Joo Ryung; Ahn, Byeong Cheol [Kyungpook National University Medical School, Daegu (Korea, Republic of); Kewm, Do Hun [National Bugok Mental Hospital, Changryung (Korea, Republic of)] (and others)

    2005-10-15

    Functional imaging of dopamine transporter (DAT) defines integrity of the dopaminergic system, and DAT is the target site of drugs of abuse such as cocaine and methamphetamine. Functional imaging the DAT may be a sensitive and selective indicator of neurotoxic change by the drug. The aim of the present study is to evaluate the clinical implications of qualitative/quantitative analyses of dopamine transporter imaging in methamphetamine abusers. Six detoxified methamphetamine abusers (abuser group) and 4 volunteers (control group) were enrolled in this study. Brain MRI was performed in all of abuser group. Abuser group underwent psychiatric and depression assessment using brief psychiatric rating scale (BPRS) and Hamilton depression rating scale (HAMD), respectively. All of the subjects underwent I-123 IPT SPECT (IPT SPECT). IPT SPECT image was analysed with visual qualitative method and quantitative method using basal ganglia dopamine transporter (DAT) specific/non-specific binding ratio (SBR). Comparison of DAT SBR between abuser and control groups was performed. We also performed correlation tests between psychiatric and depression assessment results and DAT SBR in abuser group. All of abuser group showed normal MRI finding, but had residual psychiatric and depressive symptoms, and psychiatric and depressive symptom scores were exactly correlated (r=1.0, {rho} =0.005) each other. Five of them showed abnormal finding on qualitative visual I-123 IPT SPECT. Abuser group had lower basal ganglia DAT SBR than that of control (2.38 {+-} 0.20 vs 3.04 {+-} 0.27, {rho} =0.000). Psychiatric and depressive symptoms were negatively well correlated with basal ganglia DAT SBR (r=-0.908, {rho} =0.012, r=-0.924, {rho} =0.009) This results suggest that dopamine transporter imaging using I-123 IPT SPECT may be used to evaluate dopaminergic system of the basal ganglia and the clinical status in methamphetamine abusers.

  17. Actor-critic models of reinforcement learning in the basal ganglia: From natural to artificial rats

    OpenAIRE

    Khamassi, Mehdi; Lachèze, Loïc; Girard, Benoît; Berthoz, Alain; Guillot, Agnès

    2005-01-01

    International audience Since 1995, numerous Actor–Critic architectures for reinforcement learning have been proposed as models of dopamine-like reinforcement learning mechanisms in the rat's basal ganglia. However, these models were usually tested in different tasks, and it is then difficult to compare their efficiency for an autonomous animat. We present here the comparison of four architectures in an animat as it per forms the same reward-seeking task. This will illustrate the consequenc...

  18. Neural circuits and topographic organization of the basal ganglia and related regions.

    Science.gov (United States)

    Nakano, K

    2000-09-01

    The present review was attempted to analyze the multiple channels of basal ganglia-thalamocortical connections, and the connections of their related nuclei. The prefrontal and motor areas consist of a number of modules, which seem to provide multiple subloops of the basal ganglia-thalamocortical connections in subhuman primates. There may be a great degree of convergence of the limbic, associative and motor loops at the level of the striatum, substantia nigra, pallidum, and the subthalamic nucleus as well as the pedunculopontine nucleus. Nigral dopaminergic neurons receive limbic input directly as well as indirectly through the striosomes in the striatum. Dopamine contributes to behavioral learning by signaling motivation and reinforcement. The pedunculopontine nucleus might be involved in behavioral state control, learning and reinforcement processes, locomotion and autonomic functions. Each subdivision of the motor areas receives a mixed and weighted transthalamic input from both the cerebellum and basal ganglia. In particular, based on the author's data, the hand/arm motor area and adjacent premotor area receive strong superficial basal ganglia-thalamocortical projections as well as the deep cerebello-thalamocortical projections. These areas, have very dense corticocotrical connections with other cortical areas, receive polymodal afferents from the parietal and temporal cortices, and integrated information, via multiple routes, from the prefrontal cortex. The author suggests that the ventrolateral part of the caudal medial pallidal segment (GPi) and the ventromedial part of the GPi are linked directly to these areas by ways of the oral part of ventral lateral nucleus (VLo) and the ventral part of the parvicellular part of ventral anterior nucleus (VApc), respectively. These connections are thought to be involved in the acquisition and coordination of motor sequences. PMID:10984656

  19. The role of the basal ganglia in learning and memory: Insight from Parkinson's disease

    OpenAIRE

    Foerde, Karin; Shohamy, Daphna

    2011-01-01

    It has long been known that memory is not a single process. Rather, there are different kinds of memory that are supported by distinct neural systems. This idea stemmed from early findings of dissociable patterns of memory impairments in patients with selective damage to different brain regions. These studies highlighted the role of the basal ganglia in non-declarative memory, such as procedural or habit learning, contrasting it with the known role of the medial temporal lobes in declarative ...

  20. Role of movement in long-term basal ganglia changes: implications for abnormal motor responses

    OpenAIRE

    Nicola eSimola; Micaela eMorelli; Giuseppe eFrazzitta; Lucia eFrau

    2013-01-01

    Abnormal involuntary movements and dyskinesias elicited by drugs that stimulate dopamine receptors in the basal ganglia are a major issue in the management of Parkinson’s disease (PD). Preclinical studies in dopamine-denervated animals have contributed to the modeling of these abnormal movements, but the precise neurochemical and functional mechanisms underlying these untoward effects are still elusive. It has recently been suggested that the performance of movement may itself promote the lat...

  1. Role of movement in long-term basal ganglia changes: implications for abnormal motor responses

    OpenAIRE

    Simola, Nicola; Morelli, Micaela; Frazzitta, Giuseppe; Frau, Lucia

    2013-01-01

    Abnormal involuntary movements (AIMs) and dyskinesias elicited by drugs that stimulate dopamine receptors in the basal ganglia are a major issue in the management of Parkinson’s disease (PD). Preclinical studies in dopamine-denervated animals have contributed to the modeling of these abnormal movements, but the precise neurochemical and functional mechanisms underlying these untoward effects are still elusive. It has recently been suggested that the performance of movement may itself promote ...

  2. Functional properties of the basal ganglia's re-entrant loop architecture: selection and reinforcement.

    Science.gov (United States)

    Redgrave, P; Vautrelle, N; Reynolds, J N J

    2011-12-15

    Multifunctional agents with limited motor resources must decide what actions will best ensure their survival. Moreover, given that in an unpredictable world things don't always work out, considerable advantage is to be gained by learning from experience - instrumental behaviour that maximises reward and minimises punishment. In this review we will argue that the re-entrant looped architecture of the basal ganglia represents biological solutions to these fundamental behavioural problems of selection and reinforcement. A potential solution to the selection problem is provided for by selective disinhibition within the parallel loop architecture that connects the basal ganglia with external neural structures. The relay points within these loops permit the signals of a particular channel to be modified by external influences. In part, these influences have the capacity to modify overall selections so that the probability of re-selecting reinforced behaviours in the future is altered. This is the basic process of instrumental learning, which we suggest decomposes into two sub-problems for the agent: (i) learning which external events it causes to happen and learning precisely what it is doing that is causal; and (ii) having determined agency and discovered novel action-outcome routines, how best to exploit this knowledge to maximise future reward acquisitions. Considerations of connectional architecture and signal timing suggest that the short-latency, sensory-evoked dopamine response, which can modulate the re-entrant loop structure within the basal ganglia, is ideally suited to reinforce the determination of agency and the discovery of novel actions. Alternatively, recent studies showing that presence or absence of reward can selectively modulate the magnitude of signals in structures providing input signals to the basal ganglia, offer an alternative mechanism for biasing selection within the re-entrant loop architecture. We suggest that this mechanism may be better

  3. Two Case Reports on Thalamic and Basal Ganglia Involvement in Children with Dengue Fever.

    Science.gov (United States)

    Liyanage, Guwani; Adhikari, Lihini; Wijesekera, Saraji; Wijayawardena, Maheshaka; Chandrasiri, Suchithra

    2016-01-01

    There have been increasing numbers of case reports of dengue infection with unusual manifestations. Such unusual manifestations including acute liver failure and encephalopathy could be manifested even in the absence of significant plasma leakage. Further, severe organ involvement including nervous system involvement indicates severe dengue infection. However, neurological manifestations of dengue fever are rare. This is the first case report of dengue infection with thalamic and basal ganglia involvement in Sri Lanka. PMID:27478661

  4. Bilateral basal ganglia lesions in patients with end-stage diabetic nephropathy.

    Science.gov (United States)

    Li, Jordan Y Z; Yong, Tuck Y; Sebben, Ruben; Khoo, Eewin; Disney, Alex P S

    2008-02-01

    Acute movement disorder associated with reversible bilateral basal ganglia lesions is an increasingly recognized syndrome in patients with end-stage renal disease, especially in the setting of concurrent diabetes mellitus. We report an elderly man with end-stage diabetic nephropathy treated by daily automated peritoneal dialysis who developed subacute symptoms of gait disturbance, dysarthria, dysphagia and lethargy. Computed tomography and magnetic resonance imaging of the head revealed bilateral symmetrical basal ganglia lesions. Repeat imaging 3 weeks later showed that these lesions had regressed spontaneously. However, his neurological symptoms improved slowly. These findings were similar to 23 other cases in the literature. Review of these cases shows that clinical features were predominantly bradykinesia, gait disturbance and concurrent metabolic acidosis (observed in 90% of cases). The pathogenesis of this condition has not been clearly defined, but uraemia may be an aggravating factor in predisposed patients, particularly in the presence of diabetic microvascular disease. There is no specific treatment for this condition; supportive measures are the mainstay of management. In the majority of patients, neurological improvement lags behind regression of basal ganglia lesions seen with neuroimaging, and the long-term outcome is variable.

  5. Early imaging findings in germ cell tumors arising from the basal ganglia

    Energy Technology Data Exchange (ETDEWEB)

    Lee, So Mi [Seoul National University College of Medicine, Department of Radiology, 101 Daehak-ro, Jongno-gu, Seoul (Korea, Republic of); Kyungpook National University Medical Center, Department of Radiology, Daegu (Korea, Republic of); Kim, In-One; Choi, Young Hun; Cheon, Jung-Eun; Kim, Woo Sun [Seoul National University College of Medicine, Department of Radiology and Institute of Radiation Medicine, 101 Daehak-ro, Jongno-gu, Seoul (Korea, Republic of); Cho, Hyun-Hae [Seoul National University College of Medicine, Department of Radiology, 101 Daehak-ro, Jongno-gu, Seoul (Korea, Republic of); Ewha Woman' s University Mokdong Hospital, Department of Radiology, Seoul (Korea, Republic of); You, Sun Kyoung [Seoul National University College of Medicine, Department of Radiology, 101 Daehak-ro, Jongno-gu, Seoul (Korea, Republic of); Chungnam National University Hospital, Department of Radiology, Daejeon (Korea, Republic of)

    2016-05-15

    It is difficult to diagnosis early stage germ cell tumors originating in the basal ganglia, but early recognition is important for better outcome. To evaluate serial MR images of basal ganglia germ cell tumors, with emphasis on the features of early stage tumors. We retrospectively reviewed serial MR images of 15 tumors in 14 children and young adults. We categorized MR images of the tumors as follows: type I, ill-defined patchy lesions (<3 cm) without cyst; type II, small mass lesions (<3 cm) with cyst; and type III, large lesions (≥3 cm) with cyst. We also assessed temporal changes of the MR images. On the initial images, 8 of 11 (73%) type I tumors progressed to types II or III, and 3 of 4 (75%) type II tumors progressed to type III. The remaining 4 tumors did not change in type. All type II tumors (5/5, 100%) that changed from type I had a few tiny cysts. Intratumoral hemorrhage was observed even in the type I tumor. Ipsilateral hemiatrophy was observed in most of the tumors (13/15, 87%) on initial MR images. As tumors grew, cystic changes, intratumoral hemorrhage, and ipsilateral hemiatrophy became more apparent. Early stage basal ganglia germ cell tumors appear as ill-defined small patchy hyperintense lesions without cysts on T2-weighted images, are frequently associated with ipsilateral hemiatrophy, and sometimes show microhemorrhage. Tumors develop tiny cysts at a relatively early stage. (orig.)

  6. Early imaging findings in germ cell tumors arising from the basal ganglia

    International Nuclear Information System (INIS)

    It is difficult to diagnosis early stage germ cell tumors originating in the basal ganglia, but early recognition is important for better outcome. To evaluate serial MR images of basal ganglia germ cell tumors, with emphasis on the features of early stage tumors. We retrospectively reviewed serial MR images of 15 tumors in 14 children and young adults. We categorized MR images of the tumors as follows: type I, ill-defined patchy lesions (<3 cm) without cyst; type II, small mass lesions (<3 cm) with cyst; and type III, large lesions (≥3 cm) with cyst. We also assessed temporal changes of the MR images. On the initial images, 8 of 11 (73%) type I tumors progressed to types II or III, and 3 of 4 (75%) type II tumors progressed to type III. The remaining 4 tumors did not change in type. All type II tumors (5/5, 100%) that changed from type I had a few tiny cysts. Intratumoral hemorrhage was observed even in the type I tumor. Ipsilateral hemiatrophy was observed in most of the tumors (13/15, 87%) on initial MR images. As tumors grew, cystic changes, intratumoral hemorrhage, and ipsilateral hemiatrophy became more apparent. Early stage basal ganglia germ cell tumors appear as ill-defined small patchy hyperintense lesions without cysts on T2-weighted images, are frequently associated with ipsilateral hemiatrophy, and sometimes show microhemorrhage. Tumors develop tiny cysts at a relatively early stage. (orig.)

  7. Integration of reinforcement learning and optimal decision-making theories of the basal ganglia.

    Science.gov (United States)

    Bogacz, Rafal; Larsen, Tobias

    2011-04-01

    This article seeks to integrate two sets of theories describing action selection in the basal ganglia: reinforcement learning theories describing learning which actions to select to maximize reward and decision-making theories proposing that the basal ganglia selects actions on the basis of sensory evidence accumulated in the cortex. In particular, we present a model that integrates the actor-critic model of reinforcement learning and a model assuming that the cortico-basal-ganglia circuit implements a statistically optimal decision-making procedure. The values of cortico-striatal weights required for optimal decision making in our model differ from those provided by standard reinforcement learning models. Nevertheless, we show that an actor-critic model converges to the weights required for optimal decision making when biologically realistic limits on synaptic weights are introduced. We also describe the model's predictions concerning reaction times and neural responses during learning, and we discuss directions required for further integration of reinforcement learning and optimal decision-making theories. PMID:21222528

  8. The role of the basal ganglia in learning and memory: insight from Parkinson's disease.

    Science.gov (United States)

    Foerde, Karin; Shohamy, Daphna

    2011-11-01

    It has long been known that memory is not a single process. Rather, there are different kinds of memory that are supported by distinct neural systems. This idea stemmed from early findings of dissociable patterns of memory impairments in patients with selective damage to different brain regions. These studies highlighted the role of the basal ganglia in non-declarative memory, such as procedural or habit learning, contrasting it with the known role of the medial temporal lobes in declarative memory. In recent years, major advances across multiple areas of neuroscience have revealed an important role for the basal ganglia in motivation and decision making. These findings have led to new discoveries about the role of the basal ganglia in learning and highlighted the essential role of dopamine in specific forms of learning. Here we review these recent advances with an emphasis on novel discoveries from studies of learning in patients with Parkinson's disease. We discuss how these findings promote the development of current theories away from accounts that emphasize the verbalizability of the contents of memory and towards a focus on the specific computations carried out by distinct brain regions. Finally, we discuss new challenges that arise in the face of accumulating evidence for dynamic and interconnected memory systems that jointly contribute to learning. PMID:21945835

  9. Supplementary motor area and presupplementary motor area: targets of basal ganglia and cerebellar output.

    Science.gov (United States)

    Akkal, Dalila; Dum, Richard P; Strick, Peter L

    2007-10-01

    We used retrograde transneuronal transport of neurotropic viruses in Cebus monkeys to examine the organization of basal ganglia and cerebellar projections to two cortical areas on the medial wall of the hemisphere, the supplementary motor area (SMA) and the pre-SMA. We found that both of these cortical areas are the targets of disynaptic projections from the dentate nucleus of the cerebellum and from the internal segment of the globus pallidus (GPi). On average, the number of pallidal neurons that project to the SMA and pre-SMA is approximately three to four times greater than the number of dentate neurons that project to these cortical areas. GPi neurons that project to the pre-SMA are located in a rostral, "associative" territory of the nucleus, whereas GPi neurons that project to the SMA are located in a more caudal and ventral "sensorimotor" territory. Similarly, dentate neurons that project to the pre-SMA are located in a ventral, "nonmotor" domain of the nucleus, whereas dentate neurons that project to the SMA are located in a more dorsal, "motor" domain. The differential origin of subcortical projections to the SMA and pre-SMA suggests that these cortical areas are nodes in distinct neural systems. Although both systems are the target of outputs from the basal ganglia and the cerebellum, these two cortical areas seem to be dominated by basal ganglia input. PMID:17913900

  10. Integration of reinforcement learning and optimal decision-making theories of the basal ganglia.

    Science.gov (United States)

    Bogacz, Rafal; Larsen, Tobias

    2011-04-01

    This article seeks to integrate two sets of theories describing action selection in the basal ganglia: reinforcement learning theories describing learning which actions to select to maximize reward and decision-making theories proposing that the basal ganglia selects actions on the basis of sensory evidence accumulated in the cortex. In particular, we present a model that integrates the actor-critic model of reinforcement learning and a model assuming that the cortico-basal-ganglia circuit implements a statistically optimal decision-making procedure. The values of cortico-striatal weights required for optimal decision making in our model differ from those provided by standard reinforcement learning models. Nevertheless, we show that an actor-critic model converges to the weights required for optimal decision making when biologically realistic limits on synaptic weights are introduced. We also describe the model's predictions concerning reaction times and neural responses during learning, and we discuss directions required for further integration of reinforcement learning and optimal decision-making theories.

  11. Serial dynamic CT scan in patients with acute basal ganglia infarctions

    International Nuclear Information System (INIS)

    Dynamic computed tomography (CT) was performed on 15 patients (37 to 93 years of age) with acute basal ganglia infarctions, and the perfusion patterns of the infarcted regions on CT were evaluated. The initial dynamic CT was performed within 12 hours after onset, while the serial studies of the dynamic CT were performed on the 3rd and 7th days. The left-over-right ratio in the peak value in the basal ganglia in 15 normal subjects was 1.01 ± 0.03 (mean ± SD), so there were no differences in the peak values of the bilateral basal ganglia. We also examined the left-over-right ratio in the peak value and in the rapid-washout ratio in the basal ganglia in the 15 normal subjects. There was no difference in the peak values of the bilateral basal ganglia. The mean rapid-washout ratio was 0.62 ± 0.11 (mean ± SD). The prognoses of these patients three months after onset were as follows: 8 showed a good recovery, 5 had a moderate disability, and 2 had a severe disability. The perfusions on admission were as follows. 10 were hypoperfusions, 3 were hypo + late perfusions, one was a normoperfusion, and one was a late perfusion. There was a tendency for the rapid-washout ratio decrease more in the hypo + late perfusion group than in the other groups. Twelve patients showed an iso-density, while 3 showed a low density, on admission. The ''low-density'' group showed a decrease in the A/N ratio of the peak value. We performed serial dynamic CT in 11 cases. The group with severe disabilities (2 cases) showed a hypo + late perfusion in the initial CT, one case kept a hypo + late perfusion, and another case changed to a hypoperfusion; also, there was a tendency for there to be a poor improvement in the A/N ratio of the peak value in these two ''severe-disability'' patients. (J.P.N.)

  12. A modular neural-network model of the basal ganglia's role in learning and selecting motor behaviours.

    OpenAIRE

    Baldassarre, Gianluca

    2002-01-01

    This work presents a modular neural-network model (based on reinforcement learning actor-critic methods) that tries to capture some of the most relevant known aspects of the role that basal ganglia play in learning and selecting motor behavior related to different goals. The model uses a mixture of experts network for the critic and a hierarchical network with two levels for the actor. Some simulations with the model show that basal ganglia select "chunks" of behavior whose "details" are spec...

  13. Involvement of Basal Ganglia network in motor disabilities induced by typical antipsychotics.

    Directory of Open Access Journals (Sweden)

    Jonathan Chetrit

    Full Text Available BACKGROUND: Clinical treatments with typical antipsychotic drugs (APDs are accompanied by extrapyramidal motor side-effects (EPS such as hypokinesia and catalepsy. As little is known about electrophysiological substrates of such motor disturbances, we investigated the effects of a typical APD, alpha-flupentixol, on the motor behavior and the neuronal activity of the whole basal ganglia nuclei in the rat. METHODS AND FINDINGS: The motor behavior was examined by the open field actimeter and the neuronal activity of basal ganglia nuclei was investigated using extracellular single unit recordings on urethane anesthetized rats. We show that alpha-flupentixol induced EPS paralleled by a decrease in the firing rate and a disorganization of the firing pattern in both substantia nigra pars reticulata (SNr and subthalamic nucleus (STN. Furthermore, alpha-flupentixol induced an increase in the firing rate of globus pallidus (GP neurons. In the striatum, we recorded two populations of medium spiny neurons (MSNs after their antidromic identification. At basal level, both striato-pallidal and striato-nigral MSNs were found to be unaffected by alpha-flupentixol. However, during electrical cortico-striatal activation only striato-pallidal, but not striato-nigral, MSNs were found to be inhibited by alpha-flupentixol. Together, our results suggest that the changes in STN and SNr neuronal activity are a consequence of increased neuronal activity of globus pallidus (GP. Indeed, after selective GP lesion, alpha-flupentixol failed to induce EPS and to alter STN neuronal activity. CONCLUSION: Our study reports strong evidence to show that hypokinesia and catalepsy induced by alpha-flupentixol are triggered by dramatic changes occurring in basal ganglia network. We provide new insight into the key role of GP in the pathophysiology of APD-induced EPS suggesting that the GP can be considered as a potential target for the treatment of EPS.

  14. Competing basal ganglia pathways determine the difference between stopping and deciding not to go.

    Science.gov (United States)

    Dunovan, Kyle; Lynch, Brighid; Molesworth, Tara; Verstynen, Timothy

    2015-01-01

    The architecture of corticobasal ganglia pathways allows for many routes to inhibit a planned action: the hyperdirect pathway performs fast action cancellation and the indirect pathway competitively constrains execution signals from the direct pathway. We present a novel model, principled off of basal ganglia circuitry, that differentiates control dynamics of reactive stopping from intrinsic no-go decisions. Using a nested diffusion model, we show how reactive braking depends on the state of an execution process. In contrast, no-go decisions are best captured by a failure of the execution process to reach the decision threshold due to increasing constraints on the drift rate. This model accounts for both behavioral and functional MRI (fMRI) responses during inhibitory control tasks better than alternative models. The advantage of this framework is that it allows for incorporating the effects of context in reactive and proactive control into a single unifying parameter, while distinguishing action cancellation from no-go decisions. PMID:26402462

  15. Transtorno obsessivo-compulsivo e os gânglios da base Obsessive-compulsive disorder and the basal ganglia

    Directory of Open Access Journals (Sweden)

    Eurípedes Constantino Miguel Filho

    1995-12-01

    Full Text Available O transtorno obsessivo compulsivo (TOC, caracterizado por obsessões e compulsões, foi descrito com frequência aumentada em várias doenças que acometem primariamente of gânglios da base sugerindo que estas estruturas também estivessem acometidas no TOC. Os gânglios da base, que no passado se acreditava estarem implicados apenas no comportamento motor, são, na verdade, importantes em inúmeras outras funções psíquicas como o processamento de vivências cognitivas. Estudos recentes utilizando imagem de ressonância magnética mostraram tendência a diminuição do núcleo caudado em pacientes com TOC. De forma coerente, estudos com neuroimagem funcional, sugerem a implicação de um circuito cerebral envolvendo o córtex órbito-frontal, o giro cíngulo, o núcleo caudado e o tálamo na patofisiologia do TOC. Entre as diversas hipóteses formuladas a partir desses achados, especula-se que um déficit no funcionamento do núcleo caudado levaria a uma filtragem inadequada de preocupações que então estimulariam o córtex órbito-frontal a desencadear ações adaptativas: as compulsões.Obsessive-compulsive disorder (OCD, characterized by obsessions and compulsions, was described as more frequent in patients with primary lesions of the basal ganglia suggesting that these brain structures may be also altered in OCD. The basal ganglia, that were considered important only for the motor control, are known now as crucial for many other mental functions as processing of cognitive experience. Recent studies using magnetic resonance image have found a tendency for smaller caudate nucleus in patients with OCD. Consistently, studies using functional neuroimaging suggest implication of a neurocircuit that includes the orbitalfrontal cortex, the cingulate cortex, caudate nucleus and thalamus in the pathophysiology of OCD. Among several hypotheses formulated to explain these findings, some authors speculated that a deficit of the caudate nucleus

  16. Automatic evaluation of speech rhythm instability and acceleration in dysarthrias associated with basal ganglia dysfunction

    Directory of Open Access Journals (Sweden)

    Jan eRusz

    2015-07-01

    Full Text Available Speech rhythm abnormalities are commonly present in patients with different neurodegenerative disorders. These alterations are hypothesized to be a consequence of disruption to the basal ganglia circuitry involving dysfunction of motor planning, programming and execution, which can be detected by a syllable repetition paradigm. Therefore, the aim of the present study was to design a robust signal processing technique that allows the automatic detection of spectrally-distinctive nuclei of syllable vocalizations and to determine speech features that represent rhythm instability and acceleration. A further aim was to elucidate specific patterns of dysrhythmia across various neurodegenerative disorders that share disruption of basal ganglia function. Speech samples based on repetition of the syllable /pa/ at a self-determined steady pace were acquired from 109 subjects, including 22 with Parkinson's disease (PD, 11 progressive supranuclear palsy (PSP, 9 multiple system atrophy (MSA, 24 ephedrone-induced parkinsonism (EP, 20 Huntington's disease (HD, and 23 healthy controls. Subsequently, an algorithm for the automatic detection of syllables as well as features representing rhythm instability and rhythm acceleration were designed. The proposed detection algorithm was able to correctly identify syllables and remove erroneous detections due to excessive inspiration and nonspeech sounds with a very high accuracy of 99.6%. Instability of vocal pace performance was observed in PSP, MSA, EP and HD groups. Significantly increased pace acceleration was observed only in the PD group. Although not significant, a tendency for pace acceleration was observed also in the PSP and MSA groups. Our findings underline the crucial role of the basal ganglia in the execution and maintenance of automatic speech motor sequences. We envisage the current approach to become the first step towards the development of acoustic technologies allowing automated assessment of rhythm

  17. Models of basal ganglia and cerebellum for sensorimotor integration and predictive control

    Science.gov (United States)

    Jabri, Marwan A.; Huang, Jerry; Coenen, Olivier J. D.; Sejnowski, Terrence J.

    2000-10-01

    This paper presents a sensorimotor architecture integrating computational models of a cerebellum and a basal ganglia and operating on a microrobot. The computational models enable a microrobot to learn to track a moving object and anticipate future positions using a CCD camera. The architecture features pre-processing modules for coordinate transformation and instantaneous orientation extraction. Learning of motor control is implemented using predictive Hebbian reinforcement-learning algorithm in the basal ganglia model. Learning of sensory predictions makes use of a combination of long-term depression (LTD) and long-term potentiation (LTP) adaptation rules within the cerebellum model. The basal ganglia model uses the visual inputs to develop sensorimotor mapping for motor control, while the cerebellum module uses robot orientation and world- coordinate transformed inputs to predict the location of the moving object in a robot centered coordinate system. We propose several hypotheses about the functional role of cell populations in the cerebellum and argue that mossy fiber projections to the deep cerebellar nucleus (DCN) could play a coordinate transformation role and act as gain fields. We propose that such transformation could be learnt early in the brain development stages and could be guided by the activity of the climbing fibers. Proprioceptor mossy fibers projecting to the DCN and providing robot orientation with respect to a reference system could be involved in this case. Other mossy fibers carrying visual sensory input provide visual patterns to the granule cells. The combined activities of the granule and the Purkinje cells store spatial representations of the target patterns. The combinations of mossy and Purkinje projections to the DCN provide a prediction of the location of the moving target taking into consideration the robot orientation. Results of lesion simulations based on our model show degradations similar to those reported in cerebellar lesion

  18. Re-evaluation of the functional anatomy of the basal ganglia in normal and Parkinsonian states.

    Science.gov (United States)

    Levy, R; Hazrati, L N; Herrero, M T; Vila, M; Hassani, O K; Mouroux, M; Ruberg, M; Asensi, H; Agid, Y; Féger, J; Obeso, J A; Parent, A; Hirsch, E C

    1997-01-01

    In the late 1980s, a functional and anatomical model of basal ganglia organization was proposed in order to explain the clinical syndrome of Parkinson's disease. According to this model, the pathological overactivity observed in the subthalamic nucleus and the output station of the basal ganglia plays a crucial role in the pathophysiology of the motor signs of Parkinson's disease. The hyperactivity of subthalamic neurons in Parkinsonism is viewed as a direct consequence of a pathological hypoactivity of the external segment of the pallidum. This article reviews recent data from different experimental approaches that challenge the established model of basal ganglia organization by reinterpreting the functional interaction between the external segment of the pallidum and the subthalamic nucleus in both the normal and pathological state. Indeed, recent neurobiochemical studies have rather unexpectedly shown that the GABAergic and metabolic activities of the external pallidum are not decreased in human and non-human primates with Parkinsonism. This absence of any decrease in activity might be explained by the functionally antagonistic influences of the striatal and subthalamic afferences within the external pallidum, as suggested by several anatomical studies. In addition, there are clues from electrophysiological studies to suggest that the hyperactivity found in the subthalamic neurons in Parkinsonism may not depend solely on the level of activity in the external pallidum. In such a framework, the hyperactivity of the subthalamic neurons would have to be explained, at least in part, by other sources of excitation or disinhibition. However, any explanation for the origin of the subthalamic overactivity in Parkinsonism remains speculative.

  19. Dopamine-transporter SPECT and Dopamine-D2-receptor SPECT in basal ganglia diseases

    International Nuclear Information System (INIS)

    The basal ganglia comprise a group of subcortical nuclei, which are essential for motor control. Dysfunction of these areas, especially in dopaminergic transmission, results in disordered movement and neurological diseases such as Parkinson's disease, Wilson's disease, or Huntington disease. Positron emission tomography and single photon emission computed tomography (SPECT) have enhanced the understanding of the underlying pathophysiology, but they much more contribute to the early differential diagnosis of patients suffering from Parkinsonian syndrome in routine care. The present article provides dopamine transporter and D2 receptor SPECT findings in selected movement disorders. (orig.)

  20. A neuromotor model of handwriting generation highlighting the role of basal ganglia

    OpenAIRE

    Garipelli, Gangadhar

    2006-01-01

    Handwriting (HW), unlike reaching or walking, is a high-level motor activity, engaging large parts of cortical and sub-cortical regions that include supplementary motor area(SMA), premotor area(PM), primary motor area(M1), basal ganglia(BG), cerebellum, spinal cord etc. Since each of these regions contributes to HW output in its own unique fashion, pathology of any of these regions is manifest as characteristic features in HW. For example, in Parkinson's disease, a disorder of BG, HW is marke...

  1. Dopamine Transporter Density of the Basal Ganglia Assessed with I-123 IPT SPECT in Patients with Obsessive-Compulsive Disorder

    International Nuclear Information System (INIS)

    It has been suggested that dopamine as well as serotonin is associated with the pathophysiology of obsessive-compulsive disorder (OCD). Thus, many studies about brain regions associated with dopamine in OCD have been performed. In the present study, we investigated the DAT density of the basal ganglia using iodine-123 labelled N-(3-iodopropen-2-yl) - 2beta - carbomethoxy - 3beta - (4 - chloropheny1) tropane (I-123 IPT) single-photon emission tomography (SPECT) in patients with OCD and evaluated the activity of the presynaptic dopamine function in patients with OCD. Fifteen patients with OCD and nineteen normal control adults were included in the study. We performed brain SPET 2 hours after the intravenous administration of I-123 IPT and carried out both quantitative and qualitative analyses using the obtained SPET data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. We then investigated the correlation between the severity scores of OCD symptoms assessed with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the specific/non-specific DAT binding ratio of the basal ganglia. Patients with OCD showed a significantly increased specific/non-specific DAT binding ratio in right basal ganglia compared with normal control adults and an increased tendency in the specific/non-specific DAT binding ratio in left basal ganglia. No significant correlation was found between the total scores of the Y-BOCS and the specific/non-specific DAT binding ratio of the basal ganglia. Our findings suggest that the dopaminergic neurotransmitter system of the basal ganglia in patients with OCD plays an important role in fronto-subcortical circuit well-known as the pathophysiological mechanism of OCD

  2. Dopamine transporter density of basal ganglia assessed with [123I]IPT SPET in obsessive-compulsive disorder

    International Nuclear Information System (INIS)

    It has been suggested that dopamine, as well as serotonin, is associated with the pathophysiology of obsessive-compulsive disorder (OCD). Thus, many studies have been performed on brain regions associated with dopamine in patients with OCD. In the present study, we investigated the DAT density of the basal ganglia using iodine-123 labelled N-(3-iodopropen-2-yl)-2β-carbomethoxy-3β-(4-chlorophenyl) tropane ([123I]IPT) single-photon emission tomography (SPET) and evaluated the activity of the presynaptic dopamine function in patients with OCD. Fifteen patients with OCD and 19 normal control adults were included in the study. We performed brain SPET 2 h after the intravenous administration of [123I]IPT and carried out both quantitative and qualitative analyses using the obtained SPET data, which were reconstructed for the assessment of the specific/non-specific dopamine transporter (DAT) binding ratio in the basal ganglia. We then investigated the correlation between the severity scores of OCD symptoms assessed with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the specific/non-specific DAT binding ratio of the basal ganglia. Compared with normal control adults, patients with OCD showed a significantly increased specific/non-specific DAT binding ratio in the right basal ganglia and a tendency towards an increased specific/non-specific DAT binding ratio in the left basal ganglia. No significant correlation was found between the total scores on the Y-BOCS and the specific/non-specific DAT binding ratio of the basal ganglia. These findings suggest that the dopaminergic neurotransmitter system of the basal ganglia in patients with OCD could be involved in the pathophysiology of OCD. (orig.)

  3. Dopamine Transporter Density of the Basal Ganglia Assessed with I-123 IPT SPECT in Patients with Obsessive-Compulsive Disorder

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, W. K.; Ryu, Y. H.; Yoon, M. J.; Kim, C. H.; Chun, K. A.; Lee, J. D. [College of Medicine, Univ. of Yonsei, Seoul (Korea, Republic of); Jee, D. Y. [College of Medicine, Univ. of Inhwa, Seoul (Korea, Republic of); Choi, T. H. [Korea Cancer Center Hospital, Seoul (Korea, Republic of)

    2003-07-01

    It has been suggested that dopamine as well as serotonin is associated with the pathophysiology of obsessive-compulsive disorder (OCD). Thus, many studies about brain regions associated with dopamine in OCD have been performed. In the present study, we investigated the DAT density of the basal ganglia using iodine-123 labelled N-(3-iodopropen-2-yl) - 2beta - carbomethoxy - 3beta - (4 - chloropheny1) tropane (I-123 IPT) single-photon emission tomography (SPECT) in patients with OCD and evaluated the activity of the presynaptic dopamine function in patients with OCD. Fifteen patients with OCD and nineteen normal control adults were included in the study. We performed brain SPET 2 hours after the intravenous administration of I-123 IPT and carried out both quantitative and qualitative analyses using the obtained SPET data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. We then investigated the correlation between the severity scores of OCD symptoms assessed with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the specific/non-specific DAT binding ratio of the basal ganglia. Patients with OCD showed a significantly increased specific/non-specific DAT binding ratio in right basal ganglia compared with normal control adults and an increased tendency in the specific/non-specific DAT binding ratio in left basal ganglia. No significant correlation was found between the total scores of the Y-BOCS and the specific/non-specific DAT binding ratio of the basal ganglia. Our findings suggest that the dopaminergic neurotransmitter system of the basal ganglia in patients with OCD plays an important role in fronto-subcortical circuit well-known as the pathophysiological mechanism of OCD.

  4. Dopamine transporter density of basal ganglia assessed with [{sup 123}I]IPT SPET in obsessive-compulsive disorder

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chan-Hyung; Cheon, Keun-Ah; Lee, Hong-Shick [Department of Psychiatry, College of Medicine, Yonsei University, 146-92 Dogokdong, 135-720, Gangnam-Gu, Seoul (Korea); Koo, Min-Seong [Department of Psychiatry, College of Medicine, Kwandong University, Kangwon (Korea); Ryu, Young-Hoon; Lee, Jong-Doo [Division of Nuclear Medicine, Department of Radiology, College of Medicine, Yonsei University, Seoul (Korea)

    2003-12-01

    It has been suggested that dopamine, as well as serotonin, is associated with the pathophysiology of obsessive-compulsive disorder (OCD). Thus, many studies have been performed on brain regions associated with dopamine in patients with OCD. In the present study, we investigated the DAT density of the basal ganglia using iodine-123 labelled N-(3-iodopropen-2-yl)-2{beta}-carbomethoxy-3{beta}-(4-chlorophenyl) tropane ([{sup 123}I]IPT) single-photon emission tomography (SPET) and evaluated the activity of the presynaptic dopamine function in patients with OCD. Fifteen patients with OCD and 19 normal control adults were included in the study. We performed brain SPET 2 h after the intravenous administration of [{sup 123}I]IPT and carried out both quantitative and qualitative analyses using the obtained SPET data, which were reconstructed for the assessment of the specific/non-specific dopamine transporter (DAT) binding ratio in the basal ganglia. We then investigated the correlation between the severity scores of OCD symptoms assessed with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the specific/non-specific DAT binding ratio of the basal ganglia. Compared with normal control adults, patients with OCD showed a significantly increased specific/non-specific DAT binding ratio in the right basal ganglia and a tendency towards an increased specific/non-specific DAT binding ratio in the left basal ganglia. No significant correlation was found between the total scores on the Y-BOCS and the specific/non-specific DAT binding ratio of the basal ganglia. These findings suggest that the dopaminergic neurotransmitter system of the basal ganglia in patients with OCD could be involved in the pathophysiology of OCD. (orig.)

  5. The microdissection in cerebrum insula and basal ganglia region%大脑岛叶与基底节区的显微解剖

    Institute of Scientific and Technical Information of China (English)

    冯三平

    2012-01-01

    Objective To have an intimate knowledge of the corresponding anatomic correlation among cerebrum insular cortex, basal ganglia region and internal capsule in order to provide some important anatomic basis for cleaning hypertensive hemorrhage in basal ganglia region via lateral fissure-insular approach. Methods Dissection and measurement were performed in insular lobe and basal ganglia region of 10 adult cadaveric heads ( 20 hemispheres ). Results The insular cortex,viewed from a lateral side, was triangular ( widest superiorly and narrowest inferiorly ), with an apical elevation that gave it an overall pyramidal configuration. The insular lobe was located in the depth of the sylvian fissure, covered by the frontal, parietal and temporal, and the depths covered the deep basal nuclei, internal capsule and thalamus. On the middle horizontal section of the insular lobe,the sulci and gyri of insular lobe were all corresponding inward the putamen, in which the middle and posterior short gyri were corresponding the widest part of the putamen and genu of internal capsule. The central sulcus of insula was the closest distance to the putamen, corresponding inward posterior part of putamen and posterior limb of internal capsule as well as thalamus. Conclusion To have an intimate knowledge of the anatomy of the insular lobe and basal ganglia region is helpful to clean intracerebral hematomas in basal ganglia region via sylvian fissure insular surgical approach, and can further reduce the incidence of complications caused by internal capsule injury.%目的 熟悉大脑岛叶和基底节区的解剖,探讨岛叶皮质和基底节、内囊等的对应解剖关系,为经外侧裂-岛叶入路,清除高血压基底节出血时,提供一些重要的解剖依据.方法 对10例(20侧)成人尸头标本进行岛叶和基底节区的解剖与测量.结果 从侧面看,岛叶皮层是一个上宽,下窄的三角形,加上岛顶的高度,整体看岛叶就是一个金字塔结构.岛叶

  6. Dopamine transporter density of the basal ganglia in children with attention deficit hyperactivity disorder assessed with I-123 IPT SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Ryu, Won Gee; Kim, Tae Hoon; Ryu, Young Hoon; Yun, Mi Jin; Lee, Jong Doo; Cheon, Keun Ah [College of Medicine, Yonsei Univ., Seoul (Korea, Republic of); Chi, Dae Yoon [College of Medicine, Inha Univ., Incheon (Korea, Republic of); Kim, Jong Ho; Choi, Tae Hyun [School of Medicine, Gachon Univ., Gachon (Korea, Republic of)

    2003-08-01

    Attention deficit hyperactivity disorder (ADHD) has been known as psychiatric disorder in childhood associated with dopamine dysregulation. In present study, we investigated changes in dopamine transporter (DAT) density of the basal ganglias using I-123 N-(3-iodopropen-2-yl) -2-carbomethoxy-3beta-(4-chlorphenyl) tropane (I-123 IPT) SPECT in children with ADHD before and after methylphenidate treatment. Nine drug-naive children with ADHD and seven normal children were included in the study. We performed brain SPECT two hours after the intravenous administration of I-123 IPT and made both quantitative and qualitative analyses using the obtained SPECT data, which were reconstructed for the assessment of specific/nonspecific DAT binding ratios in the basal ganglia. All children with ADHD reperformed (123I)IPT SPECT after treatment with methylphenidate (0.7mg/kg/d) during about 8 weeks. SPECT data reconstructed for the assessment of specific/nonspecific DAT binding ratio of the basal ganglia were compared between before and after treatment methyphenidate. We investigated correlation between the change of ADHD symptom severity assessed with ADHD rating scale-IV and specific/nonspecific DAT binding ratio of basal ganglia. Children with ADHD had a significantly greater specific/nonspecific DAT binding ratio of the basal ganglia comparing to normal children (Right : z = 2.057, p = 0.041 ; Left : z = 2.096, p = 0.032). Under treatment with methylphenidate in all children with ADHD, specific/nonspecific DAT binding ratio of both ganglia decreased significantly greater than before treatment with methylphenidate (Right : t = 3.239, p = 0.018 ; Left : t = 3.133, p 0.020). However, no significant correlation between the change of ADHD symptom severity scores and specific/nonspecific DAT binding ratio of the basal ganglia were found. These findings support the complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD.

  7. The basal ganglia and rule-governed language use: evidence from vascular and degenerative conditions.

    Science.gov (United States)

    Longworth, C E; Keenan, S E; Barker, R A; Marslen-Wilson, W D; Tyler, L K

    2005-03-01

    The Declarative/Procedural Model of Pinker, Ullman and colleagues claims that the basal ganglia are part of a fronto-striatal procedural memory system which applies grammatical rules to combine morphemes (the smallest meaningful units in language) into complex words (e.g. talk-ed, talk-ing). We tested this claim by investigating whether striatal damage or loss of its dopaminergic innervation is reliably associated with selective regular past tense deficits in patients with subcortical cerebrovascular damage, Parkinson's disease or Huntington's disease. We focused on past tense morphology since this allows us to contrast the regular past tense (jump-jumped), which is rule-based, with the irregular past tense (sleep-slept), which is not. We used elicitation and priming tasks to test patients' ability to comprehend and produce inflected forms. We found no evidence of a consistent association between striatal dysfunction and selective impairment of regular past tense morphology, suggesting that the basal ganglia are not essential for processing the regular past tense as a sequence of morphemes, either in comprehension or production, in contrast to the claims of the Declarative/Procedural Model. All patient groups showed normal activation of semantic and morphological representations in comprehension, despite difficulties suppressing semantically appropriate alternatives when trying to inflect novel verbs. This is consistent with previous reports that striatal dysfunction spares automatic activation of linguistic information, but disrupts later language processes that require inhibition of competing alternatives. PMID:15659423

  8. Role of movement in long-term basal ganglia changes: implications for abnormal motor responses

    Directory of Open Access Journals (Sweden)

    Nicola eSimola

    2013-10-01

    Full Text Available Abnormal involuntary movements and dyskinesias elicited by drugs that stimulate dopamine receptors in the basal ganglia are a major issue in the management of Parkinson’s disease (PD. Preclinical studies in dopamine-denervated animals have contributed to the modeling of these abnormal movements, but the precise neurochemical and functional mechanisms underlying these untoward effects are still elusive. It has recently been suggested that the performance of movement may itself promote the later emergence of drug-induced motor complications, by favoring the generation of aberrant motor memories in the dopamine-denervated basal ganglia. Our recent results from hemiparkinsonian rats subjected to the priming model of dopaminergic stimulation are in agreement with this and may constitute a useful model to study the early neurochemical events underling dyskinesia. These results demonstrate that early performance of movement is crucial for the manifestation of sensitized rotational behavior, indicative of an abnormal motor response, and neurochemical modifications in selected striatal neurons following a dopaminergic challenge. Building on this evidence, this paper discusses the possible role of movement performance in drug-induced motor complications, with a look at the implications for PD management.

  9. A case of vitamin B12 deficiency with involuntary movements and bilateral basal ganglia lesions.

    Science.gov (United States)

    Kitamura, Taisuke; Gotoh, Seiji; Takaki, Hayato; Kiyuna, Fumi; Yoshimura, Sohei; Fujii, Kenichiro

    2016-07-28

    An 86-year-old woman with a one-year history of dementia was admitted to our hospital complaining of loss of appetite, hallucinations, and disturbance of consciousness. She gradually presented with chorea-like involuntary movements of the extremities. Diffusion-weighted magnetic resonance imaging (MRI) showed bilateral symmetrical hyperintense signals in the basal ganglia. The serum vitamin B12 level was below the lower detection limit of 50 pg/ml. The homocysteine level was markedly elevated at 115.8 nmol/ml. Anti-intrinsic factor and anti-parietal cell antibody tests were positive. Gastrointestinal endoscopy revealed atrophic gastritis. The patient was diagnosed with encephalopathy due to vitamin B12 deficiency caused by pernicious anemia. Involuntary movements and MRI abnormalities improved with parenteral vitamin B12 supplementation. Bilateral basal ganglia lesions are rare manifestations of adult vitamin B12 deficiency. The present case is considered valuable in identifying the pathophysiology of involuntary movement due to vitamin B12 deficiency. PMID:27356735

  10. Neurotensin receptor binding levels in basal ganglia are not altered in Huntington's chorea or schizophrenia

    International Nuclear Information System (INIS)

    Autoradiographic techniques were used to examine the distribution and levels of neurotensin receptor binding sites in the basal ganglia and related regions of the human brain. Monoiodo (125I-Tyr3)neurotensin was used as a ligand. High amounts of neurotensin receptor binding sites were found in the substantia nigra pars compacta. Lower but significant quantities of neurotensin receptor binding sites characterized the caudate, putamen, and nucleus accumbens, while very low quantities were seen in both medial and lateral segments of the globus pallidus. In Huntington's chorea, the levels of neurotensin receptor binding sites were found to be comparable to those of control cases. Only slight but not statistically significant decreases in amounts of receptor binding sites were detected in the dorsal part of the head and in the body of caudate nucleus. No alterations in the levels of neurotensin receptor binding sites were observed in the substantia nigra pars compacta and reticulata. These results suggest that a large proportion of neurotensin receptor binding sites in the basal ganglia are located on intrinsic neurons and on extrinsic afferent fibers that do not degenerate in Huntington's disease

  11. Trigeminal-basal ganglia interaction: control of sensory-motor gating and positive reinforcement.

    Science.gov (United States)

    Schwarting, R K; Elstermeier, F; Francke, W; Huston, J P

    1991-02-01

    Functional interactions between the basal ganglia and the perioral area were analyzed by means of electrical brain stimulation in the rat. The first experiment showed that unilateral stimulation of the substantia nigra sensitized the contralateral perioral area for a biting reflex upon its tactile stimulation. This biting reflex consists of lip withdrawal, orienting towards and biting into the stimulus source. The same sites in the substantia nigra also produced electrical self-stimulation using bar-pressing as the operant. A positive correlation was found between threshold currents for biting and for self-stimulation. However, the current levels necessary for reinforcement were considerably higher than those to facilitate the biting reflex. In the second experiment, it was found that manipulation of the perioral area by unilateral vibrissae removal reduced the rate of electrical self-stimulation in the substantia nigra. This effect was lateralized, depended on time after vibrissae removal, and could be reversed by systemic injections of the dopamine receptor agonist apomorphine. These results, which provide evidence for a reciprocal interaction between the basal ganglia and the perioral area, are discussed with respect to mechanisms of sensory-motor gating, motivation and reinforcement.

  12. Genetic screening and functional characterization of PDGFRB mutations associated with Basal Ganglia Calcification of Unknown Etiology

    Science.gov (United States)

    Sanchez-Contreras, Monica; Baker, Matthew C.; Finch, NiCole A.; Nicholson, Alexandra; Wojtas, Aleksandra; Wszolek, Zbigniew K.; Ross, Owen A.; Dickson, Dennis W.; Rademakers, Rosa

    2014-01-01

    Three causal genes for Idiopathic Basal Ganglia Calcification (IBGC) have been identified. Most recently, mutations in PDGFRB, encoding a member of the platelet-derived growth factor receptor family type β, and PDGFB, encoding PDGF-B, the specific ligand of PDGFRβ, were found implicating the PDGF-B/PDGFRβ pathway in abnormal brain calcification. In this study we aimed to identify and study mutations in PDGFRB and PDGFB in a series of 26 patients from the Mayo Clinic Florida Brain Bank with moderate to severe basal ganglia calcification (BCG) of unknown etiology. No mutations in PDGFB were found. However, we identified one mutation in PDGFRB, p.R695C located in the tyrosine kinase domain, in one BGC patient. We further studied the function of p.R695C mutant PDGFRβ and two previously reported mutants, p.L658P and p.R987W PDGFRβ in cell culture. We show that, in response to PDGF-BB stimulation, the p.L658P mutation completely suppresses PDGFRβ autophosphorylation whereas the p.R695C mutation results in partial loss of autophosphorylation. For the p.R987W mutation, our data suggest a different mechanism involving reduced protein levels. These genetic and functional studies provide the first insight into the pathogenic mechanisms associated with PDGFRB mutations and provide further support for a pathogenic role of PDGFRB mutations in BGC. PMID:24796542

  13. Longitudinal Assessment of Motor Recovery of Contralateral Hand after Basal Ganglia Infarction Using Functional Magnetic Resonance Imaging

    Directory of Open Access Journals (Sweden)

    Yue Fu

    2016-01-01

    Full Text Available We used functional fMRI to study the brain activation during active finger movements at different time points during the recovery phase following basal ganglia infarction. Four hemiplegic patients with basal ganglia infarction were serially evaluated at different time points spanning the acute and chronic phase using fMRI. To evaluate motor recovery, the patients were asked to perform functional tasks arranged in a block design manner with their hand. On follow-up (chronic phase, three patients achieved significant recovery of motor function of affected limbs. Activation of bilateral sensorimotor cortex (SMC was observed in two of these patients, while activation of cerebellum was observed in all patients. No remarkable recovery of motor function was noted in one patient with left basal ganglia infarction. In this patient, the activation domain was located in SMC of both sides in acute phase and in ipsilateral SMC in chronic phase. Contralateral SMC appears to be involved in the functional rehabilitation following basal ganglia infarction. The cerebellum may act as an intermediary during functional recovery following basal ganglia infarction. The activation domain associated with active finger movement may be bilateral in acute phase; one patient was ipsilateral in the chronic stage.

  14. DISTRIBUTION OF PARVALBUMIN,CALBINDIN-D28 AND CALRETININ IMMUNOREACTIVE NEURONS AND FIBERS IN THE MONKEY BASAL GANGLIA

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Objective To investigate the cellular localization of parvalbumin(PV),calbindin-D28K(CB)and clretinin(CR)in the monkey basal ganglia.Methods Immunocytochemical technique was used to detect PV,CB and CR immunoreactivity in the basal ganglia.Results In the striatum,CB labeled medium-sized spiny projection neuronsshereas PV and CR marked two separate classes of aspiny interneurons,The striatal matrix compartment was markedly enriched with CB while striatal patches displayed a CR-ich neuropil,In the pallidum,virtually all neurons contained PV but none express CB,CR occured only in a small subpopulation of large and small pallidal neurons.In the subthalamic nucleus,there existed a multitude of PV-positive cells and fibers but the number of CR and CB-postive neuronal elements was small,In the substantia nigra/ventral tegmental area complex.CB and CR occured principally in dopaminergic neurons of the dorsal tier of the pars compacta and in those of the ventral tegmental area.PV was strickly confined to the GABAergic neurons of the pars reticular and lateralis.CB-rich fibers abounded in the pars reticular and lateralis,while CR-positive axons were confined to the pars compacta.Conclusion:CB and PV were distributed according to a strikingly complementary pattern in primate basal ganglia,and the use of CB and PV immunocytochemistry may be considered as an excellent tool to define distinct chemoarchitectonic and functional domains within the complex organization of the basal ganglia ,CR was less ubiquitous but occured in small basal ganglia components where it labeled distinct subsets of neurons.Such highly specific patterns of distribution indicate that CB,PV and CR may work in synery within primate basal ganglia.

  15. Functional neuroanatomy of the basal ganglia as studied by dual-probe microdialysis

    International Nuclear Information System (INIS)

    Dual probe microdialysis was employed in intact rat brain to investigate the effect of intrastriatal perfusion with selective dopamine D1 and D2 receptor agonists and with c-fos antisense oligonucleotide on (a) local GABA release in the striatum; (b) the internal segment of the globus pallidus and the substantia nigra pars reticulata, which is the output site of the strionigral GABA pathway; and (c) the external segment of the globus pallidus, which is the output site of the striopallidal GABA pathway. The data provide functional in vivo evidence for a selective dopamine D1 receptor-mediated activation of the direct strionigral GABA pathway and a selective dopamine D2 receptor inhibition of the indirect striopallidal GABA pathway and provides a neuronal substrate for parallel processing in the basal ganglia regulation of motor function. Taken together, these findings offer new therapeutic strategies for the treatment of dopamine-linked disorders such as Parkinson's disease, Huntington's disease, and schizophrenia

  16. Structural findings in the basal ganglia in genetically determined and idiopathic Parkinson's disease

    DEFF Research Database (Denmark)

    Reetz, Kathrin; Gaser, Christian; Klein, Christine;

    2009-01-01

    A bilateral compensatory increase of basal ganglia (BG) gray matter value (GMV) was recently demonstrated in asymptomatic Parkin mutation carriers, who likely have an increased risk to develop Parkinson's disease (PD). We hypothesized BG morphological changes in symptomatic Parkin mutation carriers...... (sPARKIN-MC) and idiopathic PD patients (iPD) after the occurrence of PD symptoms, reflecting the breakdown of compensatory mechanisms. Nine sPARKIN-MC, 14 iPD, and 24 controls were studied clinically and with voxel-based morphometry. Analysis of variance revealed mainly BG decrease of GMV in sPARKIN......-MC and to a lesser extent in iPD. However, a slight increase in GMV was also found in the right globus pallidus externus in sPARKIN-MC and in the right putamen in iPD. This may reflect a structural correlate of functional compensation that can only partially be maintained when nigrostriatal neurodegeneration becomes...

  17. Basal ganglia dysfunction in idiopathic REM sleep behaviour disorder parallels that in early Parkinson’s disease

    Science.gov (United States)

    Rolinski, Michal; Griffanti, Ludovica; Piccini, Paola; Roussakis, Andreas A.; Szewczyk-Krolikowski, Konrad; Menke, Ricarda A.; Quinnell, Timothy; Zaiwalla, Zenobia; Klein, Johannes C.; Mackay, Clare E.

    2016-01-01

    See Postuma (doi:10.1093/aww131) for a scientific commentary on this article. Resting state functional magnetic resonance imaging dysfunction within the basal ganglia network is a feature of early Parkinson’s disease and may be a diagnostic biomarker of basal ganglia dysfunction. Currently, it is unclear whether these changes are present in so-called idiopathic rapid eye movement sleep behaviour disorder, a condition associated with a high rate of future conversion to Parkinson’s disease. In this study, we explore the utility of resting state functional magnetic resonance imaging to detect basal ganglia network dysfunction in rapid eye movement sleep behaviour disorder. We compare these data to a set of healthy control subjects, and to a set of patients with established early Parkinson’s disease. Furthermore, we explore the relationship between resting state functional magnetic resonance imaging basal ganglia network dysfunction and loss of dopaminergic neurons assessed with dopamine transporter single photon emission computerized tomography, and perform morphometric analyses to assess grey matter loss. Twenty-six patients with polysomnographically-established rapid eye movement sleep behaviour disorder, 48 patients with Parkinson’s disease and 23 healthy control subjects were included in this study. Resting state networks were isolated from task-free functional magnetic resonance imaging data using dual regression with a template derived from a separate cohort of 80 elderly healthy control participants. Resting state functional magnetic resonance imaging parameter estimates were extracted from the study subjects in the basal ganglia network. In addition, eight patients with rapid eye movement sleep behaviour disorder, 10 with Parkinson’s disease and 10 control subjects received 123I-ioflupane single photon emission computerized tomography. We tested for reduction of basal ganglia network connectivity, and for loss of tracer uptake in rapid eye movement

  18. Task-Rest Modulation of Basal Ganglia Connectivity in Mild to Moderate Parkinson’s Disease

    Science.gov (United States)

    Müller-Oehring, Eva M.; Sullivan, Edith V.; Pfefferbaum, Adolf; Huang, Neng C.; Poston, Kathleen L.; Bronte-Stewart, Helen M.; Schulte, Tilman

    2014-01-01

    Parkinson’s disease (PD) is associated with abnormal synchronization in basal ganglia-thalamo-cortical loops. We tested whether early PD patients without demonstrable cognitive impairment exhibit abnormal modulation of functional connectivity at rest, while engaged in a task, or both. PD and healthy controls underwent two functional MRI scans: a resting-state scan and a Stroop Match-to-Sample task scan. Rest-task modulation of basal ganglia (BG) connectivity was tested using seed-to-voxel connectivity analysis with task and rest time series as conditions. Despite substantial overlap of BG–cortical connectivity patterns in both groups, connectivity differences between groups had clinical and behavioral correlates. During rest, stronger putamen–medial parietal and pallidum–occipital connectivity in PD than controls was associated with worse task performance and more severe PD symptoms suggesting that abnormalities in resting-state connectivity denote neural network dedifferentiation. During the executive task, PD patients showed weaker BG-cortical connectivity than controls, i.e., between caudate–supramarginal gyrus and pallidum–inferior prefrontal regions, that was related to more severe PD symptoms and worse task performance. Yet, task processing also evoked stronger striatal–cortical connectivity, specifically between caudate–prefrontal, caudate–precuneus, and putamen–motor/premotor regions in PD relative to controls, which was related to less severe PD symptoms and better performance on the Stroop task. Thus, stronger task-evoked striatal connectivity in PD demonstrated compensatory neural network enhancement to meet task demands and improve performance levels. fMRI-based network analysis revealed that despite resting-state BG network compromise in PD, BG connectivity to prefrontal, premotor, and precuneus regions can be adequately invoked during executive control demands enabling near normal task performance. PMID:25280970

  19. Clinical studies of the calcification of the basal ganglia as disclosed by computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Node, Yoji; Nakazawa, Shozo (Nippon Medical School, Tokyo)

    1983-04-01

    One hundred and twenty-nine of the 12,645 patients (1.0%) were found to have attenuating changes suggesting calcification of the basal ganglia. Thirty-seven of those patients were male and 92 were female. The calcification was bilateral and grossly symmetric in 108 of these patients (83.7%), while it was unilateral in 21 (16.3%). In the unilaterally located cases, 15 were on the left side and 6 were on the right side. In 128 of these patients (99.2%), calcification was located in the globus pallidus. Only one patient, whose diagnosis was hypoparathyroidism, had calcification in both the globus pallidus and the head of the caudate nucleus. The patients' ages ranged from 10 to 85 years (mean, 58), but 88.4% of the patients were more than 40 years old at the time of the CT scanning. The attenuation values of the lesions varied from 35 to 375 EMI units (mean, 55.7). Skull radiographs were performed in 120 of the 129 patients. Calcification was detected in only one patient, a 76-year-old woman, whose diagnosis was myasthenia gravis. The clinical diagnoses of the 129 patients were as follows: 37, headache; 22, cerebrovascular diseases (19, occlusive cerebrovascular diseases); 20, vertigo and/or tinnitus; 12, psychiatric disorders; 5, Parkinson's Syndrome; 2, hypopara thyroidism; 2, Fahr's disease; 2, familial basal ganglia calcification; 2, epilepsy, and 25, miscellaneous (including carcinoma, brain tumor, and trauma). Nervous system abnormalities were observed in 41 of the 129 patients (31.2%). Mental signs, such as disturbance of recent memory, mental retardation, and dementia, were noted in 14 patients. Movement disorders were noted in 13 patients. Other nervous-system abnormalities were sensory disturbances (5 patients) and seizures (4 patients). Abnormal EEG activities were noted in 9 patients; three patients showed epileptic activity, and six had a pathologically slow rhythm.

  20. DISTRIBUTION OF PARVALBUMIN, CALBINDIN-D28 AND CALRETININ IMMUNOREACTIVE NEURO NS AND FIBERS IN THE MONKEY BASAL GANGLIA

    Institute of Scientific and Technical Information of China (English)

    刘健; 张巧俊

    2002-01-01

    Objective To investigate the cellular localization of parvalbumin (PV), calbindin-D28k (CB) and calretinin (CR) in the monkey basal ganglia.Methods Immunocytochemica l technique was used to detect PV,CB and CR immunoreactivity in the basal gangl ia. Results In the striatum, CB labeled medium-sized spin y projection neurons whereas PV and CR marked two separate classes of aspiny int erneurons. The striatal matrix compartment was markedly enriched with CB while s triatal patches displayed a CR-rich neuropil. In the pallidum, virtually all ne u rons contained PV but none express CB. CR occured only in a small subpopulation of large and small pallidal neurons. In the subthalamic nucleus, there existed a multitude of PV-positive cells and fibers but the number of CR and CB-positiv e neuronal elements was small. In the substantia nigra / ventral tegmental area co mplex, CB and CR occured principally in dopaminergic neurons of the dorsal tier of the pars compacta and in those of the ventral tegmental area. PV was strickly confined to the GABAergic neurons of the pars reticular and lateralis. CB-rich fibers abounded in the pars reticular and lateralis, while CR-positive axons we re confined to the pars compacta. Conclusion CB and PV were di stributed accordin g to a strikingly complementary pattern in primate basal ganglia, and the use of CB and PV immunocytochemistry may be considered as an excellent tool to define dist inct chemoarchitectonic and functional domains within the complex organization o f the basal ganglia. CR was less ubiquitous but occured in small basal ganglia c omponents where it labeled distinct subsets of neurons. Such highly specific pat terns of distribution indicate that CB, PV and CR may work in synery within prim ate basal ganglia.

  1. Singing-Related Neural Activity Distinguishes Four Classes of Putative Striatal Neurons in the Songbird Basal Ganglia

    OpenAIRE

    Goldberg, Jesse H.; Fee, Michale S

    2010-01-01

    The striatum—the primary input nucleus of the basal ganglia—plays a major role in motor control and learning. Four main classes of striatal neuron are thought to be essential for normal striatal function: medium spiny neurons, fast-spiking interneurons, cholinergic tonically active neurons, and low-threshold spiking interneurons. However, the nature of the interaction of these neurons during behavior is poorly understood. The songbird area X is a specialized striato-pallidal basal ganglia nuc...

  2. Basal ganglia volumes in drug-naive first-episode schizophrenia patients before and after short-term treatment with either a typical or an atypical antipsychotic drug

    DEFF Research Database (Denmark)

    Glenthoj, Andreas; Glenthøj, Birte Yding; Mackeprang, Torben;

    2007-01-01

    The present study examined basal ganglia volumes in drug-naive first-episode schizophrenic patients before and after treatment with either a specific typical or atypical antipsychotic compound. Sixteen antipsychotic drug-naive and three minimally medicated first-episode schizophrenic patients and...... in caudate volume in patients suggests intrinsic basal ganglia pathology in schizophrenia, most likely of neurodevelopmental origin....

  3. How preparation changes the need for top-down control of the basal ganglia when inhibiting premature actions.

    Science.gov (United States)

    Jahfari, Sara; Verbruggen, Frederick; Frank, Michael J; Waldorp, Lourens J; Colzato, Lorenza; Ridderinkhof, K Richard; Forstmann, Birte U

    2012-08-01

    Goal-oriented signals from the prefrontal cortex gate the selection of appropriate actions in the basal ganglia. Key nodes within this fronto-basal ganglia action regulation network are increasingly engaged when one anticipates the need to inhibit and override planned actions. Here, we ask how the advance preparation of action plans modulates the need for fronto-subcortical control when a planned action needs to be withdrawn. Functional magnetic resonance imaging data were collected while human participants performed a stop task with cues indicating the likelihood of a stop signal being sounded. Mathematical modeling of go trial responses suggested that participants attained a more cautious response strategy when the probability of a stop signal increased. Effective connectivity analysis indicated that, even in the absence of stop signals, the proactive engagement of the full control network is tailored to the likelihood of stop trial occurrence. Importantly, during actual stop trials, the strength of fronto-subcortical projections was stronger when stopping had to be engaged reactively compared with when it was proactively prepared in advance. These findings suggest that fronto-basal ganglia control is strongest in an unpredictable environment, where the prefrontal cortex plays an important role in the optimization of reactive control. Importantly, these results further indicate that the advance preparation of action plans reduces the need for reactive fronto-basal ganglia communication to gate voluntary actions. PMID:22875921

  4. Technical integration of hippocampus, basal ganglia and physical models for spatial navigation

    Directory of Open Access Journals (Sweden)

    Charles W Fox

    2009-03-01

    Full Text Available Computational neuroscience is increasingly moving beyond modeling individual neurons or neural systems to consider the integration of multiple models, often constructed by different research groups. We report on our preliminary technical integration of recent hippocampal formation, basal ganglia and physical environment models, together with visualisation tools, as a case study in the use of Python across the modelling tool-chain. We do not present new modeling results here. The architecture incorporates leaky-integrator and rate-coded neurons, a 3D environment with collision detection and tactile sensors, 3D graphics and 2D plots. We found Python to be a flexible platform, offering a significant reduction in development time, without a corresponding significant increase in execution time. We illustrate this by implementing a part of the model in various alternative languages and coding styles, and comparing their execution times. For very large scale system integration, communication with other languages and parallel execution may be required, which we demonstrate using the BRAHMS framework's Python bindings.

  5. The Basal Ganglia Select the Expected Sensory Input Used for Predictive Coding

    Directory of Open Access Journals (Sweden)

    Brian eColder

    2015-09-01

    Full Text Available While considerable evidence supports the notion that lower-level interpretation of incoming sensory information is guided by top-down sensory expectations, less is known about the source of the sensory expectations or the mechanisms by which they are spread. Predictive coding theory proposes that sensory expectations flow down from higher-level association areas to lower-level sensory cortex, and deviations from those expectations (error signals flow back up to association areas. A separate theory of the role of prediction in cognition describes emulations as linked representations of potential actions and their associated expected sensation that are hypothesized to play an important role in many aspects of cognition. The expected sensations in active emulations are proposed to be the top-down expectation used in predictive coding. Representations of the potential action and expected sensation in emulations are thought to be instantiated in distributed cortical networks. Combining predictive coding with emulations thus provides a theoretical link between the top-down expectations that guide sensory expectations and the cortical networks representing potential actions. Now moving to theories of action selection, the basal ganglia has long been proposed to select between potential actions by reducing inhibition to the cortical network instantiating the desired action plan. Integration of these isolated theories

  6. Time-course of coherence in the human basal ganglia during voluntary movements

    Science.gov (United States)

    Talakoub, Omid; Neagu, Bogdan; Udupa, Kaviraja; Tsang, Eric; Chen, Robert; Popovic, Milos R.; Wong, Willy

    2016-01-01

    We are interested in characterizing how brain networks interact and communicate with each other during voluntary movements. We recorded electrical activities from the globus pallidus pars interna (GPi), subthalamic nucleus (STN) and the motor cortex during voluntary wrist movements. Seven patients with dystonia and six patients with Parkinson’s disease underwent bilateral deep brain stimulation (DBS) electrode placement. Local field potentials from the DBS electrodes and scalp EEG from the electrodes placed over the motor cortices were recorded while the patients performed externally triggered and self-initiated movements. The coherence calculated between the motor cortex and STN or GPi was found to be coupled to its power in both the beta and the gamma bands. The association of coherence with power suggests that a coupling in neural activity between the basal ganglia and the motor cortex is required for the execution of voluntary movements. Finally, we propose a mathematical model involving coupled neural oscillators which provides a possible explanation for how inter-regional coupling takes place. PMID:27725721

  7. Model-based action planning involves cortico-cerebellar and basal ganglia networks

    Science.gov (United States)

    Fermin, Alan S. R.; Yoshida, Takehiko; Yoshimoto, Junichiro; Ito, Makoto; Tanaka, Saori C.; Doya, Kenji

    2016-01-01

    Humans can select actions by learning, planning, or retrieving motor memories. Reinforcement Learning (RL) associates these processes with three major classes of strategies for action selection: exploratory RL learns state-action values by exploration, model-based RL uses internal models to simulate future states reached by hypothetical actions, and motor-memory RL selects past successful state-action mapping. In order to investigate the neural substrates that implement these strategies, we conducted a functional magnetic resonance imaging (fMRI) experiment while humans performed a sequential action selection task under conditions that promoted the use of a specific RL strategy. The ventromedial prefrontal cortex and ventral striatum increased activity in the exploratory condition; the dorsolateral prefrontal cortex, dorsomedial striatum, and lateral cerebellum in the model-based condition; and the supplementary motor area, putamen, and anterior cerebellum in the motor-memory condition. These findings suggest that a distinct prefrontal-basal ganglia and cerebellar network implements the model-based RL action selection strategy. PMID:27539554

  8. Changing pattern in the basal ganglia: motor switching under reduced dopaminergic drive.

    Science.gov (United States)

    Fiore, Vincenzo G; Rigoli, Francesco; Stenner, Max-Philipp; Zaehle, Tino; Hirth, Frank; Heinze, Hans-Jochen; Dolan, Raymond J

    2016-01-01

    Action selection in the basal ganglia is often described within the framework of a standard model, associating low dopaminergic drive with motor suppression. Whilst powerful, this model does not explain several clinical and experimental data, including varying therapeutic efficacy across movement disorders. We tested the predictions of this model in patients with Parkinson's disease, on and off subthalamic deep brain stimulation (DBS), focussing on adaptive sensory-motor responses to a changing environment and maintenance of an action until it is no longer suitable. Surprisingly, we observed prolonged perseverance under on-stimulation, and high inter-individual variability in terms of the motor selections performed when comparing the two conditions. To account for these data, we revised the standard model exploring its space of parameters and associated motor functions and found that, depending on effective connectivity between external and internal parts of the globus pallidus and saliency of the sensory input, a low dopaminergic drive can result in increased, dysfunctional, motor switching, besides motor suppression. This new framework provides insight into the biophysical mechanisms underlying DBS, allowing a description in terms of alteration of the signal-to-baseline ratio in the indirect pathway, which better account of known electrophysiological data in comparison with the standard model. PMID:27004463

  9. Disconnecting force from money: effects of basal ganglia damage on incentive motivation.

    Science.gov (United States)

    Schmidt, Liane; d'Arc, Baudouin Forgeot; Lafargue, Gilles; Galanaud, Damien; Czernecki, Virginie; Grabli, David; Schüpbach, Michael; Hartmann, Andreas; Lévy, Richard; Dubois, Bruno; Pessiglione, Mathias

    2008-05-01

    Bilateral basal ganglia lesions have been reported to induce a particular form of apathy, termed auto-activation deficit (AAD), principally defined as a loss of self-driven behaviour that is reversible with external stimulation. We hypothesized that AAD reflects a dysfunction of incentive motivation, a process that translates an expected reward (or goal) into behavioural activation. To investigate this hypothesis, we designed a behavioural paradigm contrasting an instructed (externally driven) task, in which subjects have to produce different levels of force by squeezing a hand grip, to an incentive (self-driven) task, in which subjects can win, depending on their hand grip force, different amounts of money. Skin conductance was simultaneously measured to index affective evaluation of monetary incentives. Thirteen AAD patients with bilateral striato-pallidal lesions were compared to thirteen unmedicated patients with Parkinson's; disease (PD), which is characterized by striatal dopamine depletion and regularly associated with apathy. AAD patients did not differ from PD patients in terms of grip force response to external instructions or skin conductance response to monetary incentives. However, unlike PD patients, they failed to distinguish between monetary incentives in their grip force. We conclude that bilateral striato-pallidal damage specifically disconnects motor output from affective evaluation of potential rewards. PMID:18344560

  10. Eyes on MEGDEL: distinctive basal ganglia involvement in dystonia deafness syndrome.

    Science.gov (United States)

    Wortmann, Saskia B; van Hasselt, Peter M; Barić, Ivo; Burlina, Alberto; Darin, Niklas; Hörster, Friederike; Coker, Mahmut; Ucar, Sema Kalkan; Krumina, Zita; Naess, Karin; Ngu, Lock H; Pronicka, Ewa; Riordan, Gilian; Santer, Rene; Wassmer, Evangeline; Zschocke, Johannes; Schiff, Manuel; de Meirleir, Linda; Alowain, Mohammed A; Smeitink, Jan A M; Morava, Eva; Kozicz, Tamas; Wevers, Ron A; Wolf, Nicole I; Willemsen, Michel A

    2015-04-01

    Pediatric movement disorders are still a diagnostic challenge, as many patients remain without a (genetic) diagnosis. Magnetic resonance imaging (MRI) pattern recognition can lead to the diagnosis. MEGDEL syndrome (3-MethylGlutaconic aciduria, Deafness, Encephalopathy, Leigh-like syndrome MIM #614739) is a clinically and biochemically highly distinctive dystonia deafness syndrome accompanied by 3-methylglutaconic aciduria, severe developmental delay, and progressive spasticity. Mutations are found in SERAC1, encoding a phosphatidylglycerol remodeling enzyme essential for both mitochondrial function and intracellular cholesterol trafficking. Based on the homogenous phenotype, we hypothesized an accordingly characteristic MRI pattern. A total of 43 complete MRI studies of 30 patients were systematically reevaluated. All patients presented a distinctive brain MRI pattern with five characteristic disease stages affecting the basal ganglia, especially the putamen. In stage 1, T2 signal changes of the pallidum are present. In stage 2, swelling of the putamen and caudate nucleus is seen. The dorsal putamen contains an "eye" that shows no signal alteration and (thus) seems to be spared during this stage of the disease. It later increases, reflecting progressive putaminal involvement. This "eye" was found in all patients with MEGDEL syndrome during a specific age range, and has not been reported in other disorders, making it pathognomonic for MEDGEL and allowing diagnosis based on MRI findings.

  11. Interaction between basal ganglia and limbic circuits in learning and memory processes.

    Science.gov (United States)

    Calabresi, Paolo; Picconi, Barbara; Tozzi, Alessandro; Ghiglieri, Veronica

    2016-01-01

    Hippocampus and striatum play distinctive roles in memory processes since declarative and non-declarative memory systems may act independently. However, hippocampus and striatum can also be engaged to function in parallel as part of a dynamic system to integrate previous experience and adjust behavioral responses. In these structures the formation, storage, and retrieval of memory require a synaptic mechanism that is able to integrate multiple signals and to translate them into persistent molecular traces at both the corticostriatal and hippocampal/limbic synapses. The best cellular candidate for this complex synthesis is represented by long-term potentiation (LTP). A common feature of LTP expressed in these two memory systems is the critical requirement of convergence and coincidence of glutamatergic and dopaminergic inputs to the dendritic spines of the neurons expressing this form of synaptic plasticity. In experimental models of Parkinson's disease abnormal accumulation of α-synuclein affects these two memory systems by altering two major synaptic mechanisms underlying cognitive functions in cholinergic striatal neurons, likely implicated in basal ganglia dependent operative memory, and in the CA1 hippocampal region, playing a central function in episodic/declarative memory processes.

  12. Making working memory work: a computational model of learning in the prefrontal cortex and basal ganglia.

    Science.gov (United States)

    O'Reilly, Randall C; Frank, Michael J

    2006-02-01

    The prefrontal cortex has long been thought to subserve both working memory (the holding of information online for processing) and executive functions (deciding how to manipulate working memory and perform processing). Although many computational models of working memory have been developed, the mechanistic basis of executive function remains elusive, often amounting to a homunculus. This article presents an attempt to deconstruct this homunculus through powerful learning mechanisms that allow a computational model of the prefrontal cortex to control both itself and other brain areas in a strategic, task-appropriate manner. These learning mechanisms are based on subcortical structures in the midbrain, basal ganglia, and amygdala, which together form an actor-critic architecture. The critic system learns which prefrontal representations are task relevant and trains the actor, which in turn provides a dynamic gating mechanism for controlling working memory updating. Computationally, the learning mechanism is designed to simultaneously solve the temporal and structural credit assignment problems. The model's performance compares favorably with standard backpropagation-based temporal learning mechanisms on the challenging 1-2-AX working memory task and other benchmark working memory tasks. PMID:16378516

  13. Role of beta-arrestin 2 downstream of dopamine receptors in the basal ganglia

    Directory of Open Access Journals (Sweden)

    Thomas eDel'Guidice

    2011-09-01

    Full Text Available Multifunctional scaffolding protein beta-arrestins (βArr and the G protein receptor kinases (GRK are involved in the desensitization of several G protein coupled-receptors (GPCR. However, arrestins can also contribute to GPCR signaling independently from G proteins. In this review, we focus on the role of βArr in the regulation of dopamine receptor functions in the striatum. First, we present in vivo evidence supporting a role for these proteins in the regulation of dopamine receptor desensitization. Second, we provide an overview of the roles of βArr-2 in the regulation of ERK/MAPkinases and Akt/GSK3 signaling pathways downstream of the D1 and D2 dopamine receptors. Thereafter, we examine the possible involvement of βArr-mediated signaling in the action of dopaminergic drugs used for the treatment of mental disorders. Finally, we focus on different potential cellular proteins regulated by βArr-mediated signaling which could contribute to the regulation of behavioral responses to dopamine. Overall, the identification of a cell signaling function for βArr downstream of dopamine receptors underscores the intricate complexity of the intertwined mechanisms regulating and mediating cell signaling in the basal ganglia. Understanding these mechanisms may lead to a better comprehension of the several roles played by these structures in the regulation of mood and to the development of new psychoactive drugs having better therapeutic efficacy.

  14. Unusual progression of herpes simplex encephalitis with basal ganglia and extensive white matter involvement

    Directory of Open Access Journals (Sweden)

    Yasuhiro Manabe

    2009-08-01

    Full Text Available We report a 51-year old male with herpes simplex encephalitis (HSE showing unusual progression and magnetic resonance (MR findings. The initial neurological manifestation of intractable focal seizure with low-grade fever persisted for three days, and rapidly coma, myoclonic status, and respiratory failure with high-grade fever emerged thereafter. The polymerase chain reaction (PCR result of cerebrospinal fluid (CSF was positive for HSV-1 DNA. In the early stage, MR images (MRI were normal. On subsequent MR diffusion-weighted (DW and fluid-attenuated inversion recovery (FLAIR images, high-intensity areas first appeared in the left frontal cortex, which was purely extra-temporal involvement, and extended into the basal ganglia, then the white matter, which are relatively spared in HSE. Antiviral therapy and immunosuppressive therapy did not suppress the progression of HSE, and finally severe cerebral edema developed into cerebral herniation, which required emergency decompressive craniectomy. Histological examination of a biopsy specimen of the white matter detected perivascular infiltration and destruction of basic structure, which confirmed non specific inflammatory change without obvious edema or demyelination. The present case shows both MR and pathological findings in the white matter in the acute stage of HSE.

  15. Model-based action planning involves cortico-cerebellar and basal ganglia networks.

    Science.gov (United States)

    Fermin, Alan S R; Yoshida, Takehiko; Yoshimoto, Junichiro; Ito, Makoto; Tanaka, Saori C; Doya, Kenji

    2016-01-01

    Humans can select actions by learning, planning, or retrieving motor memories. Reinforcement Learning (RL) associates these processes with three major classes of strategies for action selection: exploratory RL learns state-action values by exploration, model-based RL uses internal models to simulate future states reached by hypothetical actions, and motor-memory RL selects past successful state-action mapping. In order to investigate the neural substrates that implement these strategies, we conducted a functional magnetic resonance imaging (fMRI) experiment while humans performed a sequential action selection task under conditions that promoted the use of a specific RL strategy. The ventromedial prefrontal cortex and ventral striatum increased activity in the exploratory condition; the dorsolateral prefrontal cortex, dorsomedial striatum, and lateral cerebellum in the model-based condition; and the supplementary motor area, putamen, and anterior cerebellum in the motor-memory condition. These findings suggest that a distinct prefrontal-basal ganglia and cerebellar network implements the model-based RL action selection strategy. PMID:27539554

  16. Functional lateralization in cingulate cortex predicts motor recovery after basal ganglia stroke.

    Science.gov (United States)

    Li, Yao; Chen, Zengai; Su, Xin; Zhang, Xiaoliu; Wang, Ping; Zhu, Yajing; Xu, Qun; Xu, Jianrong; Tong, Shanbao

    2016-02-01

    The basal ganglia (BG) is involved in higher order motor control such as movement planning and execution of complex motor synergies. Neuroimaging study on stroke patients specifically with BG lesions would help to clarify the consequence of BG damage on motor control. In this paper, we performed a longitudinal study in the stroke patients with lesions in BG regions across three motor recovery stages, i.e., less than 2week (Session 1), 1-3m (Session 2) and more than 3m (Session 3). The patients showed an activation shift from bilateral hemispheres during early sessions (3m), suggesting a compensation effect from the contralesional hemisphere during motor recovery. We found that the lateralization of cerebellum(CB) for affected hand task correlated with patients' concurrent Fugl-Meyer index (FMI) in Session 2. Moreover, the cingulate cortex lateralization index in Session 2 was shown to significantly correlate with subsequent FMI change between Session 3 and Session 2, which serves as a prognostic marker for motor recovery. Our findings consolidated the close interactions between BG and CB during the motor recovery after stroke. The dominance of activation in contralateral cingulate cortex was associated with a better motor recovery, suggesting the important role of ipsilesional attention modulation in the early stage after BG stroke. PMID:26742641

  17. Subthalamic, not striatal, activity correlates with basal ganglia downstream activity in normal and parkinsonian monkeys

    Science.gov (United States)

    Deffains, Marc; Iskhakova, Liliya; Katabi, Shiran; Haber, Suzanne N; Israel, Zvi; Bergman, Hagai

    2016-01-01

    The striatum and the subthalamic nucleus (STN) constitute the input stage of the basal ganglia (BG) network and together innervate BG downstream structures using GABA and glutamate, respectively. Comparison of the neuronal activity in BG input and downstream structures reveals that subthalamic, not striatal, activity fluctuations correlate with modulations in the increase/decrease discharge balance of BG downstream neurons during temporal discounting classical condition task. After induction of parkinsonism with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), abnormal low beta (8-15 Hz) spiking and local field potential (LFP) oscillations resonate across the BG network. Nevertheless, LFP beta oscillations entrain spiking activity of STN, striatal cholinergic interneurons and BG downstream structures, but do not entrain spiking activity of striatal projection neurons. Our results highlight the pivotal role of STN divergent projections in BG physiology and pathophysiology and may explain why STN is such an effective site for invasive treatment of advanced Parkinson's disease and other BG-related disorders. DOI: http://dx.doi.org/10.7554/eLife.16443.001 PMID:27552049

  18. Idiopathic basal ganglia calcification-associated PDGFRB mutations impair the receptor signalling

    Science.gov (United States)

    Arts, Florence A; Velghe, Amélie I; Stevens, Monique; Renauld, Jean-Christophe; Essaghir, Ahmed; Demoulin, Jean-Baptiste

    2015-01-01

    Platelet-derived growth factors (PDGF) bind to two related receptor tyrosine kinases, which are encoded by the PDGFRA and PDGFRB genes. Recently, heterozygous PDGFRB mutations have been described in patients diagnosed with idiopathic basal ganglia calcification (IBGC or Fahr disease), a rare inherited neurological disorder. The goal of the present study was to determine whether these mutations had a positive or negative impact on the PDGFRB activity. We first showed that the E1071V mutant behaved like wild-type PDGFRB and may represent a polymorphism unrelated to IBGC. In contrast, the L658P mutant had no kinase activity and failed to activate any of the pathways normally stimulated by PDGF. The R987W mutant activated Akt and MAP kinases but did not induce the phosphorylation of signal transducer and activator of transcription 3 (STAT3) after PDGF stimulation. Phosphorylation of phospholipase Cγ was also decreased. Finally, we showed that the R987W mutant was more rapidly degraded upon PDGF binding compared to wild-type PDGFRB. In conclusion, PDGFRB mutations associated with IBGC impair the receptor signalling. PDGFRB loss of function in IBGC is consistent with recently described inactivating mutations in the PDGF-B ligand. These results raise concerns about the long-term safety of PDGF receptor inhibition by drugs such as imatinib. PMID:25292412

  19. Functional Roles of the Thalamus for Language Capacities

    Directory of Open Access Journals (Sweden)

    Fabian eKlostermann

    2013-07-01

    Full Text Available Early biological concepts of language were predominantly corticocentric, but over the last decades biolinguistic research, equipped with new technical possibilities, has drastically changed this view. To date, connectionist models, conceiving linguistic skills as corticobasal network activities, dominate our understanding of the neural basis of language. However, beyond the notion of an involvement of the thalamus and, in most cases also, the basal ganglia in linguistic operations, specific functions of the respective depth structures mostly remain rather controversial. In this review, some of these issues shall be discussed, particularly the functional configuration of basal network components and the language specificity of subcortical supporting activity. Arguments will be provided for a primarily cortico-thalamic language network. In this view, the thalamus does not engage in proper linguistic operations, but rather acts as a central monitor for language-specific cortical activities, supported by the basal ganglia in both perceptual and productive language execution.

  20. Late-Onset Mania in a Patient with Movement Disorder and Basal Ganglia Calcifications: A Challenge for Diagnosis and Treatment

    Science.gov (United States)

    Roiter, Beatrice; Pigato, Giorgio; Perugi, Giulio

    2016-01-01

    Age of onset can have a significant impact on clinical course and pathophysiological mechanism of bipolar disorder. Late-onset bipolar episodes are more likely linked to medical illnesses and so are frequently classified as “secondary” forms of mood disorder. We discuss the case of a patient who at the age of 58 presented his first delusional-manic episode. He also had mild frontal and occipital cortical atrophy, white matter posterior ischemic lesions, and small basal ganglia calcifications. Seven years later, he presented a second manic episode with new emergent hyperkinetic choreiform symptoms. Taking into account movement disturbances, the presence of basal ganglia calcification, and worsening of cortical atrophy, we performed a differential diagnosis between Fahr disease, Fahr's syndrome, calcifications due to ageing, supersensitivity psychosis, and dementia. Valproate, quetiapine, and tetrabenazine were sequentially administered and yielded a good therapeutic response as regards manic and movement symptoms. Relationship between medications and course of specific symptoms was observed. PMID:27213069

  1. The arbitration-extension hypothesis: a hierarchical interpretation of the functional organization of the basal ganglia

    Directory of Open Access Journals (Sweden)

    Iman eKamali Sarvestani

    2011-03-01

    Full Text Available Based on known anatomy and physiology, we present a hypothesis where the basal gangliamotor loop is hierarchically organized in two main subsystems: the arbitration system andthe extension system. The arbitration system, comprised of the subthalamic nucleus, globuspallidus, and pedunculopontine nucleus, serves the role of selecting one out of several candidateactions as they are ascending from various brain stem motor regions and aggregated in thecentromedian thalamus or descending from the extension system or from the cerebral cortex.This system is an action-input/action-output system whose winner-take-all mechanism findsthe strongest response among several candidates to execute. This decision is communicatedback to the brain stem by facilitating the desired action via cholinergic/glutamatergic projectionsand suppressing conflicting alternatives via GABAergic connections. The extension system,comprised of the striatum and, again, globus pallidus, can extend the repertoire of responsesby learning to associate novel complex states to certain actions. This system is a state-input/action-output system, whose organization enables it to encode arbitrarily complex Booleanlogic rules using striatal neurons that only fire given specific constellations of inputs (BooleanAND and pallidal neurons that are silenced by any striatal input (Boolean OR. We demonstratethe capabilities of this hierarchical system by a computational model where a simulatedgeneric animal interacts with an environment by selecting direction of movement basedon combinations of sensory stimuli, some being appetitive, others aversive or neutral. Whilethe arbitration system can autonomously handle conflicting actions proposed by brain stemmotor nuclei, the extension system is required to execute learned actions not suggested byexternal motor centers. Being precise in the functional role of each component of the system,this hypothesis generates several readily testable predictions.

  2. Tailored keyhole surgery for basal ganglia cavernous malformation with preoperative three-dimensional pyramidal tracts assessment and intraoperative electrophysiological monitoring

    Institute of Scientific and Technical Information of China (English)

    Kai Quan; Geng Xu; Fan Zhao; Wei Zhu

    2016-01-01

    Background:Accurately mapping the pyramidal tracts preoperatively and intraoperatively is the primary concern when operating on cavernous malformations (CMS) in the basal ganglia.We have conducted new methods for preoperative planning and have tailored lesion resection to prevent the damage of pyramidal tracts.Patients and methods:Eleven patients harboring cavernous malformations in basal ganglia were treated surgically from April 2008 to January 2015.Surgical planning was based on three-dimensional diffusion tensor pyramidal tractography and Virtual Reality system.Intraoperative detecting of pyramidal tracts with subcortical stimulation mapping and motor evoked potential monitoring were performed.The extent of resection and postoperative neurological function were assessed in each case.Results:Total removal of the cavernous malformations were achieved in each case.Four of the total eleven cases presented temporary neurological deficits,including one occurrence of hemiparesis and three occurrences of hemianesthesia.No permanent neurological deficit was developed in this series of cases.Conclusion:Three-dimensional diffusion tensor pyramidal tractography is quite helpful for preoperative planning of basal ganglia cavernous malformations,especially in choosing a suitable surgical approach.Intraoperative detection of pyramidal tracts with subcortical stimulation mapping and motor evoked potential monitoring play important roles in preventing damage to pyramidal tracts during lesion resection.

  3. Familial idiopathic basal ganglia calcification: Histopathologic features of an autopsied patient with an SLC20A2 mutation.

    Science.gov (United States)

    Kimura, Tadashi; Miura, Takeshi; Aoki, Kenju; Saito, Shoji; Hondo, Hiroaki; Konno, Takuya; Uchiyama, Akio; Ikeuchi, Takeshi; Takahashi, Hitoshi; Kakita, Akiyoshi

    2016-08-01

    Idiopathic basal ganglia calcification (IBGC), or Fahr's disease, is a neurological disorder characterized by widespread calcification in the brain. Recently, several causative genes have been identified, but the histopathologic features of the brain lesions and expression of the gene products remain unclear. Here, we report the clinical and autopsy features of a 62-year-old Japanese man with familial IBGC, in whom an SLC20A2 mutation was identified. The patient developed mild cognitive impairment and parkinsonism. A brain CT scan demonstrated abnormal calcification in the bilateral basal ganglia, thalami and cerebellum. An MRI study at this point revealed glioblastoma, and the patient died 6 months later. At autopsy, symmetric calcification in the basal ganglia, thalami, cerebellar white matter and deeper layers of the cerebral cortex was evident. The calcification was observed in the tunica media of small arteries, arterioles and capillaries, but not in veins. Immunohistochemistry using an antibody against type III sodium-dependent phosphate transporter 2 (PiT-2), the SLC20A2 product, demonstrated that astrocytic processes were labeled in several regions in control brains, whereas in the patient, reactivity in astrocytes was apparently weak. Immunoblotting demonstrated a marked decrease of PiT-2 in the patient. There are few autopsy reports of IBGC patients with confirmation of the genetic background. The autopsy features seem informative for better understanding the histogenesis of IBGC lesions. PMID:26635128

  4. A movable microelectrode array for chronic basal ganglia single-unit electrocorticogram co-recording in freely behaving rats.

    Science.gov (United States)

    Zheng, Xiaobin; Zeng, Jia; Chen, Ting; Lin, Yuanxiang; Yu, Lianghong; Li, Ying; Lin, Zhangya; Wu, Xiyue; Chen, Fuyong; Kang, Dezhi; Zhang, Shizhong

    2014-09-01

    The basal ganglia-cortical circuits are important for information process to brain function. However, chronic recording of single-unit activities in the basal ganglia nucleus has not yet been well established. We present a movable bundled microwire array for chronic subthalamic nucleus (STN) single-unit electrocorticogram co-recording. The electrode assembly contains a screw-advanced microdrive and a microwire array. The array consists of a steel guide tube, five recording wires and one referenced wire which form the shape of a guiding hand, and one screw electrode for cortico-recording. The electrode can acquire stable cortex oscillation-driven STN firing units in rats under different behaving conditions for 8 weeks. We achieved satisfying signal-to-noise ratio, portions of cells retaining viability, and spike waveform similarities across the recording sections. Using this method, we investigated neural correlations of the basal ganglia-cortical circuits in different behaving conditions. This method will become a powerful tool for multi-region recording to study normal statements or movement disorders.

  5. Recovery of language function in Korean-Japanese crossed bilingual aphasia following right basal ganglia hemorrhage.

    Science.gov (United States)

    Lee, Boram; Moon, Hyun Im; Lim, Sung Hee; Cho, Hyesuk; Choi, Hyunjoo; Pyun, Sung-Bom

    2016-06-01

    Few studies have investigated language recovery patterns and the mechanisms of crossed bilingual aphasia following a subcortical stroke. In particular, Korean-Japanese crossed bilingual aphasia has not been reported. A 47-year-old, right-handed man was diagnosed with an extensive right basal ganglia hemorrhage. He was bilingual, fluent in both Korean and Japanese. After his stroke, the patient presented with crossed aphasia. We investigated changes in the Korean (L1) and Japanese (L2) language recovery patterns. Both Korean and Japanese versions of the Western Aphasia Battery (WAB) were completed one month after the stroke, and functional magnetic resonance imaging (fMRI) was performed using picture-naming tasks. The WAB showed a paradoxical pattern of bilingual aphasia, with an aphasia quotient (AQ) of 32 for Korean and 50.6 for Japanese, with Broca's aphasia. The patient scored better in the Japanese version of all domains of the tests. The fMRI study showed left lateralized activation in both language tasks, especially in the inferior frontal gyrus. After six months of language therapy targeting L1, the Korean-WAB score improved significantly, while the Japanese-WAB score showed slight improvement. In this case, the subcortical lesion contributed to crossed bilingual aphasia more highly affecting L1 due to loss of the cortico-subcortical control mechanism in the dominant hemisphere. The paradoxical pattern of bilingual aphasia disappeared after lengthy language therapy targeting L1, and the therapy effect did not transfer to L2. Language recovery in L1 might have been accomplished by reintegrating language networks, including the contralesional language homologue area in the left hemisphere.

  6. Neurobrucellosis with transient ischemic attack, vasculopathic changes, intracerebral granulomas and basal ganglia infarction: a case report

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    Ozyurek Seyfi C

    2010-10-01

    Full Text Available Abstract Introduction Central nervous system involvement is a rare but serious manifestation of brucellosis. We present an unusual case of neurobrucellosis with transient ischemic attack, intracerebral vasculopathy granulomas, seizures, and paralysis of sixth and seventh cranial nerves. Case presentation A 17-year-old Caucasian man presented with nausea and vomiting, headache, double vision and he gave a history of weakness in the left arm, speech disturbance and imbalance. Physical examination revealed fever, doubtful neck stiffness and left abducens nerve paralysis. An analysis of his cerebrospinal fluid showed a pleocytosis (lymphocytes, 90%, high protein and low glucose levels. He developed generalized tonic-clonic seizures, facial paralysis and left hemiparesis. Cranial magnetic resonance imaging demonstrated intracerebral vasculitis, basal ganglia infarction and granulomas, mimicking the central nervous system involvement of tuberculosis. On the 31st day of his admission, neurobrucellosis was diagnosed with immunoglobulin M and immunoglobulin G positivity by standard tube agglutination test and enzyme-linked immunosorbent assay in both serum and cerebrospinal fluid samples (the tests had been negative until that day. He was treated successfully with trimethoprim and sulfamethoxazole, doxycyline and rifampicin for six months. Conclusions Our patient illustrates the importance of suspecting brucellosis as a cause of meningoencephalitis, even if cultures and serological tests are negative at the beginning of the disease. As a result, in patients who have a history of residence or travel to endemic areas, neurobrucellosis should be considered in the differential diagnosis of any neurologic symptoms. If initial tests fail, repetition of these tests at appropriate intervals along with complementary investigations are indicated.

  7. A spiking Basal Ganglia model of synchrony, exploration and decision making

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    Alekhya eMandali

    2015-05-01

    Full Text Available To make an optimal decision we need to weigh all the available options, compare them with the current goal, and choose the most rewarding one. Depending on the situation an optimal decision could be to either ‘explore’ or ‘exploit’ or ‘not to take any action’ for which the Basal Ganglia (BG is considered to be a key neural substrate. In an attempt to expand this classical picture of BG function, we had earlier hypothesized that the Indirect Pathway (IP of the BG could be the subcortical substrate for exploration. In this study we build a spiking network model to relate exploration to synchrony levels in the BG (which are a neural marker for tremor in Parkinson’s disease. Key BG nuclei such as the Sub Thalamic Nucleus (STN, Globus Pallidus externus (GPe and Globus Pallidus internus (GPi were modeled as Izhikevich spiking neurons whereas the Striatal output was modeled as Poisson spikes. The model is cast in reinforcement learning framework with the dopamine signal representing reward prediction error. We apply the model to two decision making tasks: a binary action selection task (similar to one used by Humphries et al. 2006 and an n-armed bandit task (Bourdaud et al. 2008. The model shows that exploration levels could be controlled by STN’s lateral connection strength which also influenced the synchrony levels in the STN-GPe circuit. An increase in STN’s lateral strength led to a decrease in exploration which can be thought as the possible explanation for reduced exploratory levels in Parkinson’s patients. Our simulations also show that on complete removal of IP, the model exhibits only Go and No-Go behaviors, thereby demonstrating the crucial role of IP in exploration. Our model provides a unified account for synchronization, action section, and explorative behavior.

  8. The Effects of Cues on Neurons in the Basal Ganglia in Parkinson’s Disease

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    Sridevi V. Sarma

    2012-07-01

    Full Text Available Visual cues open a unique window to the understanding of Parkinson’s disease (PD. These cues can temporarily but dramatically improve PD motor symptoms. Although details are unclear, cues are believed to suppress pathological basal ganglia (BG activity through activation of corticostriatal pathways. In this study, we investigated human BG neurophysiology under different cued conditions. We evaluated bursting, 10-30Hz oscillations (OSCs, and directional tuning (DT dynamics in the subthalamic nucleus activity while 7 patients executed a two-step motor task. In the first step (predicted +cue, the patient moved to a target when prompted by a visual go cue that appeared 100% of the time. Here, the timing of the cue is predictable and the cue serves an external trigger to execute a motor plan. In the second step, the cue appeared randomly 50% of the time, and the patient had to move to the same target as in the first step. When it appeared (unpredicted +cue, the motor plan was to be triggered by the cue, but its timing was not predictable. When the cue failed to appear (unpredicted -cue, the motor plan was triggered by the absence of the visual cue. We found that during predicted +cue and unpredicted -cue trials, OSCs significantly decreased and DT significantly increased above baseline, though these modulations occurred an average of 640 milliseconds later in unpredicted -cue trials. Movement and reaction times were comparable in these trials. During unpredicted +cue trials, OSCs and DT failed to modulate though bursting significantly decreased after movement. Correspondingly, movement performance deteriorated. These findings suggest that during motor planning either a predictably timed external cue or an internally generated cue (generated by the absence of a cue trigger the execution of a motor plan in premotor cortex, whose increased activation then suppresses pathological activity in STN through direct pathways, leading to motor facilitation in

  9. Functional Relevance of Different Basal Ganglia Pathways Investigated in a Spiking Model with Reward Dependent Plasticity.

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    Berthet, Pierre; Lindahl, Mikael; Tully, Philip J; Hellgren-Kotaleski, Jeanette; Lansner, Anders

    2016-01-01

    The brain enables animals to behaviorally adapt in order to survive in a complex and dynamic environment, but how reward-oriented behaviors are achieved and computed by its underlying neural circuitry is an open question. To address this concern, we have developed a spiking model of the basal ganglia (BG) that learns to dis-inhibit the action leading to a reward despite ongoing changes in the reward schedule. The architecture of the network features the two pathways commonly described in BG, the direct (denoted D1) and the indirect (denoted D2) pathway, as well as a loop involving striatum and the dopaminergic system. The activity of these dopaminergic neurons conveys the reward prediction error (RPE), which determines the magnitude of synaptic plasticity within the different pathways. All plastic connections implement a versatile four-factor learning rule derived from Bayesian inference that depends upon pre- and post-synaptic activity, receptor type, and dopamine level. Synaptic weight updates occur in the D1 or D2 pathways depending on the sign of the RPE, and an efference copy informs upstream nuclei about the action selected. We demonstrate successful performance of the system in a multiple-choice learning task with a transiently changing reward schedule. We simulate lesioning of the various pathways and show that a condition without the D2 pathway fares worse than one without D1. Additionally, we simulate the degeneration observed in Parkinson's disease (PD) by decreasing the number of dopaminergic neurons during learning. The results suggest that the D1 pathway impairment in PD might have been overlooked. Furthermore, an analysis of the alterations in the synaptic weights shows that using the absolute reward value instead of the RPE leads to a larger change in D1. PMID:27493625

  10. Clinical characteristics and prognosis of traumatic basal ganglia hematomas: A retrospective analysis of 40 cases

    Institute of Scientific and Technical Information of China (English)

    Jialiang Li; Chunjiang Yu

    2006-01-01

    AIM: To retrospectively analyze the pathogenesis, clinical characteristics, treatment and prognostic characteristics in patients with traumatic basal ganglia hematomas (TBGH).METHODS: A retrospective analysis of the clinical data was performed in 40 patients with TBGH who were selected from 1 250 patients with closed brain injury, who admitted to the Department of Neurosurgery of Shangqiu First People's Hospital from January 1990 to January 2004. The pathogenesis, clinical characteristics and signs, results of radiological examination, treatment and prognostic characteristics were analyzed. The patients all had definite history of brain injury, manifested by neurological functional disturbance to different extent after brain injury, and basal ganglia hemorrhage was identified by CT after brain injury, and hemorrhagic volume were more than or equal to 2 mL. Totally 34 males and 6 females were enrolled, aged 16-72 years and 28 cases of them were younger than 40 years old. The prognosis of the patients was evaluated with Glasgow outcome scale (GOS) at 6 months after injury, and GOS scoring standard was 1-5 points (1 for dead; 2 for vegetative survival, long-term coma, manifestations of decorticate rigidity or decerebrate rigidity; 3 for severely disabled, should be look after by others; 4 for moderately disabled, be able in self-care; 5 for good recovery, adults can work and study).RESULTS: The enrolled cases accounted for 3.20% of the 1250 patients with closed brain injury admitted at the same period. ① The causes of injury included traffic accident in 36 cases, fall in 2 cases, and assault in 2 cases. ② At admission, the Glasgow coma scale (GCS) scores were as follow: 13-15 scores (mild) in 10 cases,9-12 scores (moderate)in 20 cases, and 3-8 scores (severe) in 10 cases. Hemiplegia presented in 37 cases,aphasia in 20 cases, conscious disturbance in 10 cases, unilateral mydriasis in 6 cases, and decerebrate rigidity in 2 cases. ③ TBGH was detected by CT within

  11. [Gait disturbances related to dysfunction of the cerebral cortex and basal ganglia].

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    Takezawa, Nobuo; Mizuno, Toshiki; Seo, Kazuya; Kondo, Masaki; Nakagawa, Masanori

    2010-11-01

    This review aimed to characterize the gait disturbances in Parkinson disease (PD) and highlight how a rehabilitation program would affect the care of patients with PD. The typical PD gait is a type of hypokinetic gait characterized by reduced stride length and velocity; shortening of the swing phase; and increase in the stance phase, double-limb support duration, and cadence rate. In the advanced phase of PD, start hesitation, shuffling and festinating gait, propulsion, and freezing of gait (FOG) become remarkable. Notably, in PD, attention may influence gait control, and sensory cueing may improve the stride length. Our study on gait impairment in PD by using a three-dimensional motion analysis system revealed that the stride length and walking speed decreased, but there was no change in cadence. The decreased stride length was due to reduction in the range of movement at the leg and pelvic joints. A 4-week physical rehabilitation program for PD improved the stride length and walking speed;this was achieved by increasing the range of movement of at the leg and pelvic joints. We also assessed the effects of a rehabilitation program for patients with PD who experienced FOG. Although the lower limb function was more impaired in patients with PD and FOG than in those with PD without FOG, the rehabilitation program was effective even for patients with PD and FOG. FOG might be associated with functional impairment of the lower limb as well as dysfunction of the fronto-basal ganglia circuit. We also reported 3 cases of camptocormia (bent spine syndrome) with autonomic dysfunction and rapid eye movement (REM) sleep behavior disorders (RBD) and compared their symptoms with those reported elsewhere. We think that the pedunculopontine nuclear area may control the postural muscle tone and locomotion in PD. On the basis of the results of our rehabilitation programs, we speculate that physical modalities may modify synaptic plasticity by utilizing the cerebellar and/or afferent

  12. Methylphenidate exposure induces dopamine neuron loss and activation of microglia in the basal ganglia of mice.

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    Shankar Sadasivan

    Full Text Available BACKGROUND: Methylphenidate (MPH is a psychostimulant that exerts its pharmacological effects via preferential blockade of the dopamine transporter (DAT and the norepinephrine transporter (NET, resulting in increased monoamine levels in the synapse. Clinically, methylphenidate is prescribed for the symptomatic treatment of ADHD and narcolepsy; although lately, there has been an increased incidence of its use in individuals not meeting the criteria for these disorders. MPH has also been misused as a "cognitive enhancer" and as an alternative to other psychostimulants. Here, we investigate whether chronic or acute administration of MPH in mice at either 1 mg/kg or 10 mg/kg, affects cell number and gene expression in the basal ganglia. METHODOLOGY/PRINCIPAL FINDINGS: Through the use of stereological counting methods, we observed a significant reduction (∼20% in dopamine neuron numbers in the substantia nigra pars compacta (SNpc following chronic administration of 10 mg/kg MPH. This dosage of MPH also induced a significant increase in the number of activated microglia in the SNpc. Additionally, exposure to either 1 mg/kg or 10 mg/kg MPH increased the sensitivity of SNpc dopaminergic neurons to the parkinsonian agent 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP. Unbiased gene screening employing Affymetrix GeneChip® HT MG-430 PM revealed changes in 115 and 54 genes in the substantia nigra (SN of mice exposed to 1 mg/kg and 10 mg/kg MPH doses, respectively. Decreases in the mRNA levels of gdnf, dat1, vmat2, and th in the substantia nigra (SN were observed with both acute and chronic dosing of 10 mg/kg MPH. We also found an increase in mRNA levels of the pro-inflammatory genes il-6 and tnf-α in the striatum, although these were seen only at an acute dose of 10 mg/kg and not following chronic dosing. CONCLUSION: Collectively, our results suggest that chronic MPH usage in mice at doses spanning the therapeutic range in humans, especially at

  13. Whole exome sequencing reveals compound heterozygous mutations in SLC19A3 causing biotin-thiamine responsive basal ganglia disease

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    L.J. Sremba

    2014-01-01

    Full Text Available Biotin-thiamine responsive basal ganglia disease (BTBGD is a rare metabolic condition caused by mutations in the SLC19A3 gene. BTBGD presents with encephalopathy and significant disease progression when not treated with biotin and/or thiamine. We present a patient of Mexican and European ancestry diagnosed with BTBGD found to have compound heterozygous frameshift mutations, one novel. Our report adds to the genotype-phenotype correlation, highlighting the clinical importance of considering SLC19A3 gene defects as part of the differential diagnosis for Leigh syndrome.

  14. Involvement of dopamine loss in extrastriatal basal ganglia nuclei in the pathophysiology of Parkinson’s disease

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    Abdelhamid eBenazzouz

    2014-05-01

    Full Text Available Parkinson’s disease is a neurological disorder characterized by the manifestation of motor symptoms, such as akinesia, muscle rigidity and tremor at rest. These symptoms are classically attributed to the degeneration of dopamine neurons in the pars compacta of substantia nigra (SNc, which results in a marked dopamine depletion in the striatum. It is well established that dopamine neurons in the SNc innervate not only the striatum, which is the main target, but also other basal ganglia nuclei including the two segments of globus pallidus and the subthalamic nucleus. The role of dopamine and its depletion in the striatum is well known, however, the role of dopamine depletion in the pallidal complex and the subthalamic nucleus in the genesis of their abnormal neuronal activity and in parkinsonian motor deficits is still not clearly determined. Based on recent experimental data from animal models of Parkinson's disease in rodents and non-human primates and also from parkinsonian patients, this review summarizes current knowledge on the role of dopamine in the modulation of basal ganglia neuronal activity and also the role of dopamine depletion in these nuclei in the pathophysiology of Parkinson's disease.

  15. Chromosome 10p deletion in a patient with hypoparathyroidism, severe mental retardation, autism and basal ganglia calcifications.

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    Verri, Annapia; Maraschio, Paola; Devriendt, Koen; Uggetti, Carla; Spadoni, Emanuela; Haeusler, Edward; Federico, Antonio

    2004-01-01

    Chromosome 10p terminal deletions have been associated with a DiGeorge like phenotype. Haploinsufficiency of the region 10p14-pter, results in hypoparathyroidism, sensorineural deafness, renal anomaly, that is the triad that features the HDR syndrome. Van Esch (2000) identified in a HDR patient, within a 200 kb critical region, the GATA3 gene, a transcription factor involved in the embryonic development of the parathyroids, auditory system and kidneys. We describe a new male patient, 33-year-old, with 10p partial deletion affected by hypocalcemia, basal ganglia calcifications and a severe autistic syndrome associated with mental retardation. Neurologically he presented severe impairment of language, hypotonia, clumsiness and a postural dystonic attitude. A peripheral involvement of auditory pathways was documented by auditory evoked potentials alterations. CT scan documented basal ganglia calcifications. Hyperintensity of the lentiform nuclei was evident at the MRI examination. Renal ultrasound scan was normal. Haploinsufficiency for GATA3 gene was documented with FISH analysis using cosmid clone 1.2. Phenotypic spectrum observed in del (10p) is more severe than the classical DGS spectrum. GATA3 has been found to regulate the development of serotoninergic neurons. A serotoninergic dysfunction may be linked with autism in this patient. PMID:15337474

  16. Incomplete and inaccurate vocal imitation after knockdown of FoxP2 in songbird basal ganglia nucleus Area X.

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    Sebastian Haesler

    2007-12-01

    Full Text Available The gene encoding the forkhead box transcription factor, FOXP2, is essential for developing the full articulatory power of human language. Mutations of FOXP2 cause developmental verbal dyspraxia (DVD, a speech and language disorder that compromises the fluent production of words and the correct use and comprehension of grammar. FOXP2 patients have structural and functional abnormalities in the striatum of the basal ganglia, which also express high levels of FOXP2. Since human speech and learned vocalizations in songbirds bear behavioral and neural parallels, songbirds provide a genuine model for investigating the basic principles of speech and its pathologies. In zebra finch Area X, a basal ganglia structure necessary for song learning, FoxP2 expression increases during the time when song learning occurs. Here, we used lentivirus-mediated RNA interference (RNAi to reduce FoxP2 levels in Area X during song development. Knockdown of FoxP2 resulted in an incomplete and inaccurate imitation of tutor song. Inaccurate vocal imitation was already evident early during song ontogeny and persisted into adulthood. The acoustic structure and the duration of adult song syllables were abnormally variable, similar to word production in children with DVD. Our findings provide the first example of a functional gene analysis in songbirds and suggest that normal auditory-guided vocal motor learning requires FoxP2.

  17. Acupuncture inhibits Notch1 and Hes1 protein expression in the basal ganglia of rats with cerebral hemorrhage

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    Wei Zou

    2015-01-01

    Full Text Available Notch pathway activation maintains neural stem cells in a proliferating state and increases nerve repair capacity. To date, studies have rarely focused on changes or damage to signal transduction pathways during cerebral hemorrhage. Here, we examined the effect of acupuncture in a rat model of cerebral hemorrhage. We examined four groups: in the control group, rats received no treatment. In the model group, cerebral hemorrhage models were established by infusing non-heparinized blood into the brain. In the acupuncture group, modeled rats had Baihui (DU20 and Qubin (GB7 acupoints treated once a day for 30 minutes. In the DAPT group, modeled rats had 0.15 μg/mL DAPT solution (10 mL infused into the brain. Immunohistochemistry and western blot results showed that acupuncture effectively inhibits Notch1 and Hes1 protein expression in rat basal ganglia. These inhibitory effects were identical to DAPT, a Notch signaling pathway inhibitor. Our results suggest that acupuncture has a neuroprotective effect on cerebral hemorrhage by inhibiting Notch-Hes signaling pathway transduction in rat basal ganglia after cerebral hemorrhage.

  18. Late-Onset Mania in a Patient with Movement Disorder and Basal Ganglia Calcifications: A Challenge for Diagnosis and Treatment

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    Beatrice Roiter

    2016-01-01

    Full Text Available Age of onset can have a significant impact on clinical course and pathophysiological mechanism of bipolar disorder. Late-onset bipolar episodes are more likely linked to medical illnesses and so are frequently classified as “secondary” forms of mood disorder. We discuss the case of a patient who at the age of 58 presented his first delusional-manic episode. He also had mild frontal and occipital cortical atrophy, white matter posterior ischemic lesions, and small basal ganglia calcifications. Seven years later, he presented a second manic episode with new emergent hyperkinetic choreiform symptoms. Taking into account movement disturbances, the presence of basal ganglia calcification, and worsening of cortical atrophy, we performed a differential diagnosis between Fahr disease, Fahr’s syndrome, calcifications due to ageing, supersensitivity psychosis, and dementia. Valproate, quetiapine, and tetrabenazine were sequentially administered and yielded a good therapeutic response as regards manic and movement symptoms. Relationship between medications and course of specific symptoms was observed.

  19. Dopamine transporter density in the basal ganglia assessed with [{sup 123}I]IPT SPET in children with attention deficit hyperactivity disorder

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    Cheon, Keun-Ah; Kim, Young-Kee; Namkoong, Kee; Kim, Chan-Hyung [Department of Psychiatry, College of Medicine, Yonsei University, Seoul (Korea); Ryu, Young Hoon; Lee, Jong Doo [Division of Nuclear Medicine, Department of Radiology, College of Medicine, Yonsei University, 146-92 Dogokdong, Gangnam-Gu, Seoul, 135-720 (Korea)

    2003-02-01

    Attention deficit hyperactivity disorder (ADHD) is a psychiatric disorder in childhood that is known to be associated with dopamine dysregulation. In this study, we investigated dopamine transporter (DAT) density in children with ADHD using iodine-123 labelled N-(3-iodopropen-2-yl)-2β-carbomethoxy-3β-(4-chlorophenyl) tropane ([{sup 123}I]IPT) single-photon emission tomography (SPET) and postulated that an alteration in DAT density in the basal ganglia is responsible for dopaminergic dysfunction in children with ADHD. Nine drug-naive children with ADHD and six normal children were included in the study. We performed brain SPET 2 h after the intravenous administration of [{sup 123}I]IPT and carried out both quantitative and qualitative analyses using the obtained SPET data, which were reconstructed for the assessment of the specific/non-specific DAT binding ratio in the basal ganglia. We then investigated the correlation between the severity scores of ADHD symptoms in children with ADHD assessed with ADHD rating scale-IV and the specific/non-specific DAT binding ratio in the basal ganglia. Drug-naive children with ADHD showed a significantly increased specific/non-specific DAT binding ratio in the basal ganglia compared with normal children. However, no significant correlation was found between the severity scores of ADHD symptoms in children with ADHD and the specific/non-specific DAT binding ratio in the basal ganglia. Our findings support the complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD. (orig.)

  20. Methyl CpG-binding protein 2 participating in the regulation of differentiation plasticity of nerve regeneration in the basal ganglia after ischemic stroke

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    LI Pan

    2013-11-01

    Full Text Available Background It is accepted that cerebral ischemia induces neurogenesis and neural stem cells (NSCs differentiation in non-neurogenic regions (especially in the basal ganglia. However, the mechanisms possibly involved in modulating the differentiation plasticity of NSCs are still let to known. This study aims to investigate the possible epigenetic mechanisms involved in the differentiation process of NSCs after ischemic stroke. Methods Western blotting analysis was used to detect the protein levels of methyl CpG-binding protien 2 (MeCP2 and phosphorylated MeCP2 (pMeCP2 in the ischemic basal ganglia of rat model at 3 d following middle cerebral artery occlusion (MCAO. Immunohistochemical staining was performed to observe the cellular distribution of MeCP2 and pMeCP2, the cellular colocalization of pMeCP2 with NSCs marker nestin and neuronal marker microtubule?associated protein 2 (MAP-2 in the ischemic basal ganglia of rat brains. Results 1 MeCP2 was phosphorylated in the basal ganglia after ischemic stroke, forming pMeCP2. MeCP2 positive cell number was decreased in the ischemic basal ganglia (t = 12.239, P = 0.000, while pMeCP2 positive cell number was increased in the ischemic basal ganglia (t = 5.808, P = 0.000. 2 Ischemic stroke induced a reduction of MeCP2 levels in the nucleus (t = 14.949, P = 0.000 and an elevation of pMeCP2 levels in the cytoplasm (t = 5.026, P = 0.001. 3 MeCP2 phosphorylation mediated the translocation of MeCP2 from nucleus to cytoplasm. 4 pMeCP2 was colocalized with NSCs marker protein nestin in the ischemic basal ganglia at 3 d after MCAO; pMeCP2 was colocalized with the neuronal marker MAP-2 in the ischemic basal ganglia at 1 week after MCAO. Conclusion Ischemic stroke-induced MeCP2 phosphorylation was able to alter the spatial distribution of MeCP2, transferring it from nucleus to cytoplasm and affecting its biological functions. This study further improved our awareness of brain neurogenesis in adult animals

  1. Resolving basal ganglia calcification in hereditary hypomagnesemia with secondary hypocalcemia due to a novel TRMP6 gene mutation

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    Abdelhadi M Habeb

    2012-01-01

    Full Text Available Hereditary hypomagnesemia with secondary hypocalcemia (HSH is a rare condi-tion caused by mutations in the Transient Receptor Potential Melastatin 6 (TRMP6 gene. Patients usually present during early infancy with symptomatic hypocalcemia; however, intracranial calcification has not been previously reported in HSH. We report on a three-month-old Saudi girl who presented with hypocalcemic convulsions and was initially treated as nutritional rickets. However, further biochemical analysis of blood and urine were suggestive of HSH. This diagnosis was confirmed by mutation analysis, which identified a novel homozygous frame shift mutation (ins 2999T of the TRMP6 gene. A computed tomography brain scan, done around the time of diagnosis, identified bilateral basal ganglia calcification (BGC. Her serum calcium and the BGC improved with magnesium replacement. BGC can be added as a new feature of HSH and the case highlights the importance of measuring serum Mg in patients with hypocalcemic convulsions, particularly in children of consanguineous parents.

  2. Changes in total cell numbers of the basal ganglia in patients with multiple system atrophy - A stereological study

    DEFF Research Database (Denmark)

    Salvesen, Lisette; Ullerup, Birgitte H; Sunay, Fatma B;

    2014-01-01

    Total numbers of neurons, oligodendrocytes, astrocytes, and microglia in the basal ganglia and red nucleus were estimated in brains from 11 patients with multiple system atrophy (MSA) and 11 age- and gender-matched control subjects with unbiased stereological methods. Compared to the control...... subjects, the MSA patients had a substantially lower number of neurons in the substantia nigra (p=0.001), putamen (p=0.001), and globus pallidus (pputamen (p=0.......04) and globus pallidus (p=0.01). In the MSA brains the total number of astrocytes was significantly higher in the putamen (p=0.04) and caudate nucleus (p=0.01). In all examined regions a higher number of microglia were found in the MSA brains with the greatest difference observed in the otherwise unaffected red...

  3. Dynamic stereotypic responses of basal ganglia neurons to subthalamic nucleus high frequency stimulation in the parkinsonian primate

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    Anan eMoran

    2011-04-01

    Full Text Available Deep brain stimulation in the subthalamic nucleus (STN is a well-established therapy for patients with severe Parkinson‟s disease (PD; however, its mechanism of action is still unclear. In this study we explored static and dynamic activation patterns in the basal ganglia during high frequency macro-stimulation of the STN. Extracellular multi-electrode recordings were performed in primates rendered parkinsonian using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Recordings were preformed simultaneously in the STN and the globus pallidus externus and internus. Single units were recorded preceding and during the stimulation. During the stimulation, STN mean firing rate dropped significantly, while pallidal mean firing rates did not change significantly. The vast majority of neurons across all three nuclei displayed stimulation driven modulations, which were stereotypic within each nucleus but differed across nuclei. The predominant response pattern of STN neurons was somatic inhibition. However, most pallidal neurons demonstrated synaptic activation patterns. A minority of neurons across all nuclei displayed axonal activation. Temporal dynamics were observed in the response to stimulation over the first 10 seconds in the STN and over the first 30 seconds in the pallidum. In both pallidal segments, the synaptic activation response patterns underwent delay and decay of the magnitude of the peak response due to short term synaptic depression. We suggest that during STN macro stimulation the STN goes through a functional ablation as its upper bound on information transmission drops significantly. This notion is further supported by the evident dissociation between the stimulation driven pre-synaptic STN somatic inhibition and the post-synaptic axonal activation of its downstream targets. Thus, basal ganglia output maintains its firing rate while losing the deleterious effect of the STN. This may be a part of the mechanism leading to the beneficial

  4. Mechanism of Parkinsonian Neuronal Oscillations in the Primate Basal Ganglia: Some Considerations Based on Our Recent Work

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    Atsushi eNambu

    2014-05-01

    Full Text Available Accumulating evidence suggests that abnormal neuronal oscillations in the basal ganglia contribute to the manifestation of parkinsonian symptoms. In this article, we would like to summarize our recent work on the mechanism underlying abnormal oscillations in the parkinsonian state and discuss its significance in pathophysiology of Parkinson’s disease. We recorded neuronal activity in the basal ganglia of parkinsonian monkeys treated with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine. Systemic administration of L-DOPA alleviated parkinsonian motor signs and decreased abnormal neuronal oscillations (8-15 Hz in the internal (GPi and external (GPe segments of the globus pallidus and the subthalamic nucleus (STN. Inactivation of the STN by muscimol (GABAA receptor agonist injection also ameliorated parkinsonian signs and suppressed GPi oscillations. Blockade of glutamatergic inputs to the STN by local microinjection of a mixture of 3-(2-carboxypiperazin-4-yl-propyl-1-phosphonic acid (glutamatergic NMDA receptor antagonist and 1,2,3,4-tetrahydro-6-nitro-2,3- dioxo-benzo[f]quinoxaline-7-sulfonamide (glutamatergic AMPA/kainate receptor antagonist suppressed neuronal oscillations in the STN. The STN oscillations were further attenuated by the blockade of GABAergic neurotransmission from the GPe to the STN by muscimol inactivation of the GPe. These results suggest that cortical glutamatergic inputs to the STN and reciprocal GPe-STN interconnections are both important for the generation and amplification of the oscillatory activity of GPe and STN neurons in the dopamine-depleted state. The oscillatory activity in the STN is subsequently transmitted to the GPi and may contribute to manifestation of parkinsonian symptoms.

  5. Behavioural effects of basal ganglia rho-kinase inhibition in the unilateral 6-hydroxydopamine rat model of Parkinson's disease.

    Science.gov (United States)

    Inan, Salim Yalcin; Soner, Burak Cem; Sahin, Ayse Saide

    2016-08-01

    Parkinson's disease (PD) is one of the most common neurodegenerative disorders, which affects more than six million people in the world. While current available pharmacological therapies for PD in the early stages of the disease usually improve motor symptoms, they cause side effects, such as fluctuations and dyskinesias in the later stages. In this later stage, high frequency deep brain stimulation of the subthalamic nucleus (STN-DBS) is a treatment option which is most successful to treat drug resistant advanced PD. It has previously been demonstrated that activation of Rho/Rho-kinase pathway is involved in the dopaminergic cell degeneration which is one of the main characteristics of PD pathology. In addition, the involvement of this pathway has been suggested in diverse cellular events in the central nervous system; such as epilepsy, anxiety-related behaviors, regulation of dendritic and axonal morphology, antinociception, subarachnoid haemorrhage, spinal cord injury and amyotrophic lateral sclerosis. However, up to date, to our knowledge there are no previous reports showing the beneficial effects of the potent Rho-kinase inhibitor Y-27632 in the 6-hydroxydopamine (6-OHDA) rat model of PD. Therefore, in the present study, we investigated the behavioural effects of basal ganglia Y-27632 microinjections in this PD model. Our results indicated that basal ganglia Y-27632 microinjections significantly decreased the number of contralateral rotations-induced by apomorphine, significantly increased line crossings in the open-field test, contralateral forelimb use in the limb-use asymmetry test and contralateral tape playing time in the somatosensory asymmetry test, which may suggest that Y-27632 could be a potentially active antiparkinsonian agent. PMID:26996632

  6. Mean-field modeling of the basal ganglia-thalamocortical system. I Firing rates in healthy and parkinsonian states.

    Science.gov (United States)

    van Albada, S J; Robinson, P A

    2009-04-21

    Parkinsonism leads to various electrophysiological changes in the basal ganglia-thalamocortical system (BGTCS), often including elevated discharge rates of the subthalamic nucleus (STN) and the output nuclei, and reduced activity of the globus pallidus external (GPe) segment. These rate changes have been explained qualitatively in terms of the direct/indirect pathway model, involving projections of distinct striatal populations to the output nuclei and GPe. Although these populations partly overlap, evidence suggests dopamine depletion differentially affects cortico-striato-pallidal connection strengths to the two pallidal segments. Dopamine loss may also decrease the striatal signal-to-noise ratio, reducing both corticostriatal coupling and striatal firing thresholds. Additionally, nigrostriatal degeneration may cause secondary changes including weakened lateral inhibition in the GPe, and mesocortical dopamine loss may decrease intracortical excitation and especially inhibition. Here a mean-field model of the BGTCS is presented with structure and parameter estimates closely based on physiology and anatomy. Changes in model rates due to the possible effects of dopamine loss listed above are compared with experiment. Our results suggest that a stronger indirect pathway, possibly combined with a weakened direct pathway, is compatible with empirical evidence. However, altered corticostriatal connection strengths are probably not solely responsible for substantially increased STN activity often found. A lower STN firing threshold, weaker intracortical inhibition, and stronger striato-GPe inhibition help explain the relatively large increase in STN rate. Reduced GPe-GPe inhibition and a lower GPe firing threshold can account for the comparatively small decrease in GPe rate frequently observed. Changes in cortex, GPe, and STN help normalize the cortical rate, also in accord with experiments. The model integrates the basal ganglia into a unified framework along with an

  7. A patient with Moyamoya-like vessels after radiation therapy for a tumor in the basal ganglia

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    Ishiyama, Koichi; Tomura, Noriaki; Kato, Koki; Takahashi, Satoshi; Watarai, Jiro; Sasajima, Toshio; Mizoi, Kazuo [Akita Univ. (Japan). School of Medicine

    2001-10-01

    A patient with Moyamoya-like vessels after radiation therapy for treatment of a tumor in the basal ganglia is reported. He was diagnosed as Down syndrome at birth. He had a tumor in the left basal ganglionic region at 12 years of the age. The tumor increased in size at age 14. He underwent cerebral angiography, which did not show a stenosis nor occlusion of the internal carotid artery, anterior cerebral artery, nor the middle cerebral artery. He received radiation therapy with a total dose of 56 Gy. He presented a dressing apraxia at age 19. MRI showed cerebral infarction in the left temporo-occipital region. Right internal carotid angiography revealed a severe stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the right side. Moyamoya-like vessels were seen in the basal ganglionic region. Left internal carotid angiography also showed a stenosis of the internal carotid artery and anterior cerebral artery as well as a severe stenosis of the middle cerebral artery on the left side. Moyamoya-like vessels were seen in the basal ganglionic region. Leptomeningeal anastomose and transdural anastomose were bilaterally seen. These arterial occlusion and stenotic phenomenon corresponded to a previous radiation field. These Moyamoya-like vessels with arterial stenosis and occlusion were thought to be due to radiation-induced vasculopathy, because a previous cerebral angiography showed a normal caliber of cerebral arteries. This patient showed that patients with radiation therapy in their early childhood should be carefully observed considering the possibility of the phenomenon. (author)

  8. Singing can improve speech function in aphasics associated with intact right basal ganglia and preserve right temporal glucose metabolism: Implications for singing therapy indication.

    Science.gov (United States)

    Akanuma, Kyoko; Meguro, Kenichi; Satoh, Masayuki; Tashiro, Manabu; Itoh, Masatoshi

    2016-01-01

    Clinically, we know that some aphasic patients can sing well despite their speech disturbances. Herein, we report 10 patients with non-fluent aphasia, of which half of the patients improved their speech function after singing training. We studied ten patients with non-fluent aphasia complaining of difficulty finding words. All had lesions in the left basal ganglia or temporal lobe. They selected the melodies they knew well, but which they could not sing. We made a new lyric with a familiar melody using words they could not name. The singing training using these new lyrics was performed for 30 minutes once a week for 10 weeks. Before and after the training, their speech functions were assessed by language tests. At baseline, 6 of them received positron emission tomography to evaluate glucose metabolism. Five patients exhibited improvements after intervention; all but one exhibited intact right basal ganglia and left temporal lobes, but all exhibited left basal ganglia lesions. Among them, three subjects exhibited preserved glucose metabolism in the right temporal lobe. We considered that patients who exhibit intact right basal ganglia and left temporal lobes, together with preserved right hemispheric glucose metabolism, might be an indication of the effectiveness of singing therapy.

  9. fMRI of Cocaine Self-Administration in Macaques Reveals Functional Inhibition of Basal Ganglia

    OpenAIRE

    Mandeville, Joseph B.; Choi, Ji-Kyung; Jarraya, Bechir; Rosen, Bruce R.; Jenkins, Bruce G.; Vanduffel, Wim

    2011-01-01

    Disparities in cocaine-induced neurochemical and metabolic responses between human beings and rodents motivate the use of non-human primates (NHP) to model consequences of repeated cocaine exposure in human subjects. To characterize the functional response to cocaine infusion in NHP brain, we employed contrast-enhanced fMRI during both non-contingent injection of drug and self-administration of cocaine in the magnet. Cocaine robustly decreased cerebral blood volume (CBV) throughout basal gang...

  10. The Relationship of Hematoma Size and Mortality in Non-Traumatic Intra-Cerebral Hemorrhages in Basal Ganglia

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    P. Ahmadi

    2006-04-01

    Full Text Available Introduction & Objective: Among all of the neurologic diseases in adult life, the cerebrovascular disease (CVD is the most common and important ones. Intracerebral hemorrhage (ICH in basal ganglia (BG is one of the common and major types of CVD. The relations between clot size and mortality rate, in different parts of the brain, has been addressed by several researchers. It is unclear whether such a relationship is in BG. Therefore this study was designed to find a formula that predicts outcome of hemorrhage based on clot size in BG.Materials & Methods: This descriptive-comparative study that was carried out prospectively, conducted on all 63 patients who admitted to the hospital during one year, with definite diagnosis of ICH in BG. After urgent CT scanning, the size of hematoma was determined by scan images. Routine treatment was uniform for all patients. Focal signs and consciousness state were assessed in the first and last days of admission. The data were analyzed using descriptive statistics, frequency tables and chi-square and T- test. Results: 33% of patients died. Hematoma size in 70% of them was larger than 5cm and in other 30% smaller. None of the hematoma with less than 4cm size was fatal. In patients with clots of 5cm or larger, the mortality was 100%. Conclusion: The results indicated that, there was meaningful relationship between hematoma size and mortality, in BG hemorrhages. So the clot size can be used as a factor in predicting hemorrhage outcome in BG.

  11. Hypernasality associated with basal ganglia dysfunction: evidence from Parkinson’s disease and Huntington’s disease

    Science.gov (United States)

    Novotný, Michal; Čmejla, Roman; Růžičková, Hana; Klempíř, Jiří; Růžička, Evžen

    2016-01-01

    Background Although increased nasality can originate from basal ganglia dysfunction, data regarding hypernasality in Parkinson’s disease (PD) and Huntington’s disease (HD) are very sparse. The aim of the current study was to analyze acoustic and perceptual correlates of velopharyngeal seal closure in 37 PD and 37 HD participants in comparison to 37 healthy control speakers. Methods Acoustical analysis was based on sustained phonation of the vowel /i/ and perceptual analysis was based on monologue. Perceptual analysis was performed by 10 raters using The Great Ormond Street Speech Assessment ’98. Acoustic parameters related to changes in a 1/3-octave band centered on 1 kHz were proposed to reflect nasality level and behavior through utterance. Results Perceptual analysis showed the occurrence of mild to moderate hypernasality in 65% of PD, 89% of HD and 22% of control speakers. Based on acoustic analyses, 27% of PD, 54% of HD and 19% of control speakers showed an increased occurrence of hypernasality. In addition, 78% of HD patients demonstrated a high occurrence of intermittent hypernasality. Further results indicated relationships between the acoustic parameter representing fluctuation of nasality and perceptual assessment (r = 0.51, p Huntington Disease Rating Scale chorea composite subscore (r = 0.42, p = 0.01). Conclusions In conclusion the acoustic assessment showed that abnormal nasality was not a common feature of PD, whereas patients with HD manifested intermittent hypernasality associated with chorea. PMID:27703866

  12. Exploring the cognitive and motor functions of the basal ganglia: an integrative review of computational cognitive neuroscience models

    Science.gov (United States)

    Helie, Sebastien; Chakravarthy, Srinivasa; Moustafa, Ahmed A.

    2013-01-01

    Many computational models of the basal ganglia (BG) have been proposed over the past twenty-five years. While computational neuroscience models have focused on closely matching the neurobiology of the BG, computational cognitive neuroscience (CCN) models have focused on how the BG can be used to implement cognitive and motor functions. This review article focuses on CCN models of the BG and how they use the neuroanatomy of the BG to account for cognitive and motor functions such as categorization, instrumental conditioning, probabilistic learning, working memory, sequence learning, automaticity, reaching, handwriting, and eye saccades. A total of 19 BG models accounting for one or more of these functions are reviewed and compared. The review concludes with a discussion of the limitations of existing CCN models of the BG and prescriptions for future modeling, including the need for computational models of the BG that can simultaneously account for cognitive and motor functions, and the need for a more complete specification of the role of the BG in behavioral functions. PMID:24367325

  13. Interaction between the 5-HT system and the basal ganglia: Functional implication and therapeutic perspective in Parkinson’s disease

    Directory of Open Access Journals (Sweden)

    Cristina eMiguelez

    2014-03-01

    Full Text Available The neurotransmitter serotonin (5-HT has a multifaceted function in the modulation of information processing through the activation of multiple receptor families, including G-protein-coupled receptor subtypes (5-HT1, 5-HT2, 5-HT4-7 and ligand-gated ion channels (5-HT3. The largest population of serotonergic neurons is located in the midbrain, specifically in the raphe nuclei. Although the medial and dorsal raphe nucleus (DRN share common projecting areas, in the basal ganglia (BG nuclei serotonergic innervations come mainly from the DRN. The BG are a highly organized network of subcortical nuclei composed of the striatum (caudate and putamen, subthalamic nucleus (STN, internal and external globus pallidus (or entopeduncular nucleus in rodents, GPi/EP and GPe and substantia nigra (pars compacta, SNc, and pars reticulata, SNr. The BG are part of the cortico-BG-thalamic circuits, which play a role in many functions like motor control, emotion, and cognition and are critically involved in diseases such as Parkinson’s disease. This review provides an overview of serotonergic modulation of the BG at the functional level and a discussion of how this interaction may be relevant to treating Parkinson’s disease and the motor complications induced by chronic treatment with L-DOPA.

  14. Novel SLC19A3 Promoter Deletion and Allelic Silencing in Biotin-Thiamine-Responsive Basal Ganglia Encephalopathy.

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    Irene Flønes

    Full Text Available Biotin-thiamine responsive basal ganglia disease is a severe, but potentially treatable disorder caused by mutations in the SLC19A3 gene. Although the disease is inherited in an autosomal recessive manner, patients with typical phenotypes carrying single heterozygous mutations have been reported. This makes the diagnosis uncertain and may delay treatment.In two siblings with early-onset encephalopathy dystonia and epilepsy, whole-exome sequencing revealed a novel single heterozygous SLC19A3 mutation (c.337T>C. Although Sanger-sequencing and copy-number analysis revealed no other aberrations, RNA-sequencing in brain tissue suggested the second allele was silenced. Whole-genome sequencing resolved the genetic defect by revealing a novel 45,049 bp deletion in the 5'-UTR region of the gene abolishing the promoter. High dose thiamine and biotin therapy was started in the surviving sibling who remains stable. In another patient two novel compound heterozygous SLC19A3 mutations were found. He improved substantially on thiamine and biotin therapy.We show that large genomic deletions occur in the regulatory region of SLC19A3 and should be considered in genetic testing. Moreover, our study highlights the power of whole-genome sequencing as a diagnostic tool for rare genetic disorders across a wide spectrum of mutations including non-coding large genomic rearrangements.

  15. Usefulness of computed tomography in the diagnosis of cryptococcal meningoencephalitis. Multiple low density lesions in the basal ganglia and corona radiata

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    Tokumaru, Yukio; Kojima, Shigeyuki; Yamada, Tatsuo; Ito, Naoki; Hirayama, Keizo (Chiba Univ. (Japan). School of Medicine)

    1982-11-01

    In 2 cases of cryptococcal meningoencephalitis, we found multiple round low density lesions in the basal ganglia and corona radiata by CT scan. Both cases were treated successfully with amphotericin B and 5-fluorocytosine. Pathologically, cryptococcal meningoencephalitis usually shows two types of lesions: one being gelatinous and the other granulomatous. The former is a cystic lesion which mainly invades the cerebral cortex, dentate nucleus and basal ganglia; the latter is a granuloma as a result of histological reaction common to any of fungal organism. In granulomatous lesions, CT scan usually shows a high density or ring enhancement by contrast medium. In our 2 cases, CT scan showed multiple low density spots with no enhancement. We thought that they might represent gelatinous lesions. We stressed the importance of checking serial CT scans for the diagnosis of chronic meningoencephalitis of unknown etiology.

  16. Bee Venom Alleviates Motor Deficits and Modulates the Transfer of Cortical Information through the Basal Ganglia in Rat Models of Parkinson's Disease.

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    Nicolas Maurice

    Full Text Available Recent evidence points to a neuroprotective action of bee venom on nigral dopamine neurons in animal models of Parkinson's disease (PD. Here we examined whether bee venom also displays a symptomatic action by acting on the pathological functioning of the basal ganglia in rat PD models. Bee venom effects were assessed by combining motor behavior analyses and in vivo electrophysiological recordings in the substantia nigra pars reticulata (SNr, basal ganglia output structure in pharmacological (neuroleptic treatment and lesional (unilateral intranigral 6-hydroxydopamine injection PD models. In the hemi-parkinsonian 6-hydroxydopamine lesion model, subchronic bee venom treatment significantly alleviates contralateral forelimb akinesia and apomorphine-induced rotations. Moreover, a single injection of bee venom reverses haloperidol-induced catalepsy, a pharmacological model reminiscent of parkinsonian akinetic deficit. This effect is mimicked by apamin, a blocker of small conductance Ca2+-activated K+ (SK channels, and blocked by CyPPA, a positive modulator of these channels, suggesting the involvement of SK channels in the bee venom antiparkinsonian action. In vivo electrophysiological recordings in the substantia nigra pars reticulata (basal ganglia output structure showed no significant effect of BV on the mean neuronal discharge frequency or pathological bursting activity. In contrast, analyses of the neuronal responses evoked by motor cortex stimulation show that bee venom reverses the 6-OHDA- and neuroleptic-induced biases in the influence exerted by the direct inhibitory and indirect excitatory striatonigral circuits. These data provide the first evidence for a beneficial action of bee venom on the pathological functioning of the cortico-basal ganglia circuits underlying motor PD symptoms with potential relevance to the symptomatic treatment of this disease.

  17. Believer-Skeptic Meets Actor-Critic: Rethinking the Role of Basal Ganglia Pathways during Decision-Making and Reinforcement Learning

    OpenAIRE

    Dunovan, Kyle; Verstynen, Timothy

    2016-01-01

    The flexibility of behavioral control is a testament to the brain's capacity for dynamically resolving uncertainty during goal-directed actions. This ability to select actions and learn from immediate feedback is driven by the dynamics of basal ganglia (BG) pathways. A growing body of empirical evidence conflicts with the traditional view that these pathways act as independent levers for facilitating (i.e., direct pathway) or suppressing (i.e., indirect pathway) motor output, suggesting inste...

  18. Combining self-organizing maps with mixtures of experts: Application to an Actor-critic model of reinforcement learning in the Basal Ganglia

    OpenAIRE

    Khamassi, Mehdi; Martinet, Louis-Emmanuel; Guillot, Agnés

    2006-01-01

    International audience In a reward-seeking task performed in a continuous environment, our previous work compared several Actor-Critic architectures implementing dopamine-like reinforcement learning mechanisms in the rat's basal ganglia. The task complexity imposes the coordination of several submodules, each module being an expert trained in a particular subset of the task. Our results illustrated the consequences of different hypotheses about the management of Actor-Critic submodules. We...

  19. A network model of basal ganglia for understanding the roles of dopamine and serotonin in reward-punishment-risk based decision making

    OpenAIRE

    Pragathi Priyadharsini Balasubramani; Srinivasa eChakravarthy; Balaraman eRavindran; Moustafa, Ahmed A.

    2015-01-01

    There is significant evidence that in addition to reward-punishment based decision making, the Basal Ganglia (BG) contributes to risk-based decision making (Balasubramani et al., 2014). Despite this evidence, little is known about the computational principles and neural correlates of risk computation in this subcortical system. We have previously proposed a reinforcement learning (RL)-based model of the BG that simulates the interactions between dopamine (DA) and serotonin (5HT) in a diverse ...

  20. Common features of neural activity during singing and sleep periods in a basal ganglia nucleus critical for vocal learning in a juvenile songbird.

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    Shin Yanagihara

    Full Text Available Reactivations of waking experiences during sleep have been considered fundamental neural processes for memory consolidation. In songbirds, evidence suggests the importance of sleep-related neuronal activity in song system motor pathway nuclei for both juvenile vocal learning and maintenance of adult song. Like those in singing motor nuclei, neurons in the basal ganglia nucleus Area X, part of the basal ganglia-thalamocortical circuit essential for vocal plasticity, exhibit singing-related activity. It is unclear, however, whether Area X neurons show any distinctive spiking activity during sleep similar to that during singing. Here we demonstrate that, during sleep, Area X pallidal neurons exhibit phasic spiking activity, which shares some firing properties with activity during singing. Shorter interspike intervals that almost exclusively occurred during singing in awake periods were also observed during sleep. The level of firing variability was consistently higher during singing and sleep than during awake non-singing states. Moreover, deceleration of firing rate, which is considered to be an important firing property for transmitting signals from Area X to the thalamic nucleus DLM, was observed mainly during sleep as well as during singing. These results suggest that songbird basal ganglia circuitry may be involved in the off-line processing potentially critical for vocal learning during sensorimotor learning phase.

  1. Optogenetic stimulation in a computational model of the basal ganglia biases action selection and reward prediction error.

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    Pierre Berthet

    Full Text Available Optogenetic stimulation of specific types of medium spiny neurons (MSNs in the striatum has been shown to bias the selection of mice in a two choices task. This shift is dependent on the localisation and on the intensity of the stimulation but also on the recent reward history. We have implemented a way to simulate this increased activity produced by the optical flash in our computational model of the basal ganglia (BG. This abstract model features the direct and indirect pathways commonly described in biology, and a reward prediction pathway (RP. The framework is similar to Actor-Critic methods and to the ventral/dorsal distinction in the striatum. We thus investigated the impact on the selection caused by an added stimulation in each of the three pathways. We were able to reproduce in our model the bias in action selection observed in mice. Our results also showed that biasing the reward prediction is sufficient to create a modification in the action selection. However, we had to increase the percentage of trials with stimulation relative to that in experiments in order to impact the selection. We found that increasing only the reward prediction had a different effect if the stimulation in RP was action dependent (only for a specific action or not. We further looked at the evolution of the change in the weights depending on the stage of learning within a block. A bias in RP impacts the plasticity differently depending on that stage but also on the outcome. It remains to experimentally test how the dopaminergic neurons are affected by specific stimulations of neurons in the striatum and to relate data to predictions of our model.

  2. Optogenetic stimulation in a computational model of the basal ganglia biases action selection and reward prediction error.

    Science.gov (United States)

    Berthet, Pierre; Lansner, Anders

    2014-01-01

    Optogenetic stimulation of specific types of medium spiny neurons (MSNs) in the striatum has been shown to bias the selection of mice in a two choices task. This shift is dependent on the localisation and on the intensity of the stimulation but also on the recent reward history. We have implemented a way to simulate this increased activity produced by the optical flash in our computational model of the basal ganglia (BG). This abstract model features the direct and indirect pathways commonly described in biology, and a reward prediction pathway (RP). The framework is similar to Actor-Critic methods and to the ventral/dorsal distinction in the striatum. We thus investigated the impact on the selection caused by an added stimulation in each of the three pathways. We were able to reproduce in our model the bias in action selection observed in mice. Our results also showed that biasing the reward prediction is sufficient to create a modification in the action selection. However, we had to increase the percentage of trials with stimulation relative to that in experiments in order to impact the selection. We found that increasing only the reward prediction had a different effect if the stimulation in RP was action dependent (only for a specific action) or not. We further looked at the evolution of the change in the weights depending on the stage of learning within a block. A bias in RP impacts the plasticity differently depending on that stage but also on the outcome. It remains to experimentally test how the dopaminergic neurons are affected by specific stimulations of neurons in the striatum and to relate data to predictions of our model. PMID:24614169

  3. Action selection performance of a reconfigurable Basal Ganglia inspired model with Hebbian-Bayesian Go-NoGo connectivity

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    Pierre eBerthet

    2012-10-01

    Full Text Available Several studies have shown a strong involvement of the basal ganglia (BG in action selection and dopamine dependent learning. The dopaminergic signal to striatum, the input stage of the BG, has been commonly described as coding a reward prediction error (RPE, i.e. the difference between the predicted and actual reward. The RPE has been hypothesized to be critical in the modulation of the synaptic plasticity in cortico-striatal synapses in the direct and indirect pathway. We developed an abstract computational model of the BG, with a dual pathway structure functionally corresponding to the direct and indirect pathways, and compared its behaviour to biological data as well as other reinforcement learning models. The computations in our model are inspired by Bayesian inference, and the synaptic plasticity changes depend on a three factor Hebbian-Bayesian learning rule based on co-activation of pre- and post-synaptic units and on the value of the RPE. The model builds on a modified Actor-Critic architecture and implements the direct (Go and the indirect (NoGo pathway, as well as the reward prediction (RP system, acting in a complementary fashion. We investigated the performance of the model system when different configurations of the Go, NoGo and RP system were utilized, e.g. using only the Go, NoGo, or RP system, or combinations of those. Learning performance was investigated in several types of learning paradigms, such as learning-relearning, successive learning, stochastic learning, reversal learning and a two-choice task. The RPE and the activity of the model during learning were similar to monkey electrophysiological and behavioural data. Our results, however, show that there is not a unique best way to configure this BG model to handle well all the learning paradigms tested. We thus suggest that an agent might dynamically configure its action selection mode, possibly depending on task characteristics and also on how much time is available.

  4. Action selection performance of a reconfigurable basal ganglia inspired model with Hebbian-Bayesian Go-NoGo connectivity.

    Science.gov (United States)

    Berthet, Pierre; Hellgren-Kotaleski, Jeanette; Lansner, Anders

    2012-01-01

    Several studies have shown a strong involvement of the basal ganglia (BG) in action selection and dopamine dependent learning. The dopaminergic signal to striatum, the input stage of the BG, has been commonly described as coding a reward prediction error (RPE), i.e., the difference between the predicted and actual reward. The RPE has been hypothesized to be critical in the modulation of the synaptic plasticity in cortico-striatal synapses in the direct and indirect pathway. We developed an abstract computational model of the BG, with a dual pathway structure functionally corresponding to the direct and indirect pathways, and compared its behavior to biological data as well as other reinforcement learning models. The computations in our model are inspired by Bayesian inference, and the synaptic plasticity changes depend on a three factor Hebbian-Bayesian learning rule based on co-activation of pre- and post-synaptic units and on the value of the RPE. The model builds on a modified Actor-Critic architecture and implements the direct (Go) and the indirect (NoGo) pathway, as well as the reward prediction (RP) system, acting in a complementary fashion. We investigated the performance of the model system when different configurations of the Go, NoGo, and RP system were utilized, e.g., using only the Go, NoGo, or RP system, or combinations of those. Learning performance was investigated in several types of learning paradigms, such as learning-relearning, successive learning, stochastic learning, reversal learning and a two-choice task. The RPE and the activity of the model during learning were similar to monkey electrophysiological and behavioral data. Our results, however, show that there is not a unique best way to configure this BG model to handle well all the learning paradigms tested. We thus suggest that an agent might dynamically configure its action selection mode, possibly depending on task characteristics and also on how much time is available. PMID:23060764

  5. Striatal dopamine ramping may indicate flexible reinforcement learning with forgetting in the cortico-basal ganglia circuits.

    Science.gov (United States)

    Morita, Kenji; Kato, Ayaka

    2014-01-01

    It has been suggested that the midbrain dopamine (DA) neurons, receiving inputs from the cortico-basal ganglia (CBG) circuits and the brainstem, compute reward prediction error (RPE), the difference between reward obtained or expected to be obtained and reward that had been expected to be obtained. These reward expectations are suggested to be stored in the CBG synapses and updated according to RPE through synaptic plasticity, which is induced by released DA. These together constitute the "DA=RPE" hypothesis, which describes the mutual interaction between DA and the CBG circuits and serves as the primary working hypothesis in studying reward learning and value-based decision-making. However, recent work has revealed a new type of DA signal that appears not to represent RPE. Specifically, it has been found in a reward-associated maze task that striatal DA concentration primarily shows a gradual increase toward the goal. We explored whether such ramping DA could be explained by extending the "DA=RPE" hypothesis by taking into account biological properties of the CBG circuits. In particular, we examined effects of possible time-dependent decay of DA-dependent plastic changes of synaptic strengths by incorporating decay of learned values into the RPE-based reinforcement learning model and simulating reward learning tasks. We then found that incorporation of such a decay dramatically changes the model's behavior, causing gradual ramping of RPE. Moreover, we further incorporated magnitude-dependence of the rate of decay, which could potentially be in accord with some past observations, and found that near-sigmoidal ramping of RPE, resembling the observed DA ramping, could then occur. Given that synaptic decay can be useful for flexibly reversing and updating the learned reward associations, especially in case the baseline DA is low and encoding of negative RPE by DA is limited, the observed DA ramping would be indicative of the operation of such flexible reward learning.

  6. Striatal dopamine ramping may indicate flexible reinforcement learning with forgetting in the cortico-basal ganglia circuits

    Directory of Open Access Journals (Sweden)

    Kenji eMorita

    2014-04-01

    Full Text Available It has been suggested that the midbrain dopamine (DA neurons, receiving inputs from the cortico-basal ganglia (CBG circuits and the brainstem, compute reward prediction error (RPE, the difference between reward obtained or expected to be obtained and reward that had been expected to be obtained. These reward expectations are suggested to be stored in the CBG synapses and updated according to RPE through synaptic plasticity, which is induced by released DA. These together constitute the 'DA=RPE' hypothesis, which describes the mutual interaction between DA and the CBG circuits and serves as the primary working hypothesis in studying reward learning and value-based decision making. However, recent work has revealed a new type of DA signal that appears not to represent RPE. Specifically, it has been found in a reward-associated maze task that striatal DA concentration primarily shows a gradual increase towards the goal. We explored whether such ramping DA could be explained by extending the 'DA=RPE' hypothesis by taking into account biological properties of the CBG circuits. In particular, we examined effects of possible time-dependent decay of DA-dependent plastic changes of synaptic strengths by incorporating decay of learned values into the RPE-based reinforcement learning model and simulating reward learning tasks. We then found that incorporation of such a decay dramatically changes the model's behavior, causing gradual ramping of RPE. Moreover, we further incorporated magnitude-dependence of the rate of decay, which could potentially be in accord with some past observations, and found that near-sigmoidal ramping of RPE, resembling the observed DA ramping, could then occur. Given that synaptic decay can be useful for flexibly reversing and updating the learned reward associations, especially in case the baseline DA is low and encoding of negative RPE by DA is limited, the observed DA ramping would be indicative of the operation of such

  7. Effect of Levodopa Chronic Administration on Behavioral Changes and Fos Expression in Basal Ganglia in Rat Model of PD

    Institute of Scientific and Technical Information of China (English)

    徐岩; 孙圣刚; 曹学兵

    2003-01-01

    To study behavioral character and changes of neuronal activity in the basal ganglia of ratmodel of levodopa-induced dyskinesia, unilateral 6-hydroxydopamine lesioned rat model of Parkin-son disease (PD) was treated with levodopa/benserazide twice daily for 4 weeks and the behaviorobserved on the 1st, 3rd, 4th, 7th, 9th, 10th, 14th, 21st and 28th day. The animals were sacri-ficed and immunohistochemical technique was used to measure the changes of Fos expression in thecaudate putamen (CPU), globus pallidus (GP) and sensorimotor area of cerebral cortex 2 h afterthe last treatment. The results showed that pulsatile treatment with a subthreshold dose of levodo-pa gradually induced abnormal involuntary movement (AIM), including stereotypy (limb dyskine-sia, axial dystonia and masticatory dyskinesia) towards the side contralateral to the dopamine-den-ervated striatum and increased contraversive rotation. The motor pattern of each subtype was highlystereotypic across individual rats, and the proportion of each subtype was not consistent among in-dividual rats. Fos positive nuclei in the CPU and GP were increased by levodopa acute administra-tion, and more remarkably in the CPU, but not in the cerebral cortex. After repeated levodopatreatment, Fos positive nuclei were reduced remarkably in the CPU, but were increased in the GPand cerebral cortex. It was concluded that the neural mechanisms underlying levodopa induced AIMin rat model of PD was very similar to those seen in levodopa-induced dyskinesia (LID) in PD pa-tients and MPTP-lesioned monkeys, and increased striatopallidal neuronal activity might be involvedin occurrence of LID.

  8. Emergent structured transition from variation to repetition in a biologically-plausible model of learning in basal ganglia.

    Directory of Open Access Journals (Sweden)

    Ashvin eShah

    2014-02-01

    Full Text Available Often, when animals encounter an unexpected sensory event, they transition from executing a variety of movements to repeating the movement(s that may have caused the event. According to a recent theory of action discovery (Redgrave and Gurney 2006, repetition allows the animal to represent those movements, and the outcome, as an action for later recruitment. The transition from variation to repetition often follows a non-random, structured, pattern. While the structure of the pattern can be explained by sophisticated cognitive mechanisms, simpler mechanisms based on dopaminergic modulation of basal ganglia (BG activity are thought to underlie action discovery (Redgrave and Gurney 2006. In this paper we ask the question: can simple BG-mediated mechanisms account for a structured transition from variation to repetition, or are more sophisticated cognitive mechanisms always necessary?To address this question, we present a computational model of BG-mediated biasing of behavior. In our model, unlike most other models of BG function, the BG biases behaviour through modulation of cortical response to excitation; many possible movements are represented by the cortical area; and excitation to the cortical area is topographically-organized. We subject the model to simple reaching tasks, inspired by behavioral studies, in which a location to which to reach must be selected. Locations within a target area elicit a reinforcement signal. A structured transition from variation to repetition emerges from simple BG-mediated biasing of cortical response to excitation. We show how the structured pattern influences behavior in simple and complicated tasks. We also present analyses that describe the structured transition from variation to repetition due to BG-mediated biasing and from biasing that would be expected from a type of cognitive biasing, allowing us to compare behaviour resulting from these types of biasing and make connections with future behavioural

  9. The anatomy of transsylvian fissure-insular surgical approach for removal of intracerebral hematoma in basal ganglia region%经外侧裂-岛叶清除基底节血肿手术入路的解剖

    Institute of Scientific and Technical Information of China (English)

    冯三平; 冯继

    2012-01-01

    bifurcation of the M1 segment usually located at the level of the limen insulae; and the M2 of MCA appeared as a shape of " v" or " mesh" , expanding backward and upward on the surface of insula in a shape of fan, and terminal tiny perforating arteries of the M2 segments provided the supply to the insula; internal surface of the insula covered the basal ganglia, inner vesicle and thalamus. In this study, we found that the middle horizontal section of the insula, the middle and post short gyrus pointed to inward the widest part of the putamen and also the genu of internal capsule. Conclusion A knowledge of the anatomy of the sylvian fissure-insular surgical approach is helpful for the clearing of intracerebral hematomas in basal ganglia region.

  10. MR spectroscopy-based brain metabolite profiling in propionic acidaemia: metabolic changes in the basal ganglia during acute decompensation and effect of liver transplantation

    Directory of Open Access Journals (Sweden)

    McKiernan Patrick J

    2011-05-01

    Full Text Available Abstract Background Propionic acidaemia (PA results from deficiency of Propionyl CoA carboxylase, the commonest form presenting in the neonatal period. Despite best current management, PA is associated with severe neurological sequelae, in particular movement disorders resulting from basal ganglia infarction, although the pathogenesis remains poorly understood. The role of liver transplantation remains controversial but may confer some neuro-protection. The present study utilises quantitative magnetic resonance spectroscopy (MRS to investigate brain metabolite alterations in propionic acidaemia during metabolic stability and acute encephalopathic episodes. Methods Quantitative MRS was used to evaluate brain metabolites in eight children with neonatal onset propionic acidaemia, with six elective studies acquired during metabolic stability and five studies during acute encephalopathic episodes. MRS studies were acquired concurrently with clinically indicated MR imaging studies at 1.5 Tesla. LCModel software was used to provide metabolite quantification. Comparison was made with a dataset of MRS metabolite concentrations from a cohort of children with normal appearing MR imaging. Results MRI findings confirm the vulnerability of basal ganglia to infarction during acute encephalopathy. We identified statistically significant decreases in basal ganglia glutamate+glutamine and N-Acetylaspartate, and increase in lactate, during encephalopathic episodes. In white matter lactate was significantly elevated but other metabolites not significantly altered. Metabolite data from two children who had received liver transplantation were not significantly different from the comparator group. Conclusions The metabolite alterations seen in propionic acidaemia in the basal ganglia during acute encephalopathy reflect loss of viable neurons, and a switch to anaerobic respiration. The decrease in glutamine + glutamate supports the hypothesis that they are consumed to

  11. Basal ganglia dysfunction

    Science.gov (United States)

    ... overdose Head injury Infection Liver disease Metabolic problems Multiple sclerosis Poisoning with copper, manganese, or other heavy metals Side effects of certain medications Stroke Tumors Many brain disorders are associated with ...

  12. Probing the Role of Medication, DBS Electrode Position, and Antidromic Activation on Impulsivity Using a Computational Model of Basal Ganglia.

    Science.gov (United States)

    Mandali, Alekhya; Chakravarthy, V Srinivasa

    2016-01-01

    Everyday, we encounter situations where available choices are nearly equally rewarding (high conflict) calling for some tough decision making. Experimental recordings showed that the activity of Sub Thalamic Nucleus (STN) increases during such situations providing the extra time needed to make the right decision, teasing apart the most rewarding choice from the runner up closely trailing behind. This prolonged deliberation necessary for decision making under high conflict was absent in Parkinson's disease (PD) patients who underwent Deep Brain Stimulation (DBS) surgery of STN. In an attempt to understand the underlying cause of such adverse response, we built a 2D spiking network model (50 × 50 lattice) of Basal ganglia incorporating the key nuclei. Using the model we studied the Probabilistic learning task (PLT) in untreated, treated (L-Dopa and Dopamine Agonist) and STN-DBS PD conditions. Based on the experimental observation that dopaminergic activity is analogous to temporal difference (TD) and induces cortico-striatal plasticity, we introduced learning in the cortico-striatal weights. The results show that healthy and untreated conditions of PD model were able to more or less equally select (avoid) the rewarding (punitive) choice, a behavior that was absent in treated PD condition. The time taken to select a choice in high conflict trials was high in normal condition, which is in agreement with experimental results. The treated PD (Dopamine Agonist) patients made impulsive decisions (small reaction time) which in turn led to poor performance. The underlying cause of the observed impulsivity in DBS patients was studied in the model by (1) varying the electrode position within STN, (2) causing antidromic activation of GPe neurons. The effect of electrode position on reaction time was analyzed by studying the activity of STN neurons where, a decrease in STN neural activity was observed for certain electrode positions. We also observed that a higher antidromic

  13. Probing the Role of Medication, DBS Electrode Position, and Antidromic Activation on Impulsivity Using a Computational Model of Basal Ganglia

    Science.gov (United States)

    Mandali, Alekhya; Chakravarthy, V. Srinivasa

    2016-01-01

    Everyday, we encounter situations where available choices are nearly equally rewarding (high conflict) calling for some tough decision making. Experimental recordings showed that the activity of Sub Thalamic Nucleus (STN) increases during such situations providing the extra time needed to make the right decision, teasing apart the most rewarding choice from the runner up closely trailing behind. This prolonged deliberation necessary for decision making under high conflict was absent in Parkinson's disease (PD) patients who underwent Deep Brain Stimulation (DBS) surgery of STN. In an attempt to understand the underlying cause of such adverse response, we built a 2D spiking network model (50 × 50 lattice) of Basal ganglia incorporating the key nuclei. Using the model we studied the Probabilistic learning task (PLT) in untreated, treated (L-Dopa and Dopamine Agonist) and STN-DBS PD conditions. Based on the experimental observation that dopaminergic activity is analogous to temporal difference (TD) and induces cortico-striatal plasticity, we introduced learning in the cortico-striatal weights. The results show that healthy and untreated conditions of PD model were able to more or less equally select (avoid) the rewarding (punitive) choice, a behavior that was absent in treated PD condition. The time taken to select a choice in high conflict trials was high in normal condition, which is in agreement with experimental results. The treated PD (Dopamine Agonist) patients made impulsive decisions (small reaction time) which in turn led to poor performance. The underlying cause of the observed impulsivity in DBS patients was studied in the model by (1) varying the electrode position within STN, (2) causing antidromic activation of GPe neurons. The effect of electrode position on reaction time was analyzed by studying the activity of STN neurons where, a decrease in STN neural activity was observed for certain electrode positions. We also observed that a higher antidromic

  14. Signal enhancement in the output stage of the basal ganglia by synaptic short-term plasticity in the direct, indirect and hyper direct pathways

    Directory of Open Access Journals (Sweden)

    Mikael eLindahl

    2013-06-01

    Full Text Available Many of the synapses in the basal ganglia display short-term plasticity. Still, computational models have not yet been used to investigate how this affects signaling. Here we use a model of the basal ganglia network, constrained by available data, to quantitatively investigate how synaptic short-term plasticity affects the substantia nigra reticulata (SNr, the basal ganglia output nucleus. We find that SNr becomes particularly responsive to the characteristic burst-like activity seen in both direct and indirect pathway striatal medium spiny neurons (MSN. As expected by the standard model, direct pathway MSNs are responsible for decreasing the activity in SNr. In particular, our simulations indicate that bursting in only a few percent of the direct pathway MSNs is sufficient for completely inhibiting SNr neuron activity. The standard model also suggests that SNr activity in the indirect pathway is controlled by MSNs disinhibiting the subthalamic nucleus (STN via the globus pallidus externa (GPe. Our model rather indicates that SNr activity is controlled by the direct GPe-SNr projections. This is partly because GPe strongly inhibits SNr but also due to depressing STN-SNr synapses. Furthermore, depressing GPe-SNr synapses allow the system to become sensitive to irregularly firing GPe subpopulations, as seen in dopamine depleted conditions, even when the GPe mean firing rate does not change. Similar to the direct pathway, simulations indicate that only a few percent of bursting indirect pathway MSNs can significantly increase the activity in SNr. Finally, the model predicts depressing STN-SNr synapses, since such an assumption explains experiments showing that a brief transient activation of the hyperdirect pathway generates a tri-phasic response in SNr, while a sustained STN activation has minor effects. This can be explained if STN-SNr synapses are depressing such that their effects are counteracted by the (known depressing GPe-SNr inputs.

  15. Deep frontal and periventricular age related white matter changes but not basal ganglia and infratentorial hyperintensities are associated with falls: cross sectional results from the LADIS study

    DEFF Research Database (Denmark)

    Blahak, C; Baezner, H; Pantoni, L;

    2009-01-01

    BACKGROUND: Global age related white matter changes (ARWMC) are associated with progressive gait disturbances and falls, hypothesised to result from interruptions of cortico-subcortical circuits controlling balance, posture and locomotion. METHODS: The location of ARWMC in a large cohort of elderly...... scale, in multivariate analysis, periventricular (p = 0.006) and frontal deep (p = 0.033) ARWMC were independently associated with falls. Furthermore, logistic regression identified frontal deep (p = 0.003) ARWMC, but not basal ganglia and infratentorial hyperintensities, as significantly associated...

  16. Basal ganglia volumes in drug-naive first-episode schizophrenia patients before and after short-term treatment with either a typical or an atypical antipsychotic drug

    DEFF Research Database (Denmark)

    Glenthoj, Andreas; Glenthoj, Birte Y; Mackeprang, Torben;

    2007-01-01

    The present study examined basal ganglia volumes in drug-naive first-episode schizophrenic patients before and after treatment with either a specific typical or atypical antipsychotic compound. Sixteen antipsychotic drug-naive and three minimally medicated first-episode schizophrenic patients...... or intracranial volume, the only significant difference between patients and controls was a Hemisphere x Group interaction for the caudate nucleus at baseline, with controls having larger left than right caudate nuclei and patients having marginally larger right than left caudate volumes. Within patients, the two...

  17. Basal ganglia stroke due to mild head trauma in pediatric age - clinical and therapeutic management: a case report and 10 year literature review

    Directory of Open Access Journals (Sweden)

    Salvati Maurizio

    2011-01-01

    Full Text Available Abstract Ischemia of the basal ganglia as an immediate consequence of minor head injury in children is rare ( Young patients should be closely monitored and treated conservatively with osmotic diuretics to reduce perilesional edema. At the same time, however, it is very important to exclude, by means of instrumental and laboratory studies, conditions that could favour the onset of ischemia, including emboligen heart disease, thrombophilia and acute traumatic arterial dissections. Generally speaking, the prognosis in these cases is good. The authors describe their experience treating a 10-month old baby girl, with a left lenticular nucleus ischemia and report a literature review.

  18. Neuromodulatory Adaptive Combination of Correlation-based Learning in Cerebellum and Reward-based Learning in Basal Ganglia for Goal-directed Behavior Control

    DEFF Research Database (Denmark)

    Dasgupta, Sakyasingha; Wörgötter, Florentin; Manoonpong, Poramate

    2014-01-01

    Goal-directed decision making in biological systems is broadly based on associations between conditional and unconditional stimuli. This can be further classified as classical conditioning (correlation-based learning) and operant conditioning (reward-based learning). A number of computational...... and experimental studies have well established the role of the basal ganglia in reward-based learning, where as the cerebellum plays an important role in developing specific conditioned responses. Although viewed as distinct learning systems, recent animal experiments point toward their complementary role...

  19. What does the mediodorsal thalamus do?

    Directory of Open Access Journals (Sweden)

    Anna S Mitchell

    2013-08-01

    Full Text Available Dense amnesia can result from damage to the medial diencephalon in humans and in animals. In humans this damage is diffuse and can include the mediodorsal nuclei of the thalamus. In animal models, lesion studies have confirmed the mediodorsal thalamus (MD has a role in memory and other cognitive tasks, although the extent of deficits is mixed. Anatomical tracing studies confirm at least three different subgroupings of the MD: medial, central and lateral, each differentially interconnected to the prefrontal cortex. Moreover, these subgroupings of the MD also receive differing inputs from other brain structures, including the basal ganglia thus the MD subgroupings form key nodes in interconnected frontal-striatal-thalamic neural circuits, integrating critical information within the prefrontal cortex. We will provide a review of data collected from non-human primates and rodents after selective brain injury to the whole of the MD as well as these subgroupings to highlight the extent of deficits in various cognitive tasks. This research highlights the neural basis of memory and cognitive deficits associated with the subgroupings of the MD and their interconnected neural networks. The evidence shows that the MD plays a critical role in many varied cognitive processes. In addition, the MD is actively processing information and integrating it across these neural circuits for successful cognition. Having established that the MD is critical for memory and cognition, further research is required to understand how the MD specifically influences these cognitive processing carried out by the brain.

  20. Gait variability and basal ganglia disorders: stride-to-stride variations of gait cycle timing in Parkinson's disease and Huntington's disease

    Science.gov (United States)

    Hausdorff, J. M.; Cudkowicz, M. E.; Firtion, R.; Wei, J. Y.; Goldberger, A. L.

    1998-01-01

    The basal ganglia are thought to play an important role in regulating motor programs involved in gait and in the fluidity and sequencing of movement. We postulated that the ability to maintain a steady gait, with low stride-to-stride variability of gait cycle timing and its subphases, would be diminished with both Parkinson's disease (PD) and Huntington's disease (HD). To test this hypothesis, we obtained quantitative measures of stride-to-stride variability of gait cycle timing in subjects with PD (n = 15), HD (n = 20), and disease-free controls (n = 16). All measures of gait variability were significantly increased in PD and HD. In subjects with PD and HD, gait variability measures were two and three times that observed in control subjects, respectively. The degree of gait variability correlated with disease severity. In contrast, gait speed was significantly lower in PD, but not in HD, and average gait cycle duration and the time spent in many subphases of the gait cycle were similar in control subjects, HD subjects, and PD subjects. These findings are consistent with a differential control of gait variability, speed, and average gait cycle timing that may have implications for understanding the role of the basal ganglia in locomotor control and for quantitatively assessing gait in clinical settings.

  1. Evaluation of depression status following basal ganglia infarction by diffusion tensor magnetic resonance imaging%磁共振弥散张量成像对基底节区梗死后抑郁状况的评估

    Institute of Scientific and Technical Information of China (English)

    涂加善; 刘振华; 黄凡衡; 陈爱敏; 蔡卫卫; 祝淑贞; 赵连旭

    2012-01-01

    Objective To study the anatomical abnormalities of basal ganglia and research their influence on depression status in patients with post stroke depression (PSD)by diffusion tensor imaging (DTI) of MRI.Methods Patients with basal ganglia infarction were recruited,and divided into groups of PSD and non depression control group by Hamilton Depression Rating Scale (HAMD) assessment. All the patients were evaluated with National Institute of Health Stroke Scale ( NIHSS). And the patients were checked by DTI sequence.Fractional anisotropy (FA),average diffusion coefficient (ADC) values and the number of nerve fiber were measured in bilateral caudatum,pallidum,putamen and thalamus.Results The score of NIHSS (6.29 ± 3.45 ) was significantly higher in PSD group than that in non-depression group (3.95 ± 1.90 ;t =2.219,P =0.036). No significant difference was found between the two groups for the DTI data of the basal ganglia nuclei ( t =0.056-1.618,all P > 0.05 ). Compared with contralateral construction (0.40 ± 0.02 ),the FA value decreased in the left putamen ( 0.37 ± 0.03 ) in the PSD group ( t =2.243,P =0.045 ).By Spearman correlations analysis,the HAMD score was positively correlated with NIHSS score ( r =0.464,P =0.017 ),and negatively correlated with the FA values of left pallidum (r=-0.563,P=0.005),right pallidum (r=-0.416,P=0.035) and left putamen (r =-0.428,P =0.029).Conclusions The occurrence of PSD was associated with neurological functional deficit following basal ganglia infarction.The depression level was correlated with the increasing of NIHSS score,the reductions in bilateral pallidum and left putamen FA values.This research contributes to evaluation of the PSD status in patients with basal ganglia infarction.%目的 利用磁共振弥散张量成像(DTI)技术研究基底节区梗死患者相关解剖结构的异常改变,评估卒中后抑郁( PSD)的状况.方法 选取基底节区梗死患者,依汉密尔顿抑郁量表(HAMD-24)

  2. Consequences of nigrostriatal denervation on the functioning of the basal ganglia in human and nonhuman primates: an in situ hybridization study of cytochrome oxidase subunit I mRNA.

    Science.gov (United States)

    Vila, M; Levy, R; Herrero, M T; Ruberg, M; Faucheux, B; Obeso, J A; Agid, Y; Hirsch, E C

    1997-01-15

    To examine the consequences of nigrostriatal denervation and chronic levodopa (L-DOPA) treatment on functional activity of the basal ganglia, we analyzed, using in situ hybridization, the cellular expression of the mRNA encoding for cytochrome oxidase subunit I (COI mRNA), a molecular marker for functional neuronal activity, in the basal ganglia. This analysis was performed in monkeys rendered parkinsonian by 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) Intoxication, some of which had been receiving L-DOPA, and in patients with Parkinson's disease (PD). In MPTP-intoxicated monkeys compared with control animals, COI mRNA expression was increased in the subthalamic nucleus (STN) and in the output nuclei of the basal ganglia, i.e., the internal segment of the globus pallidus and the substantia nigra pars reticulata. This increase was partially reversed by L-DOPA treatment. COI mRNA expression remained unchanged in the external segment of the globus pallidus (GPe). In PD patients, all of whom had been treated chronically by L-DOPA, COI mRNA expression in the analyzed basal ganglia structures was similar to that in control subjects. These results are in agreement with the accepted model of basal ganglia organization, to the extent that the output nuclei of the basal ganglia are considered to be overactive after nigrostriatal denervation, partly because of increased activity of excitatory afferents from the STN. Yet, our results would also seem to contradict this model, because the overactivity of the STN does not seem to be attributable to a hypoactivation of the GPe.

  3. Multivoxel magnetic resonance spectroscopy study of the bilateral basal ganglia regions in unilateral temporal lobe epilepsy patients%单侧颞叶癫病人双侧基底节区多体素MRS研究

    Institute of Scientific and Technical Information of China (English)

    刘兰; 刘筠; 许亮

    2016-01-01

    Objebtive To detect the metabolic changes in the bilateral basal ganglia regions of unilateral temporal lobe epilepsy (TLE) with multivoxel magnetic resonance spectroscopy. Methods Ten patients with left temporal lobe epilepsy, ten patients with right temporal lobe epilepsy, and 10 healthy volunteers were selected. Unilateral TLE were diagnosed based on clinical onset symptoms and EEG. The Liverpool seizure severity scale (LSSS) 2.0 was measured from all patients. Multivoxel 1H-MRS data were acquired by SIEMENS 3.0 superconducting MR scanner. Concentrations of N-acetyl aspartate (NAA), choline (Cho), and creatine (Cr) were measured symmetrically from bilateral head of caudate nucleus, putamen, and thalamus. The NAA/Cr and Cho/Cr ratios of each area of interest were calculated for inter-group statistical analysis. Pearson correlation analysis between metabolite ratios and LSSS 2.0 score were carried out. Results The NAA/Cr ratios of the left and right thalamus were 1.92 ±0.15 and 2.02 ±0.26, respectively, in the left TLE group;and 2.19 ±0.16 and 1.79±0.16, respectively, in the right TLE group. The ratios were significantly lower (P<0.05) than that of the control group which were 2.37±0.14 and 2.36±0.10, respectively. In the right TLE group, the NAA/Cr ratios of the ipsilateral thalamus was significant lower than that of the contralateral thalamus (1.79 ±0.16 vs 2.19 ±0.16, P<0.05). For TLE patients, the NAA/Cr ratios of the ipsilateral thalamus negatively correlated with LSSS 2.0 score (left TLE r=-0.667;right TLE r=-0.643, all P<0.05). Conclusion Patients with unilateral TLE have neuronal loss and/or dysfunction of bilateral thalamus, and both NAA/Cr ratios of the ipsilateral thalamus and LSSS 2.0 score can reflect the severity of seizures.%目的:采用多体素MRS探讨单侧颞叶癫日(TLE)病人双侧基底节区代谢物改变。方法选取根据临床发作症状和脑电图综合诊断的左侧TLE病人10例,右侧TLE病人10

  4. 脑梗死后基底节性失语的临床分析%Clinical analysis of basal ganglia aphasia after cerebral infarction

    Institute of Scientific and Technical Information of China (English)

    丁杰

    2013-01-01

    目的:探讨脑梗死后基底节性失语临床特点,为提高患者诊断与治疗效果提供可靠依据。方法9例脑梗死后基底节性失语患者均出现音韵节律、语调、看图命名、动作描述以及书写障碍,部分患者发生听理解及复述障碍,患者自发性语言可表现为流畅性或非流畅性。结果治疗后,其听、说、读能力均较治疗前显著提高,3例患者书写能力明显改善,6例患者书写能力未改善;临床治愈2例,显效7例,治疗总有效率为100.00%。结论脑梗死后基底节性失语患者均可出现不同程度的表达障碍,不利于其保持积极心态尽快恢复健康,根据患者具体症状采用针对性的康复训练措施,可显著提高患者语言能力,保障患者生活质量。%Objective To investigate the clinical characteristics of basal ganglia aphasia after cerebral infarction, and to provide reliable basis for diagnosis and treatment. Methods 9 patients with basal ganglia aphasia after cerebral infarction all appeared phonological rhythm,intonation, picture naming, action description and writing disorders, some patients appeared listen understand and repeat disorders,spontaneous language can be expressed as smooth or non-fluency. Results After the treatment,their listening,speaking,reading ability improved significantly,3 patients'ability to write were significantly improved,6 patients did not improve writing skills.2 cases were cured,7 cases were markedly,the total effective rate was 100.00%. Conclusion The basal ganglia aphasia after infarction patients all may have varying degrees of expression barriers,it's detrimental to their health restored as soon as possible,according to specific symptoms in patients to use targeted rehabilitation measures can significantly improve patients' language ability,protect the quality of patients'life.

  5. A Mathematical Model of Levodopa Medication Effect on Basal Ganglia in Parkinson's Disease: An Application to the Alternate Finger Tapping Task.

    Science.gov (United States)

    Baston, Chiara; Contin, Manuela; Calandra Buonaura, Giovanna; Cortelli, Pietro; Ursino, Mauro

    2016-01-01

    Malfunctions in the neural circuitry of the basal ganglia (BG), induced by alterations in the dopaminergic system, are responsible for an array of motor disorders and milder cognitive issues in Parkinson's disease (PD). Recently Baston and Ursino (2015a) presented a new neuroscience mathematical model aimed at exploring the role of basal ganglia in action selection. The model is biologically inspired and reproduces the main BG structures and pathways, modeling explicitly both the dopaminergic and the cholinergic system. The present work aims at interfacing this neurocomputational model with a compartmental model of levodopa, to propose a general model of medicated Parkinson's disease. Levodopa effect on the striatum was simulated with a two-compartment model of pharmacokinetics in plasma joined with a motor effect compartment. The latter is characterized by the levodopa removal rate and by a sigmoidal relationship (Hill law) between concentration and effect. The main parameters of this relationship are saturation, steepness, and the half-maximum concentration. The effect of levodopa is then summed to a term representing the endogenous dopamine effect, and is used as an external input for the neurocomputation model; this allows both the temporal aspects of medication and the individual patient characteristics to be simulated. The frequency of alternate tapping is then used as the outcome of the whole model, to simulate effective clinical scores. Pharmacokinetic-pharmacodynamic modeling was preliminary performed on data of six patients with Parkinson's disease (both "stable" and "wearing-off" responders) after levodopa standardized oral dosing over 4 h. Results show that the model is able to reproduce the temporal profiles of levodopa in plasma and the finger tapping frequency in all patients, discriminating between different patterns of levodopa motor response. The more influential parameters are the Hill coefficient, related with the slope of the effect sigmoidal

  6. A clinico-radiological phenotype of voltage-gated potassium channel complex antibody-mediated disorder presenting with seizures and basal ganglia changes.

    Science.gov (United States)

    Hacohen, Yael; Wright, Sukhvir; Siddiqui, Ata; Pandya, Nikki; Lin, Jean-Pierre; Vincent, Angela; Lim, Ming

    2012-12-01

    In childhood, central nervous system (CNS) presentations associated with antibodies to voltage-gated potassium channel (VGKC) complex include limbic encephalitis, status epilepticus, epileptic encephalopathy, and autistic regression. We report the cases of two individuals (a 6-year-old male and an 11-year-old female) who presented with an acute-onset explosive seizure disorder with positive VGKC complex antibodies and bilateral basal ganglia changes on magnetic resonance imaging (MRI). Both patients made a complete clinical recovery, without immunotherapy, with resolution of the MRI changes and normalization of the antibody levels. Extended antibody testing, including testing for leucine-rich glioma-inactivated 1 (LGI1), contactin-associated protein 2, and contactin-2 was negative. This could suggest that the clinico-radiological phenotype in our patients may in fact be associated with a novel autoreactive target(s) within the VGKC complex, as may be the case in other children with VGKC complex-mediated CNS disorders.

  7. Believer-Skeptic Meets Actor-Critic: Rethinking the Role of Basal Ganglia Pathways during Decision-Making and Reinforcement Learning.

    Science.gov (United States)

    Dunovan, Kyle; Verstynen, Timothy

    2016-01-01

    The flexibility of behavioral control is a testament to the brain's capacity for dynamically resolving uncertainty during goal-directed actions. This ability to select actions and learn from immediate feedback is driven by the dynamics of basal ganglia (BG) pathways. A growing body of empirical evidence conflicts with the traditional view that these pathways act as independent levers for facilitating (i.e., direct pathway) or suppressing (i.e., indirect pathway) motor output, suggesting instead that they engage in a dynamic competition during action decisions that computationally captures action uncertainty. Here we discuss the utility of encoding action uncertainty as a dynamic competition between opposing control pathways and provide evidence that this simple mechanism may have powerful implications for bridging neurocomputational theories of decision making and reinforcement learning. PMID:27047328

  8. Believer-Skeptic meets Actor-Critic: Rethinking the role of basal ganglia pathways during decision-making and reinforcement learning

    Directory of Open Access Journals (Sweden)

    Kyle eDunovan

    2016-03-01

    Full Text Available The flexibility of behavioral control is a testament to the brain’s capacity for dynamically resolving uncertainty during goal-directed actions. This ability to select actions and learn from immediate feedback is driven by the dynamics of basal ganglia (BG pathways. A growing body of empirical evidence conflicts with the traditional view that these pathways act as independent levers for facilitating (i.e., direct pathway or suppressing (i.e., indirect pathway motor output, suggesting instead that they engage in a dynamic competition during action decisions that computationally captures action uncertainty. Here we discuss the utility of encoding action uncertainty as a dynamic competition between opposing control pathways and provide evidence that this simple mechanism may have powerful implications for bridging neurocomputational theories of decision making and reinforcement learning.

  9. Large germinoma in basal ganglia treated by intraarterial chemotherapy with ACNU following osmotic blood-brain barrier disruption and radiation therapy

    Energy Technology Data Exchange (ETDEWEB)

    Miyagami, Mitsusuke; Tsubokawa, Takashi; Kobayashi, Makio.

    1988-10-01

    A rare case of large germinoma in the basal ganglia is reported which was effectively treated by intracarotid chemotherapy with ACNU following osmotic blood-brain barrier disruption using 20 % mannitol and radiation therapy. A 19-year-old man displayed slowly progressive right hemiparesis, motor aphasia and predementia on admission. Plain CT demonstrated a tumor which had a slightly high density with intratumoral calcification and a small cyst, and slight to moderate enhancement was observed following intravenous injection of contrast medium, but there was no unilateral ventricular enlargement. Cerebral angiography revealed hypervascular tumor staining with early draining veins. After biopsy, and as a result of intracarotid chemotherapy with ACNU following osmotic blood-brain barrier disruption and radiation therapy, the tumor decreased rapidly to about 20 % of its original mass. After discharge, tumor progression was observed. However, the enlarged tumor mass almost disappeared (except for calcification) on CT with clinical improvement in response to intracarotid chemotherapy with ACNU following 20 % mannitol.

  10. Believer-Skeptic Meets Actor-Critic: Rethinking the Role of Basal Ganglia Pathways during Decision-Making and Reinforcement Learning

    Science.gov (United States)

    Dunovan, Kyle; Verstynen, Timothy

    2016-01-01

    The flexibility of behavioral control is a testament to the brain's capacity for dynamically resolving uncertainty during goal-directed actions. This ability to select actions and learn from immediate feedback is driven by the dynamics of basal ganglia (BG) pathways. A growing body of empirical evidence conflicts with the traditional view that these pathways act as independent levers for facilitating (i.e., direct pathway) or suppressing (i.e., indirect pathway) motor output, suggesting instead that they engage in a dynamic competition during action decisions that computationally captures action uncertainty. Here we discuss the utility of encoding action uncertainty as a dynamic competition between opposing control pathways and provide evidence that this simple mechanism may have powerful implications for bridging neurocomputational theories of decision making and reinforcement learning. PMID:27047328

  11. Adult-onset Alexander disease with typical "tadpole" brainstem atrophy and unusual bilateral basal ganglia involvement: a case report and review of the literature

    Directory of Open Access Journals (Sweden)

    Sakoe Kumi

    2010-04-01

    Full Text Available Abstract Background Alexander disease (ALX is a rare neurological disorder characterized by white matter degeneration and cytoplasmic inclusions in astrocytes called Rosenthal fibers, labeled by antibodies against glial fibrillary acidic protein (GFAP. Three subtypes are distinguished according to age at onset: infantile (under age 2, juvenile (age 2 to 12 and adult (over age 12. Following the identification of heterozygous mutations in GFAP that cause this disease, cases of adult-onset ALX have been increasingly reported. Case Presentation We present a 60-year-old Japanese man with an unremarkable past and no family history of ALX. After head trauma in a traffic accident at the age of 46, his character changed, and dementia and dysarthria developed, but he remained independent. Spastic paresis and dysphagia were observed at age 57 and 59, respectively, and worsened progressively. Neurological examination at the age of 60 revealed dementia, pseudobulbar palsy, left-side predominant spastic tetraparesis, axial rigidity, bradykinesia and gaze-evoked nystagmus. Brain MRI showed tadpole-like atrophy of the brainstem, caused by marked atrophy of the medulla oblongata, cervical spinal cord and midbrain tegmentum, with an intact pontine base. Analysis of the GFAP gene revealed a heterozygous missense mutation, c.827G>T, p.R276L, which was already shown to be pathogenic in a case of pathologically proven hereditary adult-onset ALX. Conclusion The typical tadpole-like appearance of the brainstem is strongly suggestive of adult-onset ALX, and should lead to a genetic investigation of the GFAP gene. The unusual feature of this patient is the symmetrical involvement of the basal ganglia, which is rarely observed in the adult form of the disease. More patients must be examined to confirm, clinically and neuroradiologically, extrapyramidal involvement of the basal ganglia in adult-onset ALX.

  12. Rapid feedback processing in human nucleus accumbens and motor thalamus.

    Science.gov (United States)

    Schüller, Thomas; Gruendler, Theo O J; Jocham, Gerhard; Klein, Tilmann A; Timmermann, Lars; Visser-Vandewalle, Veerle; Kuhn, Jens; Ullsperger, Markus

    2015-04-01

    The nucleus accumbens (NAcc) and thalamus are integral parts in models of feedback processing. Deep brain stimulation (DBS) has been successfully employed to alleviate symptoms of psychiatric conditions including obsessive-compulsive disorder (OCD) and Tourette's syndrome (TS). Common target structures are the NAcc and the ventral anterior and ventro-lateral nuclei (VA/VL) of the thalamus, for OCD and TS, respectively. The feedback related negativity (FRN) is an event-related potential associated with feedback processing reflecting posterior medial frontal cortex (pMFC) activity. Here we report on three cases where we recorded scalp EEG and local field potentials (LFP) from externalized electrodes located in the NAcc or thalamus (VA/VL) while patients engaged in a modified time estimation task, known to engage feedback processing and elicit the FRN. Additionally, scalp EEG were recorded from 29 healthy participants (HP) engaged in the same task. The signal in all structures (pMFC, NAcc, and thalamus) was differently modulated by positive and negative feedback. LFP activity in the NAcc showed a biphasic time course after positive feedback during the FRN time interval. Negative feedback elicited a much weaker and later response. In the thalamus a monophasic modulation was recorded during the FRN time interval. Again, this modulation was more pronounced after positive performance feedback compared to negative feedback. In channels outside the target area no modulation was observed. The surface-FRN was reliably elicited on a group level in HP and showed no significant difference following negative feedback between patients and HP. German Clinical Trial Register: Neurocognitive specification of dysfunctions within basal ganglia-cortex loops and their therapeutic modulation by deep brain stimulation in patients with obsessive compulsive disorder and Tourette syndrome, http://www.drks.de/DRKS00005316. PMID:25726897

  13. Unusual acute encephalitis involving the thalamus: imaging features

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    Kim, Sam Soo [Kangwon National University Hospital, Chuncheon (Korea, Republic of); Chang, Kee Hyun; Kim, Kyung Won; Han Moon Hee [Seoul National University College of Medicine, Seoul (Korea, Republic of); Park, Sung Ho; Nam, Hyun Woo [Seoul City Boramae Hospital, Seoul (Korea, Republic of); Choi, Kyu Ho [Kangnam St. Mary' s Hospital, Seoul (Korea, Republic of); Cho, Woo Ho [Sanggyo Paik Hospital, Seoul (Korea, Republic of)

    2001-06-01

    To describe the brain CT and MR imaging findings of unusual acute encephalitis involving the thalamus. We retrospectively reviewed the medical records and CT and/or MR imaging findings of six patients with acute encephalitis involving the thalamus. CT (n=6) and MR imaging (n=6) were performed during the acute and/or convalescent stage of the illness. Brain CT showed brain swelling (n=2), low attenuation of both thalami (n=1) or normal findings (n=3). Initial MR imaging indicated that in all patients the thalamus was involved either bilaterally (n=5) or unilaterally (n=1). Lesions were also present in the midbrain (n=5), medial temporal lobe (n=4), pons (n=3), both hippocampi (n=3) the insular cortex (n=2), medulla (n=2), lateral temporal lobe cortex (n=1), both cingulate gyri (n=1), both basal ganglia (n=1), and the left hemispheric cortex (n=1). These CT or MR imaging findings of acute encephalitis of unknown etiology were similar to a combination of those of Japanese encephalitis and herpes simplex encephalitis. In order to document the specific causative agents which lead to the appearance of these imaging features, further investigation is required.

  14. 基底节缺血性卒中对认知功能的影响%A study on cognitive function after ischemic basal ganglia's stroke

    Institute of Scientific and Technical Information of China (English)

    王久武; 孙月吉; 庞鑫鑫; 林媛; 于亮; 李倩; 婉思莹; 周世煜; 郇明明

    2009-01-01

    目的 探讨基底节缺血性卒中导致的认知功能损害特点.方法 基底节缺血性卒中住院患者46例为观察组,所有病例均符1995年10月中华医学会第四届脑血管病学术研讨会通过的脑卒中诊断标准;对照组为性别、年龄和教育程度与观察组相匹配的健康人46例.认知评价采用一般问卷、韦氏成人智力量表的词汇及数字符号测试、韦氏记忆量表、工作记忆课题及威斯康星卡片等,共收集了20项认知功能相关指标.结果 观察组的连线作业A[(54.04±5.66)分]、执行完成分类数[(3.56±0.12)分]、执行错误应答数[(16.17±0.58)分]、执行非持续性错误数[(10.17±0.58)分]的得分显著高于对照组(t=4.67,5.03,9.45,9.5;P0,P<0.05),与顺背与倒背呈负相关(r=-0.857,-0.811;P=0.014,0.027);左侧基底节缺血性卒中体积与词汇测试、经历、视觉再认呈负相关(r=-0.764,-0.907,-0.747;P=0.027,0.002,0.033);右侧基底节缺血性卒中体积与词汇测试、数字符号、视觉再生、执行完成分类数呈负相关(r=-0.747,-0.770,-0.798;P=0.033,0.026,0.011).结论 基底节缺血性卒中可以引起言语智能、执行功能及记忆等认知功能改变,两侧基底节在操作智能、长时记忆及执行功能方面发挥作用不同,基底节卒中体积越大,认知功能损害越明显.%Objective To find the correlation factors of cognitive disorder after ischemic basal ganglia's stroke. Methods 46 cases of ischemic basal ganglia's stroked patients by MRI. And 46 cases health control were tested by Wechsler Adult Intelligence Scale (WAIS),Wechsler Memory Scale (WMS),Trail Making Test A and B,Wisconsin Card Sorting Test (WCST).t test,chi-square,two independent samples and spearmancorrelation were used to analyze the data. Results 1)Group of thalamic stroke compare with health control for recognition index,there were significant different between the two groups,there were higher score in the stroke group at

  15. Neurochemical organization of the human basal ganglia: anatomofunctional territories defined by the distributions of calcium-binding proteins and SMI-32.

    Science.gov (United States)

    Morel, Anne; Loup, Fabienne; Magnin, Michel; Jeanmonod, Daniel

    2002-01-28

    The distribution of the calcium-binding proteins calbindin-D28K (CB), parvalbumin (PV) and calretinin (CR), and of the nonphosphorylated neurofilament protein (with SMI-32) was investigated in the human basal ganglia to identify anatomofunctional territories. In the striatum, gradients of neuropil immunostaining define four major territories: The first (T1) includes all but the rostroventral half of the putamen and is characterized by enhanced matriceal PV and SMI-32 immunoreactivity (-ir). The second territory (T2) encompasses most part of the caudate nucleus (Cd) and rostral putamen (PuT), which show enhanced matriceal CB-ir. The third and fourth territories (T3 and T4) comprise rostroventral parts of Cd and PuT characterized by complementary patch/matrix distributions of CB- and CR-ir, and the accumbens nucleus (Acb), respectively. The latter is separated into lateral (prominently enhanced in CB-ir) and medial (prominently enhanced in CR-ir) subdivisions. In the pallidum, parallel gradients also delimit four territories, T1 in the caudal half of external (GPe) and internal (GPi) divisions, characterized by enhanced PV- and SMI-32-ir; T2 in their rostral half, characterized by enhanced CB-ir; and T3 and T4 in their rostroventral pole and in the subpallidal area, respectively, both expressing CB- and CR-ir but with different intensities. The subthalamic nucleus (STh) shows contrasting patterns of dense PV-ir (sparing only the most medial part) and low CB-ir. Expression of CR-ir is relatively low, except in the medial, low PV-ir, part of the nucleus, whereas SMI-32-ir is moderate across the whole nucleus. The substantia nigra is characterized by complementary patterns of high neuropil CB- and SMI-32-ir in pars reticulata (SNr) and high CR-ir in pars compacta (SNc) and in the ventral tegmental area (VTA). The compartmentalization of calcium-binding proteins and SMI-32 in the human basal ganglia, in particular in the striatum and pallidum, delimits anatomofunctional

  16. Brain MR imaging in patients with hepatic cirrhosis: relationship between high intensity signal in basal ganglia on T{sub 1}-weighted images and elemental concentrations in brain

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, H. [Department of Radiology, Wakayama Medical College, 27-7, Wakayama City, 640 (Japan); Sato, M. [Department of Radiology, Wakayama Medical College, 27-7, Wakayama City, 640 (Japan); Yoshikawa, A. [Department of Radiology, Wakayama Medical College, 27-7, Wakayama City, 640 (Japan); Kimura, M. [Department of Radiology, Wakayama Medical College, 27-7, Wakayama City, 640 (Japan); Sonomura, T. [Department of Radiology, Wakayama Medical College, 27-7, Wakayama City, 640 (Japan); Terada, M. [Department of Radiology, Wakayama Medical College, 27-7, Wakayama City, 640 (Japan); Kishi, K. [Department of Radiology, Wakayama Medical College, 27-7, Wakayama City, 640 (Japan)

    1997-08-01

    In patients with hepatic cirrhosis, the globus pallidus and putamen show high intensity on T1-weighted MRI. While the causes of this high signal have been thought to include paramagnetic substances, especially manganese, no evidence for this has been presented. Autopsy in four cases of hepatic cirrhosis permitted measurement of metal concentrations in brain and histopathological examination. In three cases the globus pallidus showed high intensity on T1-weighted images. Mean manganese concentrations in globus pallidus, putamen and frontal white matter were 3.03 {+-} 0.38, 2.12 {+-} 0.37, and 1.38 {+-} 0.24 ({mu}g/g wet weight), respectively, being approximately four- to almost ten-fold the normal values. Copper concentrations in globus pallidus and putamen were also high, 50 % more than normal. Calcium, iron, zinc and magnesium concentrations were all normal. The fourth case showed no abnormal intensity in the basal ganglia and brain metal concentrations were all normal. Histopathologically, cases with showing high signal remarkable atrophy, necrosis, and deciduation of nerve cells and proliferation of glial cells and microglia in globus pallidus. These findings were similar to those in chronic manganese poisoning. On T1-weighted images, copper deposition shows no abnormal intensity. It is therefore inferred that deposition of highly concentrations of manganese may caused high signal on T1-weighted images and nerve cell death in the globus pallidus. (orig.). With 2 figs., 2 tabs.

  17. Alteration of basal ganglia and right frontoparietal network in early drug-naïve Parkinson’s disease during heat pain stimuli and resting state

    Directory of Open Access Journals (Sweden)

    Ying eTan

    2015-08-01

    Full Text Available Background: The symptoms and pathogenesis of Parkinson’s disease (PD are complicated and accurate diagnosis is difficult, particularly in early-stage. Functional magnetic resonance imaging is noninvasive and characterized by the integration of different brain areas at functional connectivity (FC. Considering pain process in PD, we hypothesized that pain is one of the earliest symptoms and investigated whether FC of the pain network was disrupted in PD without pain.Methods: Fourteen early drug-naïve PD without pain and 17 age- and sex-matched healthy controls (HC participated in our test. We investigate abnormalities in FC and in functional network connectivity in PD compared with HC during the task (51 °C heat pain stimuli and at rest.Results: Compared with HC, PD showed decreased FC in basal ganglia network (BGN, salience network (SN and sensorimotor network in two states respectively. FNC between the BGN and the SN are reduced during both states in PD compared with HC. In addition, the FNC associated with right frontoparietal network (RFPN was also significantly disturbed during the task.Conclusion: These findings suggest that BGN plays a role in the pathological mechanisms of pain underlying PD, and RFPN likely contributes greatly to harmonization between intrinsic brain activity and external stimuli.

  18. AN EXTENDED REINFORCEMENT LEARNING MODEL OF BASAL GANGLIA TO UNDERSTAND THE CONTRIBUTIONS OF SEROTONIN AND DOPAMINE IN RISK-BASED DECISION MAKING, REWARD PREDICTION, AND PUNISHMENT LEARNING

    Directory of Open Access Journals (Sweden)

    Pragathi Priyadharsini Balasubramani

    2014-04-01

    Full Text Available Although empirical and neural studies show that serotonin (5HT plays many functional roles in the brain, prior computational models mostly focus on its role in behavioral inhibition. In this study, we present a model of risk based decision making in a modified Reinforcement Learning (RL-framework. The model depicts the roles of dopamine (DA and serotonin (5HT in Basal Ganglia (BG. In this model, the DA signal is represented by the temporal difference error (δ, while the 5HT signal is represented by a parameter (α that controls risk prediction error. This formulation that accommodates both 5HT and DA reconciles some of the diverse roles of 5HT particularly in connection with the BG system. We apply the model to different experimental paradigms used to study the role of 5HT: 1 Risk-sensitive decision making, where 5HT controls risk assessment, 2 Temporal reward prediction, where 5HT controls time-scale of reward prediction, and 3 Reward/Punishment sensitivity, in which the punishment prediction error depends on 5HT levels. Thus the proposed integrated RL model reconciles several existing theories of 5HT and DA in the BG.

  19. An extended reinforcement learning model of basal ganglia to understand the contributions of serotonin and dopamine in risk-based decision making, reward prediction, and punishment learning.

    Science.gov (United States)

    Balasubramani, Pragathi P; Chakravarthy, V Srinivasa; Ravindran, Balaraman; Moustafa, Ahmed A

    2014-01-01

    Although empirical and neural studies show that serotonin (5HT) plays many functional roles in the brain, prior computational models mostly focus on its role in behavioral inhibition. In this study, we present a model of risk based decision making in a modified Reinforcement Learning (RL)-framework. The model depicts the roles of dopamine (DA) and serotonin (5HT) in Basal Ganglia (BG). In this model, the DA signal is represented by the temporal difference error (δ), while the 5HT signal is represented by a parameter (α) that controls risk prediction error. This formulation that accommodates both 5HT and DA reconciles some of the diverse roles of 5HT particularly in connection with the BG system. We apply the model to different experimental paradigms used to study the role of 5HT: (1) Risk-sensitive decision making, where 5HT controls risk assessment, (2) Temporal reward prediction, where 5HT controls time-scale of reward prediction, and (3) Reward/Punishment sensitivity, in which the punishment prediction error depends on 5HT levels. Thus the proposed integrated RL model reconciles several existing theories of 5HT and DA in the BG.

  20. Dopamine transporter density in the basal ganglia assessed with {sup 123}I-IPT SPECT in children with attention deficit hyperactivity disorder

    Energy Technology Data Exchange (ETDEWEB)

    Yoo, Y. H.; Cheon, K. A.; Yoon, M. J.; Kim, C. H.; Lee, J. D. [Yonsei University College of Medicine, Seoul (Korea, Republic of); Kim, H. H.; Choi, T. H. [Gachon Medical School, Incheon (Korea, Republic of)

    2002-07-01

    Attention deficit hyperactivity disorder (ADHD) is known as a psychiatric disorder in childhood associated with dopamine dysregulation. We investigated dopamine transporter (DAT) density in children with ADHD in the present study using {sup 123}I-IPT SPECT and postulated that an alteration in DAT density in the basal ganglia (BG) is responsible for dopaminergic dysfunction in children with ADHD. 9 durg-naive children with ADHD and 6 normal children were included in the study. We performed brain SPECT 2 hours after administration of {sup 123}I-IPT and made both quantitative and qualitative analyses for assessment of specific/nonspecific DAT binding ratio in the BG. We investigated the correlation between the severity scores of ADHD symptoms in children with ADHD assessed with ADHD rating scale and specific/nonspecific DAT binding ratio in the BG. Drug-naive children with ADHD showed a significantly incresed specific/nonspecific DAT binding ratio in the BG compared with normal children. Whereas, no significant correlation was found between severity scores of symptoms in children with ADHD and specific/nonspecific DAT binding ratio n the BG. Our findings support complex dysregulation of the dopaminergic neurotransmitter system in children with ADHD.

  1. Basal ganglia stroke due to mild head trauma in pediatric age - clinical and therapeutic management: a case report and 10 year literature review.

    Science.gov (United States)

    Landi, Alessandro; Marotta, Nicola; Mancarella, Cristina; Marruzzo, Daniele; Salvati, Maurizio; Delfini, Roberto

    2011-01-06

    Ischemia of the basal ganglia as an immediate consequence of minor head injury in children is rare (< 2% of all ischemic stroke in childhood) and is due to vasospasm of the lenticulostriate arteries. The clinical history of these lesions is particularly favourable because they are usually small, and also because the facial-brachial-crural hemiparesis typical of this pathology usually regresses after a period ranging from several weeks to several months, despite the persistence of an ischemic area on MRI. This is due to the well known neuronal plasticity of the CNS, in particular, of the primary motor cortex. The most effective therapeutic approach appears to be the conservative one, although the best treatment regimen is still not well defined.Young patients should be closely monitored and treated conservatively with osmotic diuretics to reduce perilesional edema. At the same time, however, it is very important to exclude, by means of instrumental and laboratory studies, conditions that could favour the onset of ischemia, including emboligen heart disease, thrombophilia and acute traumatic arterial dissections. Generally speaking, the prognosis in these cases is good. The authors describe their experience treating a 10-month old baby girl, with a left lenticular nucleus ischemia and report a literature review.

  2. [Hypomyelination with atrophy of the basal ganglia and cerebellum. Contribution of two new cases to a recently reported entity].

    Science.gov (United States)

    Tomás-Vila, Miguel; Menor, Francisco; Ley-Martos, Myriam; Jumillas-Luján, M José; Marco-Hernández, Ana V; Barbero, Pedro

    2014-02-16

    Introduccion. La hipomielinizacion con atrofia de ganglios basales y de cerebelo (H-ABC) es una rara entidad descrita recientemente. Se presentan dos nuevos casos pertenecientes a una misma familia. Casos clinicos. Caso 1: niño de 17 meses con retraso grave en todas las areas, ausencia de lenguaje y de contacto visual. En la exploracion destacaba una microcefalia con tetraparesia espastica. En la resonancia magnetica cerebral se apreciaba atrofia cerebelosa de predominio vermiano con perdida de volumen de ambos nucleos del putamen y la cabeza del caudado, y patron de hipomielinizacion de la sustancia blanca. En la electromiografia se objetivo un patron de polineuropatia cronica de predominio motor. Presento un descenso de los valores de acido homovalinico y de acido 5-hidroxindolacetico. El tratamiento con levodopa/carbidopa no fue efectivo. Caso 2: niña de 11 meses, hermana del caso anterior. Presentaba un retraso grave en todas las areas y en la exploracion clinica se detecto una microcefalia con tetraparesia espastica. La resonancia magnetica cerebral mostro hallazgos superponibles a los del hermano, con hipomielinizacion, atrofia cerebelosa y afectacion putaminal y de ambos caudados; en la electromiografia, hallazgos compatibles con polineuropatia motora de caracter desmielinizante. Presento un descenso de los valores de acido homovalinico y acido 5-hidroxindolacetico en el liquido cefalorraquideo. El tratamiento con levodopa/carbidopa resulto ineficaz. Conclusiones. Estos dos nuevos casos ayudan a caracterizar mejor esta entidad y refuerzan la hipotesis del origen genetico del sindrome, dado que se trata de dos casos pertenecientes a una misma familia.

  3. Characterization and distribution of [125I]epidepride binding to dopamine D2 receptors in basal ganglia and cortex of human brain

    International Nuclear Information System (INIS)

    The distribution and pharmacology of the binding of 125I-epidepride, a substituted benzamide with high affinity and selectivity for dopamine (DA) D2 receptors in rat brain is described in human brain. Saturation analysis of the binding of 125I-epidepride to membranes derived from striatum and regions of cortex demonstrated similar Kd values (34 and 28-33 pM, respectively) but differing maximum density of binding site values (152 and 3-8 fmol/mg of protein, respectively). The pharmacological profile of binding in cortex was also similar to striatum (epidepride greater than spiperone greater than butaclamol = flupenthixol greater than clozapine) except that an additional low-affinity site, blocked by the alpha-2 adrenergic antagonist idazoxan, was present in cortex. Quantification by autoradiography also demonstrated the greatest binding in the basal ganglia, with the striatum exhibiting greater binding than the pallidal complex or midbrain regions. For the pallidum, binding in the external segment was higher than the internal segment. Within the midbrain the binding of 125I-epidepride correlated well with the known distribution of DA-containing cell bodies, with the substantia nigra (pars compacta and pars lateralis) and ventral tegmental area (A10) higher than area A8 and central gray. Binding in frontal and parietal cortex was highest in the internal layers (layers V and VI). Temporal cortex showed a 2-fold higher density of binding than other cortical regions and a trilaminar pattern; binding was greater in the external (layers I and II) and internal layers than in the middle layers (III and IV). This pattern changed in the parahippocampal complex. Within the lateral occipitotemporal cortex, binding was densest in layers I to III and very low in layers IV to VI, but binding was almost nonexistent in the adjacent entorhinal cortex

  4. Characterization and distribution of (125I)epidepride binding to dopamine D2 receptors in basal ganglia and cortex of human brain

    Energy Technology Data Exchange (ETDEWEB)

    Joyce, J.N.; Janowsky, A.; Neve, K.A. (Department of Psychiatry, University of Pennsylvania School of Medicine, Philadelphia (USA))

    1991-06-01

    The distribution and pharmacology of the binding of {sup 125}I-epidepride, a substituted benzamide with high affinity and selectivity for dopamine (DA) D2 receptors in rat brain is described in human brain. Saturation analysis of the binding of {sup 125}I-epidepride to membranes derived from striatum and regions of cortex demonstrated similar Kd values (34 and 28-33 pM, respectively) but differing maximum density of binding site values (152 and 3-8 fmol/mg of protein, respectively). The pharmacological profile of binding in cortex was also similar to striatum (epidepride greater than spiperone greater than butaclamol = flupenthixol greater than clozapine) except that an additional low-affinity site, blocked by the alpha-2 adrenergic antagonist idazoxan, was present in cortex. Quantification by autoradiography also demonstrated the greatest binding in the basal ganglia, with the striatum exhibiting greater binding than the pallidal complex or midbrain regions. For the pallidum, binding in the external segment was higher than the internal segment. Within the midbrain the binding of {sup 125}I-epidepride correlated well with the known distribution of DA-containing cell bodies, with the substantia nigra (pars compacta and pars lateralis) and ventral tegmental area (A10) higher than area A8 and central gray. Binding in frontal and parietal cortex was highest in the internal layers (layers V and VI). Temporal cortex showed a 2-fold higher density of binding than other cortical regions and a trilaminar pattern; binding was greater in the external (layers I and II) and internal layers than in the middle layers (III and IV). This pattern changed in the parahippocampal complex. Within the lateral occipitotemporal cortex, binding was densest in layers I to III and very low in layers IV to VI, but binding was almost nonexistent in the adjacent entorhinal cortex.

  5. Human-specific increase of dopaminergic innervation in a striatal region associated with speech and language: A comparative analysis of the primate basal ganglia.

    Science.gov (United States)

    Raghanti, Mary Ann; Edler, Melissa K; Stephenson, Alexa R; Wilson, Lakaléa J; Hopkins, William D; Ely, John J; Erwin, Joseph M; Jacobs, Bob; Hof, Patrick R; Sherwood, Chet C

    2016-07-01

    The dopaminergic innervation of the striatum has been implicated in learning processes and in the development of human speech and language. Several lines of evidence suggest that evolutionary changes in dopaminergic afferents of the striatum may be associated with uniquely human cognitive and behavioral abilities, including the association of the human-specific sequence of the FOXP2 gene with decreased dopamine in the dorsomedial striatum of mice. To examine this possibility, we quantified the density of tyrosine hydroxylase-immunoreactive axons as a measure of dopaminergic innervation within five basal ganglia regions in humans, great apes, and New and Old World monkeys. Our results indicate that humans differ from nonhuman primate species in having a significant increase in dopaminergic innervation selectively localized to the medial caudate nucleus. This region of the striatum is highly interconnected, receiving afferents from multiple neocortical regions, and supports behavioral and cognitive flexibility. The medial caudate nucleus also shows hyperactivity in humans lacking a functional FOXP2 allele and exhibits altered dopamine concentrations in humanized Foxp2 mice. Additionally, striatal dopaminergic input was not altered in chimpanzees that used socially learned attention-getting sounds versus those that did not. This evidence indicates that the increase in dopamine innervation of the medial caudate nucleus in humans is a species-typical characteristic not associated with experience-dependent plasticity. The specificity of this increase may be related to the degree of convergence from cortical areas within this region of the striatum and may also be involved in human speech and language. J. Comp. Neurol. 524:2117-2129, 2016. © 2015 Wiley Periodicals, Inc. PMID:26715195

  6. Can minimal invasive puncture and drainage for hypertension spontaneous basal ganglia intracerebral hemorrhage improve patient outcome: A prospective non-randomized comparative study

    Directory of Open Access Journals (Sweden)

    Guo-qiang WANG

    2014-08-01

    Full Text Available Objective The treatment of hypertensive spontaneous intracranial hemorrhage (ICH is still controversial. The purpose of the present study was to investigate whether minimally invasive puncture and drainage (MIPD could provide improved patient outcome compared with decompressive craniectomy (DC. Methods Eligible, consecutive patients with ICH (≥30 ml, in basal ganglia, within 24 hours of ictus were non-randomly assigned to receive MIPD (group A or to undergo DC (group B hematoma evacuation. The primary outcome was death at 30 days after onset. Functional independence was assessed at 1 year using the Glasgow Outcome Scale (GOS, scores range from 1 to 5, score 1 indicating death, ≥4 indicating functional independence, with lower scores indicating greater disability. Results A total of 198 patients met the per protocol analysis (84 cases in group A and 114 cases in group B, including 9 cases lost during follow-up (2 cases in group A and 7 cases in group B. For these 9 patients, their last observed data were used as their final results for intention-to-treat analysis. The mean age of all patients was 57.1 years (range of 31-95 years, and 144 patients were male. The initial Glasgow Coma Scale (GCS score was 8.1±3.4, and the National Institutes of Health Stroke Scale (NIHSS score was 20.8±5.3. The mean hematoma volume (HV was 56.7±23.0 ml (range of 30-144 ml, and there was extended intraventricular hemorrhage (IVH in 134 patients (67.7%. There were no significant intergroup differences in the above baseline data, except group A had a higher mean age (59.4±14.5 years than the mean age of group B (55.3±11.1 years, P =0.025. The total cumulative mortalities at 30 days and 1 year were 32.3% and 43.4%, respectively, and there were no significant differences between groups A and B (30 days: 27.4% vs 36.0%, P =0.203; 1 year: 36.1% vs 48.2%, P =0.112, respectively. However, the mortality for patients ≤60 years, NIHSS60 ml, deep coma and severe

  7. A network model of basal ganglia for understanding the roles of dopamine and serotonin in reward-punishment-risk based decision making

    Directory of Open Access Journals (Sweden)

    Pragathi Priyadharsini Balasubramani

    2015-06-01

    Full Text Available There is significant evidence that in addition to reward-punishment based decision making, the Basal Ganglia (BG contributes to risk-based decision making as well. Despite this evidence, little is known about the computational principles and neural correlates of risk computation in this subcortical system. We have previously proposed a reinforcement learning based model of the BG that simulates the interactions between dopamine (DA and serotonin (5HT in a diverse set of experimental effects including reward, punishment and risk based decision making. Starting with the idea that the activity of DA represents reward prediction error, the model posits that serotoninergic activity in the striatum controls risk-prediction error. Our prior model of the BG was an abstract model that did not incorporate anatomical and cellular-level data. In this work, we expand the earlier model into a detailed network model of the BG and demonstrate the joint contributions of DA-5HT in risk and reward-punishment sensitivity. At the core of the proposed network model is the following insight regarding cellular correlates of value and risk computation. Just as DA D1 receptor (D1R expressing medium spiny neurons (MSNs of the striatum were thought to be neural substrates for value computation, we propose that DA D1R and D2R co-expressing MSNs, reported to occupy a significant proportion of the striatum and are implicated in disorders like schizophrenia and drug addiction, are capable of computing risk. Ours is the first-of-its-kind model that accounts for the significant computational possibilities of these co-expressing D1R-D2R MSNs, and describes how DA-5HT mediated activity in these classes of neurons (D1R-, D2R-, D1R-D2R- MSNs contribute to the BG dynamics. We also apply the model to capture the behaviour of PD patients in a probabilistic learning paradigm. The study observes that optimizing 5HT levels along with DA medication could be essential to improving the

  8. A network model of basal ganglia for understanding the roles of dopamine and serotonin in reward-punishment-risk based decision making.

    Science.gov (United States)

    Balasubramani, Pragathi P; Chakravarthy, V Srinivasa; Ravindran, Balaraman; Moustafa, Ahmed A

    2015-01-01

    There is significant evidence that in addition to reward-punishment based decision making, the Basal Ganglia (BG) contributes to risk-based decision making (Balasubramani et al., 2014). Despite this evidence, little is known about the computational principles and neural correlates of risk computation in this subcortical system. We have previously proposed a reinforcement learning (RL)-based model of the BG that simulates the interactions between dopamine (DA) and serotonin (5HT) in a diverse set of experimental studies including reward, punishment and risk based decision making (Balasubramani et al., 2014). Starting with the classical idea that the activity of mesencephalic DA represents reward prediction error, the model posits that serotoninergic activity in the striatum controls risk-prediction error. Our prior model of the BG was an abstract model that did not incorporate anatomical and cellular-level data. In this work, we expand the earlier model into a detailed network model of the BG and demonstrate the joint contributions of DA-5HT in risk and reward-punishment sensitivity. At the core of the proposed network model is the following insight regarding cellular correlates of value and risk computation. Just as DA D1 receptor (D1R) expressing medium spiny neurons (MSNs) of the striatum were thought to be the neural substrates for value computation, we propose that DA D1R and D2R co-expressing MSNs are capable of computing risk. Though the existence of MSNs that co-express D1R and D2R are reported by various experimental studies, prior existing computational models did not include them. Ours is the first model that accounts for the computational possibilities of these co-expressing D1R-D2R MSNs, and describes how DA and 5HT mediate activity in these classes of neurons (D1R-, D2R-, D1R-D2R- MSNs). Starting from the assumption that 5HT modulates all MSNs, our study predicts significant modulatory effects of 5HT on D2R and co-expressing D1R-D2R MSNs which in turn

  9. Analysis on Surgery for Hypertensive Cerebral Hemorrhage in Basal Ganglia Regions%基底节区高血压脑出血手术治疗分析

    Institute of Scientific and Technical Information of China (English)

    汤秉洪; 覃宗明; 杨明彬; 陈建刚

    2012-01-01

    Objective To study the surgical timing, method and curative effect of surgery on hypertensive cerebral hemorrhage in basal ganglia regions. Methods We reviewed the clinical data of 168 patients undergoing operation cures for hypertensive cerebral hemorrhage in basal ganglia regions from January 2006 to January 2011. There were 98 males and 70 females with their age ranging from 35 to 84 years old averaging at 65.2 years. The time between onset of the disease and admission to hospital ranged from 0.5 to 48 hours averaging 7.1 hours. At admission, the conscious status was classified as class I in 32 patients, II in 46, III in 41, IV in 28, and V in 21. Head CT examination at admission showed the lateral type in 51 patients, medial type in 71, and mixed type in 46. The volume of hematoma was 25 to 50 mL in 76 patients, 50 to 80 mL in 53, and larger than 80 mL in 39. The small window craniotomy was performed in 127 cases, and lines of bone flap craniotomy was performed in 41 cases. Results Among the 168 patients, 16 died (9.52%). Re-hemorrhage occurred in 8 patients 4 to 28 hours after operation, among whom immediate operation was performed to remove the hematoma in 6 patients, non operation treatment in 2 cases, and 4 patients died. Six patients died of large volume of hematoma or hemiation. Pulmonary or urinary tract infection occurred in 3 patients, and multiple organ failure in 3 patients. According to Glasgow outcome scale (GOS) score at discharge, the outcome was good in 82 patients, moderate disability in 46, severe disability in 16, persistent vegetative in 8, and 16 died. Patients were followed up for 3 to 6 months, and according to the daily work capacity (ADL) classification, there were 33 cases of class I , 49 of class Ⅱ , 54 of class Ⅲ , 8 of class Ⅳ , and 8 of class Ⅴ . Conclusion Ultra early or early operation done under direct vision, clearing hematoma completely, and reliable coagulation of the bleeding arteries responsible for the hematoma

  10. Functional magnetic resonance imaging of basal ganglia. Activation mapping with FLASH sequences for BOLD contrast and high resolution; Funktionelle Magnetresonanztomographie der Basalganglien. Einsatz von FLASH-Sequenzen zum Aktivitaetsmapping mit BOLD-Kontrast und Hochaufloesung

    Energy Technology Data Exchange (ETDEWEB)

    Seelos, K.C. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Univ. Muenchen (Germany); Bucher, S.F. [Neurologische Klinik und Poliklinik, Klinikum Grosshadern, Univ. Muenchen (Germany); Stehling, M.K. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Univ. Muenchen (Germany); Oertel, W.H. [Neurologische Klinik und Poliklinik, Klinikum Grosshadern, Univ. Muenchen (Germany); Reiser, M. [Inst. fuer Radiologische Diagnostik, Klinikum Grosshadern, Univ. Muenchen (Germany)

    1995-04-01

    The activation pattern of putamen, internal and external division of globus pallidus was investigated during rapid pronation and supination of the right and left hand in 12 normal volunteers using a FLASH sequence with high resolution for functional magnetic resonance imaging (fMRI) at 1.5 T. The chosen paradigm for motor function led to a signal increase within the basal ganglia between 3 and 23%, depending on the structure and individual subject. In all cases significant activation could be found contralateral to the moving hand. In six cases activation was also found on the ipsilateral side. The activated areas within putamen, internal and external division of globus pallidus were less than 5 mm{sup 2}. These first results indicate that fMRI studies of basal ganglia are feasible and might be suitable for analyzing basal ganglia disorders. (orig.) [Deutsch] Das Aktivierungsmuster von Putamen, Globus pallidus internus und externus waehrend schneller Pronation und Supination von rechter und linker Hand wurde bei 12 normalen Probanden mit Hilfe einer fuer die funktionelle Magnetresonanztomographie (fMRT) geeigneten hochaufloesenden FLASH-Sequenz bei 1,5 Tesla untersucht. Der durch das Bewegungsparadigma verursachte Signalanstieg innerhalb der Basalganglien lag je nach Struktur und untersuchtem Individuum zwischen 3 und 23%. In allen Faellen war kontralateral zur bewegten Hand ein signifikanter Aktivitaetsanstieg nachweisbar. In 6 Faellen war auch auf der ipsilateralen Seite eine Aktivitaet nachweisbar. Die aktivierten Areale innerhalb von Putamen, Globus pallidus internus und externus waren nicht groesser als 5 mm{sup 2}. Diese ersten Ergebnisse zeigen, dass magnetresonanztomographische Funktionsuntersuchungen im Bereich der Basalganglien moeglich sind und geeignet erscheinen, um Erkrankungen dieser Systeme zu analysieren. (orig.)

  11. Clinlc and lmaging of the hypoxia cerebropathy in bilateral basal ganglia%双侧基底节区缺氧性脑病的临床与影像学特征

    Institute of Scientific and Technical Information of China (English)

    钟望涛; 郑华; 邢永前; 王义刚

    2001-01-01

    目的探讨双侧基底节区缺氧性脑病的临床表现及影像学特点。方法回顾性分析8例经头MRI证实为双侧基底节区缺氧性脑病患者的临床资料及影像学改变。结果8例均以肌张力增高、运动减少、姿势反射异常等帕金森综合征为主要表现,头MRI表现为双侧基底节区的壳核、苍白球、尾状核头部对称性长T1长T2信号改变。结论双侧基底节缺氧性脑病与皮层下型分水岭梗死(CWI)有完全不同的临床表现和影像学改变。%Objective To investigate the aetiology,pathogeny,clinic,and imaging of the hypoxia cerebropathy in bilateral basal ganglia.Methods The clinical features and imaging in 8 cases were analysed retrospectively after confirmed by MRI,with the hypoxia cerebropathy in bilateral basal ganglia.Results The main manifestation of 8 cases were Parkinsonian syndrome including hypertonia,hypomotor,and anomaly of the posture reflex,MRI scan shows the bilateral long T1 long T2 variation signal in putamens,pallidums and caput nuclei caudatis.Conclusion The clinical manifestation and imaging of the hypoxia cerebropathy in bilateral basal ganglia were different from the subcortical watershed infarct.

  12. Disease-specific structural changes in thalamus and dentatorubrothalamic tract in progressive supranuclear palsy

    Energy Technology Data Exchange (ETDEWEB)

    Surova, Yulia; Hall, Sara; Widner, Haakan [Lund University, Department of Clinical Sciences, Lund (Sweden); Skaane University Hospital, Department of Neurology, Lund (Sweden); Nilsson, Markus [Lund University, Lund University Bioimaging Center, Lund (Sweden); Laett, Jimmy [Skaane University Hospital, Center for Medical Imaging and Physiology, Lund (Sweden); Lampinen, Bjoern [Lund University, Department of Medical Radiation Physics, Lund (Sweden); Lindberg, Olof [Malmoe, Lund University, Department of Clinical Sciences, Malmoe (Sweden); Nilsson, Christer [Skaane University Hospital, Department of Neurology, Lund (Sweden); Malmoe, Lund University, Department of Clinical Sciences, Malmoe (Sweden); Westen, Danielle van [Lund University, Department of Clinical Sciences, Lund (Sweden); Skaane University Hospital, Center for Medical Imaging and Physiology, Lund (Sweden); Hansson, Oskar [Malmoe, Lund University, Department of Clinical Sciences, Malmoe (Sweden); Skaane University Hospital, Memory Clinic, Lund (Sweden)

    2015-11-15

    The aim of this study is to identify disease-specific changes of the thalamus, basal ganglia, pons, and midbrain in patients with progressive supranuclear palsy (PSP), Parkinson's disease (PD), and multiple system atrophy with predominant parkinsonism (MSA-P) using diffusion tensor imaging and volumetric analysis. MRI diffusion and volumetric data were acquired in a derivation of 30 controls and 8 patients with PSP and a validation cohort comprised of controls (n = 21) and patients with PSP (n = 27), PD (n = 10), and MSA-P (n = 11). Analysis was performed using regions of interest (ROI), tract-based spatial statistic (TBSS), and tractography and results compared between diagnostic groups. In the derivation cohort, we observed increased mean diffusivity (MD) in the thalamus, superior cerebellar peduncle, and the midbrain in PSP compared to controls. Furthermore, volumetric analysis showed reduced thalamic volumes in PSP. In the validation cohort, the observations of increased MD were replicated by ROI-based analysis and in the thalamus by TBSS-based analysis. Such differences were not found for patients with PD in any of the cohorts. Tractography of the dentatorubrothalamic tract (DRTT) showed increased MD in PSP patients from both cohorts compared to controls and in the validation cohort in PSP compared to PD and MSA patients. Increased MD in the thalamus and along the DRTT correlated with disease stage and motor function in PSP. Patients with PSP, but not PD or MSA-P, exhibit signs of structural abnormalities in the thalamus and in the DRTT. These changes are associated with disease stage and impaired motor function. (orig.)

  13. Disease-specific structural changes in thalamus and dentatorubrothalamic tract in progressive supranuclear palsy

    International Nuclear Information System (INIS)

    The aim of this study is to identify disease-specific changes of the thalamus, basal ganglia, pons, and midbrain in patients with progressive supranuclear palsy (PSP), Parkinson's disease (PD), and multiple system atrophy with predominant parkinsonism (MSA-P) using diffusion tensor imaging and volumetric analysis. MRI diffusion and volumetric data were acquired in a derivation of 30 controls and 8 patients with PSP and a validation cohort comprised of controls (n = 21) and patients with PSP (n = 27), PD (n = 10), and MSA-P (n = 11). Analysis was performed using regions of interest (ROI), tract-based spatial statistic (TBSS), and tractography and results compared between diagnostic groups. In the derivation cohort, we observed increased mean diffusivity (MD) in the thalamus, superior cerebellar peduncle, and the midbrain in PSP compared to controls. Furthermore, volumetric analysis showed reduced thalamic volumes in PSP. In the validation cohort, the observations of increased MD were replicated by ROI-based analysis and in the thalamus by TBSS-based analysis. Such differences were not found for patients with PD in any of the cohorts. Tractography of the dentatorubrothalamic tract (DRTT) showed increased MD in PSP patients from both cohorts compared to controls and in the validation cohort in PSP compared to PD and MSA patients. Increased MD in the thalamus and along the DRTT correlated with disease stage and motor function in PSP. Patients with PSP, but not PD or MSA-P, exhibit signs of structural abnormalities in the thalamus and in the DRTT. These changes are associated with disease stage and impaired motor function. (orig.)

  14. 肝豆状核变性患者中文书写时皮质下结构的功能影像研究%The role of the basal ganglia in processing of Chinese writing: evidence from a PET study in Wilson's disease

    Institute of Scientific and Technical Information of China (English)

    陈东; 刘晓加; 吴湖炳; 梁秀龄; 李洵桦

    2009-01-01

    ObjectiveTo investigate the role of basal ganglia in processing of Chinese writing by Wilson' disease(WD). Methods7 WD patients were divided into two groups which were normal writing group and dysgraphia group. They were scanned by 18F-fluorodeoxyglucose(18F-FDG) positron emission tomography respectively while performing two tasks: 1) pseudo-writing,2) Chinese character writing. Data were analyzed with Statistical Parametric Mapping. ResultsCompared with pseudo-writing,patients in normal writing group showed greater activation of bilateral lateral globus pallidus and right putamen,whereas patients in dysgraphia group showed greater activation of right ventral lateral nucleus,claustrum,left putamen and lateral globus pallidus(P<0.01). Conclusions1) The results indicate that Chinese writing of WD patients involves in bilateral subcortical structure. Right basal ganglia plays more important role. 2) Activated areas in bilateral basal ganglia of WD patients with agraphia are different with WD patients with normal writing and right thalamus play a compensatory role when WD patients with agraphia are writing.%目的 通过观察脑型肝豆状核变性患者中文字词书写的皮质下结构激活特点,为基底神经节在书写中的作用机制提供实验数据.方法 将7例脑型肝豆状核变性患者分成正常书写组和书写障碍组,分别进行假写作业、中文字词书写作业的18氟脱氧葡萄糖(18F-fluorodeoxyglucose,18F-FDG)脑功能成像,用统计参数图软件(SPM2)得出基底神经节变化区域.结果 正常书写组的皮质下结构激活区包括双侧苍白球和右侧壳核,书写障碍组包括右侧丘脑腹外侧核、屏状核和左侧壳核、苍白球,均差异有显著性(P<0.01).结论 1)脑型肝豆状核变性患者的中文书写涉及双侧基底神经节,右侧基底神经节可能发挥更重要的作用.2)伴有书写障碍的肝豆状核变性患者双侧基底神经节激活点与正常书写的患

  15. 经外侧裂岛叶入路显微清除高血压性基底节区脑出血%Transsylvian-transinsular approach for the microsurgical removal of hypertensive basal ganglia hemorrhage

    Institute of Scientific and Technical Information of China (English)

    刘永; 张玉海; 何升学; 赵金兵; 朱海涛; 张光绪; 邹元杰

    2015-01-01

    目的:探讨在显微镜下经外侧裂-岛叶入路清除高血压性基底节区脑出血的手术要点及脑组织和血管保护。方法回顾性分析18例经外侧裂-岛叶入路显微手术清除基底节区高血压脑出血患者临床资料。术后复查头颅CT了解血肿清除情况。采用Karnofsky功能状态评分评估术后3~6个月患者功能状态。结果本组血肿清除>90%16例,80%~90%1例;再出血1例。其中1例患者因术后严重肺部感染死亡。随访3~6个月,KPS 90~100分3例,60~80分9例,30~50分4例,10~20分1例。结论经外侧裂-岛叶入路有利于保护重要的大脑皮层和血管,是显微清除高血压性基底节区脑出血安全有效的手术方式。%Objective To explore the key points of transsylvian-transinsular approach to remove the hypertensive basal ganglia hemorrhage and adjacent brain tissue and blood vessels protection . Methods The clinical data of 18 patients who underwent the transsylvian-transinsular approach to remove the hypertensive basal ganglia hemorrhage were analyzed retrospectively .The volume of remaining hematoma was evaluated by postoperative CT scan .The Karnofsky performance score was used to evaluated patient outcome of 3-6 months after the surgery .Results The evacuation rate of hematoma was >90% in 16 patients and 80%-90% in 1.One case occured rehemorrhage .One patient died from severe pulmonary infection .The follow-up from 3 to 6 months showed KPS was 90~100 in 3 patients,60~80 in 9,30 ~50 in 4 and 10 ~20 in 1.Conclusion The transsylvian-transinsular approach was benefit to protect important cerebral cortex and vessels ,thus being a safe and effective operation method for microscopic removal of hypertensive basal ganglia hemorrhage .

  16. Prognostic factors of analysis on patients with nonoperative treatment of intracerebral hemorrhage in basal ganglia%非手术治疗自发性基底节区脑出血预后因素分析

    Institute of Scientific and Technical Information of China (English)

    周焜; 黄冠又; 梁郸; 乔志立; 陈冲; 王恒福; 饶正西; 王诚; 卓志平

    2013-01-01

    Objective To investigate the factors influencing prognosis of nonoperative treatment of intracerebral hemorrhage in basal ganglia. Methods The clinical data and survival status of 109 patients with intracerebral hemorrhage in basal ganglia who were admitted to Neurosurgery of Guiyang Second People' s Hospital during the period from April 2005 to June 2012 were reviewed retrospectively. The survival analysis was analyzed with Kaplan-Meier method. The univariate analysis was used to determine the prognositic factors related with survival rate by Log-rank test. Multivariate factors for the survival rates were analyzed using the Cox proportional hazards regression model. Results Univariate analysis revealed that GOS scale, GCS scale, hypertension, hemorrhage volume, intraventricu-lar hemorrhage, pulmonary infection and glucose were the factors influencing prognostic factors of hypertensive brainstem hemorrhage. Multivariate analysis showed that GCS scale, hemorrhage volume and glucose were independent prognostic factors. Conclusions GCS scale, hemorrhage volume and glucose were important prognostic factors of intracerebral hemorrhage in basal ganglia.%目的 探讨非手术治疗自发性基底节区出血预后相关的因素.方法 回顾性分析贵阳市第二人民医院神经外科2005年4月至2012年6月收治的109例随访资料完整的患者,采用Kaplan-Meier法进行单因素分析.Log-rank法进行生存率显著性检验,Cox比例风险回归模型作多因素分析.结果 单因素分析显示入院时GOS评分、GCS评分、高血压、出血量、出血破入脑室、肺部感染及血糖与预后有关联.多因素分析显示GCS评分、出血量和血糖是自发性基底节区出血预后相关的独立危险因素.结论 发病时GCS评分、出血量和血糖水平是影响患者预后的重要因素.

  17. Behavior Cognition Computational Model Based on Cerebellum and Basal Ganglia Mechanism%基于小脑-基底神经节机理的行为认知计算模型

    Institute of Scientific and Technical Information of China (English)

    陈静; 阮晓钢; 戴丽珍

    2012-01-01

    针对智能体的行为认知问题,提出一种小脑与基底神经节相互协调的行为认知计算模型.该模型核心为操作条件学习算法,包括评价机制、行为选择机制、取向机制及小脑与基底神经节的协调机制.初期的学习信号来自于下橄榄体和黑质两部分,在熵的意义上说明该算法是收敛的.采用该学习方法为自平衡两轮机器人建立运动神经认知系统,利用RBF网络逼近行为和评价网络.仿真实验表明该方法改善仅有基底神经节作用的行为-评价算法学习速度慢和失败次数多的问题,学习后期通过温度的不断降低,加快学习速度,震荡逐渐消失,改善学习效果.%Aiming at agent' s behavioral cognition problem, a behavior cognition computational model based on the coordination of cerebellum and basal ganglia is proposed. Operant conditioning learning algorithm is the central algorithm including evaluation mechanism, action selection mechanism, tropism mechanism, and the coordination mechanism between cerebellum and basal ganglia. The learning signals come from not only the Inferior Olive but also the Substantia Nigra in the beginning. The convergence of the algorithm can be guaranteed in the sense of entropy. With the proposed method, a motor nerve cognitive system for the self-balancing two-wheeled robot has been built using the RBF neural network as the actor and evaluation function approximator. The simulation results show that the learning speed is increased as well as the failure times are reduced by the proposed method than by the Actor-Critic method with the only Basal Ganglia mechanism. Through decreasing temperature in the late stage, the learning speed is increased and the vibration disappeares eventually, and the learning effect is improved.

  18. 经侧裂-岛叶入路治疗高血压性基底节血肿疗效观察%Effect of Surgical Treatment for Hypertensive Basal Ganglia Hematomas Through Transsylvian-insular Approach

    Institute of Scientific and Technical Information of China (English)

    张一; 杨常春; 王强; 董博; 王卉; 张峰极

    2012-01-01

      Objective:To summarize the clinical experience of surgical treatment through transsylvian—insular approach for hypertensive basal ganglia hematomas in 26 patients from the year 2009~2011.Methods: A total of 26 patients with hypertensive basal ganglia hematomas underwent surgical treatment through transsylvian—insular approach.Results: After surgery, hematoma was nearly total evacuated in 19 cases, more than 90% in 3 patients,less than 80% in 4 cases. Two patients died.Follow—up assessment according to GOS for 21~31 months revealed good in 13 patients,moderate handicapped in 8 patients,severely handicapped in 4 patients and death in 2 patients. Conclusions: Surgical treatment through transsylvian-insular approach was effective for hypertensive basal ganglia hematomas patients.%  目的:分析经侧裂-岛叶入路治疗高血压基底节血肿疗效及手术要点。方法:回顾性分析我院2009年~2011年26例经侧裂-岛叶入路治疗的高血压基底节血肿患者的临床资料,手术方法及疗效。结果:26例患者中血肿完全清除19例,血肿清除率>90%3例,血肿清除率<80%4例。本组患者死亡2例,1例死于再出血,1例死于严重肺部感。存活患者随访21~31个月,按格拉斯哥预后评分(GOS评分),良好者13例,中残8,重残4,死亡1例。结论:经侧裂岛叶入路是治疗高血压性基底节出血的良好手术方式。

  19. 精神分裂症患者基底节功能连接的静息态 fMRI 研究%Resting - state functional magnetic resonance imaging study of functional connectivity of basal ganglia in schizophrenia

    Institute of Scientific and Technical Information of China (English)

    蒋宇超; 陈琳; 段明君; 陈曦; 杨宓; 邓佳燕; 赖永秀; 尧德中; 罗程

    2015-01-01

    Objective To explore the difference of functional connectivity of basal ganglia in schizophrenia during a resting state by functional magnetic resoncance imaging(fMRI). Methods 3. 0T fMRI was used to assess the whole brain activity of 15 schizophrenia patients and 12 health controls. Functional connectivity analysis based on basal ganglia was performed to obtain the significant differ-ence between two groups. Results Compared with the health controls,the patients showed significantly increased functional connectiv-ity between media superior frontal gyrus,posterior cingulate and caudate;increased functional connectivity between left superior frontal gyrus,right anterior cingulate and left pallidum;increased functional connectivity between left medial frontal gyrus and right pallidum;increased functional connectivity between left superior frontal gyrus and left putamen. Conclusion This study discovers increased func-tional connectivity between basal ganglia and crucial regions of Default Model Network(DMN). The results imply that basal ganglia -DMN loop altered aberrantly,which might be associated with the pathological mechanisms of schizophrenia.%目的:通过功能磁共振(fMRI)技术,探讨精神分裂症患者静息状态下与基底节异常连接的脑区。方法采用3.0T 功能磁共振成像技术检测15例精神分裂症患者与12例正常对照组在静息状态下的全脑功能活动。采用功能连接分析对比两组被试的基底节(双侧尾状核、壳核和苍白球共6个区域)与全脑功能连接的差异。结果与对照组相比,精神分裂症患者的内侧额上回、后扣带与尾状核的功能连接上升;左侧额上回、右侧前扣带与左侧苍白球功能连接上升;左内侧额上回与右侧苍白球功能连接上升;左侧额上回与左侧壳核功能连接上升。差异均有统计学意义。结论精神分裂症患者的基底节区域与默认网络的重要节点功能连接上升,提

  20. MRI上抽动秽语综合征患者基底节核团体积的变化%MRI volume measurement of basal ganglia volumes in patients with Tourette's syndrome

    Institute of Scientific and Technical Information of China (English)

    卢洁; 李坤成; 曹燕翔; 张晓华; 张苗; 隋昕

    2009-01-01

    目的 探讨MR测量基底节核团体积对抽动秽语综合征(Tourette's syndrome,TS)病因诊断的价值.方法 选取10例TS患者(TS组)和10名健康志愿者(对照组)进行MR扫描,分别测量双侧尾状核、壳核、苍白球的体积,对两侧的基底节体积采用配对t检验进行比较分析;将大脑ROI体积数值进行标准化处理,对TS组和对照组之间基底节体积采用独立样本t检验进行比较分析.结果 正常对照组左侧尾状核、壳核、苍白球体积及3者之和均大于右侧(P值均<0.05),TS组上述结构两侧比较差异尤统计学意义(P值均>0.05).根据大脑体积进行标准化处理后,TS患者左侧尾状核、壳核、苍白球体积分别为(7.06±0.48)、(8.81±1.01)、(2.64±0.38)cm3,正常对照组分别为(11.05±1.86)、(9.97±1.11)、(3.04 ± 0.37)cm3,TS组较对照组减小(t值分别为-6.577、-2.457、-2.376,P值均<0.05);TS组右侧尾状核体积[(7.32 ± 0.26)cm3]较对照组[(9.81 ±1.83)cm3]减小(t=-4.258,P<0.01),右侧壳核、苍白球体积与对照组比较差异尤统计学意义(P值均>0.05).结论 MRI显示TS患者基底节核团体积减小,这对研究其病理生理机制及神经病理变化有一定的价值.%Objective To evaluate MRI measurement of basal ganglia volumes in patients with Tourette's syndrome.Methods Ten patients with Tourette's syndrome(TS)and 10 healthy volunteers were studied.Volumes of bilateral candate,putamen and pallidum were measured,and the results were analyzed using paired t test.The basal ganglia volume was normalized according to individual brain volume.The basal ganglia volumes of TS patients were compared with normal control group using independent-sample t tesL Results In 10 healthy volunteers,volumes of the left caudate,putamen,pallidum were significantly larger compared with those of the right side(P<0.05).However,there were no significant differenees between bilateral basal ganglia volumes(P>0.05)in TS patients

  1. 印度人基底神经节英语书写功能的PET-CT研究%The function of basal ganglia in English writing:A PET-CT study on Indians

    Institute of Scientific and Technical Information of China (English)

    邢一兰; 刘晓加; 吴湖柄; 陈东

    2009-01-01

    Objective To explore the neuropsychological mechanism of basal ganglia in English writing and elucidate law of alphabetic writing by means of PET-CT. Methods Subjects were six healthy Indian overseas students,sophomore and junior undergraduate. PET-CT examinations of the pseudo-writing and the English writing were carried out successively with an interval of 3~5 days. Statistical parametric mapping (SPM) was used to compare the datum of the two tasks through paired-t test. After analyzing areas where the metabolism of glucose changed the images about activated cerebral regions in English writing were obtained. Results The metabolism of glucose in leftpatamen(x=-30,y=-11,z=4,t=2.34, Z=1.84, P=0.033) andcaudatehead(x=-8,y= 17, z=-4, t=2.08, Z=1.70, P=0.045) were increased in the comparison between English writing and English pseudo-writing. Conclusion Left basal ganglia participates in English writing with contralateral cerebral domi-nance in right-handedness.%目的 应用正电子发射计算机体层显像-计算机体层显像(PET-CT)探讨基底神经节在印度人英语书写中的神经心理学机制,并在此基础七阐释拼音文字书写规律.方法 以6名健康的大学本科印度留学生为研究对象,每人分别执行假写和英语书写作业,采用PET-CT进行扫描并获得数据,通过统计参数图对假写和英语书写的图像数据进行配对t检验.分析葡萄糖代谢变化的区域,获得英语书写所引起的脑功能激活图.结果 英语书写与假写比较时,左侧壳核(x=-30,Y=-11,z=4,t值=2.34,Z值=1.84,P值=0.033)、尾状核头(X=-8,Y=17,z=-4,t值=2.08,z值=1.70,P值=0.045)葡萄糖代谢增加.结论 左侧基底神经节参与英语书写过程,并在右利手人群中具有对侧优势性.

  2. Differential contributions of the globus pallidus and ventral thalamus to stimulus-response learning in humans.

    Science.gov (United States)

    Schroll, Henning; Horn, Andreas; Gröschel, Christine; Brücke, Christof; Lütjens, Götz; Schneider, Gerd-Helge; Krauss, Joachim K; Kühn, Andrea A; Hamker, Fred H

    2015-11-15

    The ability to learn associations between stimuli, responses and rewards is a prerequisite for survival. Models of reinforcement learning suggest that the striatum, a basal ganglia input nucleus, vitally contributes to these learning processes. Our recently presented computational model predicts, first, that not only the striatum, but also the globus pallidus contributes to the learning (i.e., exploration) of stimulus-response associations based on rewards. Secondly, it predicts that the stable execution (i.e., exploitation) of well-learned associations involves further learning in the thalamus. To test these predictions, we postoperatively recorded local field potentials (LFPs) from patients that had undergone surgery for deep brain stimulation to treat severe movement disorders. Macroelectrodes were placed either in the globus pallidus or in the ventral thalamus. During recordings, patients performed a reward-based stimulus-response learning task that comprised periods of exploration and exploitation. We analyzed correlations between patients' LFP amplitudes and model-based estimates of their reward expectations and reward prediction errors. In line with our first prediction, pallidal LFP amplitudes during the presentation of rewards and reward omissions correlated with patients' reward prediction errors, suggesting pallidal access to reward-based teaching signals. Unexpectedly, the same was true for the thalamus. In further support of this prediction, pallidal LFP amplitudes during stimulus presentation correlated with patients' reward expectations during phases of low reward certainty - suggesting pallidal participation in the learning of stimulus-response associations. In line with our second prediction, correlations between thalamic stimulus-related LFP amplitudes and patients' reward expectations were significant within phases of already high reward certainty, suggesting thalamic participation in exploitation. PMID:26220740

  3. Differential contributions of the globus pallidus and ventral thalamus to stimulus-response learning in humans.

    Science.gov (United States)

    Schroll, Henning; Horn, Andreas; Gröschel, Christine; Brücke, Christof; Lütjens, Götz; Schneider, Gerd-Helge; Krauss, Joachim K; Kühn, Andrea A; Hamker, Fred H

    2015-11-15

    The ability to learn associations between stimuli, responses and rewards is a prerequisite for survival. Models of reinforcement learning suggest that the striatum, a basal ganglia input nucleus, vitally contributes to these learning processes. Our recently presented computational model predicts, first, that not only the striatum, but also the globus pallidus contributes to the learning (i.e., exploration) of stimulus-response associations based on rewards. Secondly, it predicts that the stable execution (i.e., exploitation) of well-learned associations involves further learning in the thalamus. To test these predictions, we postoperatively recorded local field potentials (LFPs) from patients that had undergone surgery for deep brain stimulation to treat severe movement disorders. Macroelectrodes were placed either in the globus pallidus or in the ventral thalamus. During recordings, patients performed a reward-based stimulus-response learning task that comprised periods of exploration and exploitation. We analyzed correlations between patients' LFP amplitudes and model-based estimates of their reward expectations and reward prediction errors. In line with our first prediction, pallidal LFP amplitudes during the presentation of rewards and reward omissions correlated with patients' reward prediction errors, suggesting pallidal access to reward-based teaching signals. Unexpectedly, the same was true for the thalamus. In further support of this prediction, pallidal LFP amplitudes during stimulus presentation correlated with patients' reward expectations during phases of low reward certainty - suggesting pallidal participation in the learning of stimulus-response associations. In line with our second prediction, correlations between thalamic stimulus-related LFP amplitudes and patients' reward expectations were significant within phases of already high reward certainty, suggesting thalamic participation in exploitation.

  4. Clinical analysis of symmetrical pathological changes involving bilateral basal ganglia in 28 children.%儿童基底节对称性病变28例临床分析

    Institute of Scientific and Technical Information of China (English)

    徐三清; 刘艳; 方峰; 周华; 罗小平

    2009-01-01

    Objective To explore and analyze the pathogenesis,clinical characteristics and prognosis of symmetrical pathological changes involving bilateral basal ganglia in children. Methods Analyzing retrospectively clinical data of 28 inpatients with the performance of brain damage and symmetrical low-density lesions on plain CT scans and/or low-signal on MRI T1 weighted imaging, high-signal on MRI T2 weighted imaging involving bilateral basal ganglia. Results Six patients first had fever,cough and (or) vomiting,diarrhea and subsequently progressed rapidly to convulsions, coma and also had marked acidosis, increased blood lactate and pyruvate levels,in which three cases were diagnosed as methylmalonic acidaemia,two were diagnosed as α-keto-glutaric aciduria,one was diagnosed as lactic academia;One 7-month-old infant with delayed motor development,feeding difficulties and repeated seizure was diagnosed as lactic academia;One simple breast-feeding patient with cerebral vitamine Bl deficiency had hoarse cry,muscular weakness,convulsion and good effect to vitamine Bl intramuscular injection;Eighteen cases with hepatolenticular degeneration had muscular hypertonia,tremor, salivation, ataxia, speech unclear and memory decline, in which 13 cases were accompanied by hepatomegaly, 10 cases were accompanied by splenomegaly,two cases were accompanied by liver cirrhosis and two cases were accompanied by hypersplenism; One case with moldy sugarcane poisoning and one case with carbon monoxide-induced toxic encephopathy had cognitive and motor dysfunction which recovered slowly. Conclusion Many causes can lead to symmetrical pathological changes involving bilateral basal ganglia with diverse symptoms in children. The diseases should be diagnosed early by illness history, clinical features, imaging study and laboratory tests including the screening for metabolic disorders, which can help treat them effectively and improve the prognosis.%目的 探讨和分析儿童基底节区对称性

  5. Neural activity in the rat basal ganglia

    NARCIS (Netherlands)

    Zhao, Y.; Stegenga, J.; Heida, T.; Wezel, van R.J.A.

    2013-01-01

    Objectives: Pathological oscillations in the beta frequencies (8-30Hz) have been found in the local field potentials of Parkinson's disease (PD) patients and non-human primate models of PD1. In particular, these synchronizations appear in the subthalamic nucleus (STN), a common target for deep brain

  6. Basal ganglia contributions to adaptive navigation.

    Science.gov (United States)

    Mizumori, Sheri J Y; Puryear, Corey B; Martig, Adria K

    2009-04-12

    The striatum has long been considered to be selectively important for nondeclarative, procedural types of memory. This stands in contrast with spatial context processing that is typically attributed to hippocampus. Neurophysiological evidence from studies of the neural mechanisms of adaptive navigation reveals that distinct neural systems such as the striatum and hippocampus continuously process task relevant information regardless of the current cognitive strategy. For example, both striatal and hippocampal neural representations reflect spatial location, directional heading, reward, and egocentric movement features of a test situation in an experience-dependent way, and independent of task demands. Thus, continual parallel processing across memory systems may be the norm rather than the exception. It is suggested that neuromodulators, such as dopamine, may serve to differentially regulate learning-induced neural plasticity mechanisms within these memory systems such that the most successful form of neural processing exerts the strongest control over response selection functions. In this way, dopamine may serve to optimize behavioral choices in the face of changing environmental demands during navigation. PMID:19056429

  7. Multiplexed coding in the human basal ganglia

    Science.gov (United States)

    Andres, D. S.; Cerquetti, D.; Merello, M.

    2016-04-01

    A classic controversy in neuroscience is whether information carried by spike trains is encoded by a time averaged measure (e.g. a rate code), or by complex time patterns (i.e. a time code). Here we apply a tool to quantitatively analyze the neural code. We make use of an algorithm based on the calculation of the temporal structure function, which permits to distinguish what scales of a signal are dominated by a complex temporal organization or a randomly generated process. In terms of the neural code, this kind of analysis makes it possible to detect temporal scales at which a time patterns coding scheme or alternatively a rate code are present. Additionally, finding the temporal scale at which the correlation between interspike intervals fades, the length of the basic information unit of the code can be established, and hence the word length of the code can be found. We apply this algorithm to neuronal recordings obtained from the Globus Pallidus pars interna from a human patient with Parkinson’s disease, and show that a time pattern coding and a rate coding scheme co-exist at different temporal scales, offering a new example of multiplexed neuronal coding.

  8. Vestibular interactions in the thalamus

    Directory of Open Access Journals (Sweden)

    Aaron eCamp

    2015-12-01

    Full Text Available It has long been known that the vast majority of all information en route to the cerebral cortex must first pass through the thalamus. The long held view that the thalamus serves as a simple hi fidelity relay station for sensory information to the cortex, however, has over recent years been dispelled. Indeed, multiple projections from the vestibular nuclei to thalamic nuclei (including the ventrobasal nuclei, and the geniculate bodies- regions typically associated with other modalities- have been described. Further, some thalamic neurons have been shown to respond to stimuli presented from across sensory modalities. For example, neurons in the rat anterodorsal and laterodorsal nuclei of the thalamus respond to visual, vestibular, proprioceptive and somatosensory stimuli and integrate this information to compute heading within the environment. Together, these findings imply that the thalamus serves crucial integrative functions, at least in regard to vestibular processing, beyond that imparted by a simple relay. In this mini review we outline the vestibular inputs to the thalamus and provide some clinical context for vestibular interactions in the thalamus. We then focus on how vestibular inputs interact with other sensory systems and discuss the multisensory integration properties of the thalamus.

  9. 基底节区血肿经外侧裂-岛叶手术入路的解剖学研究%Anatomical Study of the Surgical Approach to the Lateral Fissure of the Hematoma in the Basal Ganglia Region

    Institute of Scientific and Technical Information of China (English)

    贾振锋

    2015-01-01

    目的:研究基底节区血肿经外侧裂-岛叶手术入路的解剖学特点。方法对20例40侧成人尸头标本的外侧裂、岛叶、大脑基底节等进行相关解剖。结果岛叶的供血动脉为大脑中动脉 M2段,扇形展开,方向为从岛叶表面向后上,并将很多微小的穿支血管发出来对岛叶皮层进行供应;岛叶的中后短回在其中部水平切面上垂直向内和内囊膝部及壳核最为宽阔的部分相对应。结论深入研究基底节区血肿经外侧裂-岛叶手术入路的解剖学特点能够为临床手术治疗基底节区血肿提供科学有效的依据。%Objective To study the basal ganglia hematoma through lateral fissure-the insular cortex anatomy surgical approach. Methods 20 cases of 40 adult cadaver specimens side lateral fissure, insular cortex, basal ganglia and other brain related anatomy. Results For insular artery middle cerebral artery M2 segment, fan, backward direction from the island leaf surface, and a lot of small penetrating vessels issued to the supply of the insular cortex conducted, after a short return to the island leaves in which the upper portion of the horizontal section vertical knee inwards and the internal capsule and putamen most broad section correspond. Conclusion Depth study by the lateral fissure basal ganglia hematoma-the insular cortex anatomy surgical approach for clinical surgery can basal ganglia hematoma provide scientifically valid basis.

  10. 成人自发性基底节区脑出血患者日常生活活动能力的影响因素%Factors Affecting Activities of Daily Living in Patients with Spontaneous Basal Ganglia Hemorrhage

    Institute of Scientific and Technical Information of China (English)

    张志竖; 邹耀兵; 肖静; 江思德; 潘成德; 饶富兰; 张建新; 唐明山

    2011-01-01

    Objective To investigate the factors affecting activities of daily life (ADD in patients with first basal ganglia hemorrhage, and to formulate intervention strategies for improving the capability of ADL. Methods A prospective study was conducted on 97 patients with the first spontaneous intracerebral hemorrhage who survived with no surgical treatment. Demographic risk factors for stroke were examined and National Institute of Health stroke scale (NIHSS) and Glasgow coma score (GCS) were recorded on the day of admission. White blood cell(WBC) count and plasma glucose (PG) were measured on the second day of hospitalization. NIHSS score and Barthel index (BI) were recorded 3 weeks after onset. Occurrences of urinary tract and lung infection were determined after discharge from hospital. BI was recorded by clinic or telephone follow-up 3 months after onset. Results The amount of bleeding,initial PG levels, WBC count and initial NIHSS score were independently associated with BI at 3 weeks and 3 months after spontaneous intracerebral hemorrhage. Furthermore, urinary tract infection and the history of ischemic stroke were associated with BI at 3 months after intracerebral hemorrhage. Conclusion Positive measures should be taken to control risk factors so as to improve the capability of ADL in patients with spontaneous intracerebral hemorrhage.%目的 探讨未行手术治疗的成人首发基底节区脑出血患者日常生活活动能力的影响因素,以期早期制定干预措施,提高患者日常生活活动能力.方法 采用前瞻性队列研究连续收集成人首发基底节区脑出血未行手术治疗且存活的患者97例.入院当天记录人口基线资料,进行卒中危险因素调查,行美国国立卫生研究所脑卒中评分(national institute of health stroke scale,NIHSS)和格拉斯哥昏迷评分(GCS);入院次日清晨行白细胞计数、空腹血糖等多项实验室指标的测定;发病3周行NIHSS评分及Barthel指数(Barthelindex

  11. 基底神经节区梗死后失写症的神经心理学分析%The Neuropsychological Analysis of Agraphia After Basal Ganglia Infarction

    Institute of Scientific and Technical Information of China (English)

    金梅; 刘晓加; 陈东; 尹文刚

    2008-01-01

    目的:研究基底神经节(BG)区梗死所致汉语失写症的神经心理学特点.方法:采用汉语失写检查法(CAB)测试40例BG区梗死患者的书写能力,计算各项书写得分和失写指数.对失写组和非失写组头颅CT或MRI进行标准化处理,显示病灶并进行二维平面叠加,直观显示其病灶的集中趋势.结果:在40例患者中,左侧BG区损害21例,失写17例;右侧损害19例,失写4例.神经影像学二维叠加显示,BG区梗死致失写的病灶多位于左侧BG区,包括左侧壳核、尾状核头部和尾状核体;而较少位于右侧壳核和右侧尾状核体.BG区梗死所致失写以失语性失写为主,其特点为构字障碍、字词错写和语法错误.结论:BG区梗死可导致失语性失写症,提示BG参与了书写加工过程,是书写这一高级神经功能的皮质下中枢.%Objective:To investigate the neuropsychological characteristics of Chinese agraphia caused by basal ganglia(BG)infarction.Methods:The writing abilities of 40 patients with BG infarction were detected by Chinese agraphia battery(CAB),and all the writing scores and agraphia quotient were calculated.The head CT/MRI images in agraphia and non-agraphia groups were standardized,the infarction were revealed and the superposition of two-dimensional arrays were performed,so that the central tendency of infarction was visually displayed.Results: Among the 40 patients,21 had left BG infraction,and 17 had agraphia;19 had right BG infraction,and 4 had agraphia.The two-dimensional superimposing neuroimages showed that BG infarctions caused agraphia was mostly in the left BG,including the left putamen,the head and body of the caudate nucleus,but there were fewer infarctions in the right putamen and the body of the candate nucleus.BG infarction caused agraphia was mostly aphasic agraphia,which was characterized by the orthographic disorders,paragraphia,and grammar mistakes.Conclusions: BG infarction may result in aphasic agraphia

  12. MR measurement of the basal ganglia volume in the Tourette syndrome%抽动秽语综合征患者双侧基底节结构体积的MR测量

    Institute of Scientific and Technical Information of China (English)

    廖凯兵; 黎桂平; 杨波; 冯敢生

    2014-01-01

    Objective To compare the volume of the basal ganglia in patients with Tourette syndrome(T S) and the normal volunteers and to explore the underlying anatomical basis of TS.Methods Thirty-one cases of TS (TS subjects),31 gender and age-matched subjects (the control subjects) were examined on a 3.0 T MRI system.The volume of the caudate nucleus,globus pallidus,putamen of the two sides and the brain volume were measured with volume analysis software,and the data were normalized according to the individual brain volume.Statistical analysis was performed using t test to compare between the TS subjects and the controls.Results The volume of the both sides of the caudate nucleus,putamen and globus pallidus of TS subjects were (4.11 ±0.12) and (3.76 ±0.11),(2.28 ±0.12)and(2.35 ±0.28),(4.98 ±0.20) and (4.89 ±0.31)cm3,while they were (4.88 ±0.19) and (4.30 ±0.12),(2.28 ±0.12)and (2.35 ± 0.28),(4.98 ± 0.20) and (4.89 ± 0.31) cm3 in the controls,respectively.There were significant differences in the bilateral caudate nucleus and globus pallidus between the TS subjects and control subjects (t =2.97,1.74,3.72,3.93,P < 0.05),but there were no significant differences of the volume in the bilateral putamen between the TS and control subjects(t =0.47,1.31,P >0.05).The volume was not significantly different between the left and right caudate nucleus in the TS subjects (t =1.81,P >0.05),but the left volume of the caudate nucleus was bigger in the control subjects compared with the right volume,however,there was significant difference between the bilateral caudate nucleus in the control subjects (t =2.34,P < 0.05).There were no differences of volume between the bilateral globus pallidus and putamen in both the TS and control subjects (t =1.12,1.44,1.68,0.38,P > 0.05).Conclusion The abnormal volume of caudate nucleus,putamen,and the globus pallidus may be involved in the pathogenesis of TS.%目的 对比研究抽动秽语综合征(TS)患者与健康志愿者基底

  13. Neuronal firing in the globus pallidus internus and the ventrolateral thalamus related to parkinsonian motor symptoms

    Institute of Scientific and Technical Information of China (English)

    CHEN Hai; ZHUANG Ping; ZHANG Yu-qing; LI Jian-yu; LI Yong-jie

    2009-01-01

    Background It has been proposed that parkinsonian motor signs result from hyperactivity in the output nucleus of the basal ganglia, which suppress the motor thalamus and cortical areas. This study aimed to explore the neuronal activity in the globus pallidus internus (GPi) and the ventrolateral thalamic nuclear group (ventral oral posterior/ventral intermediate, Vop/Vim) in patients with Parkinson's disease (PD).Methods Twenty patients with PD who underwent neurosurgery were studied. Microelectrode recording was performed in the GPi (n=10) and the Vop/Vim (n=10) intraoperatively. Electromyography (EMG) contralateral to the surgery was simultaneously performed. Single unit analysis was carried out. The interspike intervals (ISI) and coefficient of variation (CV) of ISI were calculated. Histograms of ISI were constructed. A unified Parkinson's disease rating scale (UPDRS) was used to assess the clinical outcome of surgery.Results Three hundred and sixty-three neurons were obtained from 20 trajectories. Of 175 GPi neurons, there were 15.4% with tremor frequency, 69.2% with tonic firing, and 15.4% with irregular discharge. Of 188 thalamic neurons, there were 46.8% with tremor frequency, 22.9% with tonic firing, and 30.3% with irregular discharge. The numbers of three patterns of neuron in GPi and Vop/Vim were significantly different (P <0.001). ISI analysis revealed that mean firing rate of the three patterns of GPi neurons was (80.9±63.9) Hz (n=78), which was higher than similar neurons with 62.9 Hz in a normal primate. For the Vop/Vim group, ISI revealed that mean firing rate of the three patterns of neurons (n=95) was (23.2±17.1) Hz which was lower than similar neurons with 30 Hz in the motor thalamus of normal primates. UPDRS indicated that the clinical outcome of pallidotomy was (64.3±9.5)%, (83.4±19.1)% and (63.4±36.3)%, and clinical outcome of thalamotomy was (92.2±12.9)%, (68.0±25.2)% and (44.3±27.2)% for tremor, rigidity and bradykinesia, respectively

  14. Basal ganglia structure abnormalities of the children with the first-episode tic disorder: A magnetic resonance imaging study%首发抽动障碍儿童基底节结构异常的磁共振成像研究

    Institute of Scientific and Technical Information of China (English)

    孙锦华; 黄明金; 袁爱花; 李茜茜; 黄晓琦; 龚启勇; 郭兰婷

    2012-01-01

    目的:探讨抽动障碍(TD)儿童基底节结构异常特点及其与病程、疾病严重程度之间的相关性.方法:对9例符合美国精神障碍诊断与统计手册第4版(DSM-Ⅳ)中TD标准的首发未用药6~14岁TD儿童,采用耶鲁综合抽动严重程度量表(YGTSS)对TD儿童进行临床评估,同时收集9例8~10岁健康儿童,对受试者进行脑结构磁共振扫描,采用感兴趣区法对基底节及其亚区尾状核、壳核、苍白球分别进行测量,比较两组上述脑区的原始体积、相对体积(原始体积/颅内总体积)、左右不对称性指数(Al)的差异,分析基底节及其各亚区体积与患者病程、YGTSS总分之间相关性.结果:患儿组右侧苍白球原始体积[(1.4±0.2)mL vs.(1.1±0.1)mL]及其相对体积[(0.9±0.1)×10-3 vs.(0.7±0.2)×10-3]均高于对照组(均P<0.01);其他各结构原始体积及其相对体积组间差异均无统计学意义(均P>0.05).患儿组尾状核体积[(4.9±0.4)mL vs.(4.7±0.5)mL]和对照组尾状核体积两组组内左右侧比较[(4.7±0.5)mL vs.(4.5±0.5)mL],结果显示左侧均高于右侧(均P<0.05);其他各结构组内左右侧体积的比较,差异均无统计学意义(均P>0.05).两组间基底节及其各亚区AI值差异无统计学意义(P>0.05);患儿组各结构相对体积与YGTSS总分(r=-0.08 ~0.63)和病程(r=-0.09 ~0.59)均无明显相关(均P>0.05).结论:抽动障碍儿童脑右侧苍白球体积明显大于健康儿童,可能为该症的异常脑结构之一;抽动障碍儿童基底节及各亚区结构体积大小与病程、疾病严重程度无明显相关.%Objective: To explore the brain structural characteristics of the basal ganglia of children with tic disorder (TD) and the correlations between the structural abnormailities and the duration or severity of TD. Methods: Using brain structural magnetic resonance imaging technique (MRO), we recruited 9 unmedicated, 6 - 14 years old, the first episode

  15. The recent prognosis after operation of hypertensive basal ganglia hemorrhage by using CT perfusion imaging%应用 CT 灌注成像预测基底节区高血压脑出血术后近期预后的研究

    Institute of Scientific and Technical Information of China (English)

    郑念东; 张道宝; 万晓强; 王山; 卫正洪

    2016-01-01

    目的:探讨CT灌注成像对基底节区高血压脑出血术后近期预后的评估作用。方法2012年6月至2013年9月高血压脑出血术后患者81例,术后两周行基底节区CT灌注成像,术后3月为患者行日常生活能力( ADL)分级评估,了解患者近期预后与术区局部脑血容量( rCBV)、局部脑血流量( rCBF)、平均通过时间( MTT)的相关性。结果 Logistic多元回归分析结果显示,rCBV、rCBF及MTT是影响患者预后的独立危险因素,患者近期预后与rCBV、rCBF呈正相关,与MTT呈负相关( P<0.05)。结论 CT灌注成像对预测患者近期预后有指导意义,患者的近期预后和术区周围脑组织的灌注状态密切相关,灌注越好,患者的近期预后越好。%Objective To investigate the evaluation effect of CT perfusion imaging on recent prognosis of hypertensive basal ganglia hemorrhage after operation .Methods Eighty-one patients with hypertensive basal ganglia hemorrhage after operation from June 2012 to September 2013 received CT perfusion imaging examination after 2 weeks of operation .Ability of daily life was estimated after 3 months of operation .The correlation between the recent prognosis and rCBV ,rCBF and MTT of operation area was explored .Results Logistic multivariate regression analysis showed that rCBV ,rCBF and MTT were independent risk factors of prognosis .The recent prog-nosis was positively correlated with rCBV and rCBF but negatively correlated with MTT ( P<0.05 ) .Conclusion The CT perfusion imaging has a guiding significance for recent prognosis of the patients .The recent prognosis was closely related to the brain tissue perfu-sion status in the operation area .The better perfusion the patients have ,they may have better recent prognosis .

  16. Association Between Depressive Disorders and Early Progressive Motor Deficits Among Patients with Cerebral Infarcts in Basal Ganglia Region%抑郁障碍与基底节区脑梗死患者早期运动障碍加重的关系

    Institute of Scientific and Technical Information of China (English)

    伍明; 李梅笑

    2013-01-01

    Objective To explore the impact of depressive disorders on early progressive motor deficits among patients with cerebral infarcts of basal ganglia region.Methods Eighty-five patients with first cerebral infarcts in basal ganglia region were enrolled into this study.All patients were examined with brain magnetic resonance imaging (MRI),magnetic resonance angiography (MRA) and diffusion weighted imaging (DWI).According to the Hamilton Depression Rating Scale scores on admission,patients were divided into non-depressive disorders group and depressive disorders group.Based on NIHSS scores of early progressive motor deficits,each above-mentioned group was further divided into stable subgroup and progressive subgroup.The occurrence rate of early progressive motor deficits,front-to-back ratio of volume of lesions (V2/V1),pathological changes in the middle cerebral artery (MCA),blood pressure,blood lipids and fasting blood glucose were compared between non-depressive disorders and depressive disorders groups.Results The occurrence rate of early progressive motor deficits in depressive disorders group was significantly higher than that of non-depressive disorders group (10/27,37.04 % vs 9/58,15.52%,x2 =4.92,P =0.03).MCAs were obviously stenosing or occlusive (37/85,43.53 %) in cerebral infarcts of basal ganglia region,but no statistically significant difference was found in the pathological changes in the MCA between non-depressive disorders and depressive disorders groups (x2 =0.34,P =0.56).V2/V1 of progressive subgroups was larger than that of stable subgroups,and V2/V1 of depressive disorders groups was significantly different from that of non-depressive disorders in progressive subgroups (F =167.39,P =0.00).Systolic blood pressure and fasting blood glucose were significantly higher in the progression of the disease,and there was a significantly correlation between fasting blood glucose and depressive disorders (r =0.425,P =0.000).Conclusions Depressive disorders

  17. 早期抗抑郁治疗对基底节区脑出血患者预后的影响研究%Effect of early anti-depression therapy on prognosis of patients with intracerebral hemorrhage in basal ganglia

    Institute of Scientific and Technical Information of China (English)

    吴丽华; 王怡雯; 郝磊; 田洪; 张玉波; 周虎传; 刘磊

    2015-01-01

    目的:探讨早期抗抑郁治疗对基底节区脑出血患者预后的影响。方法103例患者随机分为两组。对照组给予常规治疗和护理,实验组在对照组基础上给予早期抗抑郁治疗,包括早期心理干预和抗抑郁药物治疗。采用汉密尔顿抑郁量表评分(HAMD-17)、临床神经功能缺损评分(NFA)、简式Fugl-Meyer评分(FMA)及Barthel 指数BI评定,比较入院时和治疗后3个月的评分变化,评估患者抑郁状态、神经功能缺损、运动功能以及日常生活能力。结果治疗后3个月,与对照组比较,实验组HAMD评分、FMA评分、BI指数均优于对照组(P<0.01),两组NFA评分无显著差异(P>0.05)。结论早期抗抑郁治疗能够缓解基底节区脑出血患者的不良情绪,并能提高患者的预后和日常生活能力。%Objective To investigate the effect of early anti-depression therapy on the prognosis of patients with intracerebral hemorrhage in the basal ganglia .Methods 103 patients were randomly divided into 2 groups:anti-depression group and control group;routine treatment was provided to patients in both groups ,while anti-depression therapy was added to patients in anti-depression group , including early psychological intervention and anti-depression drugs;Hamilton Depression Scale ( HAMD-17 ) , Neurological Function Assessment(NFA),Fugl-Meyer Assessment(FMA),and Bathel Index(BI)were used to evaluated the conditions of patients in both groups and the changes of the scores at admission and 3 months after treatment were comparatively analyzed , the evaluation of depression,neurological deficits,motor function and activities of daily living was made .Results 3 months after treatment,the scores of HAMD,FMA and BI of the patients in anti-depression group were superior to those of the patients in control group (P0.05).Conclusion Early anti-depression therapy can relieve the unhealthy mood of the patients with

  18. Measurement of basal ganglia volume of patients with Parkinson disease using 3.0T MR susceptibility-weighted imaging%3.0T MR磁敏感加权成像测量帕金森病患者基底节区体积

    Institute of Scientific and Technical Information of China (English)

    刘芳; 范国光; 王慈; 徐克; 孙文阁

    2011-01-01

    Objective To analyze changes of basal ganglia volume of patients with Parkinson disease (PD ) with 3. OT MR SWI . Methods Totally 20 patients with early PD , 20 patients with advanced PD and 20 age-matched healthy suhjects underw ent MRI . The volumes of' caudate nucleus , putamen and globus pallidus were measured with SWI . Correlation analysis of basal ganglia volume with Hoehn & Yahr grading and the course of PD was carried out . Results Compared with that of normal volunteers . the volume of' putamen in patients with early PD decreased 10. 79% ( P

  19. 帕金森病患者基底节区的磁共振氨基质子转移成像研究%Amide proton transfer MR imaging at 3.0 T of the basal ganglia in Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    王蕊; 李春媚; 陈敏; 张晨; 周进元; 苏闻

    2015-01-01

    目的 探讨磁共振氨基质子转移成像(APT)技术对于发现帕金森病患者基底节异常改变的可行性.方法 收集27例帕金森病患者和23名年龄及性别相匹配的健康对照者进行头颅APT成像和常规磁共振检查.测量双侧苍白球、壳核和尾状核的酰胺质子不对称磁化转移率(MTRasym),分别采用独立样本t检验和配对样本t检验比较帕金森病患者与健康对照者、帕金森病患者起病侧和对侧各脑结构MTRasym (3.5 ppm)的差异.使用单因素方差分析比较健康对照者和不同严重程度帕金森病患者间各脑结构MTRasym(3.5 ppm)的差异.结果 帕金森病患者苍白球、壳核和尾状核的MTRasym (3.5 ppm)均高于健康对照者[分别为(0.89±0.12)%与(0.57 ±0.16)%,(1.05±0.11)%与(0.82±0.15)%,(1.15±0.13)%与(0.78 ± 0.19)%;t=3.311、2.562和3.277,均P<0.05].健康对照组、轻度和中重度帕金森病组基底节各脑结构MTRasym(3.5 ppm)的差异具有统计学意义,且轻度帕金森病患者苍白球、壳核和尾状核的MTRasym(3.5 ppm)明显高于健康对照者.帕金森病患者基底节各脑结构起病侧的MTRasym(3.5 ppm)虽均略低于对侧,但差异均无统计学意义.结论 APT成像技术可以敏感地显示早期帕金森病患者和健康对照者基底节各脑结构MTRasym(3.5 ppm)的差异,是一种评价帕金森病患者脑代谢异常的有效工具.%Objective To explore the feasibility of amide proton transfer (APT) MR imaging for the detection of basal ganglia abnormalities in patients with Parkinson' s disease (PD).Methods Twentyseven patients with PD and twenty-three age-matched normal control subjects underwent cerebral APT and structural MR imaging.The magnetic resonance ratio asymmetry (MTRasym) values at 3.5 ppm of bilateral globus pallidus,putamen and caudate were measured on APT images.MTRasym (3.5 ppm) values of cerebral structures between PD patients and control subjects were compared with

  20. Mediodorsal thalamus and cognition in nonhuman primates

    Directory of Open Access Journals (Sweden)

    Mark G Baxter

    2013-08-01

    Full Text Available Several recent studies in nonhuman primates have provided new insights into the role of the medial thalamus in different aspects of cognitive function. The mediodorsal nucleus of the thalamus (MD, by virtue of its connectivity with the frontal cortex, has been implicated in an array of cognitive functions. Rather than serving as an engine or relay for the prefrontal cortex, this area seems to be more specifically involved in regulating plasticity and flexibility of prefrontal-dependent cognitive functions. Focal damage to MD may also exacerbate the effects of damage to other subcortical relays. Thus a wide range of distributed circuits and cognitive functions may be disrupted from focal damage within the medial thalamus (for example as a consequence of stroke or brain injury. Conversely, this region may make an interesting target for neuromodulation of cognitive function via deep brain stimulation or related methods, in conditions associated with dysfunction of these neural circuits.

  1. PET activation in basal ganglia disorders: Parkinson's disease and dystonia

    International Nuclear Information System (INIS)

    This article reviews PET activation studies with performance of different motor paradigms (joy-stick movements, imagination of movement, writing) in patients with movement disorders. The focus will be on Parkinson's disease (PD) and dystonia. PET findings will be related to clinical and electrophysiological observations. PET activation studies before and after therapeutic interventions such as pallidotomy in Parkinson's disease and botulinum toxin in writer's cramp are described. The contribution of PET activation studies to the understanding of the pathophysiology of dystonia and PD is discussed. (orig.)

  2. Volumetric changes in the Basal Ganglia after antipsychotic monotherapy

    DEFF Research Database (Denmark)

    Ebdrup, B H; Nørbak, H; Borgwardt, S;

    2013-01-01

    monotherapy. Material and Methods: We systematically searched PubMed for longitudinal MRI studies of patients with schizophrenia or non-affective psychosis who had undergone a period of antipsychotic monotherapy. We used specific, predefined search terms and extracted studies were hand searched for additional...... studies. Results: We identified 13 studies published in the period from 1996 to 2011. Overall six compounds (two classified as FGAs and four as SGAs) have been investigated: haloperidol, zuclophentixol, risperidone, olanzapine, clozapine, and quetiapine. The follow-up period ranged from 3-24 months....... Unexpectedly, no studies found that specific FGAs induce significant BG volume increases. Conversely, both volumetric increases and decreases in the BG have been associated with SGA monotherapy. Discussion: Induction of striatal volume increases is not a specific feature of FGAs. Except for clozapine treatment...

  3. Light-Induced Alterations in Basil Ganglia Kynurenic Acid Levels

    Science.gov (United States)

    Sroufe, Angela E.; Whittaker, J. A.; Patrickson, J. W.; Orr, M. C.

    1997-01-01

    The metabolic synthesis, release and breakdown of several known CNS neurotransmitters have been shown to follow a circadian pattern entrained to the environmental light/dark cycle. The levels of excitatory amino acid (EAA) transmitters such as glutamate, have been shown to vary with environmental lighting conditions. Kynurenic Acid (KA), an endogenous tryptophan metabolite and glutamate receptor antagonist, has been reported to have neuroprotective effects against EAA-induced excitotoxic cell damage. Changes in KA's activity within the mammalian basal ganglia has been proposed as being contributory to neurotoxicity in Huntington's Disease. It is not known whether CNS KA levels follow a circadian pattern or exhibit light-induced fluctuations. However, because the symptoms of certain degenerative motor disorders seem to fluctuate with daily 24 hour rhythm, we initiated studies to determine if basal ganglia KA were influenced by the daily light/dark cycle and could influence motor function. Therefore in this study, HPLC-EC was utilized to determine if basal ganglia KA levels in tissue extracts from adult male Long-Evans rats (200-250g) entrained to 24 and 48 hours constant light and dark conditions, respectively. Samples were taken one hour before the onset of the subjective day and one hour prior to the onset of the subjective night in order to detect possible phase differences in KA levels and to allow for accumulation of factors expressed in association with the light or dark phase. Data analysis revealed that KA levels in the basal ganglia vary with environmental lighting conditions; being elevated generally during the dark. Circadian phase differences in KA levels were also evident during the subjective night and subjective day, respectively. Results from these studies are discussed with respect to potential cyclic changes in neuronal susceptibility to excitotoxic damage during the daily 24 hour cycle and its possible relevance to future therapeutic approaches in

  4. What is the Thalamus in Zebrafish?

    Directory of Open Access Journals (Sweden)

    Thomas eMueller

    2012-05-01

    Full Text Available Current research on the thalamus and related structures in the zebrafish diencephalon identifies an increasing number of both neurological structures and ontogenetic processes as evolutionary conserved between teleosts and mammals. The patterning processes, for example, which during the embryonic development of zebrafish form the thalamus proper appear largely conserved. Yet also striking differences between zebrafish and other vertebrates have been observed, particularly when we look at mature and histologically differentiated brains. A case in point is the migrated preglomerular complex of zebrafish which evolved only within the lineage of ray-finned fish and has no counterpart in mammals or tetrapod vertebrates. Based on its function as a sensory relay station with projections to pallial zones, the preglomerular complex has been compared to specific thalamic nuclei in mammals. However, no thalamic projections to the zebrafish dorsal pallium, which corresponds topologically to the mammalian isocortex, have been identified. Merely one teleostean thalamic nucleus proper, the auditory nucleus, projects to a part of the dorsal telencephalon, the pallial amygdala. Studies on patterning mechanisms identify a rostral and caudal domain in the embryonic thalamus proper. In both, teleosts and mammals, the rostral domain gives rise to GABAergic neurons, whereas glutamatergic neurons originate in the caudal domain of the zebrafish thalamus. The distribution of GABAergic derivatives in the adult zebrafish brain, furthermore, revealed previously overlooked thalamic nuclei and redefined already established ones. These findings require some reconsideration regarding the topological origin of these adult structures. In what follows, I discuss how evolutionary conserved and newly acquired features of the developing and adult zebrafish thalamus can be compared to the mammalian situation.

  5. The Treatment of Intracranial Hematoma Drainage by Drilling Cranium at the Frontal Region for Basal Ganglia Hemorrhage in 109 Cases%额部钻颅血肿引流术治疗高血压基底节区脑出血109例

    Institute of Scientific and Technical Information of China (English)

    罗德群

    2012-01-01

    目的 探索一种新的手术方法治疗高血压脑出血,既能避开重要功能区及重要血管分布区,又能达到与其他穿刺术式引流效果相仿. 方法 回顾性分析我科2010年8月至2011年10月行新术式穿刺的高血压脑出血患者109例,所有患者均经头颅CT确诊,根据多田公式计算出血量,分别采用局麻或全麻下额部钻颅软通道引流血肿78例,额部钻颅血肿引流配合脑室外引流20例,单纯行脑室外引流术11例. 结果 术后2~5d复查头颅CT示:血肿完全清除19例;血肿清除90%以上37例,血肿清除80%以上43例,清除50%以上8例,血肿清除小于50%2例;未发生切口及颅内感染;术后死亡6例. 结论 额部钻颅血肿引流术治疗高血压基底节区脑出血能有效避免对重要脑组织的损伤,减少手术并发症;血肿清除率高,提高了患者的生存率和生存质量.%Objective To explore a new operative method for the treatment of hypertensive cerebral hemorrhage which can avoid the damage to the functional area and important vascular area while also can a-chieve the same therapeutic equivalence as traditional operations. Methods The clinical results were retrospectively analyzed in 109 cases of hypertensive cerebral hemorrhage underwent the new operative method in our department from August, 2010 to October, 2011. All the cases were confirmed by CT scam as the basal ganglia hemorrhage. Intracranial hematoma drainage by drilling cranium at the frontal region was done for all the cases. Results Two to five days after operation, the intracranial hematoma was completely disappeared in 19 patients, 90% above cleared in 37 patients, 80% above cleared in 43 patients, 50% above cleared in 8 patients and less than 50% decreased in 2 patients. Neither intracranial infection nor wound infection was observed. Six patients died after the operation. Conclusion It can effectively avoid the damage to the important brain tissue, decrease complications

  6. Thalamus lesions in chronic and acute seizure disorders

    Energy Technology Data Exchange (ETDEWEB)

    Tschampa, Henriette J.; Greschus, Susanne; Urbach, Horst [University of Bonn, Department of Radiology (Neuroradiology), Bonn (Germany); Sassen, Robert; Bien, Christian G. [University of Bonn, Department of Epileptology, Bonn (Germany)

    2011-04-15

    Transient signal changes in the pulvinar have been described following status epilepticus. However, we observed persistent thalamus changes after seizures. The purpose of this study was to characterize thalamus changes in patients with seizure disorders and to correlate imaging findings with clinical features. We searched among 5,500 magnetic resonance imaging (MRI) exams performed in patients with seizures and identified 43 patients. The MRI scans of these patients were reviewed and correlated with clinical data. We identified four patterns of thalamus lesions: (a) fluid attenuated inversion recovery-hyperintense pulvinar lesions (20 patients), as known from status epilepticus. Ten patients in this group had a status epilepticus. Among the remaining patients, three had frequent seizures and seven had sporadic seizures. Twelve patients had follow-up exams for a median of 11 months. The lesions had persisted in 11/12 cases in the last available exam and were reversible in one case only. In seven cases, cone-shaped thalamus atrophy resulted, (b) linear defects in the medial and anterior thalamus (five patients), accompanied by atrophy of the mamillary body and the fornix in patients with chronic epilepsy, (c) extensive bilateral thalamus lesions in two patients with a syndrome caused by mutation in the mitochondrial polymerase gamma, and (d) other thalamus lesions not associated with the seizure disorder (16 patients). The spectrum of thalamus lesions in patients with seizure disorders is wider than previously reported. Postictal pulvinar lesions can persist and may result in thalamic atrophy. Linear defects in the anterior thalamus are associated with limbic system atrophy. (orig.)

  7. Conditional Routing of Information to the Cortex: A Model of the Basal Ganglia’s Role in Cognitive Coordination

    OpenAIRE

    Stocco, Andrea; Lebiere, Christian; Anderson, John R.

    2010-01-01

    The basal ganglia play a central role in cognition and are involved in such general functions as action selection and reinforcement learning. Here, we present a model exploring the hypothesis that the basal ganglia implement a conditional information-routing system. The system directs the transmission of cortical signals between pairs of regions by manipulating separately the selection of sources and destinations of information transfers. We suggest that such a mechanism provides an account f...

  8. Basal Cell Carcinoma (BCC)

    Science.gov (United States)

    ... epithelioma, is the most common form of skin cancer. Basal cell carcinoma usually occurs on sun-damaged skin, especially ... other health issues. Infiltrating or morpheaform basal cell carcinomas: Infiltrating basal cell carcinomas can be more aggressive and locally destructive ...

  9. Neuroaxonal dystrophy in aging human sympathetic ganglia.

    OpenAIRE

    Schmidt, R.E.; Chae, H. Y.; Parvin, C. A.; Roth, K A

    1990-01-01

    Autonomic dysfunction is an increasingly recognized problem in aging animals and man. The pathologic changes that produce autonomic dysfunction in human aging are largely unknown; however, in experimental animal models specific pathologic changes have been found in selected sympathetic ganglia. To address whether similar neuropathologic changes occur in aging humans, the authors have examined paravertebral and prevertebral sympathetic ganglia from a series of 56 adult autopsied nondiabetic pa...

  10. Differential developmental strategies by Sonic hedgehog in thalamus and hypothalamus.

    Science.gov (United States)

    Zhang, Yuanfeng; Alvarez-Bolado, Gonzalo

    2016-09-01

    The traditional concept of diencephalon (thalamus plus hypothalamus) and with it the entire traditional subdivision of the developing neural tube are being challenged by novel insights obtained by mapping the expression of key developmental genes. A model in which the hypothalamus is placed in the most rostral portion of the neural tube, followed caudally by a diencephalon formed by prethalamus, thalamus and pretectum has been proposed. The adult thalamus and hypothalamus are quite unlike each other in connectivity and functions. Here we review work on the role of the secreted morphogen protein Sonic hedgehog (Shh) in the developing diencephalon and hypothalamic region to show how different these two regions are also from this point of view. Shh from the prechordal plate (PCP) induces and patterns the hypothalamus but there is no evidence that this role is fulfilled by a morphogen gradient. Later, the hypothalamic primordium itself expresses Shh and a large part of the hypothalamus belongs to the Shh lineage, including the ventral domains. Neural Shh is necessary to complete the specification (lateral hypothalamus), differentiation and growth of the hypothalamus. Although Gli2A is the major effector of Shh in this region, hypothalamic specification also depends on the suppression of Gli3R by Shh secreted by the PCP as well as the neuroepithelium. The thalamus is patterned by an Shh morphogen gradient originated in the ZLI following similar mechanisms to those in the spinal cord. The thalamus itself does not belong to the Shh lineage. Gli2A is necessary for appropriate growth and specification of the thalamic nuclei, to the exception of the medial and intralaminar groups (limbic-related), whose development depends on Gli3R. Beyond specification and patterning, the scarce data available about cell sorting and aggregation in these two regions shows key differences between them as well. In summary, not only expression patterns but also developmental mechanisms support

  11. Idea of a new anatomy of the thalamus.

    Science.gov (United States)

    Mehler, W. R.

    1971-01-01

    Review of some of the advances in knowledge about the thalamus and various aspects of thalamic function and organization accomplished during the last 15 years with the aid of improved neurophysiological research methods. Special attention is given to cytoarchitectural differentiations which, heretofore of little more than descriptive interest, have gradually begun to be clarified in terms of their functional significance.

  12. Spatially distributed encoding of covert attentional shifts in human thalamus

    DEFF Research Database (Denmark)

    Hulme, Oliver J; Whiteley, Louise Emma; Shipp, Stewart

    2010-01-01

    Spatial attention modulates signal processing within visual nuclei of the thalamus--but do other nuclei govern the locus of attention in top-down mode? We examined functional MRI (fMRI) data from three subjects performing a task requiring covert attention to 1 of 16 positions in a circular array...

  13. Rapid feedback processing in human nucleus accumbens and motor thalamus

    NARCIS (Netherlands)

    Schüller, T.; Gründler, T.O.J.; Jocham, G.; Klein, T.A.; Timmermann, L.; Visser-Vandewalle, V.E.R.M.; Kuhn, J.

    2015-01-01

    The nucleus accumbens (NAcc) and thalamus are integral parts in models of feedback processing. Deep brain stimulation (DBS) has been successfully employed to alleviate symptoms of psychiatric conditions including obsessive-compulsive disorder (OCD) and Tourette's syndrome (TS). Common target structu

  14. PRENATAL EXPOSURE TO ETHANOL AFFECTS POSTNATAL NEUROGENESIS IN THALAMUS

    OpenAIRE

    Mooney, Sandra M.; Miller, Michael W.

    2010-01-01

    The number of neurons in the ventrobasal thalamus (VB) in the adolescent rat is unaffected by prenatal exposure to ethanol. This is in sharp contrast to other parts of the trigeminal-somatosensory system which exhibit 30–35% fewer neurons after prenatal ethanol exposure. The present study tested the hypothesis that prenatal ethanol exposure affects dynamic changes in the numbers of VB neurons; such changes reflect the sum of cell proliferation and death. Neuronal number in the VB was determin...

  15. Vasomotion and neurovascular coupling in the visual thalamus in vivo.

    OpenAIRE

    Rivadulla C, deLabra C, Grieve KL, Cudeiro J

    2011-01-01

    Spontaneous contraction and relaxation of arteries (and in some instances venules) has been termed vasomotion and has been observed in an extensive variety of tissues and species. However, its functions and underlying mechanisms are still under discussion. We demonstrate that in vivo spectrophotometry, measured simultaneously with extracellular recordings at the same locations in the visual thalamus of the cat, reveals vasomotion, measured as an oscillation (0.14hz) in the recorded oxyhemoglo...

  16. The paraventricular thalamus controls a central amygdala fear circuit

    OpenAIRE

    Penzo, Mario A.; Robert, Vincent; Tucciarone, Jason; Bundel, Dimitri De; Wang, Minghui; Van Aelst, Linda; Darvas, Martin; Parada, Luis F.; Palmiter, Richard; He, Miao; Huang, Z. Josh; Li, Bo

    2015-01-01

    Appropriate responses to an imminent threat brace us for adversities. The ability to sense and predict threatening or stressful events is essential for such adaptive behavior. In the mammalian brain, one putative stress sensor is the paraventricular nucleus of the thalamus (PVT), an area that is readily activated by both physical and psychological stressors 1-3 . However, the role of PVT in the establishment of adaptive behavioral responses remains unclear. Here we show in mice that PVT regul...

  17. The role of the thalamus in ADHD symptomatology and treatment.

    Science.gov (United States)

    Bailey, Teresa; Joyce, Arthur

    2015-01-01

    Attention-deficit hyperactivity disorder (ADHD) is a chronic disorder with symptoms of inattention and impulsivity that partially remit with age. A review of longitudinal studies of children and adolescents with ADHD showed that the majority will have continued cognitive and functional impairments into adulthood. The thalamus likely plays a prominent role in ADHD symptomatology, based on evidence that the thalamus generates waking-state electroencephalography (EEG) rhythms along with extensive thalamic neural circuitry connections with cortical and subcortical areas. Research demonstrates a specific abnormality in the thalamic pulvinar nucleus in ADHD populations. The thalamus can also play a role in ADHD treatment, based on solid evidence that both animals and humans can learn to self-regulate EEG oscillations. Given the underarousal and sleep disturbance commonly seen in ADHD, along with data that indicate an increased dosage of ADHD medication may improve behavioral control at a cost of lowered cognitive functioning, further investigation of the role for self-regulation through EEG training is warranted. PMID:25748775

  18. In vivo chronic nicotine exposure differentially and reversibly affects upregulation and stoichiometry of α4β2 nicotinic receptors in cortex and thalamus.

    Science.gov (United States)

    Fasoli, F; Moretti, M; Zoli, M; Pistillo, F; Crespi, A; Clementi, F; Mc Clure-Begley, T; Marks, M J; Gotti, C

    2016-09-01

    Studies with heterologous expression systems have shown that the α4β2 nicotinic acetylcholine receptor (nAChR) subtype can exist in two stoichiometries (with two [(α4)2(β2)3] or three [(α4)3(β2)2] copies of the α subunit in the receptor pentamer) which have different pharmacological and functional properties and are differently regulated by chronic nicotine treatment. However, the effects of nicotine treatment in vivo on native α4β2 nAChR stoichiometry are not well known. We investigated in C57BL/6 mice the in vivo effect of 14-day chronic nicotine treatment and subsequent withdrawal, on the subunit expression and β2/α4 subunit ratio of (3)H-epibatidine labeled α4β2*-nAChR in total homogenates of cortex and thalamus. We found that in basal conditions the ratio of the β2/α4 subunit in the cortex and thalamus is different indicating a higher proportion in receptors with (α4)2(β2)3 subunit stoichiometry in the thalamus. For cortex exposure to chronic nicotine elicited an increase in receptor density measured by (3)H-epibatidine binding, an increase in the α4 and β2 protein levels, and an increase in β2/α4 subunit ratio, that indicates an increased proportion of receptors with the (α4)2(β2)3 stoichiometry. For thalamus we did not find a significant increase in receptor density, α4 and β2 protein levels, or changes in β2/α4 subunit ratio. All the changes elicited by chronic nicotine in cortex were transient and returned to basal levels with an average half-life of 2.8 days following nicotine withdrawal. These data suggest that chronic nicotine exposure in vivo favors increased assembly of α4β2 nAChR containing three β2 subunits. A greater change in stoichiometry was observed for cortex (which has relatively low basal expression of (α4)2(β2)3 nAChR) than in thalamus (which has a relatively high basal expression of (α4)2(β2)3 nAChR). PMID:27157710

  19. Nevoid Basal Cell Carcinoma Syndrome

    Science.gov (United States)

    ... Nevoid Basal Cell Carcinoma Syndrome Request Permissions Nevoid Basal Cell Carcinoma Syndrome Approved by the Cancer.Net Editorial Board , 04/2016 What is Nevoid Basal Cell Carcinoma Syndrome? Nevoid Basal Cell Carcinoma Syndrome (NBCCS) is ...

  20. Basal Reinforced Piled Embankments

    NARCIS (Netherlands)

    Van Eekelen, S.J.M.

    2015-01-01

    A basal reinforced piled embankment consists of a reinforced embankment on a pile foundation. The reinforcement consists of one or more horizontal layers of geosynthetic reinforcement (GR) installed at the base of the embankment. The design of the GR is the subject of this thesis. A basal reinforce

  1. ACETYLCHOLINESTERASE HISTOCHEMISTRY OF THE THALAMUS IN THE PRIMATE

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To observe the distribution of acetylcholinesterase activity in the thalamus of the monkey.Methods Histochemical method was used to detect the acetylcholinesterase activity in the thalamus.Results Acetylcholinesterase was found to be inhomogeneous distribution in the primate thalamus and to reveal previously uncovered inhomogeneity within certain thalamic nuclei and their subdivisions. The medial, ventral and posterior nuclear groups displayed markedly uneven acetylcholinesterase reaction.In the mediodorsal nucleus,three distinct sbudivisions were revealed by acetylcholinesterase histochemistry, medial magnocellular part, ventral sector of central parvicellular part and dorsolateral sector of lateral pars multiformity showed weak, moderate and strong acetylcholinesterase activity, respectively. In the ventral nuclear group, acetylcholinesterase histochemistry was strong in the medial part of ventral posterior nucleus, moderate in the magnocellular part of ventral anterior, caudal, medial, oral and pars postrema parts of ventral lateral nucleus, as well as lateral part of ventral posterior nucleus, poor and weak in the inferior part of ventral posterior nucleus, par compacta of the medial part of ventral posterior nucleus and parvicellular part of ventral anterior nucleus. In the pulvinar nucleus, acetylcholinesterase reaction ranged from weak, moderate to strong in the parts of the oral, medial and lateral, as well as inferior of this nucleus, respectively. Regional variations of acetylcholinesterase activity within the thalamic nuclei and their subdivisions can help to identify them by acetylcholinesterase histochemistry. In addition, the dark patches of strong acetylcholinesterase activity contrasting with a lighter surrounding matrix were revealed within the parvicellular part and pars multiformis of mediodorsal nucleus, paracentral nucleus, central lateral nucleus, pars postrema part of ventral lateral nucleus and medial habenula nucleus, as well as

  2. Cocaine-Induced Synaptic Alterations in Thalamus to Nucleus Accumbens Projection.

    Science.gov (United States)

    Neumann, Peter A; Wang, Yicun; Yan, Yijin; Wang, Yao; Ishikawa, Masago; Cui, Ranji; Huang, Yanhua H; Sesack, Susan R; Schlüter, Oliver M; Dong, Yan

    2016-08-01

    Exposure to cocaine induces addiction-associated behaviors partially through remodeling neurocircuits in the nucleus accumbens (NAc). The paraventricular nucleus of thalamus (PVT), which projects to the NAc monosynaptically, is activated by cocaine exposure and has been implicated in several cocaine-induced emotional and motivational states. Here we show that disrupting synaptic transmission of select PVT neurons with tetanus toxin activated via retrograde trans-synaptic transport of cre from NAc efferents decreased cocaine self-administration in rats. This projection underwent complex adaptations after self-administration of cocaine (0.75 mg/kg/infusion; 2 h/d × 5 d, 1d overnight training). Specifically, 1d after cocaine self-administration, we observed increased levels of AMPA receptor (AMPAR)-silent glutamatergic synapses in this projection, accompanied by a decreased ratio of AMPAR-to-NMDA receptor (NMDAR)-mediated EPSCs. Furthermore, the decay kinetics of NMDAR EPSCs was significantly prolonged, suggesting insertion of new GluN2B-containing NMDARs to PVT-to-NAc synapses. After 45-d withdrawal, silent synapses within this projection returned to the basal levels, accompanied by a return of the AMPAR/NMDAR ratio and NMDAR decay kinetics to the basal levels. In amygdala and infralimbic prefrontal cortical projections to the NAc, a portion of cocaine-generated silent synapses becomes unsilenced by recruiting calcium-permeable AMPARs (CP-AMPARs) after drug withdrawal. However, the sensitivity of PVT-to-NAc synapses to CP-AMPAR-selective antagonists was not changed after withdrawal, suggesting that CP-AMPAR trafficking is not involved in the evolution of cocaine-generated silent synapses within this projection. Meanwhile, the release probability of PVT-to-NAc synapses was increased after short- and long-term cocaine withdrawal. These results reveal complex and profound alterations at PVT-to-NAc synapses after cocaine exposure and withdrawal. PMID:27074816

  3. Segmentation of thalamus from MR images via task-driven dictionary learning

    Science.gov (United States)

    Liu, Luoluo; Glaister, Jeffrey; Sun, Xiaoxia; Carass, Aaron; Tran, Trac D.; Prince, Jerry L.

    2016-03-01

    Automatic thalamus segmentation is useful to track changes in thalamic volume over time. In this work, we introduce a task-driven dictionary learning framework to find the optimal dictionary given a set of eleven features obtained from T1-weighted MRI and diffusion tensor imaging. In this dictionary learning framework, a linear classifier is designed concurrently to classify voxels as belonging to the thalamus or non-thalamus class. Morphological post-processing is applied to produce the final thalamus segmentation. Due to the uneven size of the training data samples for the non-thalamus and thalamus classes, a non-uniform sampling scheme is pro- posed to train the classifier to better discriminate between the two classes around the boundary of the thalamus. Experiments are conducted on data collected from 22 subjects with manually delineated ground truth. The experimental results are promising in terms of improvements in the Dice coefficient of the thalamus segmentation overstate-of-the-art atlas-based thalamus segmentation algorithms.

  4. The role of exercise in facilitating basal ganglia function in Parkinson’s disease

    OpenAIRE

    Petzinger, Giselle M.; Fisher, Beth E.; Akopian, Garnik; Holschneider, Daniel P.; Wood, Ruth; Walsh, John P.; Lund, Brett; Meshul, Charles; Vuckovic, Marta; Jakowec, Michael W.

    2011-01-01

    Epidemiological and clinical studies have suggested that exercise is beneficial for patients with Parkinson’s disease (PD). Through research in normal (noninjured) animals, neuroscientists have begun to understand the mechanisms in the brain by which behavioral training and exercise facilitates improvement in motor behavior through modulation of neuronal function and structure, called experience-dependent neuroplasticity. Recent studies are beginning to reveal molecules and downstream signali...

  5. DISCONNECTION OF A BASAL GANGLIA CIRCUIT IN JUVENILE SONGBIRDS ATTENUATES THE SPECTRAL DIFFERENTIATION OF SONG SYLLABLES

    OpenAIRE

    Elliott, Kevin C.; Wu, Wei; Bertram, Richard; Johnson, Frank

    2013-01-01

    Similar to language acquisition by human infants, juvenile male zebra finches (Taeniopygia guttata) imitate an adult (tutor) song by transitioning from repetitive production of one or two undifferentiated protosyllables to the sequential production of a larger and spectrally heterogeneous set of syllables. The primary motor region that controls learned song is driven by a confluence of input from two pre-motor pathways: a posterior pathway that encodes the adult song syllables and an anterior...

  6. Hyporesponsive Reward Anticipation in the Basal Ganglia following Severe Institutional Deprivation Early in Life

    Science.gov (United States)

    Mehta, Mitul A.; Gore-Langton, Emma; Golembo, Nicole; Colvert, Emma; Williams, Steven C. R.; Sonuga-Barke, Edmund

    2010-01-01

    Severe deprivation in the first few years of life is associated with multiple difficulties in cognition and behavior. However, the brain basis for these difficulties is poorly understood. Structural and functional neuroimaging studies have implicated limbic system structures as dysfunctional, and one functional imaging study in a heterogeneous…

  7. Motion and Emotion : Functional In Vivo Analyses of the Mouse Basal Ganglia

    OpenAIRE

    Arvidsson, Emma

    2014-01-01

    A major challenge in the field of neuroscience is to link behavior with specific neuronal circuitries and cellular events. One way of facing this challenge is to identify unique cellular markers and thus have the ability to, through various mouse genetics tools, mimic, manipulate and control various aspects of neuronal activity to decipher their correlation to behavior. The Vesicular Glutamate Transporter 2 (VGLUT2) packages glutamate into presynaptic vesicles for axonal terminal release. In ...

  8. Severity of Dysfluency Correlates with Basal Ganglia Activity in Persistent Developmental Stuttering

    Science.gov (United States)

    Giraud, Anne-Lise; Neumann, Katrin; Bachoud-Levi, Anne-Catherine; von Gudenberg, Alexander W.; Euler, Harald A.; Lanfermann, Heinrich; Preibisch, Christine

    2008-01-01

    Previous studies suggest that anatomical anomalies [Foundas, A. L., Bollich, A. M., Corey, D. M., Hurley, M., & Heilman, K. M. (2001). "Anomalous anatomy of speech-language areas in adults with persistent developmental stuttering." "Neurology," 57, 207-215; Foundas, A. L., Corey, D. M., Angeles, V., Bollich, A. M., Crabtree-Hartman, E., & Heilman,…

  9. Interacting cortical and basal ganglia networks underlying finding and tapping to the musical beat.

    Science.gov (United States)

    Kung, Shu-Jen; Chen, Joyce L; Zatorre, Robert J; Penhune, Virginia B

    2013-03-01

    Humans are able to find and tap to the beat of musical rhythms varying in complexity from children's songs to modern jazz. Musical beat has no one-to-one relationship with auditory features-it is an abstract perceptual representation that emerges from the interaction between sensory cues and higher-level cognitive organization. Previous investigations have examined the neural basis of beat processing but have not tested the core phenomenon of finding and tapping to the musical beat. To test this, we used fMRI and had musicians find and tap to the beat of rhythms that varied from metrically simple to metrically complex-thus from a strong to a weak beat. Unlike most previous studies, we measured beat tapping performance during scanning and controlled for possible effects of scanner noise on beat perception. Results showed that beat finding and tapping recruited largely overlapping brain regions, including the superior temporal gyrus (STG), premotor cortex, and ventrolateral PFC (VLPFC). Beat tapping activity in STG and VLPFC was correlated with both perception and performance, suggesting that they are important for retrieving, selecting, and maintaining the musical beat. In contrast BG activity was similar in all conditions and was not correlated with either perception or production, suggesting that it may be involved in detecting auditory temporal regularity or in associating auditory stimuli with a motor response. Importantly, functional connectivity analyses showed that these systems interact, indicating that more basic sensorimotor mechanisms instantiated in the BG work in tandem with higher-order cognitive mechanisms in PFC.

  10. The role of basal ganglia and cerebellum in motor learning. A computational model

    OpenAIRE

    Senatore, Rosa

    2012-01-01

    2010 - 2011 Our research activity investigates the computational processes underlying the execution of complex sequences of movements and aims at understanding how different levels of the nervous system interact and contribute to the gradual improvement of motor performance during learning. Many research areas, from neuroscience to engineering, investigate, from different perspectives and for diverse purposes, the processes that allow humans to efficiently perform skilled movem...

  11. Structural parcellation of the thalamus using shortest-path tractography

    DEFF Research Database (Denmark)

    Kasenburg, Niklas; Darkner, Sune; Hahn, Ute;

    2016-01-01

    We demonstrate how structural parcellation can be implemented using shortest-path tractography, thereby addressing some of the shortcomings of the conventional approaches. In particular, our algorithm quantifies, via p-values, the confidence that a voxel in the parcellated region is connected...... to each cortical target region. Calculation of these statistical measures is derived from a rank-based test on the histogram of tract-based scores from all the shortest paths found between the source voxel and each voxel within the target region. Using data from the Human Connectome Project, we show...... that parcellation of the thalamus results in p-value maps that are spatially coherent across subjects. Comparing to the state-of-the-art parcellation of Behrens et al. [1], we observe some agreement, but the soft segmentation exhibits better stability for voxels connected to multiple target regions....

  12. Thalamus segmentation from MP2RAGE: a comparative study

    DEFF Research Database (Denmark)

    Eskildsen, Simon Fristed; Næss-Schmidt, Erhard; Blicher, Jakob;

    MPRAGE images with different inversion times to construct an MP2RAGE image, free of B1 bias problems [1]. Since this so-called MP2RAGE sequence is independent of B1 as well as M0 and T2*, the T1 image contrast is improved but also different from conventional MPRAGE images. Thus, existing segmentation...... methods may not work well with this new sequence. In this study we tested three different automatic methods for the important task of segmenting the thalamus from human brain MP2RAGE images. Methods: Twelve healthy control subjects (age range 19 – 38 years, two females) were scanned with a whole brain MP2...... the thalami of all subjects using in-house software. Images were separately processed with Freesurfer (version 5.3) [2] and a recent processing pipeline [3], where anatomical structures are segmented with ANIMAL [4]. Finally, a non-local means patch based segmentation method (SNIPE) was applied using...

  13. Contributions of Volumetrics of the Hippocampus and Thalamus to Verbal Memory in Temporal Lobe Epilepsy Patients

    Science.gov (United States)

    Stewart, Christopher C.; Griffith, H. Randall; Okonkwo, Ozioma C.; Martin, Roy C.; Knowlton, Robert K.; Richardson, Elizabeth J.; Hermann, Bruce P.; Seidenberg, Michael

    2009-01-01

    Recent theories have posited that the hippocampus and thalamus serve distinct, yet related, roles in episodic memory. Whereas the hippocampus has been implicated in long-term memory encoding and storage, the thalamus, as a whole, has been implicated in the selection of items for subsequent encoding and the use of retrieval strategies. However,…

  14. Thalamus parcellation using multi-modal feature classification and thalamic nuclei priors

    Science.gov (United States)

    Glaister, Jeffrey; Carass, Aaron; Stough, Joshua V.; Calabresi, Peter A.; Prince, Jerry L.

    2016-03-01

    Segmentation of the thalamus and thalamic nuclei is useful to quantify volumetric changes from neurodegenerative diseases. Most thalamus segmentation algorithms only use T1-weighted magnetic resonance images and current thalamic parcellation methods require manual interaction. Smaller nuclei, such as the lateral and medial geniculates, are challenging to locate due to their small size. We propose an automated segmentation algorithm using a set of features derived from diffusion tensor image (DTI) and thalamic nuclei location priors. After extracting features, a hierarchical random forest classifier is trained to locate the thalamus. A second random forest classifies thalamus voxels as belonging to one of six thalamic nuclei classes. The proposed algorithm was tested using a leave-one-out cross validation scheme and compared with state-of-the-art algorithms. The proposed algorithm has a higher Dice score compared to other methods for the whole thalamus and several nuclei.

  15. Vasomotion and neurovascular coupling in the visual thalamus in vivo.

    Directory of Open Access Journals (Sweden)

    Casto Rivadulla

    Full Text Available Spontaneous contraction and relaxation of arteries (and in some instances venules has been termed vasomotion and has been observed in an extensive variety of tissues and species. However, its functions and underlying mechanisms are still under discussion. We demonstrate that in vivo spectrophotometry, measured simultaneously with extracellular recordings at the same locations in the visual thalamus of the cat, reveals vasomotion, measured as an oscillation (0.14 hz in the recorded oxyhemoglobin (OxyHb signal, which appears spontaneously in the microcirculation and can last for periods of hours. During some non-oscillatory periods, maintained sensory stimulation evokes vasomotion lasting ~30s, resembling an adaptive vascular phenomenon. This oscillation in the oxyhaemoblobin signal is sensitive to pharmacological manipulation: it is inducible by chloralose anaesthesia and it can be temporarily blocked by systemic administration of adrenaline or acetylcholine (ACh. During these oscillatory periods, neurovascular coupling (i.e. the relationship between local neural activity and the rate of blood supply to that location appears significantly altered. This raises important questions with regard to the interpretation of results from studies currently dependent upon a linear relationship between neural activity and blood flow, such as neuroimaging.

  16. Cross-frequency Coupling Within and Between the Human Thalamus and Neocortex

    Directory of Open Access Journals (Sweden)

    Thomas H B Fitzgerald

    2013-03-01

    Full Text Available There is currently growing interest in, and increasing evidence for, cross-frequency interactions between electrical field oscillations in the brains of various organisms. A number of theories have linked such interactions to crucial features of neuronal function and cognition. In mammals, these interactions have mostly been reported in the neocortex and hippocampus, and it remains unexplored whether similar patterns of activity occur in the thalamus, and between the thalamus and neocortex Here we use data recorded from patients undergoing thalamic deep-brain stimulation for epilepsy to demonstrate the existence and prevalence, across a range of frequencies, of both phase-amplitude and amplitude-amplitude coupling both within the thalamus and prefrontal cortex, and between them. These cross-frequency interactions may play an important role in local processing within the thalamus and neocortex, as well as information transfer between them.

  17. The tale of the three brothers - Shh, Wnt and Fgf during development of the thalamus

    Directory of Open Access Journals (Sweden)

    Anja IH Hagemann

    2012-05-01

    Full Text Available The thalamic complex is an essential part of the brain that requires a combination of specialized activities to attain its final complexity. In the following review we will describe the induction process of the mid-diencephalic organizer (MDO where three different signaling pathways merge: Wnt, Shh and Fgf. Here, we dissect the function of each signaling pathway in the thalamus in chronological order of their appearance. First we describe the Wnt mediated induction of the MDO and compartition of the caudal forebrain, then the Shh mediated determination of proneural gene expression before discussing recent progress in characterizing Fgf function during thalamus development. Then, we focus on transcription factors, which are regulated by these pathways and which play a pivotal role in neurogenesis in the thalamus. The three signaling pathways act together in a strictly regulated chronology to orchestrate the development of the entire thalamus.

  18. Involvement of dorsal root ganglia in Fabry's disease.

    OpenAIRE

    Gadoth, N; Sandbank, U.

    1983-01-01

    Bouts of shooting pain along the extremities are common in the early stages of Fabry's disease. No pathological explanation has been advanced to clarify the mechanism of such pain. In the present case neuronal storage of glycolipid was confined to dorsal root ganglia neurones only. It is suggested that this may explain the shooting pain in Fabry's disease. In hereditary sensory radicular neuropathy, familial dysautonomia, and tabes dorsalis, changes in dorsal root ganglia cells cause similar ...

  19. Orbito-frontal cortex and thalamus volumes in obsessive-compulsive disorder before and after pharmacotherapy.

    Science.gov (United States)

    Atmaca, Murad; Mermi, Osman; Yildirim, Hanefi; Gurok, M Gurkan

    2016-09-01

    In the present study, we focused on the key brain regions, OFC and thalamus, to investigate the roles of antiobsessional agents on volume changes of these brain regions after 12 weeks of anti-obsessional treatment in patients with obsessive-compulsive disorder (OCD). Fourteen patients with OCD and the same number of healthy controls were included in the study. At baseline, the volumes of the OFC and thalamus were compared by using magnetic resonance imaging (MRI) between groups. The volumes of OFC and thalamus were evaluated before and after the anti-obsessional drug treatment solely in the patient group. Our study revealed that thalamus volumes were reduced statistically significantly throughout the treatment period. However, we found that OFC volumes did not change statistically significantly throughout the treatment period. In summary, our study found that anti-obsessional drug treatment had an effect on thalamus volumes throughout the treatment period for both sides but not on OFC volumes. However, future studies with larger sample are required. PMID:26311393

  20. Thalamus-derived molecules promote survival and dendritic growth of developing cortical neurons.

    Science.gov (United States)

    Sato, Haruka; Fukutani, Yuma; Yamamoto, Yuji; Tatara, Eiichi; Takemoto, Makoto; Shimamura, Kenji; Yamamoto, Nobuhiko

    2012-10-31

    The mammalian neocortex is composed of various types of neurons that reflect its laminar and area structures. It has been suggested that not only intrinsic but also afferent-derived extrinsic factors are involved in neuronal differentiation during development. However, the role and molecular mechanism of such extrinsic factors are almost unknown. Here, we attempted to identify molecules that are expressed in the thalamus and affect cortical cell development. First, thalamus-specific molecules were sought by comparing gene expression profiles of the developing rat thalamus and cortex using microarrays, and by constructing a thalamus-enriched subtraction cDNA library. A systematic screening by in situ hybridization showed that several genes encoding extracellular molecules were strongly expressed in sensory thalamic nuclei. Exogenous and endogenous protein localization further demonstrated that two extracellular molecules, Neuritin-1 (NRN1) and VGF, were transported to thalamic axon terminals. Application of NRN1 and VGF to dissociated cell culture promoted the dendritic growth. An organotypic slice culture experiment further showed that the number of primary dendrites in multipolar stellate neurons increased in response to NRN1 and VGF, whereas dendritic growth of pyramidal neurons was not promoted. These molecules also increased neuronal survival of multipolar neurons. Taken together, these results suggest that the thalamus-specific molecules NRN1 and VGF play an important role in the dendritic growth and survival of cortical neurons in a cell type-specific manner. PMID:23115177

  1. Neurodevelopment. Parasympathetic ganglia derive from Schwann cell precursors.

    Science.gov (United States)

    Espinosa-Medina, I; Outin, E; Picard, C A; Chettouh, Z; Dymecki, S; Consalez, G G; Coppola, E; Brunet, J-F

    2014-07-01

    Neural crest cells migrate extensively and give rise to most of the peripheral nervous system, including sympathetic, parasympathetic, enteric, and dorsal root ganglia. We studied how parasympathetic ganglia form close to visceral organs and what their precursors are. We find that many cranial nerve-associated crest cells coexpress the pan-autonomic determinant Paired-like homeodomain 2b (Phox2b) together with markers of Schwann cell precursors. Some give rise to Schwann cells after down-regulation of PHOX2b. Others form parasympathetic ganglia after being guided to the site of ganglion formation by the nerves that carry preganglionic fibers, a parsimonious way of wiring the pathway. Thus, cranial Schwann cell precursors are the source of parasympathetic neurons during normal development. PMID:24925912

  2. Thalamus Degeneration and Inflammation in Two Distinct Multiple Sclerosis Animal Models.

    Science.gov (United States)

    Wagenknecht, Nina; Becker, Birte; Scheld, Miriam; Beyer, Cordian; Clarner, Tim; Hochstrasser, Tanja; Kipp, Markus

    2016-09-01

    There is a broad consensus that multiple sclerosis (MS) represents more than an inflammatory disease: it harbors several characteristic aspects of a classical neurodegenerative disorder, i.e., damage to axons, synapses, and nerve cell bodies. While several accepted paraclinical methods exist to monitor the inflammatory-driven aspects of the disease, techniques to monitor progression of early and late neurodegeneration are still in their infancy and have not been convincingly validated. It was speculated that the thalamus with its multiple reciprocal connections is sensitive to inflammatory processes occurring in different brain regions, thus acting as a "barometer" for diffuse brain parenchymal damage in MS. To what extent the thalamus is affected in commonly applied MS animal models is, however, not known. In this article we describe direct and indirect damage to the thalamus in two distinct MS animal models. In the cuprizone model, we observed primary oligodendrocyte stress which is followed by demyelination, microglia/astrocyte activation, and acute axonal damage. These degenerative cuprizone-induced lesions were found to be more severe in the lateral compared to the medial part of the thalamus. In MOG35-55-induced EAE, in contrast, most parts of the forebrain, including the thalamus were not directly involved in the autoimmune attack. However, important thalamic afferent fiber tracts, such as the spinothalamic tract were inflamed and demyelinated on the spinal cord level. Quantitative immunohistochemistry revealed that this spinal cord inflammatory-demyelination is associated with neuronal loss within the target region of the spinothalamic tract, namely the sensory ventral posterolateral nucleus of the thalamus. This study highlights the possibility of trans-neuronal degeneration as one mechanism of secondary neuronal damage in MS. Further studies are now warranted to investigate involved cell types and cellular mechanisms. PMID:27491786

  3. The histaminergic system in human thalamus: correlation of innervation to receptor expression.

    Science.gov (United States)

    Jin, C Y; Kalimo, H; Panula, Pertti

    2002-04-01

    The mRNA expression of three histamine receptors (H1, H2 and H3) and H1 and H3 receptor binding were mapped and quantified in normal human thalamus by in situ hybridization and receptor binding autoradiography, respectively. Immunohistochemistry was applied to study the distribution of histaminergic fibres and terminals in the normal human thalamus. mRNAs for all three histamine receptors were detected mainly in the dorsal thalamus, but the expression intensities were different. Briefly, H1 and H3 receptor mRNAs were relatively enriched in the anterior, medial, and part of the lateral nuclei regions; whereas the expression level was much lower in the ventral and posterior parts of the thalamus, and the reticular nucleus. H2 receptor mRNA displayed in general very low expression intensity with slightly higher expression level in the anterior and lateropolar regions. H1 receptor binding was mainly detected in the mediodorsal, ventroposterolateral nuclei, and the pulvinar. H3 receptor binding was detected mainly in the dorsal thalamus, predominantly the periventricular, mediodorsal, and posterior regions. Very high or high histaminergic fibre densities were observed in the midline nuclear region and other nuclei next to the third ventricle, ventroposterior lateral nucleus and medial geniculate nucleus. In most of the core structures of the thalamus, the fibre density was very low or absent. The results suggest that histamine in human brain regulates tactile and proprioceptory thalamocortical functions through multiple receptors. Also, other, e.g. visual areas and those not making cortical connections expressed histamine receptors and contained histaminergic nerve fibres.

  4. Tracheal occlusion conditioning in conscious rats modulates gene expression profile of medial thalamus

    Directory of Open Access Journals (Sweden)

    Vipa eBernhardt

    2011-05-01

    Full Text Available The thalamus may be the critical brain area involved in sensory gating and the relay of respiratory mechanical information to the cerebral cortex for the conscious awareness of breathing. We hypothesized that respiratory mechanical stimuli in the form of tracheal occlusions would modulate the gene expression profile of the thalamus. Specifically, it was reasoned that conditioning to the respiratory loading would induce a state change in the medial thalamus consistent with a change in sensory gating and the activation of molecular pathways associated with learning and memory. In addition, respiratory loading is stressful and thus should elicit changes in gene expressions related to stress, anxiety, and depression. Rats were instrumented with inflatable tracheal cuffs. Following surgical recovery, they underwent ten days (5 days/week of transient tracheal occlusion conditioning. On day 10, the animals were sacrificed and the brains removed. The medial thalamus was dissected and microarray analysis of gene expression performed. Tracheal obstruction conditioning modulated a total of 661 genes (p < 0.05, log2 fold change ≥ 0.58, 250 genes were down-regulated and 411 up-regulated. There was a significant down-regulation of GAD1, GAD2 and HTR1A, HTR2A genes. CCK, PRKCG, mGluR4, and KCJN9 genes were significantly up-regulated. Some of these genes have been associated with anxiety and depression, while others have been shown to play a role in switching between tonic and burst firing modes in the thalamus and thus may be involved in gating of the respiratory stimuli. Furthermore, gene ontology and pathway analysis showed a significant modulation of learning and memory pathways. These results support the hypothesis that the medial thalamus is involved in the respiratory sensory neural pathway due to the state change of its gene expression profile following repeated tracheal occlusions.

  5. Roles of the auditory midbrain and thalamus in selective phonotaxis in female gray treefrogs (Hyla versicolor).

    Science.gov (United States)

    Endepols, Heike; Feng, Albert S; Gerhardt, H Carl; Schul, Johannes; Walkowiak, Wolfgang

    2003-10-17

    Diencephalic and midbrain auditory nuclei are involved in the processing of auditory communication signals in anurans [Comparative Hearing: Fish and Amphibians, Springer-Verlag, New York, 1999, p. 218], but their exact roles in acoustically guided behavior, such as female phonotaxis, are unclear. To address this question, behavioral experiments were combined with lesions of dorsal thalamic nuclei and the midbrain torus semicircularis. Females were tested in two-alternative-forced-choice phonotactic experiments before and after a defined brain area was lesioned. During phonotactic tests, females had to choose between a "standard" synthetic call and one of three different variants, each of which had a single acoustic property (pulse rate, pulse rise-time, sound spectrum) that differed from the standard synthetic call. Results showed that dorsomedial thalamus lesions produced little or no effect on phonotaxis. In contrast, superficial and deep thalamus lesions, as well as lesions of the torus semicircularis, significantly decreased the number of phonotactic responses and increased the response time. Superficial thalamus lesions also abolished or reversed preferences for the standard call in the rise-time and sound spectrum tests. This effect is likely to have been caused by an imbalance in the stimulation of the thalamus by the low- and high-frequency pathways because these preferences were not affected in animals with more extensive lesions that included the superficial thalamus. Our data suggest that the torus semicircularis, but not the dorsal thalamus is crucial for phonotaxis in gravid, reproductively active females. Although dorsal thalamic nuclei seem to play a role in spectral sensitivity, they may additionally have motivational or attentional functions that contribute to achieving a state of phonotactic readiness.

  6. COMPARATIVE ANATOMICAL STUDIES ABOUT CHICKEN SUB-BASAL CONNECTIONS

    Directory of Open Access Journals (Sweden)

    CARMEN BERGHES

    2013-07-01

    Full Text Available The studies aimed to describe the nervous formations from the base of the cranium in the hen and domestic duck. These clarifications are necessary in order to disclose some unknown facts regarding this region in the poultry species used preponderantly in laboratory studies of the aviary flu. The vegetative connections from the base of the skull have been studied on 10 poultry specimens, 5 hens and 5 ducks. The animals have been euthanatized using chloroform and a special dye has been injected through the heart in order to achieve a better differentiation of the nervous formations. Dissection was performed under a magnifying glass using instruments adequate to highly fine dissections. Photos and sketches of the dissected pieces have been taken. Nomina Anatomica (2003 was used to describe the observed formations.The studies showed that the cranial cervical ganglia around which is the sub-basal nervous tissue, is located on the border of the occipital hole, at the basis of the temporal pyramid, much deeper than in mammalians; it is better developed in the duck (3-4 mm than in the hen (1-2 mm; the cranial cervical ganglia has the shape of a globe in gallinaceans and it is long in shape in the ducks. A multitude of connecting branches were observed around the lymph node, linking it to the vague nerve, to the hypoglossal nerve, to the glossopharyngeal nerve and to the transversal paravertebral chain which is specific to poultry; an obvious branch detaches from the cranial pole, which is the sub-basal connective, while the cervical connective detaches from the caudal pole, connecting it to the cervical-thoracic lymph node.

  7. Hierarchical Distribution of the Tau Cytoskeletal Pathology in the Thalamus of Alzheimer's Disease Patients

    NARCIS (Netherlands)

    Rueb, Udo; Stratmann, Katharina; Heinsen, Helmut; Del Turco, Domenico; Ghebremedhin, Estifanos; Seidel, Kay; den Dunnen, Wilfred; Korf, Horst-Werner

    2015-01-01

    In spite of considerable progress in neuropathological research on Alzheimer's disease (AD), knowledge regarding the exact pathoanatomical distribution of the tau cytoskeletal pathology in the thalamus of AD patients in the advanced Braak and Braak AD stages V or VI of the cortical cytoskeletal path

  8. Brief Report: Abnormal Association between the Thalamus and Brain Size in Asperger's Disorder

    Science.gov (United States)

    Hardan, Antonio Y.; Girgis, Ragy R.; Adams, Jason; Gilbert, Andrew R.; Melhem, Nadine M.; Keshavan, Matcheri S.; Minshew, Nancy J.

    2008-01-01

    The objective of this study was to examine the relationship between thalamic volume and brain size in individuals with Asperger's disorder (ASP). Volumetric measurements of the thalamus were performed on MRI scans obtained from 12 individuals with ASP (age range: 10-35 years) and 12 healthy controls (age range: 9-33 years). A positive correlation…

  9. The role of the thalamus in schizophrenia from a neuroimaging perspective.

    Science.gov (United States)

    Pergola, Giulio; Selvaggi, Pierluigi; Trizio, Silvestro; Bertolino, Alessandro; Blasi, Giuseppe

    2015-07-01

    The thalamus is a crucial node for brain physiology and part of functional and structural pathways relevant for schizophrenia. Relatively few imaging studies on schizophrenia have focused on this brain region, yet extant evidence supports the association between this brain disorder and thalamic anomalies. Nevertheless, the mechanisms underlying this association remain largely conjectural. Here, we review imaging literature on the relationship between the thalamus and schizophrenia, focusing on critical challenges for future studies, in particular: (i) the anatomical and functional organization of the thalamus in separate nuclei, which are also differently connected with the cortex; (ii) state-dependent variables, which do not allow firm conclusions on the relevance of thalamic correlates as core phenotypes of schizophrenia and (iii) genetic variation, which affects thalamic physiology and may lead to variability of structural and functional patterns. Current evidence from the studies reviewed does not appear conclusive, although the relevance of thalamo-prefrontal interactions clearly emerges. Results from imaging genetics are beginning to cast insight on possible mechanisms of the involvement of the thalamus in schizophrenia. PMID:25616183

  10. Hierarchical Distribution of the Tau Cytoskeletal Pathology in the Thalamus of Alzheimer's Disease Patients.

    Science.gov (United States)

    Rüb, Udo; Stratmann, Katharina; Heinsen, Helmut; Del Turco, Domenico; Ghebremedhin, Estifanos; Seidel, Kay; den Dunnen, Wilfred; Korf, Horst-Werner

    2015-01-01

    In spite of considerable progress in neuropathological research on Alzheimer's disease (AD), knowledge regarding the exact pathoanatomical distribution of the tau cytoskeletal pathology in the thalamus of AD patients in the advanced Braak and Braak AD stages V or VI of the cortical cytoskeletal pathology is still fragmentary. Investigation of serial 100 μm-thick brain tissue sections through the thalamus of clinically diagnosed AD patients with Braak and Braak AD stage V or VI cytoskeletal pathologies immunostained with the anti-tau AT8 antibody, along with the affection of the extraterritorial reticular nucleus of the thalamus, reveals a consistent and severe tau immunoreactive cytoskeletal pathology in the limbic nuclei of the thalamus (e.g., paraventricular, anterodorsal and laterodorsal nuclei, limitans-suprageniculate complex). The thalamic nuclei integrated into the associative networks of the human brain (e.g., ventral anterior and mediodorsal nuclei) are only mildly affected, while its motor precerebellar (ventral lateral nucleus) and sensory nuclei (e.g., lateral and medial geniculate bodies, ventral posterior medial and lateral nuclei, parvocellular part of the ventral posterior medial nucleus) are more or less spared. The highly stereotypical and characteristic thalamic distribution pattern of the AD-related tau cytoskeletal pathology represents an anatomical mirror of the hierarchical topographic distribution of the cytoskeletal pathology in the interconnected regions of the cerebral cortex of AD patients. These pathoanatomical parallels support the pathophysiological concept of a transneuronal spread of the disease process of AD along anatomical pathways. The AD-related tau cytoskeletal pathology in the thalamus most likely contributes substantially to the neuropsychiatric disease symptoms (e.g., dementia), attention deficits, oculomotor dysfunctions, altered non-discriminative aspects of pain experience of AD patients, and the disruption of their

  11. Cardiovascular effects of basal insulins

    Directory of Open Access Journals (Sweden)

    Mannucci E

    2015-07-01

    Full Text Available Edoardo Mannucci,1 Stefano Giannini,2 Ilaria Dicembrini1 1Diabetes Agency, Careggi Teaching Hospital, Florence, 2Section of Endocrinology, Department of Biomedical Clinical and Experimental Sciences, University of Florence and Careggi University Hospital, Florence, Italy Abstract: Basal insulin is an important component of treatment for both type 1 and type 2 diabetes. One of the principal aims of treatment in patients with diabetes is the prevention of diabetic complications, including cardiovascular disease. There is some evidence, although controversial, that attainment of good glycemic control reduces long-term cardiovascular risk in both type 1 and type 2 diabetes. The aim of this review is to provide an overview of the potential cardiovascular safety of the different available preparations of basal insulin. Current basal insulin (neutral protamine Hagedorn [NPH], or isophane and basal insulin analogs (glargine, detemir, and the more recent degludec differ essentially by various measures of pharmacokinetic and pharmacodynamic effects in the bloodstream, presence and persistence of peak action, and within-subject variability in the glucose-lowering response. The currently available data show that basal insulin analogs have a lower risk of hypoglycemia than NPH human insulin, in both type 1 and type 2 diabetes, then excluding additional harmful effects on the cardiovascular system mediated by activation of the adrenergic system. Given that no biological rationale for a possible difference in cardiovascular effect of basal insulins has been proposed so far, available meta-analyses of publicly disclosed randomized controlled trials do not show any signal of increased risk of major cardiovascular events between the different basal insulin analogs. However, the number of available cardiovascular events in these trials is very small, preventing any clear-cut conclusion. The results of an ongoing clinical trial comparing glargine and degludec with

  12. Cardiovascular effects of basal insulins.

    Science.gov (United States)

    Mannucci, Edoardo; Giannini, Stefano; Dicembrini, Ilaria

    2015-01-01

    Basal insulin is an important component of treatment for both type 1 and type 2 diabetes. One of the principal aims of treatment in patients with diabetes is the prevention of diabetic complications, including cardiovascular disease. There is some evidence, although controversial, that attainment of good glycemic control reduces long-term cardiovascular risk in both type 1 and type 2 diabetes. The aim of this review is to provide an overview of the potential cardiovascular safety of the different available preparations of basal insulin. Current basal insulin (neutral protamine Hagedorn [NPH], or isophane) and basal insulin analogs (glargine, detemir, and the more recent degludec) differ essentially by various measures of pharmacokinetic and pharmacodynamic effects in the bloodstream, presence and persistence of peak action, and within-subject variability in the glucose-lowering response. The currently available data show that basal insulin analogs have a lower risk of hypoglycemia than NPH human insulin, in both type 1 and type 2 diabetes, then excluding additional harmful effects on the cardiovascular system mediated by activation of the adrenergic system. Given that no biological rationale for a possible difference in cardiovascular effect of basal insulins has been proposed so far, available meta-analyses of publicly disclosed randomized controlled trials do not show any signal of increased risk of major cardiovascular events between the different basal insulin analogs. However, the number of available cardiovascular events in these trials is very small, preventing any clear-cut conclusion. The results of an ongoing clinical trial comparing glargine and degludec with regard to cardiovascular safety will provide definitive evidence. PMID:26203281

  13. The Design of Ubiquitous Learning System with Embedded Ganglia Agent

    Directory of Open Access Journals (Sweden)

    Fu-Chien Kao

    2011-05-01

    Full Text Available This research proposes a context-aware computing ubiquitous learning system architecture design. The system integrates data grid, the ability to perform context-awareness computing, and embedded Ganglia Agent design, structuring an architecture that is able to perform context awareness mobile network, creating a ubiquitous learning environment. The embedded Ganglia Agent could provide context information on system network traffic, the CPU load of the content server, and hard disk capacity, and utilize the information to balance the load of back-end content server, providing a flexible expandability mechanism for the back-end content server. The framework of the proposed ubiquitous learning system that has context-awareness computing ability is consisted of 3 major parts: Learning Management System (LMS, Learning Content Management System (LCMS and the embedded Ganglia Agent (EGA. LMS is responsible for managing the learners basic personal information and studying records, LCMS is responsible for the management and storage of back-end learning contents, and EGA is responsible for the management network traffic, CPU load and hard disk capacity. With the three, the load of the back-end content server could be balanced, offering a flexible mechanism for the expansion of the server.

  14. Dopaminergic receptor agents and the basal ganglia : pharmacological properties and interactions with the GABA-ergic system

    NARCIS (Netherlands)

    Timmerman, Wigerline

    1992-01-01

    In the present series of studies, attention was focussed particularly on dopaminergic D2 receptor compounds, with emphasis on the enantiomers of the potent and selective dopamine D2 receptor agonist N-0437. Drugs that display activity at D2 receptors are of great interest as potentially new therapeu

  15. A novel mutation in TTC19 associated with isolated complex III deficiency, cerebellar hypoplasia, and bilateral basal ganglia lesions.

    Science.gov (United States)

    Melchionda, Laura; Damseh, Nadirah S; Abu Libdeh, Bassam Y; Nasca, Alessia; Elpeleg, Orly; Zanolini, Alice; Ghezzi, Daniele

    2014-01-01

    Isolated complex III (cIII) deficiency is a rare biochemical finding in mitochondrial disorders, mainly associated with mutations in mitochondrial DNA MTCYB gene, encoding cytochrome b, or in assembly factor genes (BCS1L, TTC19, UQCC2, and LYRM7), whereas mutations in nuclear genes encoding cIII structural subunits are extremely infrequent. We report here a patient, a 9 year old female born from first cousin related parents, with normal development till 18 months when she showed unsteady gait with frequent falling down, cognitive, and speech worsening. Her course deteriorated progressively. Brain MRI showed cerebellar vermis hypoplasia and bilateral lentiform nucleus high signal lesions. Now she is bed ridden with tetraparesis and severely impaired cognitive and language functions. Biochemical analysis revealed isolated cIII deficiency in muscle, and impaired respiration in fibroblasts. We identified a novel homozygous rearrangement in TTC19 (c.213_229dup), resulting in frameshift with creation of a premature termination codon (p.Gln77Argfs*30). Western blot analysis demonstrated the absence of TTC19 protein in patient's fibroblasts, while Blue-Native Gel Electrophoresis analysis revealed the presence of cIII-specific assembly intermediates. Mutations in TTC19 have been rarely associated with mitochondrial disease to date, being described in about ten patients with heterogeneous clinical presentations, ranging from early onset encephalomyopathy to adult forms with cerebellar ataxia. Contrariwise, the biochemical defect was a common hallmark in TTC19 mutant patients, confirming the importance of TTC19 in cIII assembly/stability. Therefore, we suggest extending the TTC19 mutational screening to all patients with cIII deficiency, independently from their phenotypes. PMID:25452764

  16. In vivo labelling and axonal transport of monoamine oxidase in the rat basal ganglia using radioactive pargyline

    International Nuclear Information System (INIS)

    The enzyme monoamine oxidase was labelled in the rat striatum or substantia nigra with locally injected radioactive pargyline. The binding was prevented by a pretreatment with non-radioactive pargyline, or with a combination of clorgyline and deprenyl. Most of the MAO labelled with 3H-pargyline was of the B-type, but also some MAO-A was labelled, as shown in rats pretreated with clorgyline or deprenyl separately. Seven days after the injection of (3H)-pargyline into the striatum a significant labelling was observed in the substantia nigra. This labelling was clorgyline sensitive, indicating type A MAO, and was not present when striatal neurons were destroyed with kainic acid. Labelling of the striatum following 3H-pargyline injection into the substantia nigra was also less in kainate intoxicated striata. Damage of nigral dopamine neurons with 6-hydroxydopmaine did not influence the distribution of the label. Thus by using 3H-pargyline, specific labelling and axonal transport of type A MAO in striatal neurons projecting to the substantia nigra was demonstrated. (Author)

  17. Preserved dichotomy but highly irregular and burst discharge in the basal ganglia in alert dystonic rats at rest.

    Science.gov (United States)

    Kumbhare, Deepak; Chaniary, Kunal D; Baron, Mark S

    2015-10-22

    Despite its prevalence, the underlying pathophysiology of dystonia remains poorly understood. Using our novel tri-component classification algorithm, extracellular neuronal activity in the globus pallidus (GP), STN, and the entopeduncular nucleus (EP) was characterized in 34 normal and 25 jaundiced dystonic Gunn rats with their heads restrained while at rest. In normal rats, neurons in each nucleus were similarly characterized by two physiologically distinct types: regular tonic with moderate discharge frequencies (mean rates in GP, STN and EP ranging from 35-41 spikes/s) or irregular at slower frequencies (17-20 spikes/s), with a paucity of burst activity. In dystonic rats, these nuclei were also characterized by two distinct principal neuronal patterns. However, in marked difference, in the dystonic rats, neurons were primarily slow and highly irregular (12-15 spikes/s) or burst predominant (14-17 spikes/s), with maintained modest differences between nuclei. In GP and EP, with increasing severity of dystonia, burstiness was moderately further increased, irregularity mildly further increased, and discharge rates mildly further reduced. In contrast, these features did not appreciably change in STN with worsening dystonia. Findings of a lack of bursting in GP, STN and EP in normal rats in an alert resting state and prominent bursting in dystonic Gunn rats suggest that cortical or other external drive is normally required for bursting in these nuclei and that spontaneous bursting, as seen in dystonia and Parkinson's disease, is reflective of an underlying pathophysiological state. Moreover, the extent of burstiness appears to most closely correlate with the severity of the dystonia. PMID:26210616

  18. [Obsessive-compulsive disorder, a new model of basal ganglia dysfunction? Elements from deep brain stimulation studies].

    Science.gov (United States)

    Haynes, W I A; Millet, B; Mallet, L

    2012-01-01

    Deep brain stimulation was first developed for movement disorders but is now being offered as a therapeutic alternative in severe psychiatric disorders after the failure of conventional therapies. One of such pathologies is obsessive-compulsive disorder. This disorder which associates intrusive thoughts (obsessions) and repetitive irrepressible rituals (compulsions) is characterized by a dysfunction of a cortico-subcortical loop. After having reviewed the pathophysiological evidence to show why deep brain stimulation was an interesting path to take for severe and resistant cases of obsessive-compulsive disorder, we will present the results of the different clinical trials. Finally, we will provide possible mechanisms for the effects of deep brain stimulation in this pathology. PMID:22898561

  19. GENSAT BAC Cre-recombinase driver lines to study the functional organization of cerebral cortical and basal ganglia circuits

    OpenAIRE

    Gerfen, Charles R.; Paletzki, Ronald; Heintz, Nathaniel

    2013-01-01

    Recent development of molecular genetic techniques are rapidly advancing understanding of the functional role of brain circuits in behavior. Critical to this approach is the ability to target specific neuron populations and circuits. The collection of over 250 BAC Cre-recombinase driver lines produced by the GENSAT project provides a resource for such studies. Here we provide characterization of GENSAT BAC-Cre driver lines with expression in specific neuroanatomical pathways within the cerebr...

  20. Integrating cortico-limbic-basal ganglia architectures for learning model-based and model-free navigation strategies

    Directory of Open Access Journals (Sweden)

    Mehdi eKhamassi

    2012-11-01

    Full Text Available Behaviour in spatial navigation is often organised into map-based (place-driven versus map-free (cue-driven strategies; behaviour in operant conditioning research is often organised into goal-directed versus habitual strategies. Here we attempt to unify the two. We review one powerful theory for distinct forms of learning during instrumental conditioning, namely model-based (maintaining a representation of the world and model-free (reacting to immediate stimuli learning algorithms. We extend these lines of argument to propose an alternative taxonomy for spatial navigation, showing how various previously identified strategies can be distinguished as model-based or model-free depending on the usage of information and not on the type of information (e.g. cue vs place. We argue that identifying model-free learning with dorsolateral striatum and model-based learning with dorsomedial striatum could reconcile numerous conflicting results in the spatial navigation literature. From this perspective, we further propose that the ventral striatum plays key roles in the model-building process. We propose that the core of the ventral striatum is positioned to learn the probability of action selection for every transition between states of the world. We further review suggestions that the ventral striatal core and shell are positioned to act as critics contributing to the computation of a reward prediction error for model-free and model-based systems, respectively.

  1. Diffusion tensor imaging reveals thalamus and posterior cingulate cortex abnormalities in internet gaming addicts.

    Science.gov (United States)

    Dong, Guangheng; DeVito, Elise; Huang, Jie; Du, Xiaoxia

    2012-09-01

    Internet gaming addiction (IGA) is increasingly recognized as a widespread disorder with serious psychological and health consequences. Diminished white matter integrity has been demonstrated in a wide range of other addictive disorders which share clinical characteristics with IGA. Abnormal white matter integrity in addictive populations has been associated with addiction severity, treatment response and cognitive impairments. This study assessed white matter integrity in individuals with internet gaming addiction (IGA) using diffusion tensor imaging (DTI). IGA subjects (N = 16) showed higher fractional anisotropy (FA), indicating greater white matter integrity, in the thalamus and left posterior cingulate cortex (PCC) relative to healthy controls (N = 15). Higher FA in the thalamus was associated with greater severity of internet addiction. Increased regional FA in individuals with internet gaming addiction may be a pre-existing vulnerability factor for IGA, or may arise secondary to IGA, perhaps as a direct result of excessive internet game playing.

  2. Nevoid basal cell carcinoma syndrome

    Directory of Open Access Journals (Sweden)

    Kannan Karthiga

    2006-01-01

    Full Text Available Binkley and Johnson first reported this syndrome in 1951. But it was in 1960, Gorlin-Goltz established the association of basal cell epithelioma, jaw cyst and bifid ribs, a combination which is now frequently known as Gorlin-Goltz syndrome as well as Nevoid Basal Cell Carcinoma Syndrome (NBCCS. NBCCS is inherited as an autosomal dominant trait with high penetrance and variable expressivity. NBCCS is characterized by variety of cutaneous, dental, osseous, opthalmic, neurologic and sexual abnormalities. One such case of Gorlin-Goltz syndrome is reported here with good illustrations.

  3. Hyperphosphorylation of tau protein in the ipsilateral thalamus after focal cortical infarction in rats.

    Science.gov (United States)

    Dong, Da-Wei; Zhang, Yu-Sheng; Yang, Wan-Yong; Wang-Qin, Run-Qi; Xu, An-Ding; Ruan, Yi-Wen

    2014-01-16

    Hyperphosphorylation of tau has been considered as an important risk factor for neurodegenerative diseases. It has been found also in the cortex after focal cerebral ischemia. The present study is aimed at investigating changes of tau protein expression in the ipsilateral thalamus remote from the primary ischemic lesion site after distal middle cerebral artery occlusion (MCAO). The number of neurons in the ventroposterior thalamic nucleus (VPN) was evaluated using Nissl staining and neuronal nuclei (NeuN) immunostaining. Total tau and phosphorylated tau at threonine 231 (p-T231-tau) and serine 199 (p-S199-tau) levels, respectively, in the thalamus were measured using immunostaining and immunoblotting. Moreover, apoptosis was detected with terminal deoxynucleotidyl transferase-mediated digoxigenin-dUTP-biotin nick-end labeling (TUNEL) assay. It was found that the numbers of intact neurons and NeuN(+) cells within the ipsilateral VPN were reduced significantly compared with the sham-operated group, but the levels of p-T231-tau and p-S199-tau in the ipsilateral thalamus were increased significantly in rats subjected to ischemia for 3 days, 7 days and 28 days. Furthermore, the number of TUNEL-positive cells was increased in the ipsilateral VPN at 7 days and 28 days after MCAO. Thus, hyperphosphorylated tau protein is observed in ipsilateral thalamus after focal cerebral infarction in this study. Our findings suggest that the expression of hyperphosphorylated tau protein induced by ischemia may be associated with the secondary thalamic damage after focal cortical infarction via an apoptotic pathway.

  4. Extrastriatal binding of [¹²³I]FP-CIT in the thalamus and pons

    DEFF Research Database (Denmark)

    Koch, Walter; Unterrainer, Marcus; Xiong, Guoming;

    2014-01-01

    error) of 8.2 ± 1.3 % for the thalamus and 6.8 ± 2.9 % for the pons was shown. CONCLUSION: The potential to evaluate extrastriatal predominant SERT binding in addition to the striatal DAT in a single imaging session was shown using a large database of [(123)I]FP-CIT scans in healthy controls. For both...

  5. Microstructural differences in the thalamus and thalamic radiations in the congenitally deaf

    Science.gov (United States)

    Lyness, Rebecca C.; Alvarez, I.; Sereno, Martin I.; MacSweeney, Mairéad

    2014-01-01

    There is evidence of both crossmodal and intermodal plasticity in the deaf brain. Here, we investigated whether sub-cortical plasticity, specifically of the thalamus, contributed to this reorganisation. We contrasted diffusion weighted magnetic resonance imaging data from 13 congenitally deaf and 13 hearing participants, all of whom had learnt British Sign Language after 10 years of age. Connectivity based segmentation of the thalamus revealed changes to mean and radial diffusivity in occipital and frontal regions, which may be linked to enhanced peripheral visual acuity, and differences in how visual attention is deployed in the deaf group. Using probabilistic tractography, tracts were traced between the thalamus and its cortical targets, and microstructural measurements were extracted from these tracts. Group differences were found in microstructural measurements of occipital, frontal, somatosensory, motor and parietal thalamo-cortical tracts. Our findings suggest that there is sub-cortical plasticity in the deaf brain, and that white matter alterations can be found throughout the deaf brain, rather than being restricted to, or focussed in the auditory cortex. PMID:24907483

  6. Neo-Timm staining in the thalamus of chronically epileptic rats

    Directory of Open Access Journals (Sweden)

    Hamani C.

    2005-01-01

    Full Text Available The thalamus is an important modulator of seizures and is severely affected in cholinergic models of epilepsy. In the present study, chronically epileptic rats had their brains processed for neo-Timm and acetylcholinesterase two months after the induction of status epilepticus with pilocarpine. Both controls and pilocarpine-treated animals presented neo-Timm staining in the anterodorsal nucleus, laterodorsal nucleus, reticular nucleus, most intralaminar nuclei, nucleus reuniens, and rhomboid nucleus of the thalamus, as well as in the zona incerta. The intensity of neo-Timm staining was similar in control and pilocarpine-treated rats, except for the nucleus reuniens and the rhomboid nucleus, which had a lower intensity of staining in the epileptic group. In animal models of temporal lobe epilepsy, zinc seems to modulate glutamate release and to decrease seizure activity. In this context, a reduction of neo-Timm-stained terminals in the midline thalamus could ultimately result in an increased excitatory activity, not only within its related nuclei, but also in anatomical structures that receive their efferent connections. This might contribute to the pathological substrate observed in chronic pilocarpine-treated epileptic animals.

  7. Functional improvement after motor training is correlated with synaptic plasticity in rat thalamus.

    Science.gov (United States)

    Ding, Yuchuan; Li, Jie; Lai, Qin; Azam, Salman; Rafols, José A; Diaz, Fernando G

    2002-12-01

    The goals of this study were to determine whether functional outcome after motor training in rats was linked to synaptic plasticity in thalamus, and whether the Rota-rod apparatus, widely used to test motor function, could be used as an easy and quantitative motor skill training procedure. Adult female Sprague-Dawley rats (n = 39) were evaluated under three training conditions: 1. Movement requiring balance and coordination skills on Rota-rod; 2. simple exercise on treadmill; 3. nontrained controls. Motor function was evaluated by a series of motor tests (foot fault placing, parallel bar crossing, rope and ladder climbing) before and 14 or 28 days after training procedure. Synaptic strength in brain was assessed by synaptophysin immunocytochemistry. After 14 days of training, Rota-rod-trained animals significantly (p exercises on the treadmill did not show a significantly improved performance on most motor tasks, except for an improvement in foot fault placing. Intensive synaptophysin immunoreactivity was present in the right but not the left mediodorsal and ventromedial nuclei of thalamus in Rota-rod-trained rats at 14 and 28 days, and in treadmill-trained rats at 28 days. The data suggested that functional outcome is effectively improved by motor skill training rather than by simple exercises, and this may be related, at least partially, to uniquely lateralized synaptogenesis in the thalamus. Both Rota-rod and treadmill could be quantitatively used in rats for motor training of different complexity. PMID:12500709

  8. Taste intensity modulates effective connectivity from the insular cortex to the thalamus in humans.

    Science.gov (United States)

    Yeung, Andy Wai Kan; Tanabe, Hiroki C; Suen, Justin Long Kiu; Goto, Tazuko K

    2016-07-15

    Evaluation of taste intensity is one of the most important perceptual abilities in our daily life. In contrast with extensive research findings regarding the spatial representation of taste in the insula and thalamus, little is known about how the thalamus and insula communicate and reciprocally influence their activities for processing taste intensity. To examine this neurophysiological relationship, we investigated the modulatory effect of intensity of saltiness on connections in the network processing taste signals in the human brain. These "effective connectivity" relationships refer to the neurophysiological influence (including direction and strength of influence) of one brain region on another. Healthy adults (N=34), including 17 males and 17 females (mean age=21.3years, SD=2.4; mean body mass index (BMI)=20.2kg/m(2), SD=2.1) underwent functional magnetic resonance imaging as they tasted three concentrations of sodium chloride solutions. By effective connectivity analysis with dynamic causal modeling, we show that taste intensity enhances top-down signal transmission from the insular cortex to the thalamus. These results are the first to demonstrate the modulatory effect of taste intensity on the taste network in the human brain. PMID:27132544

  9. The evolution of the dorsal thalamus of jawed vertebrates, including mammals: cladistic analysis and a new hypothesis.

    Science.gov (United States)

    Butler, A B

    1994-01-01

    The evolution of the dorsal thalamus in various vertebrate lineages of jawed vertebrates has been an enigma, partly due to two prevalent misconceptions: the belief that the multitude of nuclei in the dorsal thalamus of mammals could be meaningfully compared neither with the relatively few nuclei in the dorsal thalamus of anamniotes nor with the intermediate number of dorsal thalamic nuclei of other amniotes and a definition of the dorsal thalamus that too narrowly focused on the features of the dorsal thalamus of mammals. The cladistic analysis carried out here allows us to recognize which features are plesiomorphic and which apomorphic for the dorsal thalamus of jawed vertebrates and to then reconstruct the major changes that have occurred in the dorsal thalamus over evolution. Embryological data examined in the context of Von Baerian theory (embryos of later-descendant species resemble the embryos of earlier-descendant species to the point of their divergence) supports a new 'Dual Elaboration Hypothesis' of dorsal thalamic evolution generated from this cladistic analysis. From the morphotype for an early stage in the embryological development of the dorsal thalamus of jawed vertebrates, the divergent, sequential stages of the development of the dorsal thalamus are derived for each major radiation and compared. The new hypothesis holds that the dorsal thalamus comprises two basic divisions--the collothalamus and the lemnothalamus--that receive their predominant input from the midbrain roof and (plesiomorphically) from lemniscal pathways, including the optic tract, respectively. Where present, the collothalamic, midbrain-sensory relay nuclei are homologous to each other in all vertebrate radiations as discrete nuclei. Within the lemnothalamus, the dorsal lateral geniculate nucleus of mammals and the dorsal lateral optic nucleus of non-synapsid amniotes (diapsid reptiles, birds and turtles) are homologous as discrete nuclei; most or all of the ventral nuclear group

  10. TGF-β1 induces an age-dependent inflammation of nerve ganglia and fibroplasia in the prostate gland stroma of a novel transgenic mouse.

    Directory of Open Access Journals (Sweden)

    David A Barron

    Full Text Available TGF-β1 is overexpressed in wound repair and in most proliferative disorders including benign prostatic hyperplasia and prostate cancer. The stromal microenvironment at these sites is reactive and typified by altered phenotype, matrix deposition, inflammatory responses, and alterations in nerve density and biology. TGF-β1 is known to modulate several stromal responses; however there are few transgenic models to study its integrated biology. To address the actions of TGF-β1 in prostate disorders, we targeted expression of an epitope tagged and constitutively active TGF-β1 via the enhanced probasin promoter to the murine prostate gland epithelium. Transgenic mice developed age-dependent lesions leading to severe, yet focal attenuation of epithelium, and a discontinuous basal lamina. These changes were associated with elevated fibroplasia and frequency of collagenous micronodules in collapsed acini, along with an induced inflammation in nerve ganglia and small vessels. Elevated recruitment of CD115+ myeloid cells but not mature macrophages was observed in nerve ganglia, also in an age-dependent manner. Similar phenotypic changes were observed using a human prostate epithelium tissue recombination xenograft model, where epithelial cells engineered to overexpress TGF-β1 induced fibrosis and altered matrix deposition concurrent with inflammation in the stromal compartment. Together, these data suggest that elevated TGF-β1 expression induces a fibroplasia stromal response associated with breach of epithelial wall structure and inflammatory involvement of nerve ganglia and vessels. The novel findings of ganglia and vessel inflammation associated with formation of collagenous micronodules in collapsed acini is important as each of these are observed in human prostate carcinoma and may play a role in disease progression.

  11. Karsinoma Sel Basal Pada Wajah

    OpenAIRE

    Hastuti

    2008-01-01

    Karsinoma sel basal merupakan tumor ganas pada lapisan epidermis kulit yang paling umum dijumpai. Lokasi tumor iui paling banyak pada wajah dibandingkan anggota tubuh lainnya. Etiologi tumor iui diduga berhubungan dengan cahaya matahari yang mengandung sinar ultraviolet yang karsinogenik. Klasifikasi tumor ini dibagi berdasarkan gambaran kliuis dan histopatologisnya. Diagnosa tumor ini dapat ditegakkan dengan pemeriksaan k1inis dan histologis, pemeriksaan radiologis jarang digunakan. Diag...

  12. Basal body structure in Trichonympha.

    Science.gov (United States)

    Guichard, Paul; Gönczy, Pierre

    2016-01-01

    Trichonympha is a symbiotic flagellate of many species of termites and of the wood-feeding cockroach. Remarkably, this unicellular organism harbors up to over ten thousand flagella on its surface, which serve to propel it through the viscous environment of the host hindgut. In the 1960s, analysis of resin-embedded Trichonympha samples by electron microscopy revealed that the basal bodies that give rise to these flagella are exceptionally long, with a proximal, cartwheel-bearing, region some 50 times longer than that of regular centrioles. In recent years, this salient feature has prompted the analysis of the 3D architecture of Trichonympha basal bodies in the native state using cryo-electron tomography. The resulting ~40 Å resolution map of the basal body proximal region revealed a number of novel features that may be conserved in centrioles of other systems. These include proximal-distal polarity of the pinhead structure that links the cartwheel to centriolar microtubules, as well as of the linker between the A and the C microtubules. Moreover, this work demonstrated that the cartwheel is made of stacked ring-like structures that likely each comprise 18 molecules of SAS-6 proteins. PMID:26937279

  13. Expression of serotonin receptor genes in cranial ganglia.

    Science.gov (United States)

    Maeda, Naohiro; Ohmoto, Makoto; Yamamoto, Kurumi; Kurokawa, Azusa; Narukawa, Masataka; Ishimaru, Yoshiro; Misaka, Takumi; Matsumoto, Ichiro; Abe, Keiko

    2016-03-23

    Taste cells release neurotransmitters to gustatory neurons to transmit chemical information they received. Sweet, umami, and bitter taste cells use ATP as a neurotransmitter. However, ATP release from sour taste cells has not been observed so far. Instead, they release serotonin when they are activated by sour/acid stimuli. Thus it is still controversial whether sour taste cells use ATP, serotonin, or both. By reverse transcription-polymerase chain reaction and subsequent in situ hybridization (ISH) analyses, we revealed that of 14 serotonin receptor genes only 5-HT3A and 5-HT3B showed significant/clear signals in a subset of neurons of cranial sensory ganglia in which gustatory neurons reside. Double-fluorescent labeling analyses of ISH for serotonin receptor genes with wheat germ agglutinin (WGA) in cranial sensory ganglia of pkd1l3-WGA mice whose sour neural pathway is visualized by the distribution of WGA originating from sour taste cells in the posterior region of the tongue revealed that WGA-positive cranial sensory neurons rarely express either of serotonin receptor gene. These results suggest that serotonin receptors expressed in cranial sensory neurons do not play any role as neurotransmitter receptor from sour taste cells. PMID:26854841

  14. Transition between Functional Regimes in an Integrate-And-Fire Network Model of the Thalamus

    Science.gov (United States)

    Barardi, Alessandro; Mazzoni, Alberto

    2016-01-01

    The thalamus is a key brain element in the processing of sensory information. During the sleep and awake states, this brain area is characterized by the presence of two distinct dynamical regimes: in the sleep state activity is dominated by spindle oscillations (7 − 15 Hz) weakly affected by external stimuli, while in the awake state the activity is primarily driven by external stimuli. Here we develop a simple and computationally efficient model of the thalamus that exhibits two dynamical regimes with different information-processing capabilities, and study the transition between them. The network model includes glutamatergic thalamocortical (TC) relay neurons and GABAergic reticular (RE) neurons described by adaptive integrate-and-fire models in which spikes are induced by either depolarization or hyperpolarization rebound. We found a range of connectivity conditions under which the thalamic network composed by these neurons displays the two aforementioned dynamical regimes. Our results show that TC-RE loops generate spindle-like oscillations and that a minimum level of clustering (i.e. local connectivity density) in the RE-RE connections is necessary for the coexistence of the two regimes. We also observe that the transition between the two regimes occurs when the external excitatory input on TC neurons (mimicking sensory stimulation) is large enough to cause a significant fraction of them to switch from hyperpolarization-rebound-driven firing to depolarization-driven firing. Overall, our model gives a novel and clear description of the role that the two types of neurons and their connectivity play in the dynamical regimes observed in the thalamus, and in the transition between them. These results pave the way for the development of efficient models of the transmission of sensory information from periphery to cortex. PMID:27598260

  15. The thalamus in cirrhotic patients with and without hepatic encephalopathy: A volumetric MRI study

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Ran, E-mail: taoran1648@yahoo.cn [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Department of Radiology, Bethune International Peace Hospital of People' s Liberty Army, Shijiazhuang 050082, Hebei Province (China); Zhang, Jiuquan, E-mail: jiuquanzhang@yahoo.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); You, Zhonglan, E-mail: you_zhonglan@163.com [Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Wei, Luqing, E-mail: weiluqing@foxmail.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Fan, Yi, E-mail: fanyi1978@yahoo.cn [Department of Infectious Diseases, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China); Cui, Jinguo, E-mail: cuijinguo2005@163.com [Department of Radiology, Bethune International Peace Hospital of People' s Liberty Army, Shijiazhuang 050082, Hebei Province (China); Wang, Jian, E-mail: wangjian_811@yahoo.com [Department of Radiology, Southwest Hospital, Third Military Medical University, Chongqing 400038 (China)

    2013-11-01

    Background and aims: The thalamus is a major relay and filter station in the central neural system. Some previous studies have suggested that the thalamus maybe implicated in the pathogenesis of hepatic encephalopathy. The aim of our study was to investigate changing thalamic volumes in cirrhotic patients with and without hepatic encephalopathy. Methods: Neuropsychological tests and structural MR scanning were performed on 24 cirrhotic patients, 23 cirrhotic patients with minimal hepatic encephalopathy, 24 cirrhotic patients during their first episode of overt hepatic encephalopathy, and 33 healthy controls. Voxel-based morphometry analysis was performed to detect gray matter morphological changes. The thalamus and whole brain volume were extrapolated. A receiver operating characteristic curve analysis of thalamic volumes was used to discriminate patients with minimal hepatic encephalopathy from those with hepatic cirrhosis. Results: Thalamic volume increased in a stepwise manner in patients with progressively worse stages of hepatic encephalopathy compared to healthy subjects. Additionally, a comparison of gray matter morphometry between patients with Child–Pugh grades A, B, or C and controls revealed a progression in thalamic volumes in parallel with the degree of liver failure. Moreover, thalamic volume was significantly correlated with the number connection test A time and digit-symbol test score in cirrhotic patients with minimal hepatic encephalopathy (r = 0.659, P = 0.001; r = −0.577, P = 0.004; respectively). The area under the receiver operating characteristic curve was 0.827 (P = 0.001). Conclusions: A significantly increased thalamic volume may be provide an objective imaging measure for predicting seizures due to minimal hepatic encephalopathy in cirrhotic patients.

  16. The involvement of the thalamus in semantic retrieval: a clinical group study.

    Science.gov (United States)

    Pergola, Giulio; Bellebaum, Christian; Gehlhaar, Britta; Koch, Benno; Schwarz, Michael; Daum, Irene; Suchan, Boris

    2013-06-01

    There is increasing attention about the role of the thalamus in high cognitive functions, including memory. Although the bulk of the evidence refers to episodic memory, it was recently proposed that the mediodorsal (MD) and the centromedian-parafascicular (CM-Pf) nuclei of the thalamus may process general operations supporting memory performance, not only episodic memory. This perspective agrees with other recent fMRI findings on semantic retrieval in healthy participants. It can therefore be hypothesized that lesions to the MD and the CM-Pf impair semantic retrieval. In this study, 10 patients with focal ischemic lesions in the medial thalamus and 10 healthy controls matched for age, education, and verbal IQ performed a verbal semantic retrieval task. Patients were assigned to a target clinical group and a control clinical group based on lesion localization. Patients did not suffer from aphasia and performed in the range of controls in a categorization and a semantic association task. However, target patients performed poorer than healthy controls on semantic retrieval. The deficit was not because of higher distractibility but of an increased rate of false recall and, in some patients, of a considerably increased rate of misses. The latter deficit yielded a striking difference between the target and the control clinical groups and is consistent with anomia. Follow-up high-resolution structural scanning session in a subsample of patients revealed that lesions in the CM-Pf and MD were primarily associated with semantic retrieval deficits. We conclude that integrity of the MD and the CM-Pf is required for semantic retrieval, possibly because of their role in the activation of phonological representations.

  17. Transition between Functional Regimes in an Integrate-And-Fire Network Model of the Thalamus.

    Science.gov (United States)

    Barardi, Alessandro; Garcia-Ojalvo, Jordi; Mazzoni, Alberto

    2016-01-01

    The thalamus is a key brain element in the processing of sensory information. During the sleep and awake states, this brain area is characterized by the presence of two distinct dynamical regimes: in the sleep state activity is dominated by spindle oscillations (7 - 15 Hz) weakly affected by external stimuli, while in the awake state the activity is primarily driven by external stimuli. Here we develop a simple and computationally efficient model of the thalamus that exhibits two dynamical regimes with different information-processing capabilities, and study the transition between them. The network model includes glutamatergic thalamocortical (TC) relay neurons and GABAergic reticular (RE) neurons described by adaptive integrate-and-fire models in which spikes are induced by either depolarization or hyperpolarization rebound. We found a range of connectivity conditions under which the thalamic network composed by these neurons displays the two aforementioned dynamical regimes. Our results show that TC-RE loops generate spindle-like oscillations and that a minimum level of clustering (i.e. local connectivity density) in the RE-RE connections is necessary for the coexistence of the two regimes. We also observe that the transition between the two regimes occurs when the external excitatory input on TC neurons (mimicking sensory stimulation) is large enough to cause a significant fraction of them to switch from hyperpolarization-rebound-driven firing to depolarization-driven firing. Overall, our model gives a novel and clear description of the role that the two types of neurons and their connectivity play in the dynamical regimes observed in the thalamus, and in the transition between them. These results pave the way for the development of efficient models of the transmission of sensory information from periphery to cortex. PMID:27598260

  18. MeCP2 Is Required for Normal Development of GABAergic Circuits in the Thalamus

    OpenAIRE

    Zhang, Zhong-wei; Zak, Joseph D.; Liu, Hong

    2010-01-01

    Methyl-CpG binding protein 2 (MeCP2) is highly expressed in neurons in the vertebrate brain, and mutations of the gene encoding MeCP2 cause the neurodevelopmental disorder Rett syndrome. This study examines the role of MeCP2 in the development and function of thalamic GABAergic circuits. Whole cell recordings were carried out in excitatory neurons of the ventrobasal complex (VB) of the thalamus and in inhibitory neurons of the reticular thalamic nucleus (RTN) in acute brain slices from mice a...

  19. Basal cell carcinoma of penis: case report.

    OpenAIRE

    Sulaiman, M Z; Polacarz, S V; Partington, P E

    1988-01-01

    Basal cell carcinoma of the penis is rare. A patient who presented with a penile and scrotal ulcer due to basal cell carcinoma is reported. Wide local excision and split skin grafting were performed to excise the lesion completely.

  20. The basal bodies of Chlamydomonas reinhardtii

    OpenAIRE

    Dutcher, Susan K.; O’Toole, Eileen T.

    2016-01-01

    The unicellular green alga, Chlamydomonas reinhardtii, is a biflagellated cell that can swim or glide. C. reinhardtii cells are amenable to genetic, biochemical, proteomic, and microscopic analysis of its basal bodies. The basal bodies contain triplet microtubules and a well-ordered transition zone. Both the mother and daughter basal bodies assemble flagella. Many of the proteins found in other basal body-containing organisms are present in the Chlamydomonas genome, and mutants in these genes...

  1. Pulmonary Metastasis of Basal Cell Carcinoma

    OpenAIRE

    Seo, Sang-Hee; Shim, Woo-Haing; SHIN, DONG-HOON; Kim, Yun-Seong; Sung, Hyun-Woo

    2011-01-01

    Although basal cell carcinoma is the most common skin cancer, it rarely metastasizes. Metastatic basal cell carcinoma may, therefore, initially elude diagnosis and management. We describe the case of a patient with a metastatic basal cell carcinoma present in the lungs. The differential diagnosis of suspected metastatic lesions should include metastases from a cutaneous basal cell carcinoma, in addition to those from more commonly metastasizing carcinomas, especially in patients with a histor...

  2. Basal cell carcinoma-treatment with cryosurgery

    Directory of Open Access Journals (Sweden)

    Kaur S

    2003-03-01

    Full Text Available Basal cell carcinoma is a common cutaneous malignancy, frequently occurring over the face in elderly individuals. Various therapeutic modalities are available to treat these tumors. We describe three patients with basal cell carcinoma successfully treated with cryosurgery and discuss the indications and the use of this treatment modality for basal cell carcinomas.

  3. Basal cell carcinoma-treatment with cryosurgery

    OpenAIRE

    Kaur S; Thami G; Kanwar A

    2003-01-01

    Basal cell carcinoma is a common cutaneous malignancy, frequently occurring over the face in elderly individuals. Various therapeutic modalities are available to treat these tumors. We describe three patients with basal cell carcinoma successfully treated with cryosurgery and discuss the indications and the use of this treatment modality for basal cell carcinomas.

  4. Spike-Timing Dependent Plasticity in the Striatum

    OpenAIRE

    Fino, Elodie; Venance, Laurent

    2010-01-01

    The striatum is the major input nucleus of basal ganglia, an ensemble of interconnected sub-cortical nuclei associated with fundamental processes of action-selection and procedural learning and memory. The striatum receives afferents from the cerebral cortex and the thalamus. In turn, it relays the integrated information towards the basal ganglia output nuclei through which it operates a selected activation of behavioral effectors. The striatal output neurons, the GABAergic medium-sized spiny...

  5. Spike-timing dependent plasticity in the striatum

    OpenAIRE

    Elodie Fino; Laurent Venance

    2010-01-01

    The striatum is the major input nucleus of basal ganglia, an ensemble of interconnected sub-cortical nuclei associated with fundamental processes of action-selection and procedural learning and memory. The striatum receives afferents from the cerebral cortex and the thalamus. In turn, it relays the integrated information towards the basal ganglia output nuclei through which it operates a selected activation of behavioral effectors. The striatal output neurons, the GABAergic medium-sized spiny...

  6. Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy.

    Science.gov (United States)

    Neubauer, Florian B; Sederberg, Audrey; MacLean, Jason N

    2014-01-01

    During the generalization of epileptic seizures, pathological activity in one brain area recruits distant brain structures into joint synchronous discharges. However, it remains unknown whether specific changes in local circuit activity are related to the aberrant recruitment of anatomically distant structures into epileptiform discharges. Further, it is not known whether aberrant areas recruit or entrain healthy ones into pathological activity. Here we study the dynamics of local circuit activity during the spread of epileptiform discharges in the zero-magnesium in vitro model of epilepsy. We employ high-speed multi-photon imaging in combination with dual whole-cell recordings in acute thalamocortical (TC) slices of the juvenile mouse to characterize the generalization of epileptic activity between neocortex and thalamus. We find that, although both structures are exposed to zero-magnesium, the initial onset of focal epileptiform discharge occurs in cortex. This suggests that local recurrent connectivity that is particularly prevalent in cortex is important for the initiation of seizure activity. Subsequent recruitment of thalamus into joint, generalized discharges is coincident with an increase in the coherence of local cortical circuit activity that itself does not depend on thalamus. Finally, the intensity of population discharges is positively correlated between both brain areas. This suggests that during and after seizure generalization not only the timing but also the amplitude of epileptiform discharges in thalamus is entrained by cortex. Together these results suggest a central role of neocortical activity for the onset and the structure of pathological recruitment of thalamus into joint synchronous epileptiform discharges.

  7. Parallel driving and modulatory pathways link the prefrontal cortex and thalamus.

    Directory of Open Access Journals (Sweden)

    Basilis Zikopoulos

    Full Text Available Pathways linking the thalamus and cortex mediate our daily shifts from states of attention to quiet rest, or sleep, yet little is known about their architecture in high-order neural systems associated with cognition, emotion and action. We provide novel evidence for neurochemical and synaptic specificity of two complementary circuits linking one such system, the prefrontal cortex with the ventral anterior thalamic nucleus in primates. One circuit originated from the neurochemical group of parvalbumin-positive thalamic neurons and projected focally through large terminals to the middle cortical layers, resembling 'drivers' in sensory pathways. Parvalbumin thalamic neurons, in turn, were innervated by small 'modulatory' type cortical terminals, forming asymmetric (presumed excitatory synapses at thalamic sites enriched with the specialized metabotropic glutamate receptors. A second circuit had a complementary organization: it originated from the neurochemical group of calbindin-positive thalamic neurons and terminated through small 'modulatory' terminals over long distances in the superficial prefrontal layers. Calbindin thalamic neurons, in turn, were innervated by prefrontal axons through small and large terminals that formed asymmetric synapses preferentially at sites with ionotropic glutamate receptors, consistent with a driving pathway. The largely parallel thalamo-cortical pathways terminated among distinct and laminar-specific neurochemical classes of inhibitory neurons that differ markedly in inhibitory control. The balance of activation of these parallel circuits that link a high-order association cortex with the thalamus may allow shifts to different states of consciousness, in processes that are disrupted in psychiatric diseases.

  8. Behavioral and cognitive changes after early postnatal lesions of the rat mediodorsal thalamus.

    Science.gov (United States)

    Ouhaz, Zakaria; Ba-M'hamed, Saadia; Mitchell, Anna S; Elidrissi, Abdeslem; Bennis, Mohamed

    2015-10-01

    Early insults to the thalamus result in functional and/or structural abnormalities in the cerebral cortex. However, differences in behavioral and cognitive changes after early insult are not well characterized. The present study assessed whether early postnatal damage to mediodorsal nucleus of the thalamus (MD), reciprocally interconnected with the prefrontal cortex, causes behavioral and cognitive alterations in young adult rats. Rat pups at postnatal day 4 received bilateral electrolytic lesion of MD, or a MD Sham lesion or were anesthetized controls; on recovery they were returned to their mothers until weaning. Seven weeks later, all rats were tested with the following behavioral and cognitive paradigms: T-maze test, open field test, actimetry, elevated plus maze test, social interactions test and passive avoidance test. Rats with bilateral MD damage presented with disrupted recognition memory, deficits in shifting response rules, significant hypoactivity, increased anxiety-like behavior, deficits in learning associations as well as decreased locomotor activity, and reduced social interactions compared to MD Sham lesion and anesthetized Control rats. The lesion also caused significant decreases in pyramidal cell density in three frontal cortex regions: medial infralimbic cortex, dorsolateral anterior cortex, and cingulate Cg1 cortex. The present findings suggest a functional role for MD in the postnatal maturation of affective behavior. Further some of the behavioral and cognitive alterations observed in these young adult rats after early MD lesion are reminiscent of those present in major psycho-affective disorders, such as schizophrenia in humans.

  9. The role of the anterior, mediodorsal, and parafascicular thalamus in instrumental conditioning

    Directory of Open Access Journals (Sweden)

    Laura Anne Bradfield

    2013-10-01

    Full Text Available The traditional animal model of instrumental behaviour has focused almost exclusively on structures within the cortico-striatal network and ignored the contributions of various thalamic nuclei despite large and specific connections with each of these structures. One possible reason for this is that the thalamus has been conventionally viewed as a mediator of general processes, such as attention, arousal and movement, that are not easily separated from more cognitive aspects of instrumental behaviour. Recent research has, however, begun to separate these roles. Here we review the role of three thalamic nuclei in instrumental conditioning: the anterior, the mediodorsal, and parafascicular thalamic nuclei. Early research suggested that anterior thalamic nuclei might regulate aspects of instrumental behaviour but, on review, we suggest that the types of tasks used in these studies were more likely to recruit Pavlovian processes. Indeed lesions of anterior thalamic nuclei have been found to have no effect on performance in instrumental free-operant tasks. By contrast the mediodorsal thalamus has been found to play a specific and important role in the acquisition of goal-directed action. We propose this role is related to its connections with prelimbic cortex and present new data that directly implicates this circuit in the acquisition of goal-directed actions. Finally we review evidence suggesting the parafascicular thalamic nucleus, although not critical for the acquisition or performance of instrumental actions, plays a specific role in regulating action flexibility.

  10. Effects of Shenpang acupoint-stimulation on estrogen receptor immunoreactive neurons in thalamus of rabbits

    Institute of Scientific and Technical Information of China (English)

    LUO Qihui; CHEN Zhengli; ZHU Chunmei; FAN Guangli; HUANG Yidan

    2007-01-01

    To investigate the effects of Shenpang acupoint-stimulation in reproductive endocrinology,the changes in estrogen receptor immunoreactive (ER-IR)neurons after Shenpang acupoint-stimulation were studied by using immnunohistochemistry.ER-IR positive reactions were detected in most nuclei of the thalamus.In the acupuncturetreated group,a great number of ER-IR positive neurons with clear dendrites existed in the nucleus,paraventricular nucleus,ventrolateral nucleus,ventromedial nucleus,ventroprincipal nucleus,centromedian nucleus,reticular nucleus,and periventricular nucleus of thalamus,and they were strongly stained.In addition,the ER-IR positive neurons were mainly located in the cytoplasm,nucleus and neutrite,and some also existed in the cytoplasmic membrane.In contrast,a few neurons existed in the above-mentioned nuclei in the control group,but they were slightly stained.It is concluded that Shenpang acupoint-stimulation can promote the expression of estrogen receptors in the above nuclei.

  11. Schwann cell cultures from human fetal dorsal root ganglia

    Institute of Scientific and Technical Information of China (English)

    Yaping Feng; Hui Zhu; Jiang Hao; Xinmin Wang; Shengping Wu; Li Bai; Xiangming Li; Yun Zha

    2009-01-01

    BACKGROUND:Previous studies have used many methods for in vitro Schwann cells (SCs) cul-tures and purification,such as single cell suspension and cytosine arabinoside.However,it has been difficult to obtain sufficient cellular density,and the procedures have been quite tedious.OBJECTIVE:To investigate the feasibility of culturing high-density SCs using fetal human dorsal root ganglion tissue explants.DESIGN,TIME AND SETTING:Cell culture and immunohistochemistry were performed at the Cen-tral Laboratory of Kunming General Hospital of Chinese PLA between March 2001 and October 2008.MATERIALS:Culture media containing 10% fetal bovine serum,as well as 0.2% collagenase and 0.25% trypsin were purchased from Gibco,USA;mouse anti-human S-100 monoclonal antibody and goat anti-mouse IgG labeled with horseradish peroxidase were provided by Beijing Institute of Bi-ological Products,China.METHODS:Primarily cultured SCs were dissociated from dorsal root ganglia of human aborted fe-tuses at 4-6 months pregnancy.Following removal of the dorsal root ganglion perineurium,the gan-glia were dissected into tiny pieces and digested with 0.2% collagenase and 0.25% trypsin (volume ratio 1:1),then explanted and cultured.SC purification was performed with 5 mL 10% fetal bovine serum added to the culture media,followed by differential adhesion.MAIN OUTCOME MEASURES:SCs morphology was observed under inverted phase contrast light microscopy.SC purity was evaluated according to percentage of S-100 immunostained cells.RESULTS:SCs were primarily cultured for 5-6 days and then subcultured for 4-5 passages.The highly enriched SC population reached > 95% purity and presented with normal morphology.CONCLUSION:A high purity of SCs was obtained with culture methods using human fetal dorsal root ganglion tissue explants.

  12. The basal bodies of Chlamydomonas reinhardtii.

    Science.gov (United States)

    Dutcher, Susan K; O'Toole, Eileen T

    2016-01-01

    The unicellular green alga, Chlamydomonas reinhardtii, is a biflagellated cell that can swim or glide. C. reinhardtii cells are amenable to genetic, biochemical, proteomic, and microscopic analysis of its basal bodies. The basal bodies contain triplet microtubules and a well-ordered transition zone. Both the mother and daughter basal bodies assemble flagella. Many of the proteins found in other basal body-containing organisms are present in the Chlamydomonas genome, and mutants in these genes affect the assembly of basal bodies. Electron microscopic analysis shows that basal body duplication is site-specific and this may be important for the proper duplication and spatial organization of these organelles. Chlamydomonas is an excellent model for the study of basal bodies as well as the transition zone. PMID:27252853

  13. Temporal and spatial dynamics of thalamus-evoked activity in the anterior cingulate cortex.

    Science.gov (United States)

    Chang, Wei-Chih; Lee, Chia-Ming; Shyu, Bai-Chuang

    2012-10-11

    In the present study, multielectrode array (MEA) recording was used to illustrate the spatial-temporal progression of anterior cingulate cortex (ACC) activity following stimulation of the thalamus in a thalamocingulate pathway-preserved slice. The MEA was placed under the slice that contained the ACC, and 60 channels of extracellular local field potentials evoked by bipolar electrical stimulation within the thalamus were analyzed. Several distinct thalamic-evoked responses were identified. The early negative component (N1; amplitude, -35.7 ± 5.9 μV) emerged in layer VI near the cingulum 8.4 ± 0.5 ms after stimulation. N1 progressed upward to layers V and II/III in a lateral-to-medial direction. Subsequently, a positive component (P; amplitude, 27.0 ± 3.2 μV) appeared 12.0 ± 0.6 ms after stimulation in layer VI. At 26.8 ± 1.1 ms, a second negative component (N2; amplitude, -20.9 ± 2.7 μV) became apparent in layers II/III and V, followed by a more ventrolateral component (N3; amplitude, -18.9 ± 2.9 μV) at 42.8 ± 2.6 ms. These two late components spread downward to layer VI in a medial-to-lateral direction. The trajectory paths of the evoked components were consistently represented with varied medial thalamic stimulation intensities and sites. Both AMPA/kainate and N-methyl-D-aspartate-type glutamate receptors involved in monosynaptic and polysynaptic transmission participated in this thalamocortical pathway. Morphine mainly diminished the two negative synaptic components, and this suppressive effect was reversed by naloxone. The present study confirmed that functional thalamocingulate activity was preserved in the brain-slice preparation. The thalamus-evoked responses were activated and progressed along a deep surface-deep trajectory loop across the ACC layers. Glutamatergic neurotransmitters were crucially involved in information processing. Opioid interneurons may play a modulatory role in regulating the signal flows in the cingulate cortex.

  14. Gene expression for peptides in neurons of the petrosal and nodose ganglia in rat.

    Science.gov (United States)

    Czyzyk-Krzeska, M F; Bayliss, D A; Seroogy, K B; Millhorn, D E

    1991-01-01

    In situ hybridization was used to determine whether genes for neuropeptides [substance P/neurokinin A (SP/NKA), calcitonin gene-related peptide (CGRP), somatostatin (SOM), neuropeptide tyrosine (NPY) and cholecystokinin (CCK)] are expressed in inferior ganglia of the vagus (nodose) and glossopharyngeal (petrosal) nerves. Synthetic oligodeoxyribonucleotides, complementary to the cognate, mRNAs were labeled with [32P] or [35S], and hybridized to 10 microns thick sections of unperfused tissue which were then processed for film and emulsion autoradiography. We found numerous, clustered neuronal perikarya throughout the nodose and petrosal ganglia that expressed preprotachykinin A (SP/NKA) and CGRP mRNAs to varying degrees. Neurons expressing preproSOM mRNA were less abundant and more scattered throughout both ganglia. Notably, we found mRNA for NPY in cells (usually 5-10 per section) in both ganglia. To our knowledge, this is first evidence for NPY in these sensory ganglia. In contrast to previous immunohistochemical findings, we found no evidence for expression of preproCCK in either the nodose or petrosal ganglia. The present findings demonstrate that cells of the nodose and petrosal ganglia express the genes for a number of neuropeptides that are presumably involved with transmission of visceral sensory afferent information to higher order neurons of the central nervous system. PMID:1708726

  15. Anterior thalamic nuclei lesions and recovery of function: Relevance to cognitive thalamus.

    Science.gov (United States)

    Dalrymple-Alford, John C; Harland, Bruce; Loukavenko, Elena A; Perry, Brook; Mercer, Stephanie; Collings, David A; Ulrich, Katharina; Abraham, Wickliffe C; McNaughton, Neil; Wolff, Mathieu

    2015-07-01

    Injury to the anterior thalamic nuclei (ATN) and their neural connections is the most consistent neuropathology associated with diencephalic amnesia. ATN lesions in rats produce memory impairments that support a key role for this region within an extended hippocampal system of complex overlapping neural connections. Environmental enrichment is a therapeutic tool that produces substantial, although incomplete, recovery of memory function after ATN lesions, even after the lesion-induced deficit has become established. Similarly, the neurotrophic agent cerebrolysin, also counters the negative effects of ATN lesions. ATN lesions substantially reduce c-Fos expression and spine density in the retrosplenial cortex, and reduce spine density on CA1 neurons; only the latter is reversed by enrichment. We discuss the implications of this evidence for the cognitive thalamus, with a proposal that there are genuine interactions among different but allied thalamo-cortical systems that go beyond a simple summation of their separate effects. PMID:25637779

  16. Semantic memory retrieval circuit: role of pre-SMA, caudate, and thalamus.

    Science.gov (United States)

    Hart, John; Maguire, Mandy J; Motes, Michael; Mudar, Raksha Anand; Chiang, Hsueh-Sheng; Womack, Kyle B; Kraut, Michael A

    2013-07-01

    We propose that pre-supplementary motor area (pre-SMA)-thalamic interactions govern processes fundamental to semantic retrieval of an integrated object memory. At the onset of semantic retrieval, pre-SMA initiates electrical interactions between multiple cortical regions associated with semantic memory subsystems encodings as indexed by an increase in theta-band EEG power. This starts between 100-150 ms after stimulus presentation and is sustained throughout the task. We posit that this activity represents initiation of the object memory search, which continues in searching for an object memory. When the correct memory is retrieved, there is a high beta-band EEG power increase, which reflects communication between pre-SMA and thalamus, designates the end of the search process and resultant in object retrieval from multiple semantic memory subsystems. This high beta signal is also detected in cortical regions. This circuit is modulated by the caudate nuclei to facilitate correct and suppress incorrect target memories.

  17. Functional Neurosurgery in the Human Thalamus by Transcranial Magnetic Resonance Guided Focused Ultrasound

    Science.gov (United States)

    Werner, Beat; Morel, Anne; Jeanmonod, Daniel; Martin, Ernst

    2009-04-01

    Potential applications of Transcranial Magnetic Resonance guided Focused Ultrasound (TcMRgFUS) include treatment of functional brain disorders, such as Parkinson's disease, dystonia and tremor, neurogenic pain and tinnitus, neuropsychiatric disorders and epilepsy. In this study we demonstrate the feasibility of non-invasive TcMRgFUS ablation of clinically well established targets in the human thalamus that are currently accessed stereotactically by interventional strategies based on the concept of the thalamocortical dysrhythmia (TCD). Thermal hotspots suitable for clinical intervention were created successfully in anatomical preparations of human ex-vivo heads under pseudo clinical conditions. The hotspots could be positioned at the target locations as needed and local energy deposition was sufficient to create tissue ablation. Numerical simulations based on these experimental data predict that the acoustic energy needed to create ablative lesions in-vivo will be within limits that can safely applied.

  18. Somatosensory brainstem, thalamus, and cortex of the California sea lion (Zalophus californianus).

    Science.gov (United States)

    Sawyer, Eva K; Turner, Emily C; Kaas, Jon H

    2016-06-15

    Pinnipeds (sea lions, seals, and walruses) are notable for many reasons, including their ape-sized brains, their adaptation to a coastal niche that combines mastery of the sea with strong ties to land, and the remarkable abilities of their trigeminal whisker system. However, little is known about the central nervous system of pinnipeds. Here we report on the somatosensory areas of the nervous system of the California sea lion (Zalophus californianus). Using stains for Nissl, cytochrome oxidase, and vesicular glutamate transporters, we investigated the primary somatosensory areas in the brainstem, thalamus, and cortex in one sea lion pup and the external anatomy of the brain in a second pup. We find that the sea lion's impressive array of whiskers is matched by a large trigeminal representation in the brainstem with well-defined parcellation that resembles the barrelettes found in rodents but scaled upward in size. The dorsal column nuclei are large and distinct. The ventral posterior nucleus of the thalamus has divisions, with a large area for the presumptive head representation. Primary somatosensory cortex is located in the neocortex just anterior to the main vertical fissure, and precisely locating it as we do here is useful for comparing the highly gyrified pinniped cortex with that of other carnivores. To our knowledge this work is the first comprehensive report on the central nervous system areas for any sensory system in a pinniped. The results may be useful both in the veterinary setting and for comparative studies related to brain evolution. J. Comp. Neurol. 524:1957-1975, 2016. © 2016 Wiley Periodicals, Inc. PMID:26878587

  19. Protein kinase C regulates tonic GABAA receptor-mediated inhibition in the hippocampus and thalamus

    Science.gov (United States)

    Bright, Damian P; Smart, Trevor G

    2013-01-01

    Tonic inhibition mediated by extrasynaptic GABAA receptors (GABAARs) is an important regulator of neuronal excitability. Phosphorylation by protein kinase C (PKC) provides a key mode of regulation for synaptic GABAARs underlying phasic inhibition; however, less attention has been focused on the plasticity of tonic inhibition and whether this can also be modulated by receptor phosphorylation. To address this issue, we used whole-cell patch clamp recording in acute murine brain slices at both room and physiological temperatures to examine the effects of PKC-mediated phosphorylation on tonic inhibition. Recordings from dentate gyrus granule cells in the hippocampus and dorsal lateral geniculate relay neurons in the thalamus demonstrated that PKC activation caused downregulation of tonic GABAAR-mediated inhibition. Conversely, inhibition of PKC resulted in an increase in tonic GABAAR activity. These findings were corroborated by experiments on human embryonic kidney 293 cells expressing recombinant α4β2δ GABAARs, which represent a key extrasynaptic GABAAR isoform in the hippocampus and thalamus. Using bath application of low GABA concentrations to mimic activation by ambient neurotransmitter, we demonstrated a similar inhibition of receptor function following PKC activation at physiological temperature. Live cell imaging revealed that this was correlated with a loss of cell surface GABAARs. The inhibitory effects of PKC activation on α4β2δ GABAAR activity appeared to be mediated by direct phosphorylation at a previously identified site on the β2 subunit, serine 410. These results indicate that PKC-mediated phosphorylation can be an important physiological regulator of tonic GABAAR-mediated inhibition. PMID:24102973

  20. Transformation of the neural code for tactile detection from thalamus to cortex.

    Science.gov (United States)

    Vázquez, Yuriria; Salinas, Emilio; Romo, Ranulfo

    2013-07-01

    To understand how sensory-driven neural activity gives rise to perception, it is essential to characterize how various relay stations in the brain encode stimulus presence. Neurons in the ventral posterior lateral (VPL) nucleus of the somatosensory thalamus and in primary somatosensory cortex (S1) respond to vibrotactile stimulation with relatively slow modulations (∼100 ms) of their firing rate. In addition, faster modulations (∼10 ms) time-locked to the stimulus waveform are observed in both areas, but their contribution to stimulus detection is unknown. Furthermore, it is unclear whether VPL and S1 neurons encode stimulus presence with similar accuracy and via the same response features. To address these questions, we recorded single neurons while trained monkeys judged the presence or absence of a vibrotactile stimulus of variable amplitude, and their activity was analyzed with a unique decoding method that is sensitive to the time scale of the firing rate fluctuations. We found that the maximum detection accuracy of single neurons is similar in VPL and S1. However, VPL relies more heavily on fast rate modulations than S1, and as a consequence, the neural code in S1 is more tolerant: its performance degrades less when the readout method or the time scale of integration is suboptimal. Therefore, S1 neurons implement a more robust code, one less sensitive to the temporal integration window used to infer stimulus presence downstream. The differences between VPL and S1 responses signaling the appearance of a stimulus suggest a transformation of the neural code from thalamus to cortex.

  1. BASAL CELL CARCINOMA WITH ECCRINE DIFFERENTIATION: A RARE ENTITY

    Directory of Open Access Journals (Sweden)

    Divvya

    2014-05-01

    Full Text Available Basal cell carcinoma preferentially occurs in the face where the surgical excision with adequate margin is curative. Sometimes basal cell carcinoma is also reported rarely in other sites especially associated with basal cell carcinoma syndrome. The histological variants are Nodular basal cell carcinoma, Keratotic basal cell carcinoma, Adenoid basal cell carcinoma, Basal cell carcinoma with sebaceous differentiation. Of these variants, Basal cell carcinoma with eccrine differentiation is practically very rare.

  2. BASAL CELL CARCINOMA WITH ECCRINE DIFFERENTIATION: A RARE ENTITY

    OpenAIRE

    Divvya; Rehana; Viswanathan; Krishnaswamy; Anvar Ali

    2014-01-01

    Basal cell carcinoma preferentially occurs in the face where the surgical excision with adequate margin is curative. Sometimes basal cell carcinoma is also reported rarely in other sites especially associated with basal cell carcinoma syndrome. The histological variants are Nodular basal cell carcinoma, Keratotic basal cell carcinoma, Adenoid basal cell carcinoma, Basal cell carcinoma with sebaceous differentiation. Of these variants, Basal cell carcinoma with eccrine differen...

  3. Neglected Giant Scalp Basal Cell Carcinoma

    OpenAIRE

    Anne Kristine Larsen, MD; Waseem-Asim Ghulam El-Charnoubi, MD; Julie Gehl, MD, PhD; Christen Krag, MD, PhD

    2014-01-01

    Summary: Rarely, basal cell carcinoma grows to a giant size, invading the underlying deep tissue and complicating the treatment and reconstruction modalities. A giant basal cell carcinoma on the scalp is in some cases treated with a combination of surgery and radiation therapy, resulting in local control, a satisfactory long-term cosmetic and functional result. We present a case with a neglected basal cell scalp carcinoma, treated with wide excision and postoperative radiotherapy, reconstruct...

  4. Metastatic Basal Cell Carcinoma Accompanying Gorlin Syndrome

    OpenAIRE

    Yeliz Bilir; Erkan Gokce; Banu Ozturk; Faik Alev Deresoy; Ruken Yuksekkaya; Emel Yaman

    2014-01-01

    Gorlin-Goltz syndrome or basal cell nevus syndrome is an autosomal dominant syndrome characterized by skeletal anomalies, numerous cysts observed in the jaw, and multiple basal cell carcinoma of the skin, which may be accompanied by falx cerebri calcification. Basal cell carcinoma is the most commonly skin tumor with slow clinical course and low metastatic potential. Its concomitance with Gorlin syndrome, resulting from a mutation in a tumor suppressor gene, may substantially change morbidity...

  5. Nogo-A is involved in secondary axonal degeneration of thalamus in hypertensive rats with focal cortical infarction.

    Science.gov (United States)

    Wang, Fang; Liang, Zhijian; Hou, Qinghua; Xing, Shihui; Ling, Li; He, Meixia; Pei, Zhong; Zeng, Jinsheng

    2007-05-01

    We investigate whether Nogo-A is involved in the secondary axonal degeneration in the thalamus after distal middle cerebral artery occlusion (MCAO) in stroke-prone renovascular hypertensive rats (RHRSP). The expression of Nogo-A in ipsilateral ventroposterior nucleus (VPN) of the thalamus in RHRSP was observed at 1, 2 and 4 weeks after distal MCAO. In addition, intracerebroventricular infusion of NEP1-40, a Nogo-66 receptor (NgR) antagonist peptide, was administered starting 24 h after MCAO and continued for 1, 2 and 4 weeks, respectively. Axonal damage and regeneration were evaluated by analysis of the immunoreactivity (IR) of amyloid betaA4 precursor protein (APP), growth associated protein 43 (GAP-43) and microtubule associated protein 2 (MAP-2) in ipsilateral VPN of the thalamus at 1, 2 and 4 weeks after distal MCAO. Following ischemia, the expression of Nogo-A in oligodendrocytes increased persistently and its localization became redistributed around damaged axons and dendrites. Administration of NEP1-40 downregulated the expression of Nogo-A, reduced axonal injury and enhanced axonal regeneration. Our data suggest that Nogo-A is involved in secondary axonal degeneration and that inhibition of Nogo-A can reduce neuronal damage in the thalamus after distal MCAO.

  6. Neuronal morphology and the synaptic organisation of sympathetic ganglia.

    Science.gov (United States)

    Gibbins, I L; Jobling, P; Messenger, J P; Teo, E H; Morris, J L

    2000-07-01

    In this article, we provide a short review of the structure and synaptic organisation of the final motor neurons in the sympathetic ganglia of mammals. Combinations of pathway tracing, multiple-labelling immunofluorescence and intracellular dye injection have shown that neurons in different functional pathways differ not only in their patterns of neuropeptide expression, but also in the size of their cell bodies and dendritic fields. Thus, vasoconstrictor neurons consistently are smaller than any other major functional class of neurons. Serial section ultrastructural analysis of dye filled neurons, together with electron microscopic and confocal microscopic analysis of immunolabelled synaptic inputs to sympathetic final motor neurons indicate that synapses are rare and randomly distributed over the surface of the neurons. The total number of synapses is simply proportional to the total surface area of the neurons. Many terminal boutons of peptide-containing preganglionic neurons do not make conventional synapses with target neurons. Furthermore, there is a spatial mismatch in the distribution of peptide-containing terminals and neurons expressing receptors for the corresponding peptides. Together, these results suggest that there are likely to be significant differences in the ways that the final sympathetic motor neurons in distinct functional pathways integrate their synaptic inputs. In at least some pathways, heterosynaptic actions of neuropeptides probably contribute to subtle modulation of ganglionic transmission.

  7. Varicella-zoster virus reactivation from multiple ganglia: a case report

    Directory of Open Access Journals (Sweden)

    Hashemilar Mazyar

    2009-09-01

    Full Text Available Abstract Introduction Simultaneous involvements of multiple cranial nerve ganglia (geniculate ganglion and peripheral ganglia of cranial nerves VIII, IX and X by varicella-zoster virus and its subsequent activation may result in the characteristic eruptions of herpes zoster cephalicus. Coexistence of facial palsy and involvement of upper cervical dermatomes by varicella-zoster virus is quite rare. Case presentation Here, we report a 71-year-old Iranian man with involvement of multiple sensory ganglia (geniculate ganglion and upper dorsal root ganglia by varicella-zoster virus. He presented with right-sided facial weakness along with vesicular eruptions on the right side of his neck, and second and third cervical dermatomes. Conclusion The present case is an example of herpes zoster cephalicus with cervical nerve involvement. Although resembling Ramsay Hunt syndrome with presence of facial nerve paralysis and accompanying vesicles, involvement of cervical dermatomes is not a feature of the classic Ramsay Hunt syndrome.

  8. The volumetric and shape changes of the putamen and thalamus in first episode, untreated major depressive disorder

    Directory of Open Access Journals (Sweden)

    Yi Lu

    2016-01-01

    Full Text Available Previous MRI studies confirmed abnormalities in the limbic-cortical-striatal-pallidal-thalamic (LCSPT network or limbic-cortico-striatal-thalamic-cortical (LCSTC circuits in patients with major depressive disorder (MDD, but few studies have investigated the subcortical structural abnormalities. Therefore, we sought to determine whether focal subcortical grey matter (GM changes might be present in MDD at an early stage. We recruited 30 first episode, untreated patients with major depressive disorder (MDD and 26 healthy control subjects. Voxel-based morphometry was used to evaluate cortical grey matter changes, and automated volumetric and shape analyses were used to assess volume and shape changes of the subcortical GM structures, respectively. In addition, probabilistic tractography methods were used to demonstrate the relationship between the subcortical and the cortical GM. Compared to healthy controls, MDD patients had significant volume reductions in the bilateral putamen and left thalamus (FWE-corrected, p < 0.05. Meanwhile, the vertex-based shape analysis showed regionally contracted areas on the dorsolateral and ventromedial aspects of the bilateral putamen, and on the dorsal and ventral aspects of left thalamus in MDD patients (FWE-corrected, p < 0.05. Additionally, a negative correlation was found between local atrophy in the dorsal aspects of the left thalamus and clinical variables representing severity. Furthermore, probabilistic tractography demonstrated that the area of shape deformation of the bilateral putamen and left thalamus have connections with the frontal and temporal lobes, which were found to be related to major depression. Our results suggested that structural abnormalities in the putamen and thalamus might be present in the early stages of MDD, which support the role of subcortical structure in the pathophysiology of MDD. Meanwhile, the present study showed that these subcortical structural abnormalities might be

  9. Local changes in neocortical circuit dynamics coincide with the spread of seizures to thalamus in a model of epilepsy

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    Florian B Neubauer

    2014-09-01

    Full Text Available During the generalization of epileptic seizures, pathological activity in one brain area recruits distant brain structures into joint synchronous discharges. However, it remains unknown whether specific changes in local circuit activity are related to the aberrant recruitment of anatomically distant structures into epileptiform discharges. Further, it is not known whether aberrant areas recruit or entrain healthy ones into pathological activity. Here we study the dynamics of local circuit activity during the spread of epileptiform discharges in the zero-magnesium in vitro model of epilepsy. We employ high-speed multi-photon imaging in combination with dual whole-cell recordings in acute thalamocortical slices of the juvenile mouse to characterize the generalization of epileptic activity between neocortex and thalamus. We find that, although both structures are exposed to zero-magnesium, the initial onset of focal epileptiform discharge occurs in cortex. This suggests that local recurrent connectivity that is particularly prevalent in cortex is important for the initiation of seizure activity. Subsequent recruitment of thalamus into joint, generalized discharges is coincident with an increase in the coherence of local cortical circuit activity that itself does not depend on thalamus. Finally, the intensity of population discharges is positively correlated between both brain areas. This suggests that during and after seizure generalization not only the timing but also the amplitude of epileptiform discharges in thalamus is entrained by cortex. Together these results suggest a central role of neocortical activity for the onset and the structure of pathological recruitment of thalamus into joint synchronous epileptiform discharges.

  10. Modulation of transmission in rat sympathetic ganglia by activation of presynaptic alpha- and beta-adrenoceptors.

    OpenAIRE

    Medgett, I.C.

    1983-01-01

    1 Conditions under which transmission in rat isolated superior cervical ganglia may be affected by activation of presynaptic alpha- and beta-adrenoceptors have been investigated by means of an extracellular recording method. 2 Clonidine caused a small hyperpolarization of the ganglia (mean EC50 approximately 2 nM) in unstimulated preparations; with continuous preganglionic stimulation at 0.2 Hz, clonidine markedly decreased the height of the compound action potential (mean EC50 approximately ...

  11. Readiness in the Basal Reader: An Update.

    Science.gov (United States)

    Perkins, Pamela

    A study examined two 1989 basal reading series' (published by McGraw Hill and Holt) readiness/priming sequences in order to ascertain the theoretical bases of each and then compared the findings with those of an earlier study. All pages of the readiness/priming sequence student texts and workbooks of both basal reading series were analyzed using…

  12. Early recognition of basal cell naevus syndrome

    NARCIS (Netherlands)

    Veenstra-Knol, HE; Scheewe, JH; van der Vlist, GJ; van Doorn, ME; Ausems, MGEM

    2005-01-01

    The basal cell naevus syndrome is an autosomal dominant syndrome characterised by major manifestations such as basal cell carcinomas, jaw cysts, palmar or plantar pits, and intracranial calcifications. Early recognition is important in order to reduce morbidity due to cutaneous and cerebral malignan

  13. Ganglia of the tarsal sinus: MR imaging features and clinical findings

    International Nuclear Information System (INIS)

    Purpose: To analyze MR imaging and clinical findings associated with ganglia of the tarsal sinus. Materials and methods: In a record search, ganglia of the tarsal sinus were retrospectively identified in 26 patients (mean age 48 ± 16 years), who underwent MR imaging for chronic ankle pain. Images were reviewed by two radiologists in consensus for size and location of ganglia, lesions of ligaments of the ankle and the tarsal sinus, tendon abnormalities, osteoarthritis, osseous erosions and bone marrow abnormalities. Medical records were reviewed for patient history and clinical findings. Results: Ganglia were associated with the interosseus ligament in 81%, the cervical ligament in 31% and the retinacula in 46% of cases. Signal alterations suggesting degeneration were found in 85%, 50% and 63% in case of the interosseus ligament, the cervical ligament and the retinacula, respectively. Scarring of the anterior talofibular ligament and the fibulocalcaneal ligament was found in 68% and 72% of the patients, respectively, while only 27% of the patients recalled ankle sprains. Ganglia at the retinacula were highly associated with synovitis and tendinosis of the posterior tibial tendon (p < 0.05). Conclusion: All patients with ganglia in the tarsal sinus presented with another pathology at the ankle, suggesting that degeneration of the tarsal sinus may be a secondary phenomenon, due to pathologic biomechanics at another site of the hind foot. Thus, in patients with degenerative changes of the tarsal sinus, one should be alerted and search for underlying pathology, which may be injury of the lateral collateral ligaments in up to 70%.

  14. The subdiaphragmatic part of the phrenic nerve - morphometry and connections to autonomic ganglia.

    Science.gov (United States)

    Loukas, Marios; Du Plessis, Maira; Louis, Robert G; Tubbs, R Shane; Wartmann, Christopher T; Apaydin, Nihal

    2016-01-01

    Few anatomical textbooks offer much information concerning the anatomy and distribution of the phrenic nerve inferior to the diaphragm. The aim of this study was to identify the subdiaphragmatic distribution of the phrenic nerve, the presence of phrenic ganglia, and possible connections to the celiac plexus. One hundred and thirty formalin-fixed adult cadavers were studied. The right phrenic nerve was found inferior to the diaphragm in 98% with 49.1% displaying a right phrenic ganglion. In 22.8% there was an additional smaller ganglion (right accessory phrenic ganglion). The remaining 50.9% had no grossly identifiable right phrenic ganglion. Most (65.5% of specimens) exhibited plexiform communications with the celiac ganglion, aorticorenal ganglion, and suprarenal gland. The left phrenic nerve inferior to the diaphragm was observed in 60% of specimens with 19% containing a left phrenic ganglion. No accessory left phrenic ganglia were observed. The left phrenic ganglion exhibited plexiform communications to several ganglia in 71.4% of specimens. Histologically, the right phrenic and left phrenic ganglia contained large soma concentrated in their peripheries. Both phrenic nerves and ganglia were closely related to the diaphragmatic crura. Surgically, sutures to approximate the crura for repair of hiatal hernias must be placed above the ganglia in order to avoid iatrogenic injuries to the autonomic supply to the diaphragm and abdomen. These findings could also provide a better understanding of the anatomy and distribution of the fibers of that autonomic supply.

  15. Single-unit analysis of the pallidum, thalamus and subthalamic nucleus in parkinsonian patients.

    Science.gov (United States)

    Magnin, M; Morel, A; Jeanmonod, D

    2000-01-01

    Microelectrode-guided stereotactic operations performed in 29 parkinsonian patients allowed the recording of 86 cells located in the globus pallidus and 563 in thalamic nuclei. In the globus pallidus, the average firing rate was significantly higher in the internal (91+/-52 Hz) than in the external (60+/-21 Hz) subdivision. This difference was further accentuated when the average firing rate in the external subdivision was compared with that of the internal part of the internal subdivision (114+/-30 Hz). A rhythmic modulation in globus pallidus activities was observed in 19.7% of the cells, and this only during rest tremor episodes. In these cases, modulation frequency of unit activities was not statistically different from the rest tremor frequency (average: 4.6+/-0.5 vs 4. 4+/-0.4 Hz, respectively). In the medial thalamus, four types of unit activities could be defined. A sporadic type was mainly found in the parvocellular division of the mediodorsal nucleus (96.8% of the cells recorded) and in the centre median-parafascicular complex (74.2%). Two other types of activities characterized by random or rhythmic bursts fulfilling the extracellular criteria of low-threshold calcium spike bursts were concentrated in the central lateral nucleus (62.3%) and the paralamellar division of the mediodorsal nucleus (34.1%). These activities could be recorded independently of the presence of a rest tremor. When a tremor episode occurred, the rhythmic low-threshold calcium spike bursts had an interburst frequency similar to rest tremor frequency, although they were not synchronized with it. The fourth type, the so-called tremor locked, was also characterized by rhythmic bursts which, however, did not display low-threshold calcium spike burst properties. These bursts occurred only when a rest tremor was present and was in-phase with the electromyographic bursts. All tremor-locked cells were located in the centre median-parafascicular complex. In the lateral thalamus, cells

  16. Functional Outcomes of Decompressive Craniectomy in Patients with Malignant Middle Cerebral Artery Infarction and Their Association with Preoperative Thalamus Deformation: An Analysis of 12 Patients.

    Science.gov (United States)

    Fukuoka, Takuya; Hayashi, Takeshi; Ohira, Masayuki; Kato, Yuji; Deguchi, Ichiro; Maruyama, Hajime; Abe, Tetsuya; Sano, Hiroyasu; Mizuno, Satoko; Nagamine, Yuito; Kurita, Hiroki; Takao, Masaki; Tanahashi, Norio

    2016-01-01

    Objective Decompressive craniectomy (DC) in patients with malignant middle cerebral artery (MCA) infarction is known to decrease the mortality rate. However, the functional outcomes (communication and oral intake) of this procedure remain unclear. Most patients with malignant MCA infarction exhibit a loss of consciousness, which may be principally governed by the thalamus. We herein investigated the functional outcomes of DC at 90 days after the onset of malignant MCA infarction and their association with preoperative thalamus deformation, which can occur due to pressure and edema. Methods Twelve of 2,692 patients with acute cerebral infarction were diagnosed with malignant MCA infarction and underwent DC. We evaluated preoperative thalamus damage using brain computed tomography and its association with communication and oral intake abilities and the modified Rankin Scale (mRS) and Barthel index scores at 90 days after stroke onset. Results The mRS score at 90 days was 0-4 in five patients. Seven patients could communicate immediately after surgery, while five could do so by 90 days. Five patients were able to resume the oral intake of food at 90 days. All patients with preoperative thalamus deformation showed a poor recovery, while those with absent or slight preoperative thalamus deformation showed a good recovery. Conclusion Patients with preoperative thalamus deformation caused by pressure and edema show a poor oral intake and communication abilities after DC, suggesting that preoperative thalamus deformation is a predictor of poor functional outcomes after DC in patients with malignant MCA infarction. PMID:27477404

  17. Metastatic Basal cell carcinoma accompanying gorlin syndrome.

    Science.gov (United States)

    Bilir, Yeliz; Gokce, Erkan; Ozturk, Banu; Deresoy, Faik Alev; Yuksekkaya, Ruken; Yaman, Emel

    2014-01-01

    Gorlin-Goltz syndrome or basal cell nevus syndrome is an autosomal dominant syndrome characterized by skeletal anomalies, numerous cysts observed in the jaw, and multiple basal cell carcinoma of the skin, which may be accompanied by falx cerebri calcification. Basal cell carcinoma is the most commonly skin tumor with slow clinical course and low metastatic potential. Its concomitance with Gorlin syndrome, resulting from a mutation in a tumor suppressor gene, may substantially change morbidity and mortality. A 66-year-old male patient with a history of recurrent basal cell carcinoma was presented with exophthalmus in the left eye and the lesions localized in the left lateral orbita and left zygomatic area. His physical examination revealed hearing loss, gapped teeth, highly arched palate, and frontal prominence. Left orbital mass, cystic masses at frontal and ethmoidal sinuses, and multiple pulmonary nodules were detected at CT scans. Basal cell carcinoma was diagnosed from biopsy of ethmoid sinus. Based on the clinical and typical radiological characteristics (falx cerebri calcification, bifid costa, and odontogenic cysts), the patient was diagnosed with metastatic skin basal cell carcinoma accompanied by Gorlin syndrome. Our case is a basal cell carcinoma with aggressive course accompanying a rarely seen syndrome.

  18. Transient inactivation of the posterior paraventricular nucleus of the thalamus blocks cocaine-seeking behavior.

    Science.gov (United States)

    Matzeu, A; Weiss, F; Martin-Fardon, R

    2015-11-01

    Originally studied for its role in energy homeostasis, the paraventricular nucleus of the thalamus (PVT) has recently gained attention because of its involvement in the modulation of drug-directed behavior. The posterior part of the PVT (pPVT) is connected with brain structures that modulate motivated behavior, and we tested whether the pPVT plays a pivotal role in cocaine seeking. The aim of the present study was to investigate whether transient inactivation of the pPVT prevents cue-induced reinstatement of cocaine seeking but not natural reward seeking. Male Wistar rats were trained to associate a discriminative stimulus (S(+)) with the availability of cocaine or a highly palatable conventional reinforcer, sweetened condensed milk (SCM). Following extinction, the cocaine S(+) and SCM S(+) elicited comparable levels of reinstatement. Intra-pPVT administration of the γ-aminobutyric acid-A (GABAA) and GABAB receptor agonists muscimol and baclofen (0.06 and 0.6mM, respectively) prior to the presentation of the cocaine or SCM S(+) completely prevented the reinstatement of cocaine seeking, with no statistically significant effects on SCM seeking. These data show that the pPVT plays an important role in neuronal mechanisms that drive cocaine-seeking behavior. PMID:26455867

  19. A role for midline and intralaminar thalamus in the associative blocking of Pavlovian fear conditioning.

    Science.gov (United States)

    Sengupta, Auntora; McNally, Gavan P

    2014-01-01

    Fear learning occurs in response to positive prediction error, when the expected outcome of a conditioning trial exceeds that predicted by the conditioned stimuli present. This role for error in Pavlovian association formation is best exemplified by the phenomenon of associative blocking, whereby prior fear conditioning of conditioned stimulus (CS) A is able to prevent learning to CSB when they are conditioned in compound. The midline and intralaminar thalamic nuclei (MIT) are well-placed to contribute to fear prediction error because they receive extensive projections from the midbrain periaqueductal gray-which has a key role in fear prediction error-and project extensively to prefrontal cortex and amygdala. Here we used an associative blocking design to study the role of MIT in fear learning. In Stage I rats were trained to fear CSA via pairings with shock. In Stage II rats received compound fear conditioning of CSAB paired with shock. On test, rats that received Stage I training expressed less fear to CSB relative to control rats that did not receive this training. Microinjection of bupivacaine into MIT prior to Stage II training had no effect on the expression of fear during Stage II and had no effect on fear learning in controls, but prevented associative blocking and so enabled fear learning to CSB. These results show an important role for MIT in predictive fear learning and are discussed with reference to previous findings implicating the midline and posterior intralaminar thalamus in fear learning and fear responding.

  20. A role for midline and intralaminar thalamus in the associative blocking of Pavlovian fear conditioning

    Directory of Open Access Journals (Sweden)

    Auntora eSengupta

    2014-05-01

    Full Text Available Fear learning occurs in response to positive prediction error, when the expected outcome of a conditioning trial exceeds that predicted by the conditioned stimuli present. This role for error in Pavlovian association formation is best exemplified by the phenomenon of associative blocking, whereby prior fear conditioning of conditioned stimulus (CS A is able to prevent learning to CSB when they are conditioned in compound. The midline and intralaminar thalamic nuclei (MIT are well placed to contribute to fear prediction error because they receive extensive projections from the midbrain periaqueductal gray – which has a key role in fear prediction error – and project extensively to prefrontal cortex and amygdala. Here we used an associative blocking design to study the role of MIT in fear learning. In Stage I rats were trained to fear CSA via pairings with shock. In Stage II rats received compound fear conditioning of CSAB paired with shock. On test, rats that received Stage I training expressed less fear to CSB relative to control rats that did not receive this training. Microinjection of bupivacaine into MIT prior to Stage II training had no effect on the expression of fear during Stage II and had no effect on fear learning in controls, but prevented associative blocking and so enabled fear learning to CSB. These results show an important role for MIT in predictive fear learning and are discussed with reference to previous findings implicating the midline and posterior intralaminar thalamus in fear learning and fear responding.

  1. Distribution of dopamine D2-like receptors in the human thalamus: autoradiographic and PET studies.

    Science.gov (United States)

    Rieck, Richard W; Ansari, M S; Whetsell, William O; Deutch, Ariel Y; Kessler, Robert M

    2004-02-01

    The distribution of dopamine (DA) D(2)-like receptors in the human thalamus was studied using in vitro autoradiographic techniques and in vivo positron emission tomography in normal control subjects. [(125)I]Epidepride, which binds with high affinity to DA D(2) and D(3) receptors, was used in autoradiographic studies to determine the distribution and density of D(2)-like receptors, and the epidepride analogue [(18)F]fallypride positron was used for positron emission tomography studies to delineate D(2)-like receptors in vivo. Both approaches revealed a heterogeneous distribution of thalamic D(2/3) receptors, with relatively high densities in the intralaminar and midline thalamic nuclei, including the paraventricular, parataenial, paracentral, centrolateral, and centromedian/parafascicular nuclei. Moderate densities of D(2/3) sites were seen in the mediodorsal and anterior nuclei, while other thalamic nuclei expressed lower levels of D(2)-like receptors. Most thalamic nuclei that express high densities of D(2)-like receptors project to forebrain DA terminal fields, suggesting that both the thalamic neurons expressing D(2)-like receptors and the projection targets of these neurons are regulated by DA. Because the midline/intralaminar nuclei receive prominent projections from both the ascending reticular activating core and the hypothalamus, these thalamic nuclei may integrate activity conveying both interoceptive and exteroceptive information to telencephalic DA systems involved in reward and cognition. PMID:14627996

  2. Clock face model applied to tibial intraneural ganglia in the popliteal fossa

    Energy Technology Data Exchange (ETDEWEB)

    Spinner, Robert J. [Mayo Clinic, Department of Neurologic Surgery, Rochester, MN (United States); Mayo Clinic, Department of Orthopedics, Rochester, MN (United States); Mayo Clinic, Rochester, MN (United States); Hebert-Blouin, Marie-Noelle [Mayo Clinic, Department of Neurologic Surgery, Rochester, MN (United States); Maniker, Allen H. [Beth Israel Hospital, Department of Neurosurgery, New York, NY (United States); Amrami, Kimberly K. [Mayo Clinic, Department of Neurologic Surgery, Rochester, MN (United States); Mayo Clinic, Department of Radiology, Rochester, MN (United States)

    2009-07-15

    Tibial intraneural ganglia occurring in the popliteal fossa are often misdiagnosed because of their relative rarity. Their joint connection is typically not recognized and therefore not treated, leading to recurrence. This is a retrospective clinical study. Magnetic resonance images (MRIs) of six patients with confirmed tibial intraneural ganglia arising from the superior tibiofibular joint were analyzed and were compared to ten individuals with normal tibial nerves who were imaged with MRI. All studies were interpreted as left-sided. A previously designed clock face model introduced for peroneal intraneural ganglia was used to describe the superior tibiofibular joint connection (tail sign). A single axial image was sought to determine the normal anatomic and pathologic relationships of the tibial nerve and tibial articular branch to the superior tibiofibular joint. In all patients with intraneural ganglia, a single conventional axial image at the mid-fibular head level could reliably demonstrate: (1) intraneural cyst within the articular branch at the superior tibiofibular joint connection (tail sign) between 8 and 9 o'clock and intraneural cyst within the tibial nerve, (2) the central location of the tibial nerve posterior to the tibia, and (3) popliteus muscle denervation changes and atrophy (popliteus sign). This technique can provide radiologists and surgeons with rapid and reproducible information for diagnosis and treatment planning of tibial intraneural ganglia. Similar to its use with the clock face model in peroneal intraneural ganglia, a standard axial image at the mid-fibular head level can be used to interpret key features of tibial intraneural ganglia and identify the joint connection. Improved identification of the presence of a joint connection will change the therapeutic approach of this pathology and reduce cyst recurrences. (orig.)

  3. Thermodynamic Significance of Human Basal Metabolism

    Institute of Scientific and Technical Information of China (English)

    WangCuncheng

    1993-01-01

    The human basal state,a non-equilibrium steady state,is analysed in this paper in the light of the First and Second Laws of Thermodynamics whereby the thermodynamic significance of the basal metabolic rate and its distinction to the dissipation function and exergy loss are identified.The analysis demonstrates the correct expression of the effects of the blood flow on the heat balance in a human-body bio-heat model and the relationship between the basal metabolic rate and the blood perfusion.

  4. Neglected giant scalp Basal cell carcinoma

    DEFF Research Database (Denmark)

    Larsen, Anne Kristine; El-Charnoubi, Waseem-Asim Ghulam; Gehl, Julie;

    2014-01-01

    SUMMARY: Rarely, basal cell carcinoma grows to a giant size, invading the underlying deep tissue and complicating the treatment and reconstruction modalities. A giant basal cell carcinoma on the scalp is in some cases treated with a combination of surgery and radiation therapy, resulting in local...... control, a satisfactory long-term cosmetic and functional result. We present a case with a neglected basal cell scalp carcinoma, treated with wide excision and postoperative radiotherapy, reconstructed with a free latissimus dorsi flap. The cosmetic result is acceptable and there is no sign of recurrence...

  5. Neglected Giant Scalp Basal Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Anne Kristine Larsen, MD

    2014-03-01

    Full Text Available Summary: Rarely, basal cell carcinoma grows to a giant size, invading the underlying deep tissue and complicating the treatment and reconstruction modalities. A giant basal cell carcinoma on the scalp is in some cases treated with a combination of surgery and radiation therapy, resulting in local control, a satisfactory long-term cosmetic and functional result. We present a case with a neglected basal cell scalp carcinoma, treated with wide excision and postoperative radiotherapy, reconstructed with a free latissimus dorsi flap. The cosmetic result is acceptable and there is no sign of recurrence 1 year postoperatively.

  6. Induction of c-Fos expression in the mammillary bodies, anterior thalamus and dorsal hippocampus after fear conditioning.

    Science.gov (United States)

    Conejo, Nélida M; González-Pardo, Héctor; López, Matías; Cantora, Raúl; Arias, Jorge L

    2007-09-14

    The aim of the present study was to provide further evidence on the role of particular subdivisions of the mammillary bodies, anterior thalamus and dorsal hippocampus to contextual and auditory fear conditioning. We used c-Fos expression as a marker of neuronal activation to compare rats that received tone-footshock pairings in a distinctive context (conditioned group) to rats being exposed to both the context and the auditory CS without receiving footshocks (unconditioned group), and naïve rats that were only handled. Fos immunoreactivity was significantly increased only in the anterodorsal thalamic nucleus and the lateral mammillary nucleus of the conditioned group. However, the dorsal hippocampus showed the highest density of c-Fos positive nuclei in the naïve group as compared to the other groups. Together, our data support previous studies indicating a particular involvement of the mammillary bodies and anterior thalamus in fear conditioning. PMID:17683804

  7. Heterogeneity in expression of functional ionotropic glutamate and GABA receptors in astrocytes across brain regions: insights from the thalamus

    OpenAIRE

    Höft, Simon; Griemsmann, Stephanie; Seifert, Gerald; Steinhäuser, Christian

    2014-01-01

    Astrocytes may express ionotropic glutamate and gamma-aminobutyric acid (GABA) receptors, which allow them to sense and to respond to neuronal activity. However, so far the properties of astrocytes have been studied only in a few brain regions. Here, we provide the first detailed receptor analysis of astrocytes in the murine ventrobasal thalamus and compare the properties with those in other regions. To improve voltage-clamp control and avoid indirect effects during drug applications, freshly...

  8. Connectivity-based parcellation of the thalamus explains specific cognitive and behavioural symptoms in patients with bilateral thalamic infarct.

    Directory of Open Access Journals (Sweden)

    Laura Serra

    Full Text Available A novel approach based on diffusion tractography was used here to characterise the cortico-thalamic connectivity in two patients, both presenting with an isolated bilateral infarct in the thalamus, but exhibiting partially different cognitive and behavioural profiles. Both patients (G.P. and R.F. had a pervasive deficit in episodic memory, but only one of them (R.F. suffered also from a dysexecutive syndrome. Both patients had an MRI scan at 3T, including a T1-weighted volume. Their lesions were manually segmented. T1-volumes were normalised to standard space, and the same transformations were applied to the lesion masks. Nineteen healthy controls underwent a diffusion-tensor imaging (DTI scan. Their DTI data were normalised to standard space and averaged. An atlas of Brodmann areas was used to parcellate the prefrontal cortex. Probabilistic tractography was used to assess the probability of connection between each voxel of the thalamus and a set of prefrontal areas. The resulting map of corticothalamic connections was superimposed onto the patients' lesion masks, to assess whether the location of the thalamic lesions in R.F. (but not in G. P. implied connections with prefrontal areas involved in dysexecutive syndromes. In G.P., the lesion fell within areas of the thalamus poorly connected with prefrontal areas, showing only a modest probability of connection with the anterior cingulate cortex (ACC. Conversely, R.F.'s lesion fell within thalamic areas extensively connected with the ACC bilaterally, with the right dorsolateral prefrontal cortex, and with the left supplementary motor area. Despite a similar, bilateral involvement of the thalamus, the use of connectivity-based segmentation clarified that R.F.'s lesions only were located within nuclei highly connected with the prefrontal cortical areas, thus explaining the patient's frontal syndrome. This study confirms that DTI tractography is a useful tool to examine in vivo the effect of focal

  9. Functional MRI activity in the thalamus and occipital cortex of anesthetized dogs induced by monocular and binocular stimulation.

    OpenAIRE

    Willis, C K; Quinn, R P; McDonell, W M; Gati, J; Partlow, G; Vilis, T.

    2001-01-01

    The neuroanatomy of the mammalian visual system has received considerable attention through electrophysiological study of cats and non-human primates, and through neuroimaging of humans. Canine neuroanatomy, however, has received much less attention, limiting our understanding of canine vision and visual pathways. As an early step in applying blood oxygenation level dependant (BOLD) functional magnetic resonance imaging (fMRI) for veterinary use, we compared visual activity in the thalamus an...

  10. Postnatal development of synaptic properties of the GABAergic projection from the inferior colliculus to the auditory thalamus

    OpenAIRE

    Venkataraman, Yamini; Bartlett, Edward L.

    2013-01-01

    The development of auditory temporal processing is important for processing complex sounds as well as for acquiring reading and language skills. Neuronal properties and sound processing change dramatically in auditory cortex neurons after the onset of hearing. However, the development of the auditory thalamus or medial geniculate body (MGB) has not been well studied over this critical time window. Since synaptic inhibition has been shown to be crucial for auditory temporal processing, this st...

  11. The associative and limbic thalamus in the pathophysiology of obsessive-compulsive disorder: an experimental study in the monkey.

    Science.gov (United States)

    Rotge, J Y; Aouizerate, B; Amestoy, V; Lambrecq, V; Langbour, N; Nguyen, T H; Dovero, S; Cardoit, L; Tignol, J; Bioulac, B; Burbaud, P; Guehl, D

    2012-01-01

    Obsessive-compulsive disorder (OCD) is a frequent psychiatric disorder characterized by repetitive intrusive thoughts and severe anxiety, leading to compulsive behaviors. Although medical treatment is effective in most cases, resistance is observed in about 30% of patients. In this context, deep brain stimulation (DBS) of the caudate or subthalamic nuclei has been recently proposed with encouraging results. However, some patients were unimproved or exhibited awkward side effects. Therefore, exploration of new targets for DBS remains critical in OCD. In the latter, functional imaging studies revealed overactivity in the limbic and associative cortico-subcortical loops encompassing the thalamus. However, the role of the thalamus in the genesis of repetitive behaviors and related anxiety is unknown. Here, we tested the hypothesis that pharmacological-induced overactivity of the medial thalamus could give rise to abnormal behaviors close to that observed in OCD. We modulated the ventral anterior (VA) and medial dorsal (MD) nuclei activity by in situ bicuculline (GABA(A) antagonist) microinjections in subhuman primates and assessed their pharmacological-induced behavior. Bicuculline injections within the VA caused significant repetitive and time-consuming motor acts whereas those performed within the MD induced symptoms of dysautonomic dysregulation along with abnormal vocalizations and marked motor hypoactivity. These findings suggest that overactivation of the VA and MD nuclei of the thalamus provokes compulsive-like behaviors and neurovegetative manifestations usually associated with the feeling of anxiety in OCD patients. In further research, this translational approach should allow us to test the effectiveness and side effects of these thalamic nuclei DBS in monkey and perhaps, in a second step, to propose a transfer of this technique to severely disabled OCD patients. PMID:23010765

  12. Apico-basal polarity complex and cancer

    Indian Academy of Sciences (India)

    Mohammed Khursheed; Murali Dharan Bashyam

    2014-03-01

    Apico-basal polarity is a cardinal molecular feature of adult eukaryotic epithelial cells and appears to be involved in several key cellular processes including polarized cell migration and maintenance of tissue architecture. Epithelial cell polarity is maintained by three well-conserved polarity complexes, namely, PAR, Crumbs and SCRIB. The location and interaction between the components of these complexes defines distinct structural domains of epithelial cells. Establishment and maintenance of apico-basal polarity is regulated through various conserved cell signalling pathways including TGF, Integrin and WNT signalling. Loss of cell polarity is a hallmark for carcinoma, and its underlying molecular mechanism is beginning to emerge from studies on model organisms and cancer cell lines. Moreover, deregulated expression of apico-basal polarity complex components has been reported in human tumours. In this review, we provide an overview of the apico-basal polarity complexes and their regulation, their role in cell migration, and finally their involvement in carcinogenesis.

  13. The many faces of basal cell carcinoma

    OpenAIRE

    Jackson, Robert

    1982-01-01

    Basal cell carcinoma is the most easily cured carcinoma, but because of the many forms it can take, and because it grows so slowly, it can be misdiagnosed or neglected. The author discusses its more common forms and etiologic considerations.

  14. Automatic basal slice detection for cardiac analysis

    Science.gov (United States)

    Paknezhad, Mahsa; Marchesseau, Stephanie; Brown, Michael S.

    2016-03-01

    Identification of the basal slice in cardiac imaging is a key step to measuring the ejection fraction (EF) of the left ventricle (LV). Despite research on cardiac segmentation, basal slice identification is routinely performed manually. Manual identification, however, has been shown to have high inter-observer variability, with a variation of the EF by up to 8%. Therefore, an automatic way of identifying the basal slice is still required. Prior published methods operate by automatically tracking the mitral valve points from the long-axis view of the LV. These approaches assumed that the basal slice is the first short-axis slice below the mitral valve. However, guidelines published in 2013 by the society for cardiovascular magnetic resonance indicate that the basal slice is the uppermost short-axis slice with more than 50% myocardium surrounding the blood cavity. Consequently, these existing methods are at times identifying the incorrect short-axis slice. Correct identification of the basal slice under these guidelines is challenging due to the poor image quality and blood movement during image acquisition. This paper proposes an automatic tool that focuses on the two-chamber slice to find the basal slice. To this end, an active shape model is trained to automatically segment the two-chamber view for 51 samples using the leave-one-out strategy. The basal slice was detected using temporal binary profiles created for each short-axis slice from the segmented two-chamber slice. From the 51 successfully tested samples, 92% and 84% of detection results were accurate at the end-systolic and the end-diastolic phases of the cardiac cycle, respectively.

  15. Cerebrolysin reduces amyloid-β deposits, apoptosis and autophagy in the thalamus and improves functional recovery after cortical infarction.

    Science.gov (United States)

    Xing, Shihui; Zhang, Jian; Dang, Chao; Liu, Gang; Zhang, Yusheng; Li, Jingjing; Fan, Yuhua; Pei, Zhong; Zeng, Jinsheng

    2014-02-15

    Focal cerebral infarction causes amyloid-β (Aβ) deposits and secondary thalamic neuronal degeneration. The present study aimed to determine the protective effects of Cerebrolysin on Aβ deposits and secondary neuronal damage in thalamus after cerebral infarction. At 24h after distal middle cerebral artery occlusion (MCAO), Cerebrolysin (5 ml/kg) or saline as control was once daily administered for consecutive 13 days by intraperitoneal injection. Sensory function and secondary thalamic damage were assessed with adhesive-removal test, Nissl staining and immunofluorescence at 14 days after MCAO. Aβ deposits, activity of β-site amyloid precursor protein-cleaving enzyme 1 (BACE1), apoptosis and autophagy were determined by TUNEL staining, immunofluorescence and immunoblot. The results showed that Cerebrolysin significantly improved sensory deficit compared to controls (pCerebrolysin, which was accompanied by decreases in neuronal loss and astroglial activation compared to controls (all p Cerebrolysin markedly inhibited cleaved caspase-3, conversion of LC3-II, downregulation of Bcl-2 and upregulation of Bax in the ipsilateral thalamus compared to controls (all pCerebrolysin reduces Aβ deposits, apoptosis and autophagy in the ipsilateral thalamus, which may be associated with amelioration of secondary thalamic damage and functional recovery after cerebral infarction. PMID:24315581

  16. Memory signals from the thalamus: early thalamocortical phase synchronization entrains gamma oscillations during long-term memory retrieval.

    Science.gov (United States)

    Staudigl, Tobias; Zaehle, Tino; Voges, Jürgen; Hanslmayr, Simon; Esslinger, Christine; Hinrichs, Hermann; Schmitt, Friedhelm C; Heinze, Hans-Jochen; Richardson-Klavehn, Alan

    2012-12-01

    The thalamus is believed to be a key node in human memory networks, however, very little is known about its real-time functional role. Here we examined the dynamics of thalamocortical communication during long-term episodic memory retrieval in two experiments. In experiment 1, intrathalamic and surface EEG was recorded in an epileptic patient implanted with depth electrodes for brain stimulation therapy. In a recognition memory test, early (300-500 ms) stimulus-linked oscillatory synchrony between mediodorsal thalamic and frontal surface electrodes at beta frequency (20 Hz) was enhanced for correctly remembered old compared to correctly rejected new items. Directionality measures (Granger causality) indicated that the thalamus was the sender, and the neocortex the receiver, of this beta signal, which also modulated the power of neocortical gamma (55-80 Hz) oscillations (cross-frequency coupling). Experiment 2 validated the cross-frequency coupling effects in a healthy participant sample. Confirming the findings from experiment 1, significantly increased cross-frequency coupling was found over frontal scalp electrodes during successful recognition. Extending anatomical knowledge on thalamic connectivity with frontal neocortex, these results suggest that the thalamus sends an early memory signal to frontal regions, triggering further memory search processes.

  17. Inhibition of Cathepsin B Alleviates Secondary Degeneration in Ipsilateral Thalamus After Focal Cerebral Infarction in Adult Rats.

    Science.gov (United States)

    Zuo, Xialin; Hou, Qinghua; Jin, Jizi; Zhan, Lixuan; Li, Xinyu; Sun, Weiwen; Lin, Kunqin; Xu, En

    2016-09-01

    Secondary degeneration in areas beyond ischemic foci can inhibit poststroke recovery. The cysteine protease Cathepsin B (CathB) regulates cell death and intracellular protein catabolism. To investigate the roles of CathB in the development of secondary degeneration in the ventroposterior nucleus (VPN) of the ipsilateral thalamus after focal cerebral infarction, infarct volumes, immunohistochemistry and immunofluorescence, and Western blotting analyses were conducted in a distal middle cerebral artery occlusion (dMCAO) stroke model in adult rats. We observed marked neuron loss and gliosis in the ipsilateral thalamus after dMCAO, and the expression of CathB and cleaved caspase-3 in the VPN was significantly upregulated; glial cells were the major source of CathB. Although it had no effect on infarct volume, delayed intracerebroventricular treatment with the membrane-permeable CathB inhibitor CA-074Me suppressed the expression of CathB and cleaved caspase-3 in ipsilateral VPN and accordingly alleviated the secondary degeneration. These data indicate that CathB mediates a novel mechanism of secondary degeneration in the VPN of the ipsilateral thalamus after focal cortical infarction and suggest that CathB might be a therapeutic target for the prevention of secondary degeneration in patients after stroke.

  18. Functional MRI activity in the thalamus and occipital cortex of anesthetized dogs induced by monocular and binocular stimulation.

    Science.gov (United States)

    Willis, C K; Quinn, R P; McDonell, W M; Gati, J; Partlow, G; Vilis, T

    2001-07-01

    The neuroanatomy of the mammalian visual system has received considerable attention through electrophysiological study of cats and non-human primates, and through neuroimaging of humans. Canine neuroanatomy, however, has received much less attention, limiting our understanding of canine vision and visual pathways. As an early step in applying blood oxygenation level dependant (BOLD) functional magnetic resonance imaging (fMRI) for veterinary use, we compared visual activity in the thalamus and occipital cortex of anesthetized dogs presented with binocular and monocular visual stimuli. Activity in the left and right thalamus and occipital cortex during monocular stimulation was also compared. Six beagles were presented with a vertical grating visual stimulus and scanned at 4 Tesla. Each dog was scanned twice under each of 3 anesthetic protocols (isoflurane, propofol, and fentanyl/midazolam). We found: 1) significant BOLD activation in the lateral geniculate nucleus (LGN) of the thalamus and the occipital cortex; 2) a significantly larger area of activation in the LGN during monocular stimulation than during binocular stimulation; and 3) that activity in the hemisphere contralateral to the stimulus was not significantly greater than that ipsilateral to it. PMID:11480525

  19. Cerebrolysin reduces amyloid-β deposits, apoptosis and autophagy in the thalamus and improves functional recovery after cortical infarction.

    Science.gov (United States)

    Xing, Shihui; Zhang, Jian; Dang, Chao; Liu, Gang; Zhang, Yusheng; Li, Jingjing; Fan, Yuhua; Pei, Zhong; Zeng, Jinsheng

    2014-02-15

    Focal cerebral infarction causes amyloid-β (Aβ) deposits and secondary thalamic neuronal degeneration. The present study aimed to determine the protective effects of Cerebrolysin on Aβ deposits and secondary neuronal damage in thalamus after cerebral infarction. At 24h after distal middle cerebral artery occlusion (MCAO), Cerebrolysin (5 ml/kg) or saline as control was once daily administered for consecutive 13 days by intraperitoneal injection. Sensory function and secondary thalamic damage were assessed with adhesive-removal test, Nissl staining and immunofluorescence at 14 days after MCAO. Aβ deposits, activity of β-site amyloid precursor protein-cleaving enzyme 1 (BACE1), apoptosis and autophagy were determined by TUNEL staining, immunofluorescence and immunoblot. The results showed that Cerebrolysin significantly improved sensory deficit compared to controls (pCerebrolysin, which was accompanied by decreases in neuronal loss and astroglial activation compared to controls (all p Cerebrolysin markedly inhibited cleaved caspase-3, conversion of LC3-II, downregulation of Bcl-2 and upregulation of Bax in the ipsilateral thalamus compared to controls (all pCerebrolysin reduces Aβ deposits, apoptosis and autophagy in the ipsilateral thalamus, which may be associated with amelioration of secondary thalamic damage and functional recovery after cerebral infarction.

  20. Expression of Cystic Fibrosis Transmembrane Conductance Regulator in Ganglia of Human Gastrointestinal Tract

    Science.gov (United States)

    Xue, Ruiqi; Gu, Huan; Qiu, Yamei; Guo, Yong; Korteweg, Christine; Huang, Jin; Gu, Jiang

    2016-01-01

    CF is caused by mutations of the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) which is an anion selective transmembrane ion channel that mainly regulates chloride transport, expressed in the epithelia of various organs. Recently, we have demonstrated CFTR expression in the brain, the spinal cord and the sympathetic ganglia. This study aims to investigate the expression and distribution of CFTR in the ganglia of the human gastrointestinal tract. Fresh tissue and formalin-fixed paraffin-embedded normal gastrointestinal tract samples were collected from eleven surgical patients and five autopsy cases. Immunohistochemistry, in situ hybridization, laser-assisted microdissection and nested reverse transcriptase polymerase chain reaction were performed. Expression of CFTR protein and mRNA was detected in neurons of the ganglia of all segments of the human gastrointestinal tract examined, including the stomach, duodenum, jejunum, ileum, cecum, appendix, colon and rectum. The extensive expression of CFTR in the enteric ganglia suggests that CFTR may play a role in the physiology of the innervation of the gastro-intestinal tract. The presence of dysfunctional CFTRs in enteric ganglia could, to a certain extent, explain the gastrointestinal symptoms frequently experienced by CF patients. PMID:27491544

  1. Expression of Cystic Fibrosis Transmembrane Conductance Regulator in Ganglia of Human Gastrointestinal Tract.

    Science.gov (United States)

    Xue, Ruiqi; Gu, Huan; Qiu, Yamei; Guo, Yong; Korteweg, Christine; Huang, Jin; Gu, Jiang

    2016-01-01

    CF is caused by mutations of the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) which is an anion selective transmembrane ion channel that mainly regulates chloride transport, expressed in the epithelia of various organs. Recently, we have demonstrated CFTR expression in the brain, the spinal cord and the sympathetic ganglia. This study aims to investigate the expression and distribution of CFTR in the ganglia of the human gastrointestinal tract. Fresh tissue and formalin-fixed paraffin-embedded normal gastrointestinal tract samples were collected from eleven surgical patients and five autopsy cases. Immunohistochemistry, in situ hybridization, laser-assisted microdissection and nested reverse transcriptase polymerase chain reaction were performed. Expression of CFTR protein and mRNA was detected in neurons of the ganglia of all segments of the human gastrointestinal tract examined, including the stomach, duodenum, jejunum, ileum, cecum, appendix, colon and rectum. The extensive expression of CFTR in the enteric ganglia suggests that CFTR may play a role in the physiology of the innervation of the gastro-intestinal tract. The presence of dysfunctional CFTRs in enteric ganglia could, to a certain extent, explain the gastrointestinal symptoms frequently experienced by CF patients. PMID:27491544

  2. Anatomia microcirúgica da substâcia perfurada anterior basal humana Microsurgical anatomy of the human basal anterior perforated substance

    Directory of Open Access Journals (Sweden)

    Arlindo Alfredo Silveira D’Ávila

    2006-06-01

    Full Text Available A substância perfurada anterior constitui referencial na base do encéfalo. Localizada acima da bifurcação subaracnóidea da artéria carótida interna em sua porção basal e junto à artéria comunicante anterior na face inter-hemisférica, é transfixada por ramos perfurantes dirigidos aos núcleos telencefálicos corticais, cápsula interna e parte do tálamo. Por injeção intravascular de gelatina carminada, resina de Batson e látex, analisamos 50 hemisférios cerebrais humanos adultos de ambos os sexos, sob o microscópio cirúrgico. Objetivamos contribuir para a determinação da origem, número e topografia dos ramos destinados a essa região, seu curso, anastomoses e territórios de penetração. Propusemo-nos também a analisar a contribuição da artéria comunicante anterior à substância perfurada anterior. Foram encontradas variações anatômicas, incluindo anastomoses, envolvendo principalmente a artéria cerebral média e a artéria coróidea anterior. Estes conhecimentos são de interesse clínico-cirúrgico em razão da freqüência de patologias vasculares e tumorais a ela relacionadas.The anterior perforated substance (APS is a landmark in the basal forebrain. It has a basal face located above the carotid bifurcation in the subarachnoid space, and an interhemispheric one. It is the site of passage of the arteries to the caudate nucleus, putamen, internal capsule, adjacent areas of the globus pallidus and thalamus. Fifty hemispheres from twenty-five adult cadavers were obtained. The arteries were perfused with colored latex, Batson’s resin and gelatin colored with carmine. Using a surgical microscope we have determined the origin, local and number of origin from the parent vessel. The sites of penetration in the mediolateral and anteroposterior direction were also recorded. The anterior communicating artery contribution to the basal APS was reviewed. Significant vascular variations and anastomoses were encountered

  3. Lesions of the posterior paraventricular nucleus of the thalamus attenuate fear expression

    Directory of Open Access Journals (Sweden)

    Yonghui eLi

    2014-03-01

    Full Text Available The paraventricular nucleus of the thalamus (PVT has generated interest because of its strong projections to areas of the brain associated with the regulation of emotional behaviors. The posterior aspect of the PVT (pPVT is notable for its projection to the central nucleus of the amygdala which is essential for the expression of a conditioned fear response. The present study was done to determine if the pPVT is involved in the expression of fear by examining the effect of post-conditioning lesions of the pPVT. Male rats were trained to bar press for food pellets on a variable ratio schedule. Fear conditioning was done using auditory tones (30 s that co-terminate with footschocks (0.65 mA, 1.0 s. Rats were anesthetized 24 hours later and small bilateral electrolytic lesions of the pPVT were made. Fear expression to the tone was assessed using suppression of bar-pressing and freezing after one week of recovery from the surgical procedure. Small bilateral lesions of the pPVT increased bar-pressing for food and decreased freezing during the presentation of the conditioned tone. Lesions of the pPVT had no effect on fear extinction, fear conditioning to a novel tone, or the motivation for food as assessed using a progressive ratio schedule. The results of the experiment support a role for the pPVT in fear expression. In contrast, the pPVT does not appear to be involved in fear learning or extinction nor does it appear to play a role in the motivation of rats to bar press for food.

  4. Thalamic reticular nucleus in Caiman crocodilus: Relationship with the dorsal thalamus.

    Science.gov (United States)

    Pritz, M B

    2016-05-13

    The thalamic reticular nucleus was investigated in one group of crocodilians, Caiman crocodilus. This neuronal aggregate is composed of two parts: a compact portion and a diffuse region made up of scattered cells within the forebrain bundles. In Caiman, both the lateral and medial forebrain bundles project to the telencephalon and the thalamic reticular nucleus is associated with each fiber tract. In the lateral forebrain bundle, the compact area is termed the nucleus of the dorsal peduncle (dorsal peduncular nucleus) while the diffuse part is called the perireticular area. In the medial forebrain bundle, the interstitial nucleus comprises one part of the compact area while another region without a specific neuronal label is also present. Similar to the perireticular cells of the lateral forebrain bundle, scattered cells are also present in the medial forebrain bundle. Morphological features of the thalamic reticular nucleus are revealed with stains for the following: fibers; cells; succinic acid dehydrogenase; and acetylcholinesterase. Regardless of which dorsal thalamic nucleus was injected, a localized region of the thalamic reticular nucleus contained retrogradely labeled cells and anterogradely labeled axons and terminals. This grouping was termed clusters and was felt to represent the densest interconnection between the dorsal thalamus and the reticular nucleus. Using clusters as an index of interconnections, the reticular nucleus was divided into sectors, each of which was associated with a specific dorsal thalamic nucleus. An organization similar to that found in Caiman is present in other sauropsids as well as in mammals. These data suggest that a thalamic reticular nucleus is present in all amniotes and has morphological properties similar to those described in this analysis. Lastly, a hypothesis is presented to explain how the external shape of the reticular nucleus in Caiman might be transformed into the homologous area in a representative bird and

  5. Accelerated Echo Planer J-resolved Spectroscopic Imaging of Putamen and Thalamus in Obstructive Sleep Apnea

    Science.gov (United States)

    Sarma, Manoj K.; Macey, Paul M.; Nagarajan, Rajakumar; Aysola, Ravi; Harper, Ronald M.; Thomas, M. Albert

    2016-01-01

    Obstructive sleep apnea syndrome (OSAS) leads to neurocognitive and autonomic deficits that are partially mediated by thalamic and putamen pathology. We examined the underlying neurochemistry of those structures using compressed sensing-based 4D echo-planar J-resolved spectroscopic imaging (JRESI), and quantified values with prior knowledge fitting. Bilaterally increased thalamic mI/Cr, putamen Glx/Cr, and Glu/Cr, and bilaterally decreased thalamic and putamen tCho/Cr and GABA/Cr occurred in OSAS vs healthy subjects (p < 0.05). Increased right thalamic Glx/Cr, Glu/Cr, Gln/Cr, Asc/Cr, and decreased GPC/Cr and decreased left thalamic tNAA/Cr, NAA/Cr were detected. The right putamen showed increased mI/Cr and decreased tCho/Cr, and the left, decreased PE/Cr ratio. ROC curve analyses demonstrated 60–100% sensitivity and specificity for the metabolite ratios in differentiating OSAS vs. controls. Positive correlations were found between: left thalamus mI/Cr and baseline oxygen saturation (SaO2); right putamen tCho/Cr and apnea hypopnea index; right putamen GABA/Cr and baseline SaO2; left putamen PE/Cr and baseline SaO2; and left putamen NAA/Cr and SaO2 nadir (all p < 0.05). Negative correlations were found between left putamen PE/Cr and SaO2 nadir. These findings suggest underlying inflammation or glial activation, with greater alterations accompanying lower oxygen saturation. These metabolite levels may provide biomarkers for future neurochemical interventions by pharmacologic or other means. PMID:27596614

  6. The thalamus as a low pass filter: filtering at the cellular level does not equate with filtering at the network level.

    Directory of Open Access Journals (Sweden)

    William Martin Connelly

    2016-01-01

    Full Text Available In the mammalian central nervous system, most sensory information passes through primary sensory thalamic nuclei, however the consequence of this remains unclear. Various propositions exist, likening the thalamus to a gate, or a high pass filter. Here, using a simple leaky integrate and fire model based on physiological parameters, we show that the thalamus behaves akin to a low pass filter. Specifically, as individual cells in the thalamus rely on consistent drive to spike, stimuli that is rapidly and continuously changing over time such that it activates sensory cells with different receptive fields are unable to drive thalamic spiking. This means that thalamic encoding is robust to sensory noise, however it induces a lag in sensory representation. Thus the thalamus stabilises encoding of sensory information, at the cost of response rate.

  7. Organization of the Zone of Transition between the Pretectum and the Thalamus, with Emphasis on the Pretectothalamic Lamina.

    Science.gov (United States)

    Márquez-Legorreta, Emmanuel; Horta-Júnior, José de Anchieta C; Berrebi, Albert S; Saldaña, Enrique

    2016-01-01

    The zone of transition between the pretectum, derived from prosomere 1, and the thalamus, derived from prosomere 2, is structurally complex and its understanding has been hampered by cytoarchitectural and terminological confusion. Herein, using a battery of complementary morphological approaches, including cytoarchitecture, myeloarchitecture and the expression of molecular markers, we pinpoint the features or combination of features that best characterize each nucleus of the pretectothalamic transitional zone of the rat. Our results reveal useful morphological criteria to identify and delineate, with unprecedented precision, several [mostly auditory] nuclei of the posterior group of the thalamus, namely the pretectothalamic lamina (PTL; formerly known as the posterior limitans nucleus), the medial division of the medial geniculate body (MGBm), the suprageniculate nucleus (SG), and the ethmoid, posterior triangular and posterior nuclei of the thalamus. The PTL is a sparsely-celled and fiber rich flattened nucleus apposed to the lateral surface of the anterior pretectal nucleus (APT) that marks the border between the pretectum and the thalamus; this structure stains selectively with the Wisteria floribunda agglutinin (WFA), and is essentially immunonegative for the calcium binding protein parvalbumin (PV). The MGBm, located medial to the ventral division of the MGB (MGBv), can be unequivocally identified by the large size of many of its neurons, its dark immunostaining for PV, and its rather selective staining for WFA. The SG, which extends for a considerable caudorostral distance and deviates progressively from the MGB, is characterized by its peculiar cytoarchitecture, the paucity of myelinated fibers, and the conspicuous absence of staining for calretinin (CR); indeed, in many CR-stained sections, the SG stands out as a blank spot. Because most of these nuclei are small and show unique anatomical relationships, the information provided in this article will

  8. Computer Modelling of Neuronal Interactions in the Striatum

    OpenAIRE

    Hjorth, Johannes

    2009-01-01

    Large parts of the cortex and the thalamus project into the striatum,which serves as the input stage of the basal ganglia. Information isintegrated in the striatal neural network and then passed on, via themedium spiny (MS) projection neurons, to the output stages of thebasal ganglia. In addition to the MS neurons there are also severaltypes of interneurons in the striatum, such as the fast spiking (FS)interneurons. I focused my research on the FS neurons, which formstrong inhibitory synapses...

  9. Localized basal meningeal enhancement in tuberculous meningitis

    Energy Technology Data Exchange (ETDEWEB)

    Theron, Salomine; Andronikou, Savvas; Grobbelaar, Marie; Steyn, Freda; Mapukata, Ayanda; Plessis, Jaco du [University of Stellenbosch, Department of Radiology, Tygerberg Hospital, P.O. BOX 19063, Tygerberg (South Africa)

    2006-11-15

    Focal basal meningeal enhancement may produce a confusing CT picture in children with suspected tuberculous meningitis (TBM). To demonstrate the incidence, distribution and appearance of localized basal meningeal enhancement in children with TBM. CT scans of patients with definite (culture proven) and probable (CSF suggestive) TBM were retrospectively evaluated by two observers. Localized basal enhancement was documented as involving: unilateral cistern of the lateral fossa (CLF), unilateral sylvian fissure, unilateral CLF and sylvian fissure in combination, unilateral CLF and sylvian fissure with ipsi- or contralateral ambient cistern and isolated quadrigeminal plate cistern. The study included 130 patients with TBM (aged 2 months to 13 years 9 months). Focal basal enhancement was seen in 11 patients (8.5%). The sylvian fissure was involved most commonly, followed by the lateral fossa cistern. The ambient cistern was involved in three patients and the quadrigeminal plate cistern in one. Focal areas of enhancement corresponded to the areas of infarction in every patient. Focal basal meningeal enhancement is common (8.5%) in paediatric TBM. This must be kept in mind when evaluating CT scans in children presenting with focal neurological findings, seizures or meningism in communities where TBM is endemic. (orig.)

  10. Functional characterization and expression of thalamic GABA(B) receptors in a rodent model of Parkinson's disease

    NARCIS (Netherlands)

    de Groote, C; Wullner, U; Loschmann, PA; Luiten, PGM; Klockgether, T

    1999-01-01

    Increased GABAergic neurotransmission of the basal ganglia output nuclei projecting to the motor thalamus is thought to contribute to the pathophysiology of Parkinson's disease. We investigated the functional role of thalamic GABA(B) receptors in a rodent model of Parkinson's disease. First, we exam

  11. Structural Connectivity in Gilles de la Tourette Syndrome

    Directory of Open Access Journals (Sweden)

    Ana B Chelse

    2015-04-01

    Full Text Available Investigators from Centre de Reference National Maladie Rare ‘Syndrome Gilles de la Tourette’ and Sorbonne University report white matter abnormalities in the pathways connecting the cerebral cortex, basal ganglia, and thalamus in a group of 49 adults with Tourette syndrome (TS.

  12. Radiologic study of basal cell nevus syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Park, Tae Won [Dept. of Oral Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1988-11-15

    Several cases of jaw cyst-basal cell nevus-bifid rib syndrome are presented. This syndrome consists principally of multiple jaw cysts, basal cell nevi, and bifid ribs but no one component is present in all patients. The purpose of this paper is to review the multiple characteristics of this syndrome and present three cases in a family and additional 4 cases. The many malformations associated with the syndrome have variable expressively. In the cases, multiple jaw cysts, pal mar and plantar pittings, bridging of sella, temporoparietal bossing, hypertelorism, cleft palate, and dystopia canthoru m have been observed.

  13. Basal Cell Carcinoma in a Child

    OpenAIRE

    Samet Vasfi Kuvat; Zuhal Gücin; Barış Keklik; Gülzade Özyalvaçlı; Karaca Başaran

    2011-01-01

    Basal cell carcinoma is the most commonly seen nonmelanoma skin cancer which is rarely encountered in the childhood period. An 11-year old child was admitted to our clinic due to an erythematous and a slightly pigmented lesion with a 3 × 4 cm diameter on his posterior scalp. Macroscopically, the lesion was excised with a 10 mm safety margin. Pathologic examination revealed a basal cell carcinoma. No symptoms or signs of a syndrome were observed both in the patient and his family.

  14. RNA-Seq Analysis of Human Trigeminal and Dorsal Root Ganglia with a Focus on Chemoreceptors.

    Directory of Open Access Journals (Sweden)

    Caroline Flegel

    Full Text Available The chemosensory capacity of the somatosensory system relies on the appropriate expression of chemoreceptors, which detect chemical stimuli and transduce sensory information into cellular signals. Knowledge of the complete repertoire of the chemoreceptors expressed in human sensory ganglia is lacking. This study employed the next-generation sequencing technique (RNA-Seq to conduct the first expression analysis of human trigeminal ganglia (TG and dorsal root ganglia (DRG. We analyzed the data with a focus on G-protein coupled receptors (GPCRs and ion channels, which are (potentially involved in chemosensation by somatosensory neurons in the human TG and DRG. For years, transient receptor potential (TRP channels have been considered the main group of receptors for chemosensation in the trigeminal system. Interestingly, we could show that sensory ganglia also express a panel of different olfactory receptors (ORs with putative chemosensory function. To characterize OR expression in more detail, we performed microarray, semi-quantitative RT-PCR experiments, and immunohistochemical staining. Additionally, we analyzed the expression data to identify further known or putative classes of chemoreceptors in the human TG and DRG. Our results give an overview of the major classes of chemoreceptors expressed in the human TG and DRG and provide the basis for a broader understanding of the reception of chemical cues.

  15. Restricted varicella-zoster virus transcription in human trigeminal ganglia obtained soon after death

    NARCIS (Netherlands)

    W.J.D. Ouwendijk (Werner ); A. Choe (Alexander); M.A. Nagel (Maria ); D. Gilden (Don); A.D.M.E. Osterhaus (Albert); R.J. Cohrs (Randall ); G.M.G.M. Verjans (George)

    2012-01-01

    textabstractWe analyzed the varicella-zoster virus (VZV) transcriptome in 43 latently infected human trigeminal ganglia (TG) with postmortem intervals (PMIs) ranging from 3.7 to 24 h. Multiplex reverse transcriptase PCR (RT-PCR) revealed no VZV transcripts with a PMI of <9 h. Real-time PCR indicated

  16. Respiratory Responses to Stimulation of Branchial Vagus Nerve Ganglia of a Teleost Fish

    NARCIS (Netherlands)

    Ballintijn, C.M.; Luiten, P.G.M.

    1983-01-01

    The effects of electrical stimulation of epibranchial vagus ganglia upon respiration of the carp were investigated. Single shocks evoked fast twitch responses in a number of respiratory muscles with latencies around 18 msec to the beginning and 30-35 msec to the peak of activity. Shocks given during

  17. RNA-Seq Analysis of Human Trigeminal and Dorsal Root Ganglia with a Focus on Chemoreceptors.

    Science.gov (United States)

    Flegel, Caroline; Schöbel, Nicole; Altmüller, Janine; Becker, Christian; Tannapfel, Andrea; Hatt, Hanns; Gisselmann, Günter

    2015-01-01

    The chemosensory capacity of the somatosensory system relies on the appropriate expression of chemoreceptors, which detect chemical stimuli and transduce sensory information into cellular signals. Knowledge of the complete repertoire of the chemoreceptors expressed in human sensory ganglia is lacking. This study employed the next-generation sequencing technique (RNA-Seq) to conduct the first expression analysis of human trigeminal ganglia (TG) and dorsal root ganglia (DRG). We analyzed the data with a focus on G-protein coupled receptors (GPCRs) and ion channels, which are (potentially) involved in chemosensation by somatosensory neurons in the human TG and DRG. For years, transient receptor potential (TRP) channels have been considered the main group of receptors for chemosensation in the trigeminal system. Interestingly, we could show that sensory ganglia also express a panel of different olfactory receptors (ORs) with putative chemosensory function. To characterize OR expression in more detail, we performed microarray, semi-quantitative RT-PCR experiments, and immunohistochemical staining. Additionally, we analyzed the expression data to identify further known or putative classes of chemoreceptors in the human TG and DRG. Our results give an overview of the major classes of chemoreceptors expressed in the human TG and DRG and provide the basis for a broader understanding of the reception of chemical cues. PMID:26070209

  18. Consistent phosphenes generated by electrical microstimulation of the visual thalamus. An experimental approach for thalamic visual neuroprostheses

    Directory of Open Access Journals (Sweden)

    Fivos ePanetsos

    2011-07-01

    Full Text Available Most work on visual prostheses has centred on developing retinal or cortical devices. However, when retinal implants are not feasible, neuroprostheses could be implanted in the lateral geniculate nucleus of the thalamus (LGN, the intermediate relay station of visual information from the retina to the visual cortex (V1. The objective of the present study was to determine the types of artificial stimuli that when delivered to the visual thalamus can generate reliable responses of the cortical neurons similar to those obtained when the eye perceives a visual image. Visual stimuli {Si} were presented to one eye of an experimental animal and both, the thalamic {RThi} and cortical responses {RV1i} to such stimuli were recorded. Electrical patterns {RThi*} resembling {RThi} were then injected into the visual thalamus to obtain cortical responses {RV1i*} similar to {RV1i}. Visually- and electrically-generated V1 responses were compared.Results: During the course of this work we: (i characterised the response of V1 neurons to visual stimuli according to response magnitude, duration, spiking rate and the distribution of interspike intervals; (ii experimentally tested the dependence of V1 responses on stimulation parameters such as intensity, frequency, duration, etc. and determined the ranges of these parameters generating the desired cortical activity; (iii identified similarities between responses of V1 useful to compare the naturally and artificially generated neuronal activity of V1; and (iv by modifying the stimulation parameters, we generated artificial V1 responses similar to those elicited by visual stimuli.Generation of predictable and consistent phosphenes by means of artificial stimulation of the LGN is important for the feasibility of visual prostheses. Here we proved that electrical stimuli to the LGN can generate V1 neural responses that resemble those elicited by natural visual stimuli.

  19. Immunohistochemical detection of ganglia in the rat stomach serosa, containing neurons immunoreactive for gastrin-releasing peptide and vasoactive intestinal peptide

    DEFF Research Database (Denmark)

    Poulsen, Steen Seier; Holst, J J

    1987-01-01

    Ganglia, not previously described, were identified in the rat stomach serosa along the minor curvature. The ganglia consisted of varying number of cell bodies lying in clusters along or within nerve bundles. The ganglia were shown to contain GRP and VIP immunoreactive nerve fibers and cell bodies...... and also some NPY immunoreactive fibers, whereas they were devoid of somatostatin immunoreactivity. Nerve ligation experiments indicated that the ganglia are intrinsic to the stomach....

  20. Teaching Social Studies Using Basal Readers.

    Science.gov (United States)

    Garcia, Jesus; Logan, John W.

    1983-01-01

    A lesson, "Harriet Tubman: A Most Successful Conductor," illustrates how to employ a basal reader in social studies instruction in the elementary grades. This approach offers students a relevant curriculum, greater opportunities for concept development, practice in skills areas, and activities that offer greater opportunity to master social…

  1. Basal Cell Carcinoma in The Netherlands

    NARCIS (Netherlands)

    S.C. Flohil (Sophie)

    2012-01-01

    textabstractThere are many different cutaneous malignancies, but malignant melanoma, squamous cell carcinoma (SCC) and basal cell carcinoma (BCC) represent approximately 98% of all skin cancers.In literature, these three skin cancers are often divided into melanoma and nonmelanoma skin cancers (NMSC

  2. Connections between the thalamus and the somatosensory areas of the anterior ectosylvian gyrus in the cat.

    Science.gov (United States)

    Burton, H; Kopf, E M

    1984-04-01

    The thalamocortical and corticothalamic connections of the second somatic sensory area (SII) and adjacent cortical areas in the cat were studied with anterograde and retrograde tracers. Injections consisted of horseradish peroxidase conjugated to wheat germ agglutinin (HRP-WGA) or a mixture of equal parts of tritiated leucine and proline. The cortical regions to be injected were electrophysiologically studied with microelectrodes to determine the localization of the selected components of the body representation in SII. The distribution of recording points was correlated in each case with the extent of the injection mass in the cortex. Distributions of retrograde and anterograde labeling in the thalamus were reconstructed from serial coronal sections. The results from cases with injections of tracers exclusively confined to separate parts of the body map in SII indicated a fairly precise topographical organization of projections from the ventrobasal complex (VB) to SII. The labeled cells and fibers were located within a series of lamella-like rods that curved throughout the dorsoventral and rostrocaudal axis of VB. The position and extent of these lamellae shifted from medial and ventral, in the medial subdivision of ventral posterior lateral nucleus (VPLm) for radial forelimb digit zones of SII, to dorsal, posterior, and lateral, in the lateral subdivision of ventral posterior lateral nucleus (VPL1) for proximal leg and trunk regions in SII. For every injected area in SII the densest clustering of labeled cells and fibers was usually more posteriorly represented in VB. The distribution in these dense zones of labeling often extended through the central core of VB. SII projecting neurons were also consistently noted in the extreme rostral portion of the medial subdivision of the posterior nuclei (Pom) that lies dorsal to VB. Corticothalamic and thalamocortical connections for SII were entirely reciprocal. Injections of tracers into cortical areas surrounding SII

  3. Surgical excision of wrist ganglia; literature review and nine-year retrospective study of recurrence and patient satisfaction

    Directory of Open Access Journals (Sweden)

    Surjit Lidder

    2009-06-01

    Full Text Available The main options for the treatment of wrist ganglia are reassurance, aspiration, arthroscopic resection and open excision. Variations within each option have been described and the literature is clouded by widespread variability in the results reported. We present the results of our own long-term retrospective study, review the literature and question the surgical risks and demands placed on healthcare resources. A retrospective review of the surgical results of dorsal and volar wrist ganglia excision between January 1998 and March 2005 was undertaken at a single institution. Of the 152 patients in this consecutive series, 117 (77% patients responded to a telephone questionnaire. The mean length of follow-up in this series of 117 patients was 4.2 years (range 1.5-8.7 years. The overall recurrence rate following excision of all wrist ganglia in this series was 41.8 %. When looking just at volar ganglia, the risk of recurrence is higher at 46.8%. Should the ganglion recur, the risk of developing a moderate to severely tender scar is 34.6% and the risk of developing an unsightly scar is 8.2%. This study questions the effectiveness of surgical excision in the treatment of wrist ganglia when performed by a mixture of surgeons in that the recurrence rates are very similar to the rates seen in studies that merely observe or aspirate wrist ganglia. We propose that for symptomatic ganglia, specialists in hand surgery may be more appropriate at treating such a pathology.

  4. Resting-state functional connectivity between the dorsal anterior cingulate cortex and thalamus is associat