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File list: His.Neu.50.AllAg.Thalamic_Nuclei [Chip-atlas[Archive

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File list: His.Neu.20.AllAg.Thalamic_Nuclei [Chip-atlas[Archive

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Holmes’ Tremor with Shoulder Pain Treated by Deep Brain Stimulation of Unilateral Ventral Intermediate Thalamic Nucleus and Globus Pallidus Internus

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Sabri Aydın

2017-05-01

Full Text Available A 21-year-old male was admitted with severe right arm and hand tremors after a thalamic hemorrhage caused by a traffic accident. He was also suffering from agonizing pain in his right shoulder that manifested after the tremor. Neurologic examination revealed a disabling, severe, and irregular kinetic and postural tremor in the right arm during target-directed movements. There was also an irregular ipsilateral rest tremor and dystonic movements in the distal part of the right arm. The amplitude was moderate at rest and extremely high during kinetic and intentional movements. The patient underwent left globus pallidum internus and ventral intermediate thalamic nucleus deep brain stimulation. The patient improved by more than 80% as rated by the Fahn-Tolosa-Marin Tremor Rating Scale and Visual Analog Scale six months after surgery.

Different expressions of high voltage-activated Ca2+ channel types in the rostral reticular thalamic nucleus of the absence epileptic WAG/Rij rat.

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Bovenkamp-Janssen, M.C. van de; Scheenen, W.J.J.M.; Kuijpers-Kwant, F.J.; Kozicz, L.T.; Veening, J.G.; Luijtelaar, E.L.J.M. van; McEnery, M.W.; Roubos, E.W.

2004-01-01

In the WAG/Rij rat, a model for human absence epilepsy, spike-wave discharges (SWD) and absence epileptic behavior develop after the age of 3 months. The rostral part of the reticular thalamic nucleus (rRTN) is involved in SWD. Ca(2+) channels play a central role in the initiation and maintenance of

The Medial Dorsal Thalamic Nucleus and the Medial Prefrontal Cortex of the Rat Function Together to Support Associative Recognition and Recency but Not Item Recognition

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Cross, Laura; Brown, Malcolm W.; Aggleton, John P.; Warburton, E. Clea

2013-01-01

In humans recognition memory deficits, a typical feature of diencephalic amnesia, have been tentatively linked to mediodorsal thalamic nucleus (MD) damage. Animal studies have occasionally investigated the role of the MD in single-item recognition, but have not systematically analyzed its involvement in other recognition memory processes. In…

Visuomotor signals for reaching movements in the rostro-dorsal sector of the monkey thalamic reticular nucleus.

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Saga, Yosuke; Nakayama, Yoshihisa; Inoue, Ken-Ichi; Yamagata, Tomoko; Hashimoto, Masashi; Tremblay, Léon; Takada, Masahiko; Hoshi, Eiji

2017-05-01

The thalamic reticular nucleus (TRN) collects inputs from the cerebral cortex and thalamus and, in turn, sends inhibitory outputs to the thalamic relay nuclei. This unique connectivity suggests that the TRN plays a pivotal role in regulating information flow through the thalamus. Here, we analyzed the roles of TRN neurons in visually guided reaching movements. We first used retrograde transneuronal labeling with rabies virus, and showed that the rostro-dorsal sector of the TRN (TRNrd) projected disynaptically to the ventral premotor cortex (PMv). In other experiments, we recorded neurons from the TRNrd or PMv while monkeys performed a visuomotor task. We found that neurons in the TRNrd and PMv showed visual-, set-, and movement-related activity modulation. These results indicate that the TRNrd, as well as the PMv, is involved in the reception of visual signals and in the preparation and execution of reaching movements. The fraction of neurons that were non-selective for the location of visual signals or the direction of reaching movements was greater in the TRNrd than in the PMv. Furthermore, the fraction of neurons whose activity increased from the baseline was greater in the TRNrd than in the PMv. The timing of activity modulation of visual-related and movement-related neurons was similar in TRNrd and PMv neurons. Overall, our data suggest that TRNrd neurons provide motor thalamic nuclei with inhibitory inputs that are predominantly devoid of spatial selectivity, and that these signals modulate how these nuclei engage in both sensory processing and motor output during visually guided reaching behavior. © 2016 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

Neural signal for counteracting pre-action bias in the centromedian thalamic nucleus

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Takafumi eMinamimoto

2014-01-01

Full Text Available Most of our daily actions are selected and executed involuntarily under familiar situations by the guidance of internal drives, such as motivation. The behavioral tendency or biasing towards one over others reflects the action-selection process in advance of action execution (i.e., pre-action bias. Facing unexpected situations, however, pre-action bias should be withdrawn and replaced by an alternative that is suitable for the situation (i.e., counteracting bias. To understand the neural mechanism for the counteracting process, we studied the neural activity of the thalamic centromedian (CM nucleus in monkeys performing GO-NOGO task with asymmetrical or symmetrical reward conditions. The monkeys reacted to GO signal faster in large-reward condition, indicating behavioral bias toward large reward. In contrast, they responded slowly in small-reward condition, suggesting a conflict between internal drive and external demand. We found that neurons in the CM nucleus exhibited phasic burst discharges after GO and NOGO instructions especially when they were associated with small reward. The small-reward preference was positively correlated with the strength of behavioral bias toward large reward. The small-reward preference disappeared when only NOGO action was requested. The timing of activation predicted the timing of action opposed to bias. These results suggest that CM signals the discrepancy between internal pre-action bias and external demand, and mediates the counteracting process — resetting behavioral bias and leading to execution of opposing action.

Thalamic morphology in schizophrenia and schizoaffective disorder.

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Smith, Matthew J; Wang, Lei; Cronenwett, Will; Mamah, Daniel; Barch, Deanna M; Csernansky, John G

2011-03-01

Biomarkers are needed that can distinguish between schizophrenia and schizoaffective disorder to inform the ongoing debate over the diagnostic boundary between these two disorders. Neuromorphometric abnormalities of the thalamus have been reported in individuals with schizophrenia and linked to core features of the disorder, but have not been similarly investigated in individuals with schizoaffective disorder. In this study, we examine whether individuals with schizoaffective disorder have a pattern of thalamic deformation that is similar or different to the pattern found in individuals with schizophrenia. T1-weighted magnetic resonance images were collected from individuals with schizophrenia (n = 47), individuals with schizoaffective disorder (n = 15), and controls (n = 42). Large-deformation, high-dimensional brain mapping was used to obtain three-dimensional surfaces of the thalamus. Multiple analyses of variance were used to test for group differences in volume and measures of surface shape. Individuals with schizophrenia or schizoaffective disorder have similar thalamic volumes. Thalamic surface shape deformation associated with schizophrenia suggests selective involvement of the anterior and posterior thalamus, while deformations in mediodorsal and ventrolateral regions were observed in both groups. Schizoaffective disorder had distinct deformations in medial and lateral thalamic regions. Abnormalities distinct to schizoaffective disorder suggest involvement of the central and ventroposterior medial thalamus which may be involved in mood circuitry, dorsolateral nucleus which is involved in recall processing, and the lateral geniculate nucleus which is involved in visual processing. Copyright © 2010 Elsevier Ltd. All rights reserved.

Thalamic physiology of intentional essential tremor is more like cerebellar tremor than postural essential tremor

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Zakaria, R; Lenz, FA; Hua, S; Avin, BH; Liu, CC; Mari, Z

2013-01-01

The neuronal physiological correlates of clinical heterogeneity in human essential tremor are unknown. We now test the hypothesis that thalamic neuronal and EMG activities during intention essential tremor are similar to those of the intention tremor which is characteristic of cerebellar lesions. Thalamic neuronal firing was studied in a cerebellar relay nucleus (ventral intermediate, Vim) and in a pallidal relay nucleus (ventral oral posterior, Vop) during stereotactic surgery for the treatm...

Control of Somatosensory Cortical Processing by Thalamic Posterior Medial Nucleus: A New Role of Thalamus in Cortical Function.

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Carlos Castejon

Full Text Available Current knowledge of thalamocortical interaction comes mainly from studying lemniscal thalamic systems. Less is known about paralemniscal thalamic nuclei function. In the vibrissae system, the posterior medial nucleus (POm is the corresponding paralemniscal nucleus. POm neurons project to L1 and L5A of the primary somatosensory cortex (S1 in the rat brain. It is known that L1 modifies sensory-evoked responses through control of intracortical excitability suggesting that L1 exerts an influence on whisker responses. Therefore, thalamocortical pathways targeting L1 could modulate cortical firing. Here, using a combination of electrophysiology and pharmacology in vivo, we have sought to determine how POm influences cortical processing. In our experiments, single unit recordings performed in urethane-anesthetized rats showed that POm imposes precise control on the magnitude and duration of supra- and infragranular barrel cortex whisker responses. Our findings demonstrated that L1 inputs from POm imposed a time and intensity dependent regulation on cortical sensory processing. Moreover, we found that blocking L1 GABAergic inhibition or blocking P/Q-type Ca2+ channels in L1 prevents POm adjustment of whisker responses in the barrel cortex. Additionally, we found that POm was also controlling the sensory processing in S2 and this regulation was modulated by corticofugal activity from L5 in S1. Taken together, our data demonstrate the determinant role exerted by the POm in the adjustment of somatosensory cortical processing and in the regulation of cortical processing between S1 and S2. We propose that this adjustment could be a thalamocortical gain regulation mechanism also present in the processing of information between cortical areas.

MRI of paramedian thalamic stroke with sleep disturbance

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Loevblad, K.O.; Bassetti, C.; Mathis, J.; Schroth, G.

1997-01-01

The paramedian thalamus is believed to play an important role in the regulation of sleep, and disturbances of sleep regulation are known to occur in paramedian thalamic stroke (PTS). We examined 12 consecutive patients with PTS and sleep disturbance by MRI. Two distinct groups of patients could be defined: six presenting with severe hypersomnia (group 1) and six with slight sleepiness (group 2). On MRI, all patients had ischaemic lesions involving the paramedian thalamic nuclei, the centre of the lesions being the dorsomedial and centromedial thalamic nuclei. In group 1 the lesions were bilateral, butterfly-shaped infarcts involving the paramedian nuclei (three cases), or unilateral with an extension into the subthalamic nuclei. In group 2 the lesions were unilateral and limited to the paramedian nuclei, mainly the dorsomedial nucleus. Bilateral lesions can be attributed to a common origin in some cases for both paramedian thalamic arteries and the mesencephalic arteries. (orig.). With 5 figs

Two distinct populations of projection neurons in the rat lateral parafascicular thalamic nucleus and their cholinergic responsiveness.

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Beatty, J A; Sylwestrak, E L; Cox, C L

2009-08-04

The lateral parafascicular nucleus (lPf) is a member of the intralaminar thalamic nuclei, a collection of nuclei that characteristically provides widespread projections to the neocortex and basal ganglia and is associated with arousal, sensory, and motor functions. Recently, lPf neurons have been shown to possess different characteristics than other cortical-projecting thalamic relay neurons. We performed whole cell recordings from lPf neurons using an in vitro rat slice preparation and found two distinct neuronal subtypes that were differentiated by distinct morphological and physiological characteristics: diffuse and bushy. Diffuse neurons, which had been previously described, were the predominant neuronal subtype (66%). These neurons had few, poorly-branching, extended dendrites, and rarely displayed burst-like action potential discharge, a ubiquitous feature of thalamocortical relay neurons. Interestingly, we discovered a smaller population of bushy neurons (34%) that shared similar morphological and physiological characteristics with thalamocortical relay neurons of primary sensory thalamic nuclei. In contrast to other thalamocortical relay neurons, activation of muscarinic cholinergic receptors produced a membrane hyperpolarization via activation of M(2) receptors in most lPf neurons (60%). In a minority of lPf neurons (33%), muscarinic agonists produced a membrane depolarization via activation of predominantly M(3) receptors. The muscarinic receptor-mediated actions were independent of lPf neuronal subtype (i.e. diffuse or bushy neurons); however the cholinergic actions were correlated with lPf neurons with different efferent targets. Retrogradely-labeled lPf neurons from frontal cortical fluorescent bead injections primarily consisted of bushy type lPf neurons (78%), but more importantly, all of these neurons were depolarized by muscarinic agonists. On the other hand, lPf neurons labeled by striatal injections were predominantly hyperpolarized by muscarinic

Midline thalamic reuniens lesions improve executive behaviors.

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Prasad, J A; Abela, A R; Chudasama, Y

2017-03-14

The role of the thalamus in complex cognitive behavior is a topic of increasing interest. Here we demonstrate that lesions of the nucleus reuniens (NRe), a midline thalamic nucleus interconnected with both hippocampal and prefrontal circuitry, lead to enhancement of executive behaviors typically associated with the prefrontal cortex. Rats were tested on four behavioral tasks: (1) the combined attention-memory (CAM) task, which simultaneously assessed attention to a visual target and memory for that target over a variable delay; (2) spatial memory using a radial arm maze, (3) discrimination and reversal learning using a touchscreen operant platform, and (4) decision-making with delayed outcomes. Following NRe lesions, the animals became more efficient in their performance, responding with shorter reaction times but also less impulsively than controls. This change, combined with a decrease in perseverative responses, led to focused attention in the CAM task and accelerated learning in the visual discrimination task. There were no observed changes in tasks involving either spatial memory or value-based decision making. These data complement ongoing efforts to understand the role of midline thalamic structures in human cognition, including the development of thalamic stimulation as a therapeutic strategy for acquired cognitive disabilities (Schiff, 2008; Mair et al., 2011), and point to the NRe as a potential target for clinical intervention. Published by Elsevier Ltd.

Posterior Thalamic Nucleus Modulation of Tactile Stimuli Processing in Rat Motor and Primary Somatosensory Cortices

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Diana Casas-Torremocha

2017-09-01

Full Text Available Rodents move rhythmically their facial whiskers and compute differences between signals predicted and those resulting from the movement to infer information about objects near their head. These computations are carried out by a large network of forebrain structures that includes the thalamus and the primary somatosensory (S1BF and motor (M1wk cortices. Spatially and temporally precise mechanorreceptive whisker information reaches the S1BF cortex via the ventroposterior medial thalamic nucleus (VPM. Other whisker-related information may reach both M1wk and S1BF via the axons from the posterior thalamic nucleus (Po. However, Po axons may convey, in addition to direct sensory signals, the dynamic output of computations between whisker signals and descending motor commands. It has been proposed that this input may be relevant for adjusting cortical responses to predicted vs. unpredicted whisker signals, but the effects of Po input on M1wk and S1BF function have not been directly tested or compared in vivo. Here, using electrophysiology, optogenetics and pharmacological tools, we compared in adult rats M1wk and S1BF in vivo responses in the whisker areas of the motor and primary somatosensory cortices to passive multi-whisker deflection, their dependence on Po activity, and their changes after a brief intense activation of Po axons. We report that the latencies of the first component of tactile-evoked local field potentials in M1wk and S1BF are similar. The evoked potentials decrease markedly in M1wk, but not in S1BF, by injection in Po of the GABAA agonist muscimol. A brief high-frequency electrical stimulation of Po decreases the responsivity of M1wk and S1BF cells to subsequent whisker stimulation. This effect is prevented by the local application of omega-agatoxin, suggesting that it may in part depend on GABA release by fast-spiking parvalbumin (PV-expressing cortical interneurons. Local optogenetic activation of Po synapses in different

Neurological manifestations and PET studies of the thalamic vascular lesions

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Matsuda, Shinji; Kawamura, Mitsuru; Hirayama, Keizo

1995-01-01

We divided 38 patients with cerebrovascular disease of the thalamus into 5 groups according to the site of the thalamic lesions as confirmed by X-ray CT and/or MRI. In 16 patients, we examined the cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO 2 ) by positron emission tomography (PET). In the anteromedial thalamic lesion group, patients displayed disturbances of spontaneity, memory, reading and writing. CBF and CMRO 2 were decreased in the frontal, parietal and temporal lobes on the side of the lesion. In the dorsolateral thalamic lesion group, ataxic hemiparesis was a characteristic symptom. CBF and CMRO 2 were decreased in frontoparietal lobes on the side of the lesion. In the group with lesions confined to the nucleus ventralis posterioris thalami, the main symptoms were sensory disturbance, with cheiro-oral sensory syndrome being particularly evident. CBF and CMRO 2 were decreased in the parietal lobe on the side of the lesion. In the group with posterolateral thalamic lesions without pulvinar involvement, patients exhibited thalamic syndrome without thalamic pain. CBF and CMRO 2 were decreased in the frontoparietal and temporal lobes on the side of the lesion. In contrast, in the group with posterolateral thalamic lesions with pulvinar involvement, all patients showed thalamic pain. The decrease in CBF and CMRO 2 extended to the inferomedial region of the temporal lobe in addition to the area of decreased CBF and CMRO 2 observed in the group with posterolateral thalamic lesions without pulvinar involvement. Based on these results, we speculate that the neurological manifestations of thalamic vascular disease are associated with a decrease in cortical CBF and CMRO 2 secondary to the thalamic lesions. (author)

Thalamic VPM nucleus in the behaving monkey. III. Effects of reversible inactivation by lidocaine on thermal and mechanical discrimination.

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Duncan, G H; Bushnell, M C; Oliveras, J L; Bastrash, N; Tremblay, N

1993-11-01

1. The present study evaluates the necessity of the ventroposterior medial thalamic nucleus (VPM) for discrimination of the intensity of noxious heating, innocuous cooling, and innocuous tactile (airpuff) stimulation of the maxillary skin. 2. Two rhesus monkeys were trained to detect small differences (Lidocaine hydrochloride (2%) was microinjected into regions of thalamus where single-unit recordings had identified neuronal responses to the noxious heating and/or cooling stimuli. The effectiveness of the anesthetic blockade was monitored by multiunit recordings using microelectrodes positioned 1-3 mm from the orifice of the injection cannula. The monkey's ability to detect near-threshold changes in stimulus intensity was compared before and after each injection. 3. During six experimental sessions, single injections of 1-4 microliters lidocaine near the dorsomedial border of VPM did not significantly alter the monkey's ability to detect small changes in the intensity of noxious heat, cool, airpuff, or visual stimuli despite neurophysiological evidence that spontaneous neuronal activity was blocked within parts of VPM. 4. During three experiments, dual simultaneous microinjections of lidocaine (delivered through 2 microcannulae separated by approximately 1 mm) resulted in profound deficits in noxious heat discrimination, with lesser deficits in cool and airpuff discrimination; visual discrimination was never altered. Monitoring of adjacent microelectrodes revealed that although activity ventral to the injection sites was blocked, activity in medial thalamic nuclei, implicated in nociceptive processing, was probably not altered by these injections. 5. These data suggest that VPM is important for the perception of noxious and innocuous thermal stimuli as well as for the perception of tactile stimuli. However, considering the ineffectiveness of small single microinjections of lidocaine, it appears that some critical proportion of VPM must be inactivated to disrupt

Neurological manifestations and PET studies of the thalamic vascular lesions

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Matsuda, Shinji; Kawamura, Mitsuru; Hirayama, Keizo [Chiba Univ. (Japan). School of Medicine

1995-02-01

We divided 38 patients with cerebrovascular disease of the thalamus into 5 groups according to the site of the thalamic lesions as confirmed by X-ray CT and/or MRI. In 16 patients, we examined the cerebral blood flow (CBF) and cerebral metabolic rate of oxygen (CMRO{sub 2}) by positron emission tomography (PET). In the anteromedial thalamic lesion group, patients displayed disturbances of spontaneity, memory, reading and writing. CBF and CMRO{sub 2} were decreased in the frontal, parietal and temporal lobes on the side of the lesion. In the dorsolateral thalamic lesion group, ataxic hemiparesis was a characteristic symptom. CBF and CMRO{sub 2} were decreased in frontoparietal lobes on the side of the lesion. In the group with lesions confined to the nucleus ventralis posterioris thalami, the main symptoms were sensory disturbance, with cheiro-oral sensory syndrome being particularly evident. CBF and CMRO{sub 2} were decreased in the parietal lobe on the side of the lesion. In the group with posterolateral thalamic lesions without pulvinar involvement, patients exhibited thalamic syndrome without thalamic pain. CBF and CMRO{sub 2} were decreased in the frontoparietal and temporal lobes on the side of the lesion. In contrast, in the group with posterolateral thalamic lesions with pulvinar involvement, all patients showed thalamic pain. The decrease in CBF and CMRO{sub 2} extended to the inferomedial region of the temporal lobe in addition to the area of decreased CBF and CMRO{sub 2} observed in the group with posterolateral thalamic lesions without pulvinar involvement. Based on these results, we speculate that the neurological manifestations of thalamic vascular disease are associated with a decrease in cortical CBF and CMRO{sub 2} secondary to the thalamic lesions. (author).

Variable Action Potential Backpropagation during Tonic Firing and Low-Threshold Spike Bursts in Thalamocortical But Not Thalamic Reticular Nucleus Neurons.

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Connelly, William M; Crunelli, Vincenzo; Errington, Adam C

2017-05-24

Backpropagating action potentials (bAPs) are indispensable in dendritic signaling. Conflicting Ca 2+ -imaging data and an absence of dendritic recording data means that the extent of backpropagation in thalamocortical (TC) and thalamic reticular nucleus (TRN) neurons remains unknown. Because TRN neurons signal electrically through dendrodendritic gap junctions and possibly via chemical dendritic GABAergic synapses, as well as classical axonal GABA release, this lack of knowledge is problematic. To address this issue, we made two-photon targeted patch-clamp recordings from rat TC and TRN neuron dendrites to measure bAPs directly. These recordings reveal that "tonic"' and low-threshold-spike (LTS) "burst" APs in both cell types are always recorded first at the soma before backpropagating into the dendrites while undergoing substantial distance-dependent dendritic amplitude attenuation. In TC neurons, bAP attenuation strength varies according to firing mode. During LTS bursts, somatic AP half-width increases progressively with increasing spike number, allowing late-burst spikes to propagate more efficiently into the dendritic tree compared with spikes occurring at burst onset. Tonic spikes have similar somatic half-widths to late burst spikes and undergo similar dendritic attenuation. In contrast, in TRN neurons, AP properties are unchanged between LTS bursts and tonic firing and, as a result, distance-dependent dendritic attenuation remains consistent across different firing modes. Therefore, unlike LTS-associated global electrical and calcium signals, the spatial influence of bAP signaling in TC and TRN neurons is more restricted, with potentially important behavioral-state-dependent consequences for synaptic integration and plasticity in thalamic neurons. SIGNIFICANCE STATEMENT In most neurons, action potentials (APs) initiate in the axosomatic region and propagate into the dendritic tree to provide a retrograde signal that conveys information about the level of

Strong, reliable and precise synaptic connections between thalamic relay cells and neurones of the nucleus reticularis in juvenile rats

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Gentet, Luc J; Ulrich, Daniel

2003-01-01

The thalamic reticular nucleus (nRT) is composed entirely of GABAergic inhibitory neurones that receive input from pyramidal cortical neurones and excitatory relay cells of the ventrobasal complex of the thalamus (VB). It plays a major role in the synchrony of thalamic networks, yet the synaptic connections it receives from VB cells have never been fully physiologically characterised. Here, whole-cell current-clamp recordings were obtained from 22 synaptically connected VB-nRT cell pairs in slices of juvenile (P14–20) rats. At 34–36 °C, single presynaptic APs evoked unitary EPSPs in nRT cells with a peak amplitude of 7.4 ± 1.5 mV (mean ± s.e.m.) and a decay time constant of 15.1 ± 0.9 ms. Only four out of 22 pairs showed transmission failures at a mean rate of 6.8 ± 1.1 %. An NMDA receptor (NMDAR)-mediated component was significant at rest and subsequent EPSPs in a train were depressed. Only one out of 14 pairs tested was reciprocally connected; the observed IPSPs in the VB cell had a peak amplitude of 0.8 mV and were completely abolished in the presence of 10 μm bicuculline. Thus, synaptic connections from VB cells to nRT neurones are mainly ‘drivers’, while a small subset of cells form closed disynaptic loops. PMID:12563005

Thalamic control of sensory selection in divided attention.

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Wimmer, Ralf D; Schmitt, L Ian; Davidson, Thomas J; Nakajima, Miho; Deisseroth, Karl; Halassa, Michael M

2015-10-29

How the brain selects appropriate sensory inputs and suppresses distractors is unknown. Given the well-established role of the prefrontal cortex (PFC) in executive function, its interactions with sensory cortical areas during attention have been hypothesized to control sensory selection. To test this idea and, more generally, dissect the circuits underlying sensory selection, we developed a cross-modal divided-attention task in mice that allowed genetic access to this cognitive process. By optogenetically perturbing PFC function in a temporally precise window, the ability of mice to select appropriately between conflicting visual and auditory stimuli was diminished. Equivalent sensory thalamocortical manipulations showed that behaviour was causally dependent on PFC interactions with the sensory thalamus, not sensory cortex. Consistent with this notion, we found neurons of the visual thalamic reticular nucleus (visTRN) to exhibit PFC-dependent changes in firing rate predictive of the modality selected. visTRN activity was causal to performance as confirmed by bidirectional optogenetic manipulations of this subnetwork. Using a combination of electrophysiology and intracellular chloride photometry, we demonstrated that visTRN dynamically controls visual thalamic gain through feedforward inhibition. Our experiments introduce a new subcortical model of sensory selection, in which the PFC biases thalamic reticular subnetworks to control thalamic sensory gain, selecting appropriate inputs for further processing.

Disrupted thalamic resting-state functional connectivity in patients with minimal hepatic encephalopathy

International Nuclear Information System (INIS)

Qi, Rongfeng; Zhang, Long Jiang; Zhong, Jianhui; Zhang, Zhiqiang; Ni, Ling; Zheng, Gang; Lu, Guang Ming

2013-01-01

Background and purpose: Little is known about the role of thalamus in the pathophysiology of minimal hepatic encephalopathy (MHE). The purpose of this study was to investigate whether the thalamic functional connectivity was disrupted in cirrhotic patients with MHE by using resting-state functional magnetic resonance imaging (rs-fMRI). Materials and Methods: Twenty seven MHE patients and twenty seven age- and gender- matched healthy controls participated in the rs-fMRI scans. The functional connectivity of 11 thalamic nuclei were characterized by using a standard seed-based whole-brain correlation method and compared between MHE patients and healthy controls. Pearson correlation analysis was performed between the thalamic functional connectivity and venous blood ammonia levels/neuropsychological tests scores of patients. Results: The ventral anterior nucleus (VAN) and the ventral posterior medial nucleus (VPMN) in each side of thalamus showed abnormal functional connectivities in MHE. Compared with healthy controls, MHE patients demonstrated significant decreased functional connectivity between the right/left VAN and the bilateral putamen/pallidum, inferior frontal gyri, insula, supplementary motor area, right middle frontal gyrus, medial frontal gyrus. In addition, MHE patients showed significantly decreased functional connectivity with the right/left VPMN in the bilateral middle temporal gyri (MTG), temporal lobe, and right superior temporal gyrus. The venous blood ammonia levels of MHE patients negatively correlated with the functional connectivity between the VAN and the insula. Number connecting test scores showed negative correlation with the functional connectivity between the VAN and the insula, and between the VPMN and the MTG. Conclusion: MHE patients had disrupted thalamic functional connectivity, which mainly located in the bilateral ventral anterior nuclei and ventral posterior medial nuclei. The decreased connectivity between thalamus and many

Disrupted thalamic resting-state functional connectivity in patients with minimal hepatic encephalopathy

Energy Technology Data Exchange (ETDEWEB)

Qi, Rongfeng [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, Nanjing 210002 (China); Zhang, Long Jiang, E-mail: kevinzhanglongjiang@yahoo.com.cn [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, Nanjing 210002 (China); Zhong, Jianhui [Department of Biomedical Engineering, Zhejiang University, Hangzhou, Zhejiang 310027 (China); Zhang, Zhiqiang; Ni, Ling; Zheng, Gang [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, Nanjing 210002 (China); Lu, Guang Ming, E-mail: cjr.luguangming@vip.163.com [Department of Medical Imaging, Jinling Hospital, Clinical School of Medical College, Nanjing University, Nanjing 210002 (China)

2013-05-15

Background and purpose: Little is known about the role of thalamus in the pathophysiology of minimal hepatic encephalopathy (MHE). The purpose of this study was to investigate whether the thalamic functional connectivity was disrupted in cirrhotic patients with MHE by using resting-state functional magnetic resonance imaging (rs-fMRI). Materials and Methods: Twenty seven MHE patients and twenty seven age- and gender- matched healthy controls participated in the rs-fMRI scans. The functional connectivity of 11 thalamic nuclei were characterized by using a standard seed-based whole-brain correlation method and compared between MHE patients and healthy controls. Pearson correlation analysis was performed between the thalamic functional connectivity and venous blood ammonia levels/neuropsychological tests scores of patients. Results: The ventral anterior nucleus (VAN) and the ventral posterior medial nucleus (VPMN) in each side of thalamus showed abnormal functional connectivities in MHE. Compared with healthy controls, MHE patients demonstrated significant decreased functional connectivity between the right/left VAN and the bilateral putamen/pallidum, inferior frontal gyri, insula, supplementary motor area, right middle frontal gyrus, medial frontal gyrus. In addition, MHE patients showed significantly decreased functional connectivity with the right/left VPMN in the bilateral middle temporal gyri (MTG), temporal lobe, and right superior temporal gyrus. The venous blood ammonia levels of MHE patients negatively correlated with the functional connectivity between the VAN and the insula. Number connecting test scores showed negative correlation with the functional connectivity between the VAN and the insula, and between the VPMN and the MTG. Conclusion: MHE patients had disrupted thalamic functional connectivity, which mainly located in the bilateral ventral anterior nuclei and ventral posterior medial nuclei. The decreased connectivity between thalamus and many

Intralaminar and medial thalamic influence on cortical synchrony, information transmission and cognition

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Yuri B Saalmann

2014-05-01

Full Text Available The intralaminar and medial thalamic nuclei are part of the higher-order thalamus, which receives little sensory input, and instead forms extensive cortico-thalamo-cortical pathways. The large mediodorsal thalamic nucleus predominantly connects with the prefrontal cortex, the adjacent intralaminar nuclei connect with fronto-parietal cortex, and the midline thalamic nuclei connect with medial prefrontal cortex and medial temporal lobe. Taking into account this connectivity pattern, it is not surprising that the intralaminar and medial thalamus has been implicated in a variety of cognitive functions, including memory processing, attention and orienting, as well as reward-based behavior. This review addresses how the intralaminar and medial thalamus may regulate information transmission in cortical circuits. A key neural mechanism may involve intralaminar and medial thalamic neurons modulating the degree of synchrony between different groups of cortical neurons according to behavioral demands. Such a thalamic-mediated synchronization mechanism may give rise to large-scale integration of information across multiple cortical circuits, consequently influencing the level of arousal and consciousness. Overall, the growing evidence supports a general role for the higher-order thalamus in the control of cortical information transmission and cognitive processing.

Prefrontal-Thalamic Anatomical Connectivity and Executive Cognitive Function in Schizophrenia.

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Giraldo-Chica, Monica; Rogers, Baxter P; Damon, Stephen M; Landman, Bennett A; Woodward, Neil D

2018-03-15

Executive cognitive functions, including working memory, cognitive flexibility, and inhibition, are impaired in schizophrenia. Executive functions rely on coordinated information processing between the prefrontal cortex (PFC) and thalamus, particularly the mediodorsal nucleus. This raises the possibility that anatomical connectivity between the PFC and mediodorsal thalamus may be 1) reduced in schizophrenia and 2) related to deficits in executive function. The current investigation tested these hypotheses. Forty-five healthy subjects and 62 patients with a schizophrenia spectrum disorder completed a battery of tests of executive function and underwent diffusion-weighted imaging. Probabilistic tractography was used to quantify anatomical connectivity between six cortical regions, including PFC, and the thalamus. Thalamocortical anatomical connectivity was compared between healthy subjects and patients with schizophrenia using region-of-interest and voxelwise approaches, and the association between PFC-thalamic anatomical connectivity and severity of executive function impairment was examined in patients. Anatomical connectivity between the thalamus and PFC was reduced in schizophrenia. Voxelwise analysis localized the reduction to areas of the mediodorsal thalamus connected to lateral PFC. Reduced PFC-thalamic connectivity in schizophrenia correlated with impaired working memory but not cognitive flexibility and inhibition. In contrast to reduced PFC-thalamic connectivity, thalamic connectivity with somatosensory and occipital cortices was increased in schizophrenia. The results are consistent with models implicating disrupted PFC-thalamic connectivity in the pathophysiology of schizophrenia and mechanisms of cognitive impairment. PFC-thalamic anatomical connectivity may be an important target for procognitive interventions. Further work is needed to determine the implications of increased thalamic connectivity with sensory cortex. Copyright © 2017 Society of

Regional thalamic neuropathology in patients with hippocampal sclerosis and epilepsy: A postmortem study

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Sinjab, Barah; Martinian, Lillian; Sisodiya, Sanjay M; Thom, Maria

2013-01-01

Purpose Clinical, experimental, and neuroimaging data all indicate that the thalamus is involved in the network of changes associated with temporal lobe epilepsy (TLE), particularly in association with hippocampal sclerosis (HS), with potential roles in seizure initiation and propagation. Pathologic changes in the thalamus may be a result of an initial insult, ongoing seizures, or retrograde degeneration through reciprocal connections between thalamic and limbic regions. Our aim was to carry out a neuropathologic analysis of the thalamus in a postmortem (PM) epilepsy series, to assess the distribution, severity, and nature of pathologic changes and its association with HS. Methods Twenty-four epilepsy PM cases (age range 25–87 years) and eight controls (age range 38–85 years) were studied. HS was classified as unilateral (UHS, 11 cases), bilateral (BHS, 4 cases) or absent (No-HS, 9 cases). Samples from the left and right sides of the thalamus were stained with cresyl violet (CV), and for glial firbillary acidic protein (GFAP) and synaptophysin. Using image analysis, neuronal densities (NDs) or field fraction staining values (GFAP, synaptophysin) were measured in four thalamic nuclei: anteroventral nucleus (AV), lateral dorsal nucleus (LD), mediodorsal nucleus (MD), and ventrolateral nucleus (VL). The results were compared within and between cases. Key Findings The severity, nature, and distribution of thalamic pathology varied between cases. A pattern that emerged was a preferential involvement of the MD in UHS cases with a reduction in mean ND ipsilateral to the side of HS (p = 0.05). In UHS cases, greater field fraction values for GFAP and lower values for synaptophysin and ND were seen in the majority of cases in the MD ipsilateral to the side of sclerosis compared to other thalamic nuclei. In addition, differences in the mean ND between classical HS, atypical HS, and No-HS cases were noted in the ipsilateral MD (p < 0.05), with lower values observed in

Sensory processing of deep tissue nociception in the rat spinal cord and thalamic ventrobasal complex.

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Sikandar, Shafaq; West, Steven J; McMahon, Stephen B; Bennett, David L; Dickenson, Anthony H

2017-07-01

Sensory processing of deep somatic tissue constitutes an important component of the nociceptive system, yet associated central processing pathways remain poorly understood. Here, we provide a novel electrophysiological characterization and immunohistochemical analysis of neural activation in the lateral spinal nucleus (LSN). These neurons show evoked activity to deep, but not cutaneous, stimulation. The evoked responses of neurons in the LSN can be sensitized to somatosensory stimulation following intramuscular hypertonic saline, an acute model of muscle pain, suggesting this is an important spinal relay site for the processing of deep tissue nociceptive inputs. Neurons of the thalamic ventrobasal complex (VBC) mediate both cutaneous and deep tissue sensory processing, but in contrast to the lateral spinal nucleus our electrophysiological studies do not suggest the existence of a subgroup of cells that selectively process deep tissue inputs. The sensitization of polymodal and thermospecific VBC neurons to mechanical somatosensory stimulation following acute muscle stimulation with hypertonic saline suggests differential roles of thalamic subpopulations in mediating cutaneous and deep tissue nociception in pathological states. Overall, our studies at both the spinal (lateral spinal nucleus) and supraspinal (thalamic ventrobasal complex) levels suggest a convergence of cutaneous and deep somatosensory inputs onto spinothalamic pathways, which are unmasked by activation of muscle nociceptive afferents to produce consequent phenotypic alterations in spinal and thalamic neural coding of somatosensory stimulation. A better understanding of the sensory pathways involved in deep tissue nociception, as well as the degree of labeled line and convergent pathways for cutaneous and deep somatosensory inputs, is fundamental to developing targeted analgesic therapies for deep pain syndromes. © 2017 University College London. Physiological Reports published by Wiley Periodicals

Gait Balance Disorder by Thalamic Infarction with the Disorder of Interstitial Nucleus of Cajal

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Kurosu, A.; Hayashi, Y.; Wada, K.; Nagaoka, M.

2011-01-01

The interstitial nucleus of Cajal (INC) is thought to play an important role in torsional/vertical eye position and head posture, and disorders of the INC induce abnormal ocular movements and head tilt. Our patients with ocular tilt reactions simultaneously also had disturbances in ambulatory balance, yet no reports address the loss of balance control induced by disorders of the INC. We examined the ambulatory disturbances induced by INC lesion. We experienced three patients with ocular movement disorders and abnormal head tilt due to thalamic infarction. We performed ophthalmic examinations on and checked the balance of them. With funduscopy, abnormal cycloduction was seen in the unaffected side and normal cycloduction was observed in the affected side. Nevertheless, Hess charts showed distortions in the visual image of both eyes. They all had disorders of balance control. We tried to treat them using the Bobath approach for improving their ambulatory balance. With subsequent improvements in balance control it was possible for them to take short walks, but it was difficult to make any improvements in their ocular movement. The INC is related to balance control of ambulation and disorders of the INC induce ambulatory disturbances. Cycloduction was only observed in the unaffected side, but Hess charts showed distortions of the visual image in both eyes. Ambulation was briefly improved, but diplopia persisted in these patients. PMID:21769260

Gait Balance Disorder by Thalamic Infarction with the Disorder of Interstitial Nucleus of Cajal

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A. Kurosu

2011-01-01

Full Text Available The interstitial nucleus of Cajal (INC is thought to play an important role in torsional/vertical eye position and head posture, and disorders of the INC induce abnormal ocular movements and head tilt. Our patients with ocular tilt reactions simultaneously also had disturbances in ambulatory balance, yet no reports address the loss of balance control induced by disorders of the INC. We examined the ambulatory disturbances induced by INC lesion. We experienced three patients with ocular movement disorders and abnormal head tilt due to thalamic infarction. We performed ophthalmic examinations on and checked the balance of them. With funduscopy, abnormal cycloduction was seen in the unaffected side and normal cycloduction was observed in the affected side. Nevertheless, Hess charts showed distortions in the visual image of both eyes. They all had disorders of balance control. We tried to treat them using the Bobath approach for improving their ambulatory balance. With subsequent improvements in balance control it was possible for them to take short walks, but it was difficult to make any improvements in their ocular movement. The INC is related to balance control of ambulation and disorders of the INC induce ambulatory disturbances. Cycloduction was only observed in the unaffected side, but Hess charts showed distortions of the visual image in both eyes. Ambulation was briefly improved, but diplopia persisted in these patients.

Neuronal Correlates of Fear Conditioning in the Bed Nucleus of the Stria Terminalis

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Haufler, Darrell; Nagy, Frank Z.; Pare, Denis

2013-01-01

Lesion and inactivation studies indicate that the central amygdala (CeA) participates in the expression of cued and contextual fear, whereas the bed nucleus of the stria terminalis (BNST) is only involved in the latter. The basis for this functional dissociation is unclear because CeA and BNST form similar connections with the amygdala and…

The pacemaker role of thalamic reticular nucleus in controlling spike-wave discharges and spindles.

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Fan, Denggui; Liao, Fucheng; Wang, Qingyun

2017-07-01

Absence epilepsy, characterized by 2-4 Hz spike-wave discharges (SWDs), can be caused by pathological interactions within the thalamocortical system. Cortical spindling oscillations are also demonstrated to involve the oscillatory thalamocortical rhythms generated by the synaptic circuitry of the thalamus and cortex. This implies that SWDs and spindling oscillations can share the common thalamocortical mechanism. Additionally, the thalamic reticular nucleus (RE) is hypothesized to regulate the onsets and propagations of both the epileptic SWDs and sleep spindles. Based on the proposed single-compartment thalamocortical neural field model, we firstly investigate the stimulation effect of RE on the initiations, terminations, and transitions of SWDs. It is shown that the activations and deactivations of RE triggered by single-pulse stimuli can drive the cortical subsystem to behave as the experimentally observed onsets and self-abatements of SWDs, as well as the transitions from 2-spike and wave discharges (2-SWDs) to SWDs. In particular, with increasing inhibition from RE to the specific relay nucleus (TC), rich transition behaviors in cortex can be obtained through the upstream projection path, RE→TC→Cortex. Although some of the complex dynamical patterns can be expected from the earlier single compartment thalamocortical model, the effect of brain network topology on the emergence of SWDs and spindles, as well as the transitions between them, has not been fully investigated. We thereby develop a spatially extended 3-compartment coupled network model with open-/closed-end connective configurations, to investigate the spatiotemporal effect of RE on the SWDs and spindles. Results show that the degrees of activations of RE 1 can induce the rich spatiotemporal evolution properties including the propagations from SWDs to spindles within different compartments and the transitions between them, through the RE 1 →TC 1 →Cortex 1 and Cortex 1 →Cortex 2 →Cortex 3

The pacemaker role of thalamic reticular nucleus in controlling spike-wave discharges and spindles

Science.gov (United States)

Fan, Denggui; Liao, Fucheng; Wang, Qingyun

2017-07-01

Absence epilepsy, characterized by 2-4 Hz spike-wave discharges (SWDs), can be caused by pathological interactions within the thalamocortical system. Cortical spindling oscillations are also demonstrated to involve the oscillatory thalamocortical rhythms generated by the synaptic circuitry of the thalamus and cortex. This implies that SWDs and spindling oscillations can share the common thalamocortical mechanism. Additionally, the thalamic reticular nucleus (RE) is hypothesized to regulate the onsets and propagations of both the epileptic SWDs and sleep spindles. Based on the proposed single-compartment thalamocortical neural field model, we firstly investigate the stimulation effect of RE on the initiations, terminations, and transitions of SWDs. It is shown that the activations and deactivations of RE triggered by single-pulse stimuli can drive the cortical subsystem to behave as the experimentally observed onsets and self-abatements of SWDs, as well as the transitions from 2-spike and wave discharges (2-SWDs) to SWDs. In particular, with increasing inhibition from RE to the specific relay nucleus (TC), rich transition behaviors in cortex can be obtained through the upstream projection path, RE → TC → Cortex . Although some of the complex dynamical patterns can be expected from the earlier single compartment thalamocortical model, the effect of brain network topology on the emergence of SWDs and spindles, as well as the transitions between them, has not been fully investigated. We thereby develop a spatially extended 3-compartment coupled network model with open-/closed-end connective configurations, to investigate the spatiotemporal effect of RE on the SWDs and spindles. Results show that the degrees of activations of RE 1 can induce the rich spatiotemporal evolution properties including the propagations from SWDs to spindles within different compartments and the transitions between them, through the RE 1 → TC 1 → Cortex 1 and Cortex 1 → Cortex 2 �

Dopamine, fronto-striato-thalamic circuits and risk for psychosis.

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Dandash, Orwa; Pantelis, Christos; Fornito, Alex

2017-02-01

A series of parallel, integrated circuits link distinct regions of prefrontal cortex with specific nuclei of the striatum and thalamus. Dysfunction of these fronto-striato-thalamic systems is thought to play a major role in the pathogenesis of psychosis. In this review, we examine evidence from human and animal investigations that dysfunction of a specific dorsal fronto-striato-thalamic circuit, linking the dorsolateral prefrontal cortex, dorsal (associative) striatum, and mediodorsal nucleus of the thalamus, is apparent across different stages of psychosis, including prior to the onset of a first episode, suggesting that it represents a candidate risk biomarker. We consider how abnormalities at distinct points in the circuit may give rise to the pattern of findings seen in patient populations, and how these changes relate to disruptions in dopamine, glutamate and GABA signaling. Copyright © 2016 Elsevier B.V. All rights reserved.

Schizophrenia; from structure to function with special focus on the mediodorsal thalamic prefrontal loop

DEFF Research Database (Denmark)

Pakkenberg, B.; Scheel-Kruger, J.; Kristiansen, L.V.

2009-01-01

studies in postmortem brain from patients with schizophrenia have reported divergent and often opposing findings in the total number of neurons and volume of the mediodorsal (MD) thalamic nucleus, and to a lesser degree in its reciprocally associated areas of the prefrontal cortex. Similarly, quantitative...

The findings of Tc-99m ECD brain perfusion SPECT in the patients with left anterior thalamic infarction

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Jeong, Y. A.; Kim, S. H.; Sohn, H. S.; Jeong, S. G. [The Catholic University of Korea, Seoul (Korea, Republic of)

2005-07-01

The thalamus has multiple connections with areas of the cerebral cortex involved in arousal and cognition. Thalamic damage has been reported to be associated with variable neuropsychological dysfunctions and dementia. This study evaluates the changes of regional cerebral blood flow (rCBF) by using SPM analysis of brain perfusion SPECT and examining the neuropsychological abnormalities of 4 patients with anterior thalamic infarctions. Four patients with left anterior thalamic infarctions and eleven normal controls were evaluated. K-MMSE and the Seoul Neuropsychological Screening Battery were performed within 2 days after stroke. The normalized SPECT data of 4 patients were compared to those of 11 controls for the detection of areas with decreased rCBF by SPM analysis. All 4 patients showed anterograde amnesia in their verbal memory, which was not improved by recognition. Dysexecutive features were occasionally present, such as decreased word fluency and impaired Stroop test results. SPM analysis revealed decreased rCBF in the left supra marginal gyrus, the superior temporal gyrus, the middle and inferior frontal gyrus, the medial dorsal and anterior nucleus of the left thalamus. The changes of rCBF in patients with left anterior thalamic infarctions may be due to the remote suppression on metabolism by the interruption of the cortico-subcortical circuit, which connects the anterior thalamic nucleus and various cortical areas. The executive dysfunction and dysnomia may be caused by the left dorsolateral frontal dysfunction of the thalamo-cortical circuit. Anterograde amnesia with storage deficit may be caused by the disruption of mamillothalamic tract.

The findings of Tc-99m ECD brain perfusion SPECT in the patients with left anterior thalamic infarction

International Nuclear Information System (INIS)

Jeong, Y. A.; Kim, S. H.; Sohn, H. S.; Jeong, S. G.

2005-01-01

The thalamus has multiple connections with areas of the cerebral cortex involved in arousal and cognition. Thalamic damage has been reported to be associated with variable neuropsychological dysfunctions and dementia. This study evaluates the changes of regional cerebral blood flow (rCBF) by using SPM analysis of brain perfusion SPECT and examining the neuropsychological abnormalities of 4 patients with anterior thalamic infarctions. Four patients with left anterior thalamic infarctions and eleven normal controls were evaluated. K-MMSE and the Seoul Neuropsychological Screening Battery were performed within 2 days after stroke. The normalized SPECT data of 4 patients were compared to those of 11 controls for the detection of areas with decreased rCBF by SPM analysis. All 4 patients showed anterograde amnesia in their verbal memory, which was not improved by recognition. Dysexecutive features were occasionally present, such as decreased word fluency and impaired Stroop test results. SPM analysis revealed decreased rCBF in the left supra marginal gyrus, the superior temporal gyrus, the middle and inferior frontal gyrus, the medial dorsal and anterior nucleus of the left thalamus. The changes of rCBF in patients with left anterior thalamic infarctions may be due to the remote suppression on metabolism by the interruption of the cortico-subcortical circuit, which connects the anterior thalamic nucleus and various cortical areas. The executive dysfunction and dysnomia may be caused by the left dorsolateral frontal dysfunction of the thalamo-cortical circuit. Anterograde amnesia with storage deficit may be caused by the disruption of mamillothalamic tract

Thalamic Ventral Intermediate Nucleus Deep Brain Stimulation for Orthostatic Tremor

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Alexander C. Lehn

2017-07-01

Full Text Available Background: Orthostatic tremor (OT was first described in 1977. It is characterized by rapid tremor of 13–18 Hz and can be recorded in the lower limbs and trunk muscles. OT remains difficult to treat, although some success has been reported with deep brain stimulation (DBS.Case Report: We report a 68-year-old male with OT who did not improve significantly after bilateral thalamic stimulation.Discussion: Although some patients were described who improved after DBS surgery, more information is needed about the effect of these treatment modalities on OT, ideally in the form of randomized trial data. 

Efferent projections of the septum in the Tegu lizard, Tupinambis nigropunctatus.

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Sligar, C M; Voneida, T J

1981-09-01

A H3 proline or H3 leucine mixture was injected into the septal region of the Tegu lizard in order to determine its efferent projections. The brains were processed according to standard autoradiographic technique and counterstained with cresyl violet. Septal projections were limited to either telencephalic or diencephalic areas. Intratelencephalic projections consisted of efferents to medial pallium, nucleus accumbens, bed nucleus of the anterior commissure, preoptic area and septum itself. Fibers entering the diencephalon projected to medial habenular nucleus, dorsomedial thalamic nucleus, dorsolateral thalamic area, periventricular nucleus of the hypothalamus, lateral hypothalamic area and mammillary nucleus. The results are discussed in relation to the efferent projections of the septum in other vertebrates.

Distinct molecular components for thalamic- and cortical-dependent plasticity in the lateral amygdala.

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Mirante, Osvaldo; Brandalise, Federico; Bohacek, Johannes; Mansuy, Isabelle M

2014-01-01

N-methyl-D-aspartate receptor (NMDAR)-dependent long-term depression (LTD) in the lateral nucleus of the amygdala (LA) is a form of synaptic plasticity thought to be a cellular substrate for the extinction of fear memory. The LA receives converging inputs from the sensory thalamus and neocortex that are weakened following fear extinction. Combining field and patch-clamp electrophysiological recordings in mice, we show that paired-pulse low-frequency stimulation can induce a robust LTD at thalamic and cortical inputs to LA, and we identify different underlying molecular components at these pathways. We show that while LTD depends on NMDARs and activation of the protein phosphatases PP2B and PP1 at both pathways, it requires NR2B-containing NMDARs at the thalamic pathway, but NR2C/D-containing NMDARs at the cortical pathway. LTD appears to be induced post-synaptically at the thalamic input but presynaptically at the cortical input, since post-synaptic calcium chelation and NMDAR blockade prevent thalamic but not cortical LTD. These results highlight distinct molecular features of LTD in LA that may be relevant for traumatic memory and its erasure, and for pathologies such as post-traumatic stress disorder (PTSD).

Extrahypothalamic vasopressin and oxytocin in the human brain; presence of vasopressin cells in the bed nucleus of the stria terminalis

NARCIS (Netherlands)

Fliers, E.; Guldenaar, S. E.; van de Wal, N.; Swaab, D. F.

1986-01-01

In the present study, the distribution of extrahypothalamic vasopressin (VP) and oxytocin (OXT) in the human brain was investigated by means of immunocytochemistry. In the septum verum, few VP fibers were found in the nucleus septalis lateralis and medialis (NSL and NSM), and in the bed nucleus of

Neurons in the thalamic reticular nucleus are selective for diverse and complex visual features

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Vishal eVaingankar

2012-12-01

Full Text Available All visual signals the cortex receives are influenced by the perigeniculate sector of the thalamic reticular nucleus, which receives input from relay cells in the lateral geniculate and provides feedback inhibition in return. Relay cells have been studied in quantitative depth; they behave in a roughly linear fashion and have receptive fields with a stereotyped centre-surround structure. We know far less about reticular neurons. Qualitative studies indicate they simply pool ascending input to generate nonselective gain control. Yet the perigeniculate is complicated; local cells are densely interconnected and fire lengthy bursts. Thus, we employed quantitative methods to explore the perigeniculate, using relay cells as controls. By adapting methods of spike-triggered averaging and covariance analysis for bursts, we identified both first and second order features that build reticular receptive fields. The shapes of these spatiotemporal subunits varied widely; no stereotyped pattern emerged. Companion experiments showed that the shape of the first but not second order features could be explained by the overlap of On and Off inputs to a given cell. Moreover, we assessed the predictive power of the receptive field and how much information each component subunit conveyed. Linear-nonlinear models including multiple subunits performed better than those made with just one; further each subunit encoded different visual information. Model performance for reticular cells was always lesser than for relay cells, however, indicating that reticular cells process inputs nonlinearly. All told, our results suggest that the perigeniculate encodes diverse visual features to selectively modulate activity transmitted downstream

Neurons in the thalamic reticular nucleus are selective for diverse and complex visual features

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Vaingankar, Vishal; Soto-Sanchez, Cristina; Wang, Xin; Sommer, Friedrich T.; Hirsch, Judith A.

2012-01-01

All visual signals the cortex receives are influenced by the perigeniculate sector (PGN) of the thalamic reticular nucleus, which receives input from relay cells in the lateral geniculate and provides feedback inhibition in return. Relay cells have been studied in quantitative depth; they behave in a roughly linear fashion and have receptive fields with a stereotyped center-surround structure. We know far less about reticular neurons. Qualitative studies indicate they simply pool ascending input to generate non-selective gain control. Yet the perigeniculate is complicated; local cells are densely interconnected and fire lengthy bursts. Thus, we employed quantitative methods to explore the perigeniculate using relay cells as controls. By adapting methods of spike-triggered averaging and covariance analysis for bursts, we identified both first and second order features that build reticular receptive fields. The shapes of these spatiotemporal subunits varied widely; no stereotyped pattern emerged. Companion experiments showed that the shape of the first but not second order features could be explained by the overlap of On and Off inputs to a given cell. Moreover, we assessed the predictive power of the receptive field and how much information each component subunit conveyed. Linear-non-linear (LN) models including multiple subunits performed better than those made with just one; further each subunit encoded different visual information. Model performance for reticular cells was always lesser than for relay cells, however, indicating that reticular cells process inputs non-linearly. All told, our results suggest that the perigeniculate encodes diverse visual features to selectively modulate activity transmitted downstream. PMID:23269915

Golgi-type I and Golgi-type II neurons in the ventral anterior thalamic nucleus of the adult human: morphological features and quantitative analysis.

Science.gov (United States)

Al-Hussain Bani Hani, Saleh M; El-Dwairi, Qasim A; Bataineh, Ziad M; Al-Haidari, Mohammad S; Al-Alami, Jamil

2008-05-01

The morphological and quantitative features of neurons in the adult human ventral anterior thalamic nucleus were studied in Golgi preparations. Two neuronal types were found and their quantitative features were studied. Golgi-type I neurons were medium to large cells with dense dendritic trees and dendritic protrusions and short hair-like appendages. They have somatic mean diameter of 30.8 microm (+/-9.4, n = 85). They have an average 100.3 dendritic branches, 48.97 dendritic branching points, and 58.85 dendritic tips. The mean diameters of their primary, secondary, and tertiary dendrites were 3.1 microm (+/-1, n = 80), 1.85 microm (+/-0.8, n = 145), and 1.5 microm (+/-0.4, n = 160), respectively. Golgi-type II neurons were small to medium cells with few sparsely branching dendrites and dendritic stalked appendages with or without terminal swellings. They have somatic mean diameters of 22.2 microm (+/-5.8, n = 120). They have an average 33.76 dendritic branches, 16.49 dendritic branching points, and 21.97 dendritic tips. The mean diameters of their primary, secondary, and tertiary dendrites were 1.6 microm (+/-0.86, n = 70), 1.15 microm (+/-0.55, n = 118), and 1 microm (+/-0.70, n = 95), respectively. These quantitative data may form the basis for further quantitative studies involving aging or some degenerative diseases that may affect cell bodies and/or dendritic trees of the Golgi-type I and/or Golgi-type II thalamic neurons.

Distinct molecular components for thalamic- and cortical-dependent plasticity in the lateral amygdala

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Osvaldo eMirante

2014-07-01

Full Text Available N-methyl-D-aspartate receptor (NMDAR-dependent long-term depression (LTD in the lateral nucleus of the amygdala (LA is a form of synaptic plasticity thought to be a cellular substrate for the extinction of fear memory. The LA receives converging inputs from the sensory thalamus and neocortex that are weakened following fear extinction. Combining field and patch-clamp electrophysiological recordings in mice, we show that a paired-pulse low-frequency stimulation can induce a robust LTD at thalamic and cortical inputs to LA, and we identify different underlying molecular components at these pathways. We show that while LTD depends on NMDARs and activation of the protein phosphatases PP2B and PP1 at both pathways, it requires NR2B-containing NMDARs at the thalamic pathway, but NR2C/D-containing NMDARs at the cortical pathway. LTD appears to be induced postsynaptically at the thalamic input but presynaptically at the cortical input, since postsynaptic calcium chelation and NMDAR blockade prevent thalamic but not cortical LTD. These results highlight distinct molecular features of LTD in LA that may be relevant for traumatic memory and its erasure, and for pathologies such as post-traumatic stress disorder (PTSD.

Excitant amino acid projections from rat amygdala and thalamus to nucleus accumbens

International Nuclear Information System (INIS)

Robinson, T.G.; Beart, P.M.

1988-01-01

High affinity uptake of D-[ 3 H]aspartate, [ 3 H]choline and [ 3 H]GABA was examined in synaptosomal-containing preparations of rat nucleus accumbens septi 7 to 10 days after unilateral or bilateral N-methyl-D-aspartate lesions confined to the parataenial nucleus of the thalamus or the basolateral nucleus of the amygdala. Uptake of both D-[ 3 H]aspartate and [ 3 H]choline was significantly reduced (11% and 14% less than control, respectively) by unilateral lesion of the thalamus, whereas [ 3 H]GABA uptake was unaffected. Bilateral thalamic lesions significantly reduced D-[ 3 H]aspartate uptake (11% less than control) into homogenates of the nucleus accumbens, whilst [ 3 H]GABA uptake was unaltered. D-[ 3 H]aspartate uptake was significantly reduced (26% less than control) following unilateral lesion of the amygdala, whereas both [ 3 H]GABA and [ 3 H]choline uptake were unaffected. Bilateral amygdaloid lesions significantly increased D-[ 3 H]aspartate uptake (39% greater than control), whilst uptake of [ 3 H]GABA was not affected. The results implicate glutamate and/or aspartate as putative neurotransmitters in afferent projections from the basolateral amygdala and the parataenial thalamus to the nucleus accumbens. Thalamic afferents to the nucleus accumbens may also utilize acetylcholine as their transmitter

Apoptosis during sexual differentiation of the bed nucleus of the stria terminalis in the rat brain

NARCIS (Netherlands)

Chung, W. C.; Swaab, D. F.; de Vries, G. J. [=Geert J.

2000-01-01

The bed nucleus of the stria terminalis (BST) in the rat forebrain differs between males and females. To test whether apoptosis may contribute to the development of sex differences in the BST, the incidence of apoptosis was determined in sham-treated males and sham-treated females sacrificed on

Subset of Cortical Layer 6b Neurons Selectively Innervates Higher Order Thalamic Nuclei in Mice.

Science.gov (United States)

Hoerder-Suabedissen, Anna; Hayashi, Shuichi; Upton, Louise; Nolan, Zachary; Casas-Torremocha, Diana; Grant, Eleanor; Viswanathan, Sarada; Kanold, Patrick O; Clasca, Francisco; Kim, Yongsoo; Molnár, Zoltán

2018-05-01

The thalamus receives input from 3 distinct cortical layers, but input from only 2 of these has been well characterized. We therefore investigated whether the third input, derived from layer 6b, is more similar to the projections from layer 6a or layer 5. We studied the projections of a restricted population of deep layer 6 cells ("layer 6b cells") taking advantage of the transgenic mouse Tg(Drd1a-cre)FK164Gsat/Mmucd (Drd1a-Cre), that selectively expresses Cre-recombinase in a subpopulation of layer 6b neurons across the entire cortical mantle. At P8, 18% of layer 6b neurons are labeled with Drd1a-Cre::tdTomato in somatosensory cortex (SS), and some co-express known layer 6b markers. Using Cre-dependent viral tracing, we identified topographical projections to higher order thalamic nuclei. VGluT1+ synapses formed by labeled layer 6b projections were found in posterior thalamic nucleus (Po) but not in the (pre)thalamic reticular nucleus (TRN). The lack of TRN collaterals was confirmed with single-cell tracing from SS. Transmission electron microscopy comparison of terminal varicosities from layer 5 and layer 6b axons in Po showed that L6b varicosities are markedly smaller and simpler than the majority from L5. Our results suggest that L6b projections to the thalamus are distinct from both L5 and L6a projections.

The Effect of Thalamic Stimulation on Memory and Language Processing in Parkinsonian Patients

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Zahrasadat Ghoreishi

2006-01-01

Full Text Available Objective: Thalamic Deep Brain Stimulation (DBS is reported to be successful in Parkinson patients with motor symptoms resistant to medication as a treatment procedure. Despite evidence of cortico-subcortico-cortical circuit involvement in motor control, the role of this neural circuitry on higher cognitive functions such as language is still controversial. In particular, research evidence pertaining to the impact of ventrolateral thalamic stimulation on linguistic processing is scarce. This paper investigates the effect of right and left thalamus-DBS on memory and language processing in Parkinson patients. Materials & Methods: In this paper as a case series research we measured memory and language processing in six Parkinson patients (2 left, 2right, 2 bilateral underwent implantation of deep brain stimulating electrode in ventrolateral thalamic nucleus. The data were collected in two “on” and “off” positions, with at least 40 days time interval in between. The patients were assessed using Wechsler memory test, verbal fluency and some sub-tests of Farsi version of Bilingual Aphasia Test (BAT. Results: The findings of this research are suggesting an improvement on grammar comprehension and a decline in sentence production and verbal fluency in “on” position versus “off” position, in both groups. The Wechsler memory scores in left thalamus group improved but declined in right thalamus group. Conclusion: The results indicate that thalamic DBS did not cause any deficit on grammar comprehension and even improved the level of comprehension. On the contrary a decrease in verbal fluency and sentence production, as two high level linguistic processing tasks, was observed. The results confirmed contemporary theories of thalamic participation on language processing and did not confirm a laterality effect on language skills. Although observed difference after thalamic DBS between right and left group on memory score can confirm laterality

Intracellular postsynaptic cannabinoid receptors link thyrotropin-releasing hormone receptors to TRPC-like channels in thalamic paraventricular nucleus neurons.

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Zhang, L; Kolaj, M; Renaud, L P

2015-12-17

In rat thalamic paraventricular nucleus of thalamus (PVT) neurons, activation of thyrotropin-releasing hormone (TRH) receptors enhances excitability via concurrent decrease in G protein-coupled inwardly-rectifying potassium (GIRK)-like and activation of transient receptor potential cation (TRPC)4/5-like cationic conductances. An exploration of intracellular signaling pathways revealed the TRH-induced current to be insensitive to phosphatidylinositol-specific phospholipase C (PI-PLC) inhibitors, but reduced by D609, an inhibitor of phosphatidylcholine-specific PLC (PC-PLC). A corresponding change in the I-V relationship implied suppression of the cationic component of the TRH-induced current. Diacylglycerol (DAG) is a product of the hydrolysis of PC. Studies focused on the isolated cationic component of the TRH-induced response revealed a reduction by RHC80267, an inhibitor of DAG lipase, the enzyme involved in the hydrolysis of DAG to the endocannabinoid 2-arachidonoylglycerol (2-AG). Further investigation revealed enhancement of the cationic component in the presence of either JZL184 or WWL70, inhibitors of enzymes involved in the hydrolysis of 2-AG. A decrease in the TRH-induced response was noted in the presence of rimonabant or SR144528, membrane permeable CB1 and CB2 receptor antagonists, respectively. A decrease in the TRH-induced current by intracellular, but not by bath application of the membrane impermeable peptide hemopressin, selective for CB1 receptors, suggests a postsynaptic intracellular localization of these receptors. The TRH-induced current was increased in the presence of arachidonyl-2'-chloroethylamide (ACEA) or JWH133, CB1 and CB2 receptor agonists, respectively. The PI3-kinase inhibitor LY294002, known to inhibit TRPC translocation, decreased the response to TRH. In addition, a TRH-induced enhancement of the low-threshold spike was prevented by both rimonabant, and SR144528. TRH had no influence on excitatory or inhibitory miniature

Cerebral blood flow and cerebral oxygen metabolism in thalamic hemorrhage

International Nuclear Information System (INIS)

Yasui, Nobuyuki; Asakura, Ken

1987-01-01

Cerebral blood flow (CBF), cerebral oxygen consumption (CMRO 2 ), oxygen extraction fraction (OEF) and cerebral blood volume (CBV) were studied in 20 cases of thalamic hemorrhage using positron CT and 15 O labeled gas steady-state inhalation method. CBF reduction was limited around the thalamus in the small sized hematoma. CBF were significantly diminished in the mean cortical, parietal, temporal, basal ganglia and thalamic area ipsilateral and cerebellar cortex contralateral to the medium sized hematoma. There was bilateral and diffuse CBF reduction in the large sized hematoma which was caused by increased intracranial pressure. CMRO 2 value were similary changed as CBF. OEF change showed within normal limit. Diffuse CBV reduction was observed in the large sized hematoma. This reduction was the result of decreased vascular bed caused by mass effect of the hematoma and hydrocephalus. Effect of surgical treatment such as ventricular drainage and hematoma evacuation were also discussed in correlation to CBF in some case using positron and single photon ECT. (author)

High field FMRI reveals thalamocortical integration of segregated cognitive and emotional processing in mediodorsal and intralaminar thalamic nuclei.

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Metzger, C D; Eckert, U; Steiner, J; Sartorius, A; Buchmann, J E; Stadler, J; Tempelmann, C; Speck, O; Bogerts, B; Abler, B; Walter, M

2010-01-01

Thalamocortical loops, connecting functionally segregated, higher order cortical regions, and basal ganglia, have been proposed not only for well described motor and sensory regions, but also for limbic and prefrontal areas relevant for affective and cognitive processes. These functions are, however, more specific to humans, rendering most invasive neuroanatomical approaches impossible and interspecies translations difficult. In contrast, non-invasive imaging of functional neuroanatomy using fMRI allows for the development of elaborate task paradigms capable of testing the specific functionalities proposed for these circuits. Until recently, spatial resolution largely limited the anatomical definition of functional clusters at the level of distinct thalamic nuclei. Since their anatomical distinction seems crucial not only for the segregation of cognitive and limbic loops but also for the detection of their functional interaction during cognitive-emotional integration, we applied high resolution fMRI on 7 Tesla. Using an event-related design, we could isolate thalamic effects for preceding attention as well as experience of erotic stimuli. We could demonstrate specific thalamic effects of general emotional arousal in mediodorsal nucleus and effects specific to preceding attention and expectancy in intralaminar centromedian/parafascicular complex. These thalamic effects were paralleled by specific coactivations in the head of caudate nucleus as well as segregated portions of rostral or caudal cingulate cortex and anterior insula supporting distinct thalamo-striato-cortical loops. In addition to predescribed effects of sexual arousal in hypothalamus and ventral striatum, high resolution fMRI could extent this network to paraventricular thalamus encompassing laterodorsal and parataenial nuclei. We could lend evidence to segregated subcortical loops which integrate cognitive and emotional aspects of basic human behavior such as sexual processing.

Altered thalamic functional connectivity in multiple sclerosis

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Liu, Yaou; Liang, Peipeng; Duan, Yunyun; Huang, Jing; Ren, Zhuoqiong; Jia, Xiuqin [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Dong, Huiqing; Ye, Jing [Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China); Shi, Fu-Dong [Department of Neurology and Tianjin Neurological Institute, Tianjin Medical University General Hospital, Tianjin 300052 (China); Butzkueven, Helmut [Department of Medicine, University of Melbourne, Parkville 3010 (Australia); Li, Kuncheng, E-mail: kunchengli55@gmail.com [Department of Radiology, Xuanwu Hospital, Capital Medical University, Beijing 100053 (China)

2015-04-15

Highlights: •We demonstrated decreased connectivity between thalamus and cortical regions in MS. •Increased intra- and inter-thalamic connectivity was also observed in MS. •The increased functional connectivity is attenuated by increasing disease duration. -- Abstract: Objective: To compare thalamic functional connectivity (FC) in patients with multiple sclerosis (MS) and healthy controls (HC), and correlate these connectivity measures with other MRI and clinical variables. Methods: We employed resting-state functional MRI (fMRI) to examine changes in thalamic connectivity by comparing thirty-five patients with MS and 35 age- and sex-matched HC. Thalamic FC was investigated by correlating low frequency fMRI signal fluctuations in thalamic voxels with voxels in all other brain regions. Additionally thalamic volume fraction (TF), T2 lesion volume (T2LV), EDSS and disease duration were recorded and correlated with the FC changes. Results: MS patients were found to have a significantly lower TF than HC in bilateral thalami. Compared to HC, the MS group showed significantly decreased FC between thalamus and several brain regions including right middle frontal and parahippocampal gyri, and the left inferior parietal lobule. Increased intra- and inter-thalamic FC was observed in the MS group compared to HC. These FC alterations were not correlated with T2LV, thalamic volume or lesions. In the MS group, however, there was a negative correlation between disease duration and inter-thalamic connectivity (r = −0.59, p < 0.001). Conclusion: We demonstrated decreased FC between thalamus and several cortical regions, while increased intra- and inter-thalamic connectivity in MS patients. These complex functional changes reflect impairments and/or adaptations that are independent of T2LV, thalamic volume or presence of thalamic lesions. The negative correlation between disease duration and inter-thalamic connectivity could indicate an adaptive role of thalamus that is

Hypertensive thalamic hemorrhage

International Nuclear Information System (INIS)

Munaka, Masahiro; Nishikawa, Michio; Hirai, Osamu; Kaneko, Takaaki; Watanabe, Syu; Fukuma, Jun; Handa, Hajime

1988-01-01

In the past six years, we have had experience with 40 patients with hypertensive thalamic hemorrhages, as verified by CT scan at our hospital within 24 hours. These patients were classified into the following three groups according to the location of the bleeding point and the size of the hematoma: (1) anteromedial (4 cases), (2) posterolateral (16 cases), and (3) massive (20 cases). The (1) and (2) hematomas were small (less than 3 cm in diameter), while those in (3) were large (more than 3 cm in diameter). Twenty cases (50% of all the thalamic hematomas) were small hematomas. The characteristic clinical symptoms of the anteromedial type were a mild disturbance of consciousness and thalamic dementia, while those of the posterolateral type were motor and sensory disturbance, and thalamic aphasia, respectively. Twenty cases (50%) were large hematomas. The clinical symptoms of these cases were mainly consciousness disturbance; 7 of them expired. Based on this experience, it may be considered that the patients whose hematoma size was larger than 3 cm had a poor prognosis and that the patients with the posterolateral type had a poor functional diagnosis. (author)

Opposite roles for neuropeptide S in the nucleus accumbens and bed nucleus of the stria terminalis in learned helplessness rats.

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Shirayama, Yukihiko; Ishima, Tamaki; Oda, Yasunori; Okamura, Naoe; Iyo, Masaomi; Hashimoto, Kenji

2015-09-15

The role of neuropeptide S (NPS) in depression remains unclear. We examined the antidepressant-like effects of NPS infusions into the shell or core regions of the nucleus accumbens (NAc) and into the bed nucleus of the stria terminalis (BNST) of learned helplessness (LH) rats (an animal model of depression). Infusions of NPS (10 pmol/side) into the NAc shell, but not the NAc core and BNST, exerted antidepressant-like effects in the LH paradigm. Implying that behavioral deficits could be improved in the conditioned avoidance test. Coinfusion of SHA68 (an NPS receptor antagonist, 100 pmol/side) with NPS into the NAc shell blocked these effects. In contrast, NPS receptor antagonism by SHA68 in the BNST induced antidepressant-like effects. Infusions of NPS into the NAc shell or SHA68 into the BNST did not produce memory deficits or locomotor activation in the passive avoidance and open field tests. These results suggest that excitatory and inhibitory actions by the NPS system are integral to the depression in LH animals. Copyright © 2015 Elsevier B.V. All rights reserved.

High Field fMRI Reveals Thalamocortical Integration of Segregated Cognitive and Emotional Processing in Mediodorsal and Intralaminar Thalamic Nuclei

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Metzger, C. D.; Eckert, U.; Steiner, J.; Sartorius, A.; Buchmann, J. E.; Stadler, J.; Tempelmann, C.; Speck, O.; Bogerts, B.; Abler, B.; Walter, M.

2010-01-01

Thalamocortical loops, connecting functionally segregated, higher order cortical regions, and basal ganglia, have been proposed not only for well described motor and sensory regions, but also for limbic and prefrontal areas relevant for affective and cognitive processes. These functions are, however, more specific to humans, rendering most invasive neuroanatomical approaches impossible and interspecies translations difficult. In contrast, non-invasive imaging of functional neuroanatomy using fMRI allows for the development of elaborate task paradigms capable of testing the specific functionalities proposed for these circuits. Until recently, spatial resolution largely limited the anatomical definition of functional clusters at the level of distinct thalamic nuclei. Since their anatomical distinction seems crucial not only for the segregation of cognitive and limbic loops but also for the detection of their functional interaction during cognitive–emotional integration, we applied high resolution fMRI on 7 Tesla. Using an event-related design, we could isolate thalamic effects for preceding attention as well as experience of erotic stimuli. We could demonstrate specific thalamic effects of general emotional arousal in mediodorsal nucleus and effects specific to preceding attention and expectancy in intralaminar centromedian/parafascicular complex. These thalamic effects were paralleled by specific coactivations in the head of caudate nucleus as well as segregated portions of rostral or caudal cingulate cortex and anterior insula supporting distinct thalamo–striato–cortical loops. In addition to predescribed effects of sexual arousal in hypothalamus and ventral striatum, high resolution fMRI could extent this network to paraventricular thalamus encompassing laterodorsal and parataenial nuclei. We could lend evidence to segregated subcortical loops which integrate cognitive and emotional aspects of basic human behavior such as sexual processing. PMID:21088699

High field fMRI reveals thalamocortical integration of segregated cognitive and emotional processing in mediodorsal and intralaminar thalamic nuclei

Directory of Open Access Journals (Sweden)

Coraline Danielle Metzger

2010-11-01

Full Text Available Thalamocortical loops, connecting functionally segregated, higher order cortical regions and basal ganglia, have been proposed not only for well described motor and sensory regions, but also for limbic and prefrontal areas relevant for affective and cognitive processes. These functions are, however, more specific to humans, rendering most invasive neuroanatomical approaches impossible and interspecies translations difficult. In contrast, non invasive imaging of functional neuroanatomy using fMRI allows for the development of elaborate task paradigms capable of testing the specific functionalities proposed for these circuits. Until recently, spatial resolution largely limited the anatomical definition of functional clusters at the level of distinct thalamic nuclei. Since their anatomical distinction seems crucial not only for the segregation of cognitive and limbic loops but also for the detection of their functional interaction during cognitive-emotional integration, we applied high resolution fMRI on 7 Tesla.Using an event related design, we could isolate thalamic effects for preceding attention as well as experience of erotic stimuli. We could demonstrate specific thalamic effects of general emotional arousal in mediodorsal nucleus and effects specific to preceding attention and expectancy in intralaminar centromedian/parafascicular complex (CM/PF. These thalamic effects were paralleled by specific coactivations in the head of caudate nucleus as well as segregated portions of rostral or caudal cingulate cortex and anterior insula supporting distinct thalamo-striato-cortical loops. In addition to predescribed effects of sexual arousal in hypothalamus and ventral striatum, high resolution fMRI could extent this network to paraventricular thalamus encompassing laterodorsal and parataenial nuclei. We could lend evidence to segregated subcortical loops which integrate cognitive and emotional aspects of basic human behaviour such as sexual

Dissociable Contributions of Thalamic Nuclei to Recognition Memory: Novel Evidence from a Case of Medial Dorsal Thalamic Damage

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Newsome, Rachel N.; Trelle, Alexandra N.; Fidalgo, Celia; Hong, Bryan; Smith, Victoria M.; Jacob, Alexander; Ryan, Jennifer D.; Rosenbaum, R. Shayna; Cowell, Rosemary A.; Barense, Morgan D.

2018-01-01

The thalamic nuclei are thought to play a critical role in recognition memory. Specifically, the anterior thalamic nuclei and medial dorsal nuclei may serve as critical output structures in distinct hippocampal and perirhinal cortex systems, respectively. Existing evidence indicates that damage to the anterior thalamic nuclei leads to impairments…

Unilateral Thalamic Infarct Presenting as a Convulsive Seizure.

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Kumar, Rajesh; Brohi, Hazim; Mughul, Afshan

2017-09-01

Lesions of the thalamus and those extending into midbrain can cause various types of movement disorders such as dystonia, asterixis and ballism-chorea. Seizures are rare manifestation of thalamic disorder. Occurrence of seizures in bilateral thalamic infarct has been reported; but seizures in unilateral thalamic infarct have been reported very rarely. Literature review showed only single case of perinatal unilateral thalamic infarct presenting with seizures. We are reporting a unique case of convulsive seizure at the onset of unilateral thalamic infarct in an adult male, which has never been reported to the best of our knowledge.

Neuronal responses to tactile stimuli and tactile sensations evoked by microstimulation in the human thalamic principal somatic sensory nucleus (ventral caudal).

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Schmid, Anne-Christine; Chien, Jui-Hong; Greenspan, Joel D; Garonzik, Ira; Weiss, Nirit; Ohara, Shinji; Lenz, Frederick Arthur

2016-06-01

The normal organization and plasticity of the cutaneous core of the thalamic principal somatosensory nucleus (ventral caudal, Vc) have been studied by single-neuron recordings and microstimulation in patients undergoing awake stereotactic operations for essential tremor (ET) without apparent somatic sensory abnormality and in patients with dystonia or chronic pain secondary to major nervous system injury. In patients with ET, most Vc neurons responded to one of the four stimuli, each of which optimally activates one mechanoreceptor type. Sensations evoked by microstimulation were similar to those evoked by the optimal stimulus only among rapidly adapting neurons. In patients with ET, Vc was highly segmented somatotopically, and vibration, movement, pressure, and sharp sensations were usually evoked by microstimulation at separate sites in Vc. In patients with conditions including spinal cord transection, amputation, or dystonia, RFs were mismatched with projected fields more commonly than in patients with ET. The representation of the border of the anesthetic area (e.g., stump) or of the dystonic limb was much larger than that of the same part of the body in patients with ET. This review describes the organization and reorganization of human Vc neuronal activity in nervous system injury and dystonia and then proposes basic mechanisms. Copyright © 2016 the American Physiological Society.

MM2-thalamic Creutzfeldt-Jakob disease: neuropathological, biochemical and transmission studies identify a distinctive prion strain.

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Moda, Fabio; Suardi, Silvia; Di Fede, Giuseppe; Indaco, Antonio; Limido, Lucia; Vimercati, Chiara; Ruggerone, Margherita; Campagnani, Ilaria; Langeveld, Jan; Terruzzi, Alessandro; Brambilla, Antonio; Zerbi, Pietro; Fociani, Paolo; Bishop, Matthew T; Will, Robert G; Manson, Jean C; Giaccone, Giorgio; Tagliavini, Fabrizio

2012-09-01

In Creutzfeldt-Jakob disease (CJD), molecular typing based on the size of the protease resistant core of the disease-associated prion protein (PrP(Sc) ) and the M/V polymorphism at codon 129 of the PRNP gene correlates with the clinico-pathologic subtypes. Approximately 95% of the sporadic 129MM CJD patients are characterized by cerebral deposition of type 1 PrP(Sc) and correspond to the classic clinical CJD phenotype. The rare 129MM CJD patients with type 2 PrP(Sc) are further subdivided in a cortical and a thalamic form also indicated as sporadic fatal insomnia. We observed two young patients with MM2-thalamic CJD. Main neuropathological features were diffuse, synaptic PrP immunoreactivity in the cerebral cortex and severe neuronal loss and gliosis in the thalamus and olivary nucleus. Western blot analysis showed the presence of type 2A PrP(Sc) . Challenge of transgenic mice expressing 129MM human PrP showed that MM2-thalamic sporadic CJD (sCJD) was able to transmit the disease, at variance with MM2-cortical sCJD. The affected mice showed deposition of type 2A PrP(Sc) , a scenario that is unprecedented in this mouse line. These data indicate that MM2-thalamic sCJD is caused by a prion strain distinct from the other sCJD subtypes including the MM2-cortical form. © 2012 The Authors; Brain Pathology © 2012 International Society of Neuropathology.

Enlarged thalamic volumes and increased fractional anisotropy in the thalamic radiations in Veterans with suicide behaviors

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Melissa eLopez-Larson

2013-08-01

Full Text Available Post-mortem studies have suggested a link between the thalamus, psychiatric disorders, and suicide. We evaluated the thalamus and anterior thalamic radiations (ATR in a group of Veterans with and without a history of suicidal behavior (SB to determine if thalamic abnormalities were associated with an increased risk of SB. Forty Veterans with mild traumatic brain injury (TBI and no SB (TBI-SB, 19 Veterans with mild TBI and a history of SB (TB+SB and 15 healthy controls (HC underwent MRI scanning including a structural and diffusion tensor imaging scan. Suicidal behaviors were evaluated utilizing the Columbia Suicide Rating Scale and impulsivity was measured using the Barratt Impulsiveness Scale (BIS. Differences in thalamic volumes and ATR fractional anisotropy (FA were examined between 1 TBI+SB versus HC and 2 TBI+SB versus combined HC and TBI-SB and 2 between TBI+SB and TBI-SB. Left and right thalamic volumes were significantly increased in those with TBI+SB compared to the HC, TBI-SB and the combined group. Veterans with TBI+SB had increased FA bilaterally compared to the HC, HC and TBI-SB group, and the TBI-SB only group. Significant positive associations were found for bilateral ATR and BIS in the TBI+SB group. Our findings of thalamic enlargement and increased FA in individuals with TBI+SB suggest that this region may be a biomarker for suicide risk. Our findings are consistent with previous evidence indicating that suicide may be associated with behavioral disinhibition and frontal-thalamic-limbic dysfunction and suggest a neurobiologic mechanism that may increase vulnerability to suicide.

The role of the thalamic nuclei in recognition memory accompanied by recall during encoding and retrieval: an fMRI study.

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Pergola, Giulio; Ranft, Alexander; Mathias, Klaus; Suchan, Boris

2013-07-01

The present functional imaging study aimed at investigating the contribution of the mediodorsal nucleus and the anterior nuclei of the thalamus with their related cortical networks to recognition memory and recall. Eighteen subjects performed associative picture encoding followed by a single item recognition test during the functional magnetic resonance imaging session. After scanning, subjects performed a cued recall test using the formerly recognized pictures as cues. This post-scanning test served to classify recognition trials according to subsequent recall performance. In general, single item recognition accompanied by successful recall of the associations elicited stronger activation in the mediodorsal nucleus of the thalamus and in the prefrontal cortices both during encoding and retrieval compared to recognition without recall. In contrast, the anterior nuclei of the thalamus were selectively active during the retrieval phase of recognition followed by recall. A correlational analysis showed that activation of the anterior thalamus during retrieval as assessed by measuring the percent signal changes predicted lower rates of recognition without recall. These findings show that the thalamus is critical for recognition accompanied by recall, and provide the first evidence of a functional segregation of the thalamic nuclei with respect to the memory retrieval phase. In particular, the mediodorsal thalamic-prefrontal cortical network is activated during successful encoding and retrieval of associations, which suggests a role of this system in recall and recollection. The activity of the anterior thalamic-temporal network selectively during retrieval predicts better memory performances across subjects and this confirms the paramount role of this network in recall and recollection. Copyright © 2013 Elsevier Inc. All rights reserved.

Visual discrimination in the pigeon (Columba livia): effects of selective lesions of the nucleus rotundus

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Laverghetta, A. V.; Shimizu, T.

1999-01-01

The nucleus rotundus is a large thalamic nucleus in birds and plays a critical role in many visual discrimination tasks. In order to test the hypothesis that there are functionally distinct subdivisions in the nucleus rotundus, effects of selective lesions of the nucleus were studied in pigeons. The birds were trained to discriminate between different types of stationary objects and between different directions of moving objects. Multiple regression analyses revealed that lesions in the anterior, but not posterior, division caused deficits in discrimination of small stationary stimuli. Lesions in neither the anterior nor posterior divisions predicted effects in discrimination of moving stimuli. These results are consistent with a prediction led from the hypothesis that the nucleus is composed of functional subdivisions.

A computational relationship between thalamic sensory neural responses and contrast perception.

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Jiang, Yaoguang; Purushothaman, Gopathy; Casagrande, Vivien A

2015-01-01

Uncovering the relationship between sensory neural responses and perceptual decisions remains a fundamental problem in neuroscience. Decades of experimental and modeling work in the sensory cortex have demonstrated that a perceptual decision pool is usually composed of tens to hundreds of neurons, the responses of which are significantly correlated not only with each other, but also with the behavioral choices of an animal. Few studies, however, have measured neural activity in the sensory thalamus of awake, behaving animals. Therefore, it remains unclear how many thalamic neurons are recruited and how the information from these neurons is pooled at subsequent cortical stages to form a perceptual decision. In a previous study we measured neural activity in the macaque lateral geniculate nucleus (LGN) during a two alternative forced choice (2AFC) contrast detection task, and found that single LGN neurons were significantly correlated with the monkeys' behavioral choices, despite their relatively poor contrast sensitivity and a lack of overall interneuronal correlations. We have now computationally tested a number of specific hypotheses relating these measured LGN neural responses to the contrast detection behavior of the animals. We modeled the perceptual decisions with different numbers of neurons and using a variety of pooling/readout strategies, and found that the most successful model consisted of about 50-200 LGN neurons, with individual neurons weighted differentially according to their signal-to-noise ratios (quantified as d-primes). These results supported the hypothesis that in contrast detection the perceptual decision pool consists of multiple thalamic neurons, and that the response fluctuations in these neurons can influence contrast perception, with the more sensitive thalamic neurons likely to exert a greater influence.

The effect of unilateral thalamic deep brain stimulation on the vocal dysfunction in a patient with spasmodic dysphonia: interrogating cerebellar and pallidal neural circuits.

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Poologaindran, Anujan; Ivanishvili, Zurab; Morrison, Murray D; Rammage, Linda A; Sandhu, Mini K; Polyhronopoulos, Nancy E; Honey, Christopher R

2018-02-01

Spasmodic dysphonia (SD) is a neurological disorder of the voice where a patient's ability to speak is compromised due to involuntary contractions of the intrinsic laryngeal muscles. Since the 1980s, SD has been treated with botulinum toxin A (BTX) injections into the throat. This therapy is limited by the delayed-onset of benefits, wearing-off effects, and repeated injections required every 3 months. In a patient with essential tremor (ET) and coincident SD, the authors set out to quantify the effects of thalamic deep brain stimulation (DBS) on vocal function while investigating the underlying motor thalamic circuitry. A 79-year-old right-handed woman with ET and coincident adductor SD was referred to our neurosurgical team. While primarily treating her limb tremor, the authors studied the effects of unilateral, thalamic DBS on vocal function using the Unified Spasmodic Dysphonia Rating Scale (USDRS) and voice-related quality of life (VRQOL). Since dystonia is increasingly being considered a multinodal network disorder, an anterior trajectory into the left thalamus was deliberately chosen such that the proximal contacts of the electrode were in the ventral oralis anterior (Voa) nucleus (pallidal outflow) and the distal contacts were in the ventral intermediate (Vim) nucleus (cerebellar outflow). In addition to assessing on/off unilateral thalamic Vim stimulation on voice, the authors experimentally assessed low-voltage unilateral Vim, Voa, or multitarget stimulation in a prospective, randomized, doubled-blinded manner. The evaluators were experienced at rating SD and were familiar with the vocal tremor of ET. A Wilcoxon signed-rank test was used to study the pre- and posttreatment effect of DBS on voice. Unilateral left thalamic Vim stimulation (DBS on) significantly improved SD vocal dysfunction compared with no stimulation (DBS off), as measured by the USDRS (p dysphonia. A Phase 1 pilot trial (DEBUSSY; clinical trial no. NCT02558634, clinicaltrials.gov) is

Prefrontal cortex-projecting glutamatergic thalamic paraventricular nucleus-excited by hypocretin: a feedforward circuit that may enhance cognitive arousal.

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Huang, Hao; Ghosh, Prabhat; van den Pol, Anthony N

2006-03-01

The paraventricular thalamic nucleus (PVT) receives one of the most dense innervations by hypothalamic hypocretin/orexin (Hcrt) neurons, which play important roles in sleep-wakefulness, attention, and autonomic function. The PVT projects to several loci, including the medial prefrontal cortex (mPFC), a cortical region involved in associative function and attention. To study the effect of Hcrt on excitatory PVT neurons that project to the mPFC, we used a new line of transgenic mice expressing green fluorescent protein (GFP) under the control of the vesicular glutamate-transporter-2 promoter. These neurons were retrogradely labeled with cholera toxin subunit B that had been microinjected into the mPFC. Membrane characteristics and responses to hypocretin-1 and -2 (Hcrt-1 and -2) were studied using whole cell recording (n > 300). PVT neurons showed distinct membrane properties including inward rectification, H-type potassium currents, low threshold spikes, and spike frequency adaptation. Cortically projecting neurons were depolarized and excited by Hcrt-2. Hcrt-2 actions were stronger than those of Hcrt-1, and the action persisted in TTX and in low calcium/high magnesium artificial cerebrospinal fluid, consistent with direct actions mediated by Hcrt receptor-2. Two mechanisms of Hcrt excitation were found: an increase in input resistance caused by closure of potassium channels and activation of nonselective cation channels. The robust excitation evoked by Hcrt-2 on cortically projecting glutamate PVT neurons could generate substantial excitation in multiple layers of the mPFC, adding to the more selective direct excitatory actions of Hcrt in the mPFC and potentially increasing cortical arousal and attention to limbic or visceral states.

At the centre of neuronal, synaptic and axonal pathology in murine prion disease: degeneration of neuroanatomically linked thalamic and brainstem nuclei

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Reis, Renata; Hennessy, Edel; Murray, Caoimhe; Griffin, Éadaoin W.

2015-01-01

Aims The processes by which neurons degenerate in chronic neurodegenerative diseases remain unclear. Synaptic loss and axonal pathology frequently precede neuronal loss and protein aggregation demonstrably spreads along neuroanatomical pathways in many neurodegenerative diseases. The spread of neuronal pathology is less studied. Methods We previously demonstrated severe neurodegeneration in the posterior thalamus of multiple prion disease strains. Here we used the ME7 model of prion disease to examine the nature of this degeneration in the posterior thalamus and the major brainstem projections into this region. Results We objectively quantified neurological decline between 16 and 18 weeks post‐inoculation and observed thalamic subregion‐selective neuronal, synaptic and axonal pathology while demonstrating relatively uniform protease‐resistant prion protein (PrP) aggregation and microgliosis across the posterior thalamus. Novel amyloid precursor protein (APP) pathology was particularly prominent in the thalamic posterior (PO) and ventroposterior lateral (VPL) nuclei. The brainstem nuclei forming the major projections to these thalamic nuclei were examined. Massive neuronal loss in the PO was not matched by significant neuronal loss in the interpolaris (Sp5I), while massive synaptic loss in the ventral posteromedial nucleus (VPM) did correspond with significant neuronal loss in the principal trigeminal nucleus. Likewise, significant VPL synaptic loss was matched by significant neuronal loss in the gracile and cuneate nuclei. Conclusion These findings demonstrate significant spread of neuronal pathology from the thalamus to the brainstem in prion disease. The divergent neuropathological features in adjacent neuronal populations demonstrates that there are discrete pathways to neurodegeneration in different neuronal populations. PMID:25727649

Feedforward inhibitory control of sensory information in higher-order thalamic nuclei.

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Lavallée, Philippe; Urbain, Nadia; Dufresne, Caroline; Bokor, Hajnalka; Acsády, László; Deschênes, Martin

2005-08-17

Sensory stimuli evoke strong responses in thalamic relay cells, which ensure a faithful relay of information to the neocortex. However, relay cells of the posterior thalamic nuclear group in rodents, despite receiving significant trigeminal input, respond poorly to vibrissa deflection. Here we show that sensory transmission in this nucleus is impeded by fast feedforward inhibition mediated by GABAergic neurons of the zona incerta. Intracellular recordings of posterior group neurons revealed that the first synaptic event after whisker deflection is a prominent inhibition. Whisker-evoked EPSPs with fast rise time and longer onset latency are unveiled only after lesioning the zona incerta. Excitation survives barrel cortex lesion, demonstrating its peripheral origin. Electron microscopic data confirm that trigeminal axons make large synaptic terminals on the proximal dendrites of posterior group cells and on the somata of incertal neurons. Thus, the connectivity of the system allows an unusual situation in which inhibition precedes ascending excitation resulting in efficient shunting of the responses. The dominance of inhibition over excitation strongly suggests that the paralemniscal pathway is not designed to relay inputs triggered by passive whisker deflection. Instead, we propose that this pathway operates through disinhibition, and that the posterior group forwards to the cerebral cortex sensory information that is contingent on motor instructions.

Generation of thalamic neurons from mouse embryonic stem cells.

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Shiraishi, Atsushi; Muguruma, Keiko; Sasai, Yoshiki

2017-04-01

The thalamus is a diencephalic structure that plays crucial roles in relaying and modulating sensory and motor information to the neocortex. The thalamus develops in the dorsal part of the neural tube at the level of the caudal forebrain. However, the molecular mechanisms that are essential for thalamic differentiation are still unknown. Here, we have succeeded in generating thalamic neurons from mouse embryonic stem cells (mESCs) by modifying the default method that induces the most-anterior neural type in self-organizing culture. A low concentration of the caudalizing factor insulin and a MAPK/ERK kinase inhibitor enhanced the expression of the caudal forebrain markers Otx2 and Pax6. BMP7 promoted an increase in thalamic precursors such as Tcf7l2 + /Gbx2 + and Tcf7l2 + /Olig3 + cells. mESC thalamic precursors began to express the glutamate transporter vGlut2 and the axon-specific marker VGF, similar to mature projection neurons. The mESC thalamic neurons extended their axons to cortical layers in both organotypic culture and subcortical transplantation. Thus, we have identified the minimum elements sufficient for in vitro generation of thalamic neurons. These findings expand our knowledge of thalamic development. © 2017. Published by The Company of Biologists Ltd.

Role of the thalamic nucleus reuniens in mediating interactions between the hippocampus and medial prefrontal cortex during spatial working memory

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Amy L Griffin

2015-03-01

Full Text Available Despite decades of research, the neural mechanisms of spatial working memory remain poorly understood. Although the dorsal hippocampus is known to be critical for memory-guided behavior, experimental evidence suggests that spatial working memory depends not only on the hippocampus itself, but also on the circuit comprised of the hippocampus and the medial prefrontal cortex (mPFC. Disruption of hippocampal-mPFC interactions may result in failed transfer of spatial and contextual information processed by the hippocampus to the circuitry in mPFC responsible for decision making and goal-directed behavior. Oscillatory synchrony between the hippocampus and mPFC has been shown to increase in tasks with high spatial working memory demand. However, the mechanisms and circuitry supporting hippocampal-mPFC interactions during these tasks is unknown. The midline thalamic nucleus reuniens (RE is reciprocally connected to both the hippocampus and the mPFC and has been shown to be critical for a variety of working memory tasks. Therefore, it is likely that hippocampal-mPFC oscillatory synchrony is modulated by RE activity. This article will review the anatomical connections between the hippocampus, mPFC and RE along with the behavioral studies that have investigated the effects of RE disruption on working memory task performance. The article will conclude with suggestions for future directions aimed at identifying the specific role of the RE in regulating functional interactions between the hippocampus and the PFC and investigating the degree to which these interactions contribute to spatial working memory.

Pathogenesis and prognosis of bilateral thalamic infarction

International Nuclear Information System (INIS)

Nakase, Taizen; Ogura, Naoko; Maeda, Tetsuya; Yamazaki, Takashi; Kameda, Tomoaki; Sato, Yuichi; Nagata, Ken

2008-01-01

Only a few reports have discussed the detailed clinical symptoms and pathogenesis of bilateral thalamic infarction. The thalamus is composed of different functional nuclei and supplied by vessels containing several variations from the main arteries, leading to difficulty in the precise evaluation of bilateral thalamic infarction. In the present study, we assessed the prognosis of bilateral thalamic infarction based on the distribution of stroke lesions. From among the consecutive ischemic stroke patients admitted to hospital between April 2001 and March 2005, cases of acute bilateral thalamic infarction were selected for this study (n=9; 65.1±13.6 y.o.). The stroke lesions and vascular abnormalities were investigated by magnetic resonance imaging and magnetic resonance angiography on admission. Outcome was evaluated from the modified Rankin scale (mRS) at discharge. Good outcome patients (mRS 0-2; n=5) showed memory disturbance, cognitive impairment and hypersomnia. On the other hand, quadriplegia, oculomotor disturbance and bulbar palsy were observed in the poor outcome patients (mRS≥4; n=4). The critical features of a poor outcome were the age at onset (72.0±15.3 vs. 58.2±11.9 y.o.), inclusion of brainstem lesions and total occlusion of the basilar artery. In conclusion, older age at onset and/or basilar artery occlusion may be critical factors for predicting a poor outcome in bilateral thalamic infarction cases. (author)

Development-dependent behavioral change toward pups and synaptic transmission in the rhomboid nucleus of the bed nucleus of the stria terminalis.

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Amano, Taiju; Shindo, Sayaka; Yoshihara, Chihiro; Tsuneoka, Yousuke; Uki, Haruka; Minami, Masabumi; Kuroda, Kumi O

2017-05-15

Sexually naïve male C57BL/6 mice aggressively bite unfamiliar pups. This behavior, called infanticide, is considered an adaptive reproductive strategy of males of polygamous species. We recently found that the rhomboid nucleus of the bed nucleus of the stria terminalis (BSTrh) is activated during infanticide and that the bilateral excitotoxic lesions of BSTrh suppress infanticidal behavior. Here we show that 3-week-old male C57BL/6 mice rarely engaged in infanticide and instead, provided parental care toward unfamiliar pups, consistent with observations in rats and other rodent species. This inhibition of infanticide at the periweaning period is functional because the next litter will be born at approximately the time of weaning of the previous litter through maternal postpartum ovulation. However, the mechanism of this age-dependent behavioral change is unknown. Therefore, we performed whole-cell patch clamp recordings of BSTrh and compared evoked neurotransmission in response to the stimulation of the stria terminalis of adult and 3-week-old male mice. Although we were unable to detect a significant difference in the amplitudes of inhibitory neurotransmission, the amplitudes and the paired-pulse ratio of evoked excitatory postsynaptic currents differed between adult and 3-week-old mice. These data suggest that maturation of the synaptic terminal in BSTrh that occurred later than 3 weeks after birth may mediate by the adaptive change from parental to infanticidal behavior in male mice. Copyright © 2016 Elsevier B.V. All rights reserved.

The calcium-binding protein parvalbumin modulates the firing 1 properties of the reticular thalamic nucleus bursting neurons.

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Albéri, Lavinia; Lintas, Alessandra; Kretz, Robert; Schwaller, Beat; Villa, Alessandro E P

2013-06-01

The reticular thalamic nucleus (RTN) of the mouse is characterized by an overwhelming majority of GABAergic neurons receiving afferences from both the thalamus and the cerebral cortex and sending projections mainly on thalamocortical neurons. The RTN neurons express high levels of the "slow Ca(2+) buffer" parvalbumin (PV) and are characterized by low-threshold Ca(2+) currents, I(T). We performed extracellular recordings in ketamine/xylazine anesthetized mice in the rostromedial portion of the RTN. In the RTN of wild-type and PV knockout (PVKO) mice we distinguished four types of neurons characterized on the basis of their firing pattern: irregular firing (type I), medium bursting (type II), long bursting (type III), and tonically firing (type IV). Compared with wild-type mice, we observed in the PVKOs the medium bursting (type II) more frequently than the long bursting type and longer interspike intervals within the burst without affecting the number of spikes. This suggests that PV may affect the firing properties of RTN neurons via a mechanism associated with the kinetics of burst discharges. Ca(v)3.2 channels, which mediate the I(T) currents, were more localized to the somatic plasma membrane of RTN neurons in PVKO mice, whereas Ca(v)3.3 expression was similar in both genotypes. The immunoelectron microscopy analysis showed that Ca(v)3.2 channels were localized at active axosomatic synapses, thus suggesting that the differential localization of Ca(v)3.2 in the PVKOs may affect bursting dynamics. Cross-correlation analysis of simultaneously recorded neurons from the same electrode tip showed that about one-third of the cell pairs tended to fire synchronously in both genotypes, independent of PV expression. In summary, PV deficiency does not affect the functional connectivity between RTN neurons but affects the distribution of Ca(v)3.2 channels and the dynamics of burst discharges of RTN cells, which in turn regulate the activity in the thalamocortical circuit.

The Emotional Gatekeeper: A Computational Model of Attentional Selection and Suppression through the Pathway from the Amygdala to the Inhibitory Thalamic Reticular Nucleus.

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Yohan J John

2016-02-01

Full Text Available In a complex environment that contains both opportunities and threats, it is important for an organism to flexibly direct attention based on current events and prior plans. The amygdala, the hub of the brain's emotional system, is involved in forming and signaling affective associations between stimuli and their consequences. The inhibitory thalamic reticular nucleus (TRN is a hub of the attentional system that gates thalamo-cortical signaling. In the primate brain, a recently discovered pathway from the amygdala sends robust projections to TRN. Here we used computational modeling to demonstrate how the amygdala-TRN pathway, embedded in a wider neural circuit, can mediate selective attention guided by emotions. Our Emotional Gatekeeper model demonstrates how this circuit enables focused top-down, and flexible bottom-up, allocation of attention. The model suggests that the amygdala-TRN projection can serve as a unique mechanism for emotion-guided selection of signals sent to cortex for further processing. This inhibitory selection mechanism can mediate a powerful affective 'framing' effect that may lead to biased decision-making in highly charged emotional situations. The model also supports the idea that the amygdala can serve as a relevance detection system. Further, the model demonstrates how abnormal top-down drive and dysregulated local inhibition in the amygdala and in the cortex can contribute to the attentional symptoms that accompany several neuropsychiatric disorders.

The Emotional Gatekeeper: A Computational Model of Attentional Selection and Suppression through the Pathway from the Amygdala to the Inhibitory Thalamic Reticular Nucleus

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Bullock, Daniel; Barbas, Helen

2016-01-01

In a complex environment that contains both opportunities and threats, it is important for an organism to flexibly direct attention based on current events and prior plans. The amygdala, the hub of the brain's emotional system, is involved in forming and signaling affective associations between stimuli and their consequences. The inhibitory thalamic reticular nucleus (TRN) is a hub of the attentional system that gates thalamo-cortical signaling. In the primate brain, a recently discovered pathway from the amygdala sends robust projections to TRN. Here we used computational modeling to demonstrate how the amygdala-TRN pathway, embedded in a wider neural circuit, can mediate selective attention guided by emotions. Our Emotional Gatekeeper model demonstrates how this circuit enables focused top-down, and flexible bottom-up, allocation of attention. The model suggests that the amygdala-TRN projection can serve as a unique mechanism for emotion-guided selection of signals sent to cortex for further processing. This inhibitory selection mechanism can mediate a powerful affective ‘framing’ effect that may lead to biased decision-making in highly charged emotional situations. The model also supports the idea that the amygdala can serve as a relevance detection system. Further, the model demonstrates how abnormal top-down drive and dysregulated local inhibition in the amygdala and in the cortex can contribute to the attentional symptoms that accompany several neuropsychiatric disorders. PMID:26828203

Intraoperative neurophysiological responses in epileptic patients submitted to hippocampal and thalamic deep brain stimulation.

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Cukiert, Arthur; Cukiert, Cristine Mella; Argentoni-Baldochi, Meire; Baise, Carla; Forster, Cássio Roberto; Mello, Valeria Antakli; Burattini, José Augusto; Lima, Alessandra Moura

2011-12-01

Deep brain stimulation (DBS) has been used in an increasing frequency for treatment of refractory epilepsy. Acute deep brain macrostimulation intraoperative findings were sparsely published in the literature. We report on our intraoperative macrostimulation findings during thalamic and hippocampal DBS implantation. Eighteen patients were studied. All patients underwent routine pre-operative evaluation that included clinical history, neurological examination, interictal and ictal EEG, high resolution 1.5T MRI and neuropsychological testing. Six patients with temporal lobe epilepsy were submitted to hippocampal DBS (Hip-DBS); 6 patients with focal epilepsy were submitted to anterior thalamic nucleus DBS (AN-DBS) and 6 patients with generalized epilepsy were submitted to centro-median thalamic nucleus DBS (CM-DBS). Age ranged from 9 to 40 years (11 males). All patients were submitted to bilateral quadripolar DBS electrode implantation in a single procedure, under general anesthesia, and intraoperative scalp EEG monitoring. Final electrode's position was checked postoperatively using volumetric CT scanning. Bipolar stimulation using the more proximal and distal electrodes was performed. Final standard stimulation parameters were 6Hz, 4V, 300μs (low frequency range: LF) or 130Hz, 4V, 300μs (high frequency range: HF). Bilateral recruiting response (RR) was obtained after unilateral stimulation in all patients submitted to AN and CM-DBS using LF stimulation. RR was widespread but prevailed over the fronto-temporal region bilaterally, and over the stimulated hemisphere. HF stimulation led to background slowing and a DC shift. The mean voltage for the appearance of RR was 4V (CM) and 3V (AN). CM and AN-DBS did not alter inter-ictal spiking frequency or morphology. RR obtained after LF Hip-DBS was restricted to the stimulated temporal lobe and no contralateral activation was noted. HF stimulation yielded no visually recognizable EEG modification. Mean intensity for initial

Thalamic changes with mesial temporal sclerosis: MRI

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Deasy, N.P.; Jarosz, J.M.; Cox, T.C.S. [Department of Neuroradiology, King' s College Hospital, London (United Kingdom); Elwes, R.C.D. [Department of Neurology, King' s College Hospital, London (United Kingdom); Polkey, C.E. [Department of Neurosurgery, King' s College and Maudsley Hospitals, London (United Kingdom)

2000-05-01

We reviewed the preoperative images of 28 patients with pathologically proven mesial temporal sclerosis, to assess thalamic asymmetry and signal change. A further 25 nonsurgical patients with temporal lobe epilepsy and unequivocal, unilateral changes of mesial temporal sclerosis, and 20 controls, were also reviewed. None of the control group had unequivocal asymmetry of the thalamus. There was an ipsilateral asymmetrically small thalamus in five (18 %) of the surgical group and in three (12 %) of the nonsurgical patients. In four cases there was thalamic signal change. In three patients with thalamic volume loss there was ipsilateral hemiatrophy. All patients with an asymmetrically small thalamus had an asymmetrically small fornix and all but one a small ipsilateral mamillary body. (orig.)

Remote effect in patients with thalamic stroke. A study using positron emission tomography

International Nuclear Information System (INIS)

Komaba, Yuichi; Kitamura, Shin; Terashi, Akiro

1998-01-01

The purpose of this study was to investigate the functional relation between the thalamus and other cortical regions in patients with thalamic stroke from the view of cerebral blood flow (CBF) and the cerebral metabolic rate of oxygen (CMRO 2 ) using positron emission tomography (PET). Twenty patients with thalamic stroke (right lesion=8, left lesion=12) and 7 normal controls were studied. Five patients were diagnosed as having thalamic infarction, and 15 (patients were diagnosed) as having thalamic hemorrhage by X-CT and/or MRI scan. Regional cerebral blood flow and cerebral metabolic rate of oxygen were measured by PET using C 15 O 2 and 15 O 2 steady state inhalation technique. In the left thalamic stroke group, CMRO 2 was significantly decreased in the left cingulate, superior frontal, superior temporal, middle temporal, medial occipital, and thalamic regions, compared with the normal control group. In the right thalamic stroke group, CMRO 2 was decreased in the left cingulate, medial occipital, right hippocampal, thalamic, and the bilateral cerebellar regions, compared with the normal control group. In the left thalamic stroke group, CBF was decreased significantly in the left cingulate, middle temporal, hippocampal, thalamic, and right cerebellar regions, compared with the normal control group. In the right thalamic stroke group, CBF was significantly decreased in the right hippocampal, thalamic and left cerebellar regions compared with the normal control group. These results indicate that CBF and CMRO 2 decrease in some distant regions from thalamic lesions, perhaps due to a disconnection of neuronal fiber. Especially in the left thalamic stroke group, CMRO 2 was decreased in the ipsilateral temporal regions. This result suggests that there are more intimate functional fiber connections between the thalamus and temporal cortex in the left hemisphere than in the right hemisphere. (author)

Visual Orientation and Directional Selectivity through Thalamic Synchrony

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Stanley, Garrett B.; Jin, Jianzhong; Wang, Yushi; Desbordes, Gaëlle; Wang, Qi; Black, Michael J.; Alonso, Jose-Manuel

2012-01-01

Thalamic neurons respond to visual scenes by generating synchronous spike trains on the timescale of 10 – 20 ms that are very effective at driving cortical targets. Here we demonstrate that this synchronous activity contains unexpectedly rich information about fundamental properties of visual stimuli. We report that the occurrence of synchronous firing of cat thalamic cells with highly overlapping receptive fields is strongly sensitive to the orientation and the direction of motion of the visual stimulus. We show that this stimulus selectivity is robust, remaining relatively unchanged under different contrasts and temporal frequencies (stimulus velocities). A computational analysis based on an integrate-and-fire model of the direct thalamic input to a layer 4 cortical cell reveals a strong correlation between the degree of thalamic synchrony and the nonlinear relationship between cortical membrane potential and the resultant firing rate. Together, these findings suggest a novel population code in the synchronous firing of neurons in the early visual pathway that could serve as the substrate for establishing cortical representations of the visual scene. PMID:22745507

Amygdala and bed nucleus of the stria terminalis circuitry: Implications for addiction-related behaviors.

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Stamatakis, Alice M; Sparta, Dennis R; Jennings, Joshua H; McElligott, Zoe A; Decot, Heather; Stuber, Garret D

2014-01-01

Complex motivated behavioral processes, such as those that can go awry following substance abuse and other neuropsychiatric disorders, are mediated by a distributive network of neurons that reside throughout the brain. Neural circuits within the amygdala regions, such as the basolateral amygdala (BLA), and downstream targets such as the bed nucleus of the stria terminalis (BNST), are critical neuroanatomical structures for orchestrating emotional behavioral responses that may influence motivated actions such as the reinstatement of drug seeking behavior. Here, we review the functional neurocircuitry of the BLA and the BNST, and discuss how these circuits may guide maladaptive behavioral processes such as those seen in addiction. Thus, further study of the functional connectivity within these brain regions and others may provide insight for the development of new treatment strategies for substance use disorders. This article is part of a Special Issue entitled 'NIDA 40th Anniversary Issue'. Copyright © 2013 Elsevier Ltd. All rights reserved.

Right thalamic infarction after closed head injury

International Nuclear Information System (INIS)

Nagaya, Takashi; Doi, Terushige; Katsumata, Tsuguo; Kuwayama, Naoto

1986-01-01

We reported a case of right thalamic infarction after a closed head injury. A 12-year-old boy was hit by an autotruck. He was semi-comatose, with left temporal scalp swelling and excoriation in the left lower limb. Three days after the accident, he exhibited left hemiparesis. CT scans on the day of the accident showed no abnormality, but on the following day, right thalamic infarction appeared. Right carotid angiography showed only an irregular vascular shadow in the cisternal segment of the right internal carotid artery. Vascular obstruction after closed head injury is rare, especially in the intracranial vessels, and several pathogeneses may be postulated. The right thalamic infarction in this case was supposed to be due to the damage of the perforators from the right posterior communicating artery and the right posterior cerebral artery, which were struck as a contre-coup by the force from the left side. (author)

Hypertensive thalamic hematoma treated by CT stereotactic evacuation (with two cases reports)

International Nuclear Information System (INIS)

Wang Hongsheng; Zhu Fengqing

2002-01-01

Objective: To investigate new surgical method to treat hypertensive thalamic hematoma. Methods: Two medial-degree coma patients with hypertensive thalamic hematoma were treated by CT stereotactic evacuation. Results: One week after operation the two patients regained consciousness. The function of paraplegic appendage restored partly, and one patient could take care of himself. Conclusion: CT stereotactic evacuation to treat hypertensive thalamic hematoma has the advantages of small trauma, little complication and good clinical results. The authors suggest that it be selected firstly in treating hypertensive thalamic hematoma

Emerging Role for Corticotropin Releasing Factor Signaling in the Bed Nucleus of the Stria Terminalis at the Intersection of Stress and Reward

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Silberman, Yuval; Winder, Danny G.

2013-01-01

Stress and anxiety play an important role in the development and maintenance of drug and alcohol addiction. The bed nucleus of the stria terminalis (BNST), a brain region involved in the production of long-term stress-related behaviors, plays an important role in animal models of relapse, such as reinstatement to previously extinguished drug-seeking behaviors. While a number of neurotransmitter systems have been suggested to play a role in these behaviors, recent evidence points to the neurop...

Response sensitivity of barrel neuron subpopulations to simulated thalamic input.

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Pesavento, Michael J; Rittenhouse, Cynthia D; Pinto, David J

2010-06-01

Our goal is to examine the relationship between neuron- and network-level processing in the context of a well-studied cortical function, the processing of thalamic input by whisker-barrel circuits in rodent neocortex. Here we focus on neuron-level processing and investigate the responses of excitatory and inhibitory barrel neurons to simulated thalamic inputs applied using the dynamic clamp method in brain slices. Simulated inputs are modeled after real thalamic inputs recorded in vivo in response to brief whisker deflections. Our results suggest that inhibitory neurons require more input to reach firing threshold, but then fire earlier, with less variability, and respond to a broader range of inputs than do excitatory neurons. Differences in the responses of barrel neuron subtypes depend on their intrinsic membrane properties. Neurons with a low input resistance require more input to reach threshold but then fire earlier than neurons with a higher input resistance, regardless of the neuron's classification. Our results also suggest that the response properties of excitatory versus inhibitory barrel neurons are consistent with the response sensitivities of the ensemble barrel network. The short response latency of inhibitory neurons may serve to suppress ensemble barrel responses to asynchronous thalamic input. Correspondingly, whereas neurons acting as part of the barrel circuit in vivo are highly selective for temporally correlated thalamic input, excitatory barrel neurons acting alone in vitro are less so. These data suggest that network-level processing of thalamic input in barrel cortex depends on neuron-level processing of the same input by excitatory and inhibitory barrel neurons.

Anterior Thalamic High Frequency Band Activity Is Coupled with Theta Oscillations at Rest

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Catherine M. Sweeney-Reed

2017-07-01

Full Text Available Cross-frequency coupling (CFC between slow and fast brain rhythms, in the form of phase–amplitude coupling (PAC, is proposed to enable the coordination of neural oscillatory activity required for cognitive processing. PAC has been identified in the neocortex and mesial temporal regions, varying according to the cognitive task being performed and also at rest. PAC has also been observed in the anterior thalamic nucleus (ATN during memory processing. The thalamus is active during the resting state and has been proposed to be involved in switching between task-free cognitive states such as rest, in which attention is internally-focused, and externally-focused cognitive states, in which an individual engages with environmental stimuli. It is unknown whether PAC is an ongoing phenomenon during the resting state in the ATN, which is modulated during different cognitive states, or whether it only arises during the performance of specific tasks. We analyzed electrophysiological recordings of ATN activity during rest from seven patients who received thalamic electrodes implanted for treatment of pharmacoresistant focal epilepsy. PAC was identified between theta (4–6 Hz phase and high frequency band (80–150 Hz amplitude during rest in all seven patients, which diminished during engagement in tasks involving an external focus of attention. The findings are consistent with the proposal that theta–gamma coupling in the ATN is an ongoing phenomenon, which is modulated by task performance.

Sub-threshold cross-modal sensory interaction in the thalamus: lemniscal auditory response in the medial geniculate nucleus is modulated by somatosensory stimulation.

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Donishi, T; Kimura, A; Imbe, H; Yokoi, I; Kaneoke, Y

2011-02-03

Recent studies have highlighted cross-modal sensory modulations in the primary sensory areas in the cortex, suggesting that cross-modal sensory interactions occur at early stages in the hierarchy of sensory processing. Multi-modal sensory inputs from non-lemniscal thalamic nuclei and cortical inputs from the secondary sensory and association areas are considered responsible for the modulations. On the other hand, there is little evidence of cross-sensory modal sensitivities in lemniscal thalamic nuclei. In the present study, we were interested in a possibility that somatosensory stimulation may affect auditory response in the ventral division (MGV) of the medial geniculate nucleus (MG), a lemniscal thalamic nucleus that is considered to be dedicated to auditory uni-modal processing. Experiments were performed on anesthetized rats. Transcutaneous electrical stimulation of the hindpaw, which is thought to evoke nociception and seems unrelated to auditory processing, modulated unit discharges in response to auditory stimulation (noise bursts). The modulation was observed in the MGV and non-lemniscal auditory thalamic nuclei such as the dorsal and medial divisions of the MG. The major effect of somatosensory stimulation was suppression. The most robust suppression was induced by electrical stimuli given simultaneously with noise bursts or preceding noise bursts by 10 to 20 ms. The results indicate that the lemniscal (MGV) and non-lemniscal auditory nuclei are subject to somatosensory influence. In everyday experience intense somatosensory stimuli such as pain interrupt our ongoing hearing or interfere with clear recognition of sound. The modulation of lemniscal auditory response by somatosensory stimulation may underlie such cross-modal disturbance of auditory perception as a form of cross-modal switching of attention. Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.

Unified thalamic model generates multiple distinct oscillations with state-dependent entrainment by stimulation.

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Guoshi Li

2017-10-01

Full Text Available The thalamus plays a critical role in the genesis of thalamocortical oscillations, yet the underlying mechanisms remain elusive. To understand whether the isolated thalamus can generate multiple distinct oscillations, we developed a biophysical thalamic model to test the hypothesis that generation of and transition between distinct thalamic oscillations can be explained as a function of neuromodulation by acetylcholine (ACh and norepinephrine (NE and afferent synaptic excitation. Indeed, the model exhibited four distinct thalamic rhythms (delta, sleep spindle, alpha and gamma oscillations that span the physiological states corresponding to different arousal levels from deep sleep to focused attention. Our simulation results indicate that generation of these distinct thalamic oscillations is a result of both intrinsic oscillatory cellular properties and specific network connectivity patterns. We then systematically varied the ACh/NE and input levels to generate a complete map of the different oscillatory states and their transitions. Lastly, we applied periodic stimulation to the thalamic network and found that entrainment of thalamic oscillations is highly state-dependent. Our results support the hypothesis that ACh/NE modulation and afferent excitation define thalamic oscillatory states and their response to brain stimulation. Our model proposes a broader and more central role of the thalamus in the genesis of multiple distinct thalamo-cortical rhythms than previously assumed.

[Deficit of verbal recall caused by left dorso-lateral thalamic infarction].

Science.gov (United States)

Rousseaux, M; Cabaret, M; Benaim, C; Steinling, M

1995-01-01

A case of amnesia with preferential disorder of verbal recall, associated to a limited infarct of the left superior, external and anterior thalamus, is reported. This lesion involved the anterior and middle dorso-lateral nuclei and the centrolateral nucleus, sparing most of the structures classically incriminated in diencephalic amnesia. At the initial stage, the patient presented discrete language impairment and severe deficit of semantic processing, which later recovered. At the late stage, the anterograde and retrograde amnesia principally concerned the recall of verbal information used in daily life, verbal learning using short-term and long-term recall, questionnaires evaluating retrograde memory and requiring the evocation of proper names. Verbal priming was also affected. Verbal recognition was preserved. Evocation of the most recent events of the personal life was also impaired. Confrontation of this case with others previously reported suggests that various thalamic amnesias may be described, associated to different cognitive deficits, in relation with the preferential situation of lesions.

Communication skills and thalamic lesion: Strategies of rehabilitation.

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Amaddii, Luisa; Centorrino, Santi; Cambi, Jacopo; Passali, Desiderio

2014-01-01

To describe the speech rehabilitation history of patients with thalamic lesions. Thalamic lesions can affect speech and language according to diverse thalamic nuclei involved. Because of the strategic functional position of the thalamus within the cognitive networks, its lesion can also interfere with other cognitive processes, such as attention, memory and executive functions. Alterations of these cognitive domains contribute significantly to language deficits, leading to communicative inefficacy. This fact must be considered in the rehabilitation efforts. Whereas evaluation of cognitive functions and communicative efficiency is different from that of aphasic disorder, treatment should also be different. The treatment must be focused on specific cognitive deficits with belief in the regaining of communicative ability, as well as it occurs in therapy of pragmatic disorder in traumatic brain injury: attention process training, mnemotechnics and prospective memory training. According to our experience: (a) there is a close correlation between cognitive processes and communication skills; (b) alterations of attention, memory and executive functions cause a loss of efficiency in the language use; and (c) appropriate cognitive treatment improves pragmatic competence and therefore the linguistic disorder. For planning a speech-therapy it is important to consider the relationship between cognitive functions and communication. The cognitive/behavioral treatment confirms its therapeutic efficiency for thalamic lesions. Copyright © 2014 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

Thalamic diffusion differences related to cognitive function in white matter lesions.

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Fernández-Andújar, Marina; Soriano-Raya, Juan José; Miralbell, Júlia; López-Cancio, Elena; Cáceres, Cynthia; Bargalló, Núria; Barrios, Maite; Arenillas, Juan Francisco; Toran, Pere; Alzamora, Maite; Clemente, Imma; Dávalos, Antoni; Mataró, Maria

2014-05-01

Cerebral white matter lesions (WMLs) are related to cognitive deficits, probably due to a disruption of frontal-subcortical circuits. We explored thalamic diffusion differences related to white matter lesions (WMLs) and their association with cognitive function in middle-aged individuals. Ninety-six participants from the Barcelona-AsIA Neuropsychology Study were included. Participants were classified into groups based on low grade and high grade of periventricular hyperintensities (PVHs) and deep white matter hyperintensities (DWMHs). Tract-Based Spatial Statistics was used to study thalamic diffusion differences between groups. Mean fractional anisotropy (FA) values in significant areas were calculated for each subject and correlated with cognitive performance. Participants with high-grade PVHs and DWMHs showed lower FA thalamic values compared to those with low-grade PVHs and DWMHs, respectively. Decreased FA thalamic values in high-grade DWMHs, but not high-grade PVH, were related to lower levels of performance in psychomotor speed, verbal fluency, and visuospatial skills. Thalamic diffusion differences are related to lower cognitive function only in participants with high-grade DWMHs. These results support the hypothesis that fronto-subcortical disruption is associated with cognitive function only in DWMHs. Copyright © 2014 Elsevier Inc. All rights reserved.

Thalamic gap junctions control local neuronal synchrony and influence macroscopic oscillation amplitude during EEG alpha rhythms

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Stuart eHughes

2011-08-01

Full Text Available Although EEG alpha ( (8-13 Hz rhythms are often considered to reflect an ‘idling’ brain state, numerous studies indicate that they are also related to many aspects of perception. Recently, we outlined a potential cellular substrate by which such aspects of perception might be linked to basic  rhythm mechanisms. This scheme relies on a specialized subset of rhythmically bursting thalamocortical (TC neurons (high-threshold bursting cells in the lateral geniculate nucleus (LGN which are interconnected by gap junctions (GJs. By engaging GABAergic interneurons, that in turn inhibit conventional relay-mode TC neurons, these cells can lead to an effective temporal framing of thalamic relay-mode output. Although the role of GJs is pivotal in this scheme, evidence for their involvement in thalamic  rhythms has thus far mainly derived from experiments in in vitro slice preparations. In addition, direct anatomical evidence of neuronal GJs in the LGN is currently lacking. To address the first of these issues we tested the effects of the GJ inhibitors, carbenoxolone (CBX and 18-glycyrrhetinic acid (18-GA, given directly to the LGN via reverse microdialysis, on spontaneous LGN and EEG  rhythms in behaving cats. We also examined the effect of CBX on  rhythm-related LGN unit activity. Indicative of a role for thalamic GJs in these activities, 18-GA and CBX reversibly suppressed both LGN and EEG  rhythms, with CBX also decreasing neuronal synchrony. To address the second point, we used electron microscopy to obtain definitive ultrastructural evidence for the presence of GJs between neurons in the cat LGN. As interneurons show no phenotypic evidence of GJ coupling (i.e. dye-coupling and spikelets we conclude that these GJs must belong to TC neurons. The potential significance of these findings for relating macroscopic changes in  rhythms to basic cellular processes is discussed.

A unique combination of anatomy and physiology in cells of the rat paralaminar thalamic nuclei adjacent to the medial geniculate body

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Smith, Philip H.; Bartlett, Edward L.; Kowalkowski, Anna

2010-01-01

The medial geniculate body (MGB) has three major subdivisions - ventral (MGV), dorsal (MGD) and medial (MGM). MGM is linked with paralaminar nuclei that are situated medial and ventral to MGV/MGD. Paralaminar nuclei have unique inputs and outputs when compared with MGV and MGD and have been linked to circuitry underlying some important functional roles. We recorded intracellularly from cells in the paralaminar nuclei in vitro. We found that they possess an unusual combination of anatomical and physiological features when compared to those reported for “standard” thalamic neurons seen in the MGV/MGD and elsewhere in the thalamus. Compared to MGV/MGD neurons, anatomically, 1) paralaminar cell dendrites can be long, branch sparingly and encompass a much larger area. 2) their dendrites may be smooth but can have well defined spines and 3) their axons can have collaterals that branch locally within the same or nearby paralaminar nuclei. When compared to MGV/MGD neurons physiologically 1) their spikes are larger in amplitude and can be shorter in duration and 2) can have dual afterhyperpolarizations with fast and slow components and 3) they can have a reduction or complete absence of the low threshold, voltage-sensitive calcium conductance that reduces or eliminates the voltage-dependent burst response. We also recorded from cells in the parafascicular nucleus, a nucleus of the posterior intralaminar nuclear group, because they have unusual anatomical features that are similar to some of our paralaminar cells. Like the labeled paralaminar cells, parafascicular cells had physiological features distinguishing them from typical thalamic neurons. PMID:16566009

Outcome After Pituitary Radiosurgery for Thalamic Pain Syndrome

International Nuclear Information System (INIS)

Hayashi, Motohiro; Chernov, Mikhail F.; Taira, Takaomi; Ochiai, Taku; Nakaya, Kotaro; Tamura, Noriko; Goto, Shinichi; Yomo, Shoji; Kouyama, Nobuo; Katayama, Yoko; Kawakami, Yoriko; Izawa, Masahiro; Muragaki, Yoshihiro

2007-01-01

Purpose: To evaluate outcomes after pituitary radiosurgery in patients with post-stroke thalamic pain syndrome. Methods and Materials: From 2002 to 2006, 24 patients with thalamic pain syndrome underwent pituitary radiosurgery at Tokyo Women's Medical University and were followed at least 12 months thereafter. The radiosurgical target was defined as the pituitary gland and its connection with the pituitary stalk. The maximum dose varied from 140 to 180 Gy. Mean follow-up after treatment was 35 months (range, 12-48 months). Results: Initial pain reduction, usually within 48 h after radiosurgery, was marked in 17 patients (71%). However, in the majority of cases the pain recurred within 6 months after treatment, and at the time of the last follow-up examination durable pain control was marked in only 5 patients (21%). Ten patients (42%) had treatment-associated side effects. Anterior pituitary abnormalities were marked in 8 cases and required hormonal replacement therapy in 3; transient diabetes insipidus was observed in 2 cases, transient hyponatremia in 1, and clinical deterioration due to increase of the numbness severity despite significant reduction of pain was seen once. Conclusions: Pituitary radiosurgery for thalamic pain results in a high rate of initial efficacy and is accompanied by acceptable morbidity. It can be used as a primary minimally invasive management option for patients with post-stroke thalamic pain resistant to medical therapy. However, in the majority of cases pain recurrence occurs within 1 year after treatment

Multicentre European study of thalamic stimulation in parkinsonian and essential tremor

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Limousin, P.; Speelman, J. D.; Gielen, F.; Janssens, M.

1999-01-01

Thalamic stimulation has been proposed to treat disabling tremor. The aims of this multicentre study were to evaluate the efficacy and the morbidity of thalamic stimulation in a large number of patients with parkinsonian or essential tremor. One hundred and eleven patients were included in the study

Distinct Thalamic Reticular Cell Types Differentially Modulate Normal and Pathological Cortical Rhythms

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Alexandra Clemente-Perez

2017-06-01

Full Text Available Integrative brain functions depend on widely distributed, rhythmically coordinated computations. Through its long-ranging connections with cortex and most senses, the thalamus orchestrates the flow of cognitive and sensory information. Essential in this process, the nucleus reticularis thalami (nRT gates different information streams through its extensive inhibition onto other thalamic nuclei, however, we lack an understanding of how different inhibitory neuron subpopulations in nRT function as gatekeepers. We dissociated the connectivity, physiology, and circuit functions of neurons within rodent nRT, based on parvalbumin (PV and somatostatin (SOM expression, and validated the existence of such populations in human nRT. We found that PV, but not SOM, cells are rhythmogenic, and that PV and SOM neurons are connected to and modulate distinct thalamocortical circuits. Notably, PV, but not SOM, neurons modulate somatosensory behavior and disrupt seizures. These results provide a conceptual framework for how nRT may gate incoming information to modulate brain-wide rhythms.

Global suppression of electrocortical activity in unilateral perinatal thalamic stroke.

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Kharoshankaya, Liudmila

2014-07-01

We present an unusual case of persistent generalized electroencephalography (EEG) suppression and right-sided clonic seizures in a male infant born at 40(+2) weeks\\' gestation, birthweight 3240g, with an isolated unilateral thalamic stroke. The EEG at 13 hours after birth showed a generalized very low amplitude background pattern, which progressed to frequent electrographic seizures over the left hemisphere. The interictal background EEG pattern remained grossly abnormal over the next 48 hours, showing very low background amplitudes (<10μV). Magnetic resonance imaging revealed an isolated acute left-sided thalamic infarction. This is the first description of severe global EEG suppression caused by an isolated unilateral thalamic stroke and supports the role of the thalamus as the control centre for cortical electrical activity.

Hypertensive thalamic hemorrhage. Clinical symptoms and outcomes in 40 cases

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Munaka, Masahiro; Nishikawa, Michio; Hirai, Osamu; Kaneko, Takaaki; Watanabe, Syu; Fukuma, Jun; Handa, Hajime

1988-12-01

In the past six years, we have had experience with 40 patients with hypertensive thalamic hemorrhages, as verified by CT scan at our hospital within 24 hours. These patients were classified into the following three groups according to the location of the bleeding point and the size of the hematoma: (1) anteromedial (4 cases), (2) posterolateral (16 cases), and (3) massive (20 cases). The (1) and (2) hematomas were small (less than 3 cm in diameter), while those in (3) were large (more than 3 cm in diameter). Twenty cases (50% of all the thalamic hematomas) were small hematomas. The characteristic clinical symptoms of the anteromedial type were a mild disturbance of consciousness and thalamic dementia, while those of the posterolateral type were motor and sensory disturbance, and thalamic aphasia, respectively. Twenty cases (50%) were large hematomas. The clinical symptoms of these cases were mainly consciousness disturbance; 7 of them expired. Based on this experience, it may be considered that the patients whose hematoma size was larger than 3 cm had a poor prognosis and that the patients with the posterolateral type had a poor functional diagnosis.

Grey matter volume patterns in thalamic nuclei are associated with familial risk for schizophrenia.

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Pergola, Giulio; Trizio, Silvestro; Di Carlo, Pasquale; Taurisano, Paolo; Mancini, Marina; Amoroso, Nicola; Nettis, Maria Antonietta; Andriola, Ileana; Caforio, Grazia; Popolizio, Teresa; Rampino, Antonio; Di Giorgio, Annabella; Bertolino, Alessandro; Blasi, Giuseppe

2017-02-01

Previous evidence suggests reduced thalamic grey matter volume (GMV) in patients with schizophrenia (SCZ). However, it is not considered an intermediate phenotype for schizophrenia, possibly because previous studies did not assess the contribution of individual thalamic nuclei and employed univariate statistics. Here, we hypothesized that multivariate statistics would reveal an association of GMV in different thalamic nuclei with familial risk for schizophrenia. We also hypothesized that accounting for the heterogeneity of thalamic GMV in healthy controls would improve the detection of subjects at familial risk for the disorder. We acquired MRI scans for 96 clinically stable SCZ, 55 non-affected siblings of patients with schizophrenia (SIB), and 249 HC. The thalamus was parceled into seven regions of interest (ROIs). After a canonical univariate analysis, we used GMV estimates of thalamic ROIs, together with total thalamic GMV and premorbid intelligence, as features in Random Forests to classify HC, SIB, and SCZ. Then, we computed a Misclassification Index for each individual and tested the improvement in SIB detection after excluding a subsample of HC misclassified as patients. Random Forests discriminated SCZ from HC (accuracy=81%) and SIB from HC (accuracy=75%). Left anteromedial thalamic volumes were significantly associated with both multivariate classifications (p<0.05). Excluding HC misclassified as SCZ improved greatly HC vs. SIB classification (Cohen's d=1.39). These findings suggest that multivariate statistics identify a familial background associated with thalamic GMV reduction in SCZ. They also suggest the relevance of inter-individual variability of GMV patterns for the discrimination of individuals at familial risk for the disorder. Copyright © 2016 Elsevier B.V. All rights reserved.

What does a comparison of the alcoholic Korsakoff syndrome and thalamic infarction tell us about thalamic amnesia?

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Kopelman, Michael D

2015-07-01

In this review, the clinical, neuropsychological, and neuroimaging findings in the alcoholic Korsakoff syndrome and in thalamic amnesia, resulting from focal infarction, are compared. In both disorders, there is controversy over what is the critical site for anterograde amnesia to occur-damage to the anterior thalamus/mammillo-thalamic tract has most commonly been cited, but damage to the medio-dorsal nuclei has also been advocated. Both syndromes show 'core' features of an anterograde amnesic syndrome; but retrograde amnesia is generally much more extensive (going back many years or decades) in the Korsakoff syndrome. Likewise, spontaneous confabulation occurs more commonly in the Korsakoff syndrome, although seen in only a minority of chronic cases. These differences are attributed to the greater prevalence of frontal atrophy and frontal damage in Korsakoff cases. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

Allopregnanolone induces state-dependent fear via the bed nucleus of the stria terminalis.

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Acca, Gillian M; Mathew, Abel S; Jin, Jingji; Maren, Stephen; Nagaya, Naomi

2017-03-01

Gonadal steroids and their metabolites have been shown to be important modulators of emotional behavior. Allopregnanolone (ALLO), for example, is a metabolite of progesterone that has been linked to anxiety-related disorders such as posttraumatic stress disorder. In rodents, it has been shown to reduce anxiety in a number of behavioral paradigms including Pavlovian fear conditioning. We have recently found that expression of conditioned contextual (but not auditory) freezing in rats can be suppressed by infusion of ALLO into the bed nucleus of the stria terminalis (BNST). To further explore the nature of this effect, we infused ALLO into the BNST of male rats prior to both conditioning and testing. We found that suppression of contextual fear occurred when the hormone was present during either conditioning or testing but not during both procedures, suggesting that ALLO acts in a state-dependent manner within the BNST. A shift in interoceptive context during testing for animals conditioned under ALLO provided further support for this mechanism of hormonal action on contextual fear. Interestingly, infusions of ALLO into the basolateral amygdala produced a state-independent suppression of both conditioned contextual and auditory freezing. Altogether, these results suggest that ALLO can influence the acquisition and expression of fear memories by both state-dependent and state-independent mechanisms. Copyright © 2017 Elsevier Inc. All rights reserved.

Impairments of thalamic resting-state functional connectivity in patients with chronic tinnitus

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Zhang, Jian [Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing (China); Chen, Yu-Chen [Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing (China); Center for Hearing and Deafness, University at Buffalo, State University of New York, Buffalo, NY (United States); Feng, Xu [Department of Otolaryngology, Zhongda Hospital, Medical School, Southeast University, Nanjing (China); Yang, Ming; Liu, Bin; Qian, Cheng [Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing (China); Wang, Jian [Department of Physiology, Southeast University, Nanjing (China); School of Human Communication Disorders, Dalhousie University, Halifax, NS (Canada); Salvi, Richard [Center for Hearing and Deafness, University at Buffalo, State University of New York, Buffalo, NY (United States); Teng, Gao-Jun, E-mail: gjteng@vip.sina.com [Jiangsu Key Laboratory of Molecular and Functional Imaging, Department of Radiology, Zhongda Hospital, Medical School, Southeast University, Nanjing (China)

2015-07-15

Highlights: • Tinnitus patients have aberrant thalamic connectivity to many brain regions. • Decreased thalamic connectivity is linked with tinnitus characteristics. • Thalamocortical connectivity disturbances can reflect tinnitus-related networks. - Abstract: Purpose: The phantom sound of tinnitus is believed to arise from abnormal functional coupling between the thalamus and cerebral cortex. To explore this hypothesis, we used resting-state functional magnetic resonance imaging (fMRI) to compare the degree of thalamocortical functional connectivity in chronic tinnitus patients and controls. Materials and methods: Resting-state fMRI scans were obtained from 31 chronic tinnitus patients and 33 well-matched healthy controls. Thalamocortical functional connectivity was characterized using a seed-based whole-brain correlation method. The resulting thalamic functional connectivity measures were correlated with other clinical data. Results: We found decreased functional connectivity between the seed region in left thalamus and right middle temporal gyrus (MTG), right middle orbitofrontal cortex, left middle frontal gyrus, right precentral gyrus, and bilateral calcarine cortex. Decreased functional connectivity was detected between the seed in the right thalamus and the left superior temporal gyrus (STG), left amygdala, right superior frontal gyrus, left precentral gyrus, and left middle occipital gyrus. Tinnitus distress correlated negatively with thalamic functional connectivity in right MTG; tinnitus duration correlated negatively with thalamic functional connectivity in left STG. Increased functional connectivity between the bilateral thalamus and a set of regions were also observed. Conclusions: Chronic tinnitus patients have disrupted thalamocortical functional connectivity to selected brain regions which is associated with specific tinnitus characteristics. Resting-state thalamic functional connectivity disturbances may play an important role in

Impairments of thalamic resting-state functional connectivity in patients with chronic tinnitus

International Nuclear Information System (INIS)

Zhang, Jian; Chen, Yu-Chen; Feng, Xu; Yang, Ming; Liu, Bin; Qian, Cheng; Wang, Jian; Salvi, Richard; Teng, Gao-Jun

2015-01-01

Highlights: • Tinnitus patients have aberrant thalamic connectivity to many brain regions. • Decreased thalamic connectivity is linked with tinnitus characteristics. • Thalamocortical connectivity disturbances can reflect tinnitus-related networks. - Abstract: Purpose: The phantom sound of tinnitus is believed to arise from abnormal functional coupling between the thalamus and cerebral cortex. To explore this hypothesis, we used resting-state functional magnetic resonance imaging (fMRI) to compare the degree of thalamocortical functional connectivity in chronic tinnitus patients and controls. Materials and methods: Resting-state fMRI scans were obtained from 31 chronic tinnitus patients and 33 well-matched healthy controls. Thalamocortical functional connectivity was characterized using a seed-based whole-brain correlation method. The resulting thalamic functional connectivity measures were correlated with other clinical data. Results: We found decreased functional connectivity between the seed region in left thalamus and right middle temporal gyrus (MTG), right middle orbitofrontal cortex, left middle frontal gyrus, right precentral gyrus, and bilateral calcarine cortex. Decreased functional connectivity was detected between the seed in the right thalamus and the left superior temporal gyrus (STG), left amygdala, right superior frontal gyrus, left precentral gyrus, and left middle occipital gyrus. Tinnitus distress correlated negatively with thalamic functional connectivity in right MTG; tinnitus duration correlated negatively with thalamic functional connectivity in left STG. Increased functional connectivity between the bilateral thalamus and a set of regions were also observed. Conclusions: Chronic tinnitus patients have disrupted thalamocortical functional connectivity to selected brain regions which is associated with specific tinnitus characteristics. Resting-state thalamic functional connectivity disturbances may play an important role in

Active action potential propagation but not initiation in thalamic interneuron dendrites

Science.gov (United States)

Casale, Amanda E.; McCormick, David A.

2012-01-01

Inhibitory interneurons of the dorsal lateral geniculate nucleus of the thalamus modulate the activity of thalamocortical cells in response to excitatory input through the release of inhibitory neurotransmitter from both axons and dendrites. The exact mechanisms by which release can occur from dendrites are, however, not well understood. Recent experiments using calcium imaging have suggested that Na/K based action potentials can evoke calcium transients in dendrites via local active conductances, making the back-propagating action potential a candidate for dendritic neurotransmitter release. In this study, we employed high temporal and spatial resolution voltage-sensitive dye imaging to assess the characteristics of dendritic voltage deflections in response to Na/K action potentials in interneurons of the mouse dorsal lateral geniculate nucleus. We found that trains or single action potentials elicited by somatic current injection or local synaptic stimulation led to action potentials that rapidly and actively back-propagated throughout the entire dendritic arbor and into the fine filiform dendritic appendages known to release GABAergic vesicles. Action potentials always appeared first in the soma or proximal dendrite in response to somatic current injection or local synaptic stimulation, and the rapid back-propagation into the dendritic arbor depended upon voltage-gated sodium and TEA-sensitive potassium channels. Our results indicate that thalamic interneuron dendrites integrate synaptic inputs that initiate action potentials, most likely in the axon initial segment, that then back-propagate with high-fidelity into the dendrites, resulting in a nearly synchronous release of GABA from both axonal and dendritic compartments. PMID:22171033

Effect of Spinal Cord Stimulation on Gait in a Patient with Thalamic Pain

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Arito Yozu

2016-01-01

Full Text Available Thalamic pain is a central neuropathic pain disorder which occurs after stroke. Its severe chronic pain is often intractable to pharmacotherapies and affects the patients’ activities of daily living (ADL and quality of life (QOL. Recently, spinal cord stimulation (SCS has been reported to be effective in relieving the pain of thalamic pain; however, the effect of SCS on gait performance in patients is unknown. Therefore, we evaluated the gait performance before and after SCS in a case with thalamic pain. A 73-year-old male with thalamic pain participated in this study. We evaluated the gait of the patient two times: before SCS insertion and after 6 days of SCS. At the second evaluation, we measured the gait in three conditions: stimulation off, comfortable stimulation, and strong stimulation. SCS succeeded in improving the pain from 7 to 2 on an 11-point numerical rating scale. Step frequency and the velocity of gait tended to increase between pre- and poststimulation periods. There were no apparent differences in gait among the three stimulation conditions (off, comfortable, and strong at the poststimulation period. SCS may be effective on gait in patients with thalamic pain.

Differential impact of thalamic versus subthalamic deep brain stimulation on lexical processing.

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Krugel, Lea K; Ehlen, Felicitas; Tiedt, Hannes O; Kühn, Andrea A; Klostermann, Fabian

2014-10-01

Roles of subcortical structures in language processing are vague, but, interestingly, basal ganglia and thalamic Deep Brain Stimulation can go along with reduced lexical capacities. To deepen the understanding of this impact, we assessed word processing as a function of thalamic versus subthalamic Deep Brain Stimulation. Ten essential tremor patients treated with thalamic and 14 Parkinson׳s disease patients with subthalamic Deep Brain Stimulation performed an acoustic Lexical Decision Task ON and OFF stimulation. Combined analysis of task performance and event-related potentials allowed the determination of processing speed, priming effects, and N400 as neurophysiological correlate of lexical stimulus processing. 12 age-matched healthy participants acted as control subjects. Thalamic Deep Brain Stimulation prolonged word decisions and reduced N400 potentials. No comparable ON-OFF effects were present in patients with subthalamic Deep Brain Stimulation. In the latter group of patients with Parkinson' disease, N400 amplitudes were, however, abnormally low, whether under active or inactive Deep Brain Stimulation. In conclusion, performance speed and N400 appear to be influenced by state functions, modulated by thalamic, but not subthalamic Deep Brain Stimulation, compatible with concepts of thalamo-cortical engagement in word processing. Clinically, these findings specify cognitive sequels of Deep Brain Stimulation in a target-specific way. Copyright © 2014 Elsevier Ltd. All rights reserved.

Thalamic neuron models encode stimulus information by burst-size modulation

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Daniel Henry Elijah

2015-09-01

Full Text Available Thalamic neurons have been long assumed to fire in tonic mode during perceptive states, and in burst mode during sleep and unconsciousness. However, recent evidence suggests that bursts may also be relevant in the encoding of sensory information. Here we explore the neural code of such thalamic bursts. In order to assess whether the burst code is generic or whether it depends on the detailed properties of each bursting neuron, we analyzed two neuron models incorporating different levels of biological detail. One of the models contained no information of the biophysical processes entailed in spike generation, and described neuron activity at a phenomenological level. The second model represented the evolution of the individual ionic conductances involved in spiking and bursting, and required a large number of parameters. We analyzed the models' input selectivity using reverse correlation methods and information theory. We found that n-spike bursts from both models transmit information by modulating their spike count in response to changes to instantaneous input features, such as slope, phase, amplitude, etc. The stimulus feature that is most efficiently encoded by bursts, however, need not coincide with one of such classical features. We therefore searched for the optimal feature among all those that could be expressed as a linear transformation of the time-dependent input current. We found that bursting neurons transmitted 6 times more information about such more general features. The relevant events in the stimulus were located in a time window spanning ~100 ms before and ~20 ms after burst onset. Most importantly, the neural code employed by the simple and the biologically realistic models was largely the same, implying that the simple thalamic neuron model contains the essential ingredients that account for the computational properties of the thalamic burst code. Thus, our results suggest the n-spike burst code is a general property of

Thalamic neuron models encode stimulus information by burst-size modulation.

Science.gov (United States)

Elijah, Daniel H; Samengo, Inés; Montemurro, Marcelo A

2015-01-01

Thalamic neurons have been long assumed to fire in tonic mode during perceptive states, and in burst mode during sleep and unconsciousness. However, recent evidence suggests that bursts may also be relevant in the encoding of sensory information. Here, we explore the neural code of such thalamic bursts. In order to assess whether the burst code is generic or whether it depends on the detailed properties of each bursting neuron, we analyzed two neuron models incorporating different levels of biological detail. One of the models contained no information of the biophysical processes entailed in spike generation, and described neuron activity at a phenomenological level. The second model represented the evolution of the individual ionic conductances involved in spiking and bursting, and required a large number of parameters. We analyzed the models' input selectivity using reverse correlation methods and information theory. We found that n-spike bursts from both models transmit information by modulating their spike count in response to changes to instantaneous input features, such as slope, phase, amplitude, etc. The stimulus feature that is most efficiently encoded by bursts, however, need not coincide with one of such classical features. We therefore searched for the optimal feature among all those that could be expressed as a linear transformation of the time-dependent input current. We found that bursting neurons transmitted 6 times more information about such more general features. The relevant events in the stimulus were located in a time window spanning ~100 ms before and ~20 ms after burst onset. Most importantly, the neural code employed by the simple and the biologically realistic models was largely the same, implying that the simple thalamic neuron model contains the essential ingredients that account for the computational properties of the thalamic burst code. Thus, our results suggest the n-spike burst code is a general property of thalamic neurons.

Complex neurological symptoms in bilateral thalamic stroke due to Percheron artery occlusion.

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Caruso, Paola; Manganotti, Paolo; Moretti, Rita

2017-01-01

The artery of Percheron is a rare anatomical variant where a single thalamic perforating artery arises from the proximal posterior cerebral artery (P1 segment) between the basilar artery and the posterior communicating artery and supplies the rostral mesencephalon and both paramedian territories of the thalami. Almost one-third of human brains present this variant. Occlusion of the artery of Percheron mostly results in a bilateral medial thalamic infarction, which usually manifests with altered consciousness (including coma), vertical gaze paresis, and cognitive disturbance. The presentation is similar to the "top of the basilar syndrome", and early recognition should be prompted. We describe the case of a young female with this vessel variant who experienced a bilateral thalamic stroke. Magnetic resonance angiography demonstrated bilateral thalamic infarcts and a truncated artery of Percheron. Occlusion of the vessel was presumably due to embolism from a patent foramen ovale. Thrombolysis was performed, with incomplete symptom remission, cognitive impairment, and persistence of speech disorders. Early recognition and treatment of posterior circulation strokes is mandatory, and further investigation for underlying stroke etiologies is needed.

Thalamic connections of the core auditory cortex and rostral supratemporal plane in the macaque monkey.

Science.gov (United States)

Scott, Brian H; Saleem, Kadharbatcha S; Kikuchi, Yukiko; Fukushima, Makoto; Mishkin, Mortimer; Saunders, Richard C

2017-11-01

In the primate auditory cortex, information flows serially in the mediolateral dimension from core, to belt, to parabelt. In the caudorostral dimension, stepwise serial projections convey information through the primary, rostral, and rostrotemporal (AI, R, and RT) core areas on the supratemporal plane, continuing to the rostrotemporal polar area (RTp) and adjacent auditory-related areas of the rostral superior temporal gyrus (STGr) and temporal pole. In addition to this cascade of corticocortical connections, the auditory cortex receives parallel thalamocortical projections from the medial geniculate nucleus (MGN). Previous studies have examined the projections from MGN to auditory cortex, but most have focused on the caudal core areas AI and R. In this study, we investigated the full extent of connections between MGN and AI, R, RT, RTp, and STGr using retrograde and anterograde anatomical tracers. Both AI and R received nearly 90% of their thalamic inputs from the ventral subdivision of the MGN (MGv; the primary/lemniscal auditory pathway). By contrast, RT received only ∼45% from MGv, and an equal share from the dorsal subdivision (MGd). Area RTp received ∼25% of its inputs from MGv, but received additional inputs from multisensory areas outside the MGN (30% in RTp vs. 1-5% in core areas). The MGN input to RTp distinguished this rostral extension of auditory cortex from the adjacent auditory-related cortex of the STGr, which received 80% of its thalamic input from multisensory nuclei (primarily medial pulvinar). Anterograde tracers identified complementary descending connections by which highly processed auditory information may modulate thalamocortical inputs. © 2017 Wiley Periodicals, Inc.

α(2A)-adrenergic receptors filter parabrachial inputs to the bed nucleus of the stria terminalis.

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Flavin, Stephanie A; Matthews, Robert T; Wang, Qin; Muly, E Chris; Winder, Danny G

2014-07-09

α2-adrenergic receptors (AR) within the bed nucleus of the stria terminalis (BNST) reduce stress-reward interactions in rodent models. In addition to their roles as autoreceptors, BNST α(2A)-ARs suppress glutamatergic transmission. One prominent glutamatergic input to the BNST originates from the parabrachial nucleus (PBN) and consists of asymmetric axosomatic synapses containing calcitonin gene-related peptide (CGRP) and vGluT2. Here we provide immunoelectron microscopic data showing that many asymmetric axosomatic synapses in the BNST contain α(2A)-ARs. Further, we examined optically evoked glutamate release ex vivo in BNST from mice with virally delivered channelrhodopsin2 (ChR2) expression in PBN. In BNST from these animals, ChR2 partially colocalized with CGRP, and activation generated EPSCs in dorsal anterolateral BNST neurons that elicited two cell-type-specific outcomes: (1) feedforward inhibition or (2) an EPSP that elicited firing. We found that the α(2A)-AR agonist guanfacine selectively inhibited this PBN input to the BNST, preferentially reducing the excitatory response in ex vivo mouse brain slices. To begin to assess the overall impact of α(2A)-AR control of this PBN input on BNST excitatory transmission, we used a Thy1-COP4 mouse line with little postsynaptic ChR2 expression nor colocalization of ChR2 with CGRP in the BNST. In slices from these mice, we found that guanfacine enhanced, rather than suppressed, optogenetically initiated excitatory drive in BNST. Thus, our study reveals distinct actions of PBN afferents within the BNST and suggests that α(2A)-AR agonists may filter excitatory transmission in the BNST by inhibiting a component of the PBN input while enhancing the actions of other inputs. Copyright © 2014 the authors 0270-6474/14/349319-13$15.00/0.

Desipramine and citalopram attenuate pretest swim-induced increases in prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis and the lateral division of the central nucleus of the amygdala in the forced swimming test.

Science.gov (United States)

Chung, Sung; Kim, Hee Jeong; Kim, Hyun Ju; Choi, Sun Hye; Cho, Jin Hee; Cho, Yun Ha; Kim, Dong-Hoon; Shin, Kyung Ho

2014-10-01

Dynorphin in the nucleus accumbens shell plays an important role in antidepressant-like effect in the forced swimming test (FST), but it is unclear whether desipramine and citalopram treatments alter prodynorphin levels in other brain areas. To explore this possibility, we injected mice with desipramine and citalopram 0.5, 19, and 23 h after a 15-min pretest swim and observed changes in prodynorphin expression before the test swim, which was conducted 24 h after the pretest swim. The pretest swim increased prodynorphin immunoreactivity in the dorsal bed nucleus of the stria terminalis (dBNST) and lateral division of the central nucleus of the amygdala (CeL). This increase in prodynorphin immunoreactivity in the dBNST and CeL was blocked by desipramine and citalopram treatments. Similar changes in prodynorphin mRNA levels were observed in the dBNST and CeL, but these changes did not reach significance. To understand the underlying mechanism, we assessed changes in phosphorylated CREB at Ser(133) (pCREB) immunoreactivity in the dBNST and central nucleus of the amygdala (CeA). Treatment with citalopram but not desipramine after the pretest swim significantly increased pCREB immunoreactivity only in the dBNST. These results suggest that regulation of prodynorphin in the dBNST and CeL before the test swim may be involved in the antidepressant-like effect of desipramine and citalopram in the FST and suggest that changes in pCREB immunoreactivity in these areas may not play an important role in the regulation of prodynorphin in the dBNST and CeA. Copyright © 2014 Elsevier Ltd. All rights reserved.

Characterization of in vivo MRI detectable thalamic amyloid plaques from APP/PS1 mice

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Dhenain, M. [URA CEA CNRS 2210, I2BM, SHFJ, 4 Place du General Leclerc, 91401 Orsay Cedex (France); Dhenain, M.; El Tannir El Tayara, N.; Wu, T.D.; Volk, A.; Quintana, C. [U759 INSERM, Centre Universitaire, Laboratoire 112, 91405 Orsay Cedex (France); Dhenain, M.; El Tannir El Tayara, N.; Wu, T.D.; Volk, A.; Quintana, C. [Institut Curie, Centre Universitaire, Laboratoire 112, 91405 Orsay Cedex (France); Guegan, M.; Delatour, B. [Instituto de Microelectronica de Madrid-CSIC, 8, Isaac Newton, 28760 Tres Cantos, Madrid (Spain)

2009-07-01

Amyloid deposits are one of the hallmarks of Alzheimer's disease. Recent studies, in transgenic mice modeling Alzheimer's disease showed that, using in vivo, contrast agent-free, MRI, thalamic amyloid plaques are more easily detected than other plaques of the brain. Our study evaluated the characteristics of these thalamic plaques in a large population of APP/PS1, PS1 and C57BL/6 mice. Thalamic spots were detected in all mice but with different frequency and magnitude. Hence, the prevalence and size of the lesions were higher in APP/PS1 mice. However, even in APP/PS1 mice, thalamic spots did not occur in all the old animals. In APP/PS1 mice, spots detection was related to high iron and calcium load within amyloid plaques and thus reflects the ability of such plaque to capture large amounts of minerals. Interestingly, calcium and iron was also detected in extra-thalamic plaques but with a lower intensity. Hypointense lesions in the thalamus were not associated with the iron load in the tissue surrounding the plaques, nor with micro-hemorrhages, inflammation, or a neuro-degenerative context. (authors)

PET Mapping for Brain-Computer Interface Stimulation of the Ventroposterior Medial Nucleus of the Thalamus in Rats with Implanted Electrodes.

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Zhu, Yunqi; Xu, Kedi; Xu, Caiyun; Zhang, Jiacheng; Ji, Jianfeng; Zheng, Xiaoxiang; Zhang, Hong; Tian, Mei

2016-07-01

Brain-computer interface (BCI) technology has great potential for improving the quality of life for neurologic patients. This study aimed to use PET mapping for BCI-based stimulation in a rat model with electrodes implanted in the ventroposterior medial (VPM) nucleus of the thalamus. PET imaging studies were conducted before and after stimulation of the right VPM. Stimulation induced significant orienting performance. (18)F-FDG uptake increased significantly in the paraventricular thalamic nucleus, septohippocampal nucleus, olfactory bulb, left crus II of the ansiform lobule of the cerebellum, and bilaterally in the lateral septum, amygdala, piriform cortex, endopiriform nucleus, and insular cortex, but it decreased in the right secondary visual cortex, right simple lobule of the cerebellum, and bilaterally in the somatosensory cortex. This study demonstrated that PET mapping after VPM stimulation can identify specific brain regions associated with orienting performance. PET molecular imaging may be an important approach for BCI-based research and its clinical applications. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

Effects of donepezil on behavioural manifestations of thalamic infarction: a single case observation

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Rodrigo eRiveros

2011-03-01

Full Text Available Objective: To examine the effect of donepezil for the treatment of cognitive and behavioural disorders associated with thalamic lesions in a 45 years old male who suffered an infarct in the left thalamus. Background: Recent studies suggest that donepezil may improve executive functions impairments due to subcortical ischemic lesionsMethod: The crossover effects of donepezil were analyzed in a single case of thalamic infarction with cognitive and behavioural alterations. Results: Significant behavioural modifications related to improved performances in executive functions were observed with the treatment. Conclusions: The results suggest that donepezil may have significant effect on executive functions that can alter behavioural outcomes after thalamic infarctions

Frontotemporal dementia with severe thalamic involvement : a clinical and neuropathological study

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Radanovic Márcia

2003-01-01

Full Text Available Frontotemporal dementia (FTD is the third-leading cause of cortical dementia after Alzheimer's disease and Lewy body dementia, and is characterized by a dementia where behavioral disturbances are prominent and appear early in the course of the disease. We report the case of a 58 year-old man affected by dementia with behavioral disturbances, in addition to rigid-hypokinetic and a lower motor neuron syndrome that were present at later stages of the illness. Neuroimaging studies showed frontotemporal atrophy. Neuropathological studies revealed intense thalamic neuronal loss and astrocytic gliosis, as well as moderate frontotemporal neuronal loss, astrocytosis and spongiform degeneration. Thalamic degeneration has previously been described among the wide group of neuropathological features of FTD. The aim of the present study is to show the clinical and neuropathological aspects of thalamic degeneration in FTD, along with its role in behavioral disturbances, a common finding in this condition.

Dissociation of Recognition and Recency Memory Judgments After Anterior Thalamic Nuclei Lesions in Rats

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Dumont, Julie R.; Aggleton, John P.

2013-01-01

The anterior thalamic nuclei form part of a network for episodic memory in humans. The importance of these nuclei for recognition and recency judgments remains, however, unclear. Rats with anterior thalamic nuclei lesions and their controls were tested on object recognition, along with two types of recency judgment. The spontaneous discrimination of a novel object or a novel odor from a familiar counterpart (recognition memory) was not affected by anterior thalamic lesions when tested after retention delays of 1 and 60 min. To measure recency memory, rats were shown two familiar objects, one of which had been explored more recently. In one condition, rats were presented with two lists (List A, List B) of objects separated by a delay, thereby creating two distinct blocks of stimuli. After an additional delay, rats were presented with pairs of objects, one from List A and one from List B (between-block recency). No lesion-induced deficit was apparent for recency discriminations between objects from different lists, despite using three different levels of task difficulty. In contrast, rats with anterior thalamic lesions were significantly impaired when presented with a continuous list of objects and then tested on their ability to distinguish between those items early and late in the same list (within-block recency). The contrasting effects on recognition and recency support the notion that interlinked hippocampal–anterior thalamic interconnections support aspects of both spatial and nonspatial learning, although the role of the anterior thalamic nuclei may be restricted to a subclass of recency judgments (within-block). PMID:23731076

Thalamic lesions in multiple sclerosis by 7T MRI: Clinical implications and relationship to cortical pathology.

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Harrison, Daniel M; Oh, Jiwon; Roy, Snehashis; Wood, Emily T; Whetstone, Anna; Seigo, Michaela A; Jones, Craig K; Pham, Dzung; van Zijl, Peter; Reich, Daniel S; Calabresi, Peter A

2015-08-01

Pathology in both cortex and deep gray matter contribute to disability in multiple sclerosis (MS). We used the increased signal-to-noise ratio of 7-tesla (7T) MRI to visualize small lesions within the thalamus and to relate this to clinical information and cortical lesions. We obtained 7T MRI scans on 34 MS cases and 15 healthy volunteers. Thalamic lesion number and volume were related to demographic data, clinical disability measures, and lesions in cortical gray matter. Thalamic lesions were found in 24/34 of MS cases. Two lesion subtypes were noted: discrete, ovoid lesions, and more diffuse lesional areas lining the periventricular surface. The number of thalamic lesions was greater in progressive MS compared to relapsing-remitting (mean ±SD, 10.7 ±0.7 vs. 3.0 ±0.7, respectively, p < 0.001). Thalamic lesion burden (count and volume) correlated with EDSS score and measures of cortical lesion burden, but not with white matter lesion burden or white matter volume. Using 7T MRI allows identification of thalamic lesions in MS, which are associated with disability, progressive disease, and cortical lesions. Thalamic lesion analysis may be a simpler, more rapid estimate of overall gray matter lesion burden in MS. © The Author(s), 2015.

Morphological Abnormalities of Thalamic Subnuclei in Migraine

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Magon, Stefano; May, Arne; Stankewitz, Anne

2015-01-01

UNLABELLED: The thalamus contains third-order relay neurons of the trigeminal system, and animal models as well as preliminary imaging studies in small cohorts of migraine patients have suggested a role of the thalamus in headache pathophysiology. However, larger studies using advanced imaging te...... is a disorder of the CNS in which not only is brain function abnormal, but also brain structure is undergoing significant remodeling....... a fully automated multiatlas approach. Deformation-based shape analysis was performed to localize surface abnormalities. Differences between patients with migraine and healthy subjects were assessed using an ANCOVA model. After correction for multiple comparisons, performed using the false discovery rate.......9) was observed in patients. This large-scale study indicates structural thalamic abnormalities in patients with migraine. The thalamic nuclei with abnormal volumes are densely connected to the limbic system. The data hence lend support to the view that higher-order integration systems are altered in migraine...

Localization of Basal Ganglia and Thalamic Damage in Dyskinetic Cerebral Palsy.

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Aravamuthan, Bhooma R; Waugh, Jeff L

2016-01-01

Dyskinetic cerebral palsy affects 15%-20% of patients with cerebral palsy. Basal ganglia injury is associated with dyskinetic cerebral palsy, but the patterns of injury within the basal ganglia predisposing to dyskinetic cerebral palsy are unknown, making treatment difficult. For example, deep brain stimulation of the globus pallidus interna improves dystonia in only 40% of patients with dyskinetic cerebral palsy. Basal ganglia injury heterogeneity may explain this variability. To investigate this, we conducted a qualitative systematic review of basal ganglia and thalamic damage in dyskinetic cerebral palsy. Reviews and articles primarily addressing genetic or toxic causes of cerebral palsy were excluded yielding 22 studies (304 subjects). Thirteen studies specified the involved basal ganglia nuclei (subthalamic nucleus, caudate, putamen, globus pallidus, or lentiform nuclei, comprised by the putamen and globus pallidus). Studies investigating the lentiform nuclei (without distinguishing between the putamen and globus pallidus) showed that all subjects (19 of 19) had lentiform nuclei damage. Studies simultaneously but independently investigating the putamen and globus pallidus also showed that all subjects (35 of 35) had lentiform nuclei damage (i.e., putamen or globus pallidus damage); this was followed in frequency by damage to the putamen alone (70 of 101, 69%), the subthalamic nucleus (17 of 25, 68%), the thalamus (88 of 142, 62%), the globus pallidus (7/35, 20%), and the caudate (6 of 47, 13%). Globus pallidus damage was almost always coincident with putaminal damage. Noting consistent involvement of the lentiform nuclei in dyskinetic cerebral palsy, these results could suggest two groups of patients with dyskinetic cerebral palsy: those with putamen-predominant damage and those with panlenticular damage involving both the putamen and the globus pallidus. Differentiating between these groups could help predict response to therapies such as deep brain

Accelerated forgetting of contextual details due to focal medio-dorsal thalamic lesion

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Sicong eTu

2014-09-01

Full Text Available Effects of thalamic nuclei damage and related white matter tracts on memory performance are still debated. This is particularly evident for the medio-dorsal thalamus which has been less clear in predicting amnesia than anterior thalamus changes. The current study addresses this issue by assessing 7 thalamic stroke patients with consistent unilateral lesions focal to the left medio-dorsal nuclei for immediate and delayed memory performance on standard visual and verbal tests of anterograde memory, and over the long-term (> 24 hrs on an object-location associative memory task. Thalamic patients showed selective impairment to delayed recall, but intact recognition memory. Patients also showed accelerated forgetting of contextual information after a 24 hour delay, compared to controls. Importantly, the mammillothalamic tract was intact in all patients, which suggests a role for the medio-dorsal nuclei in recall and early consolidation memory processes.

Cerebellar Ataxia from Multiple Potential Causes: Hypothyroidism, Hashimoto's Thyroiditis, Thalamic Stimulation, and Essential Tremor

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Natalya V. Shneyder

2012-04-01

Full Text Available Background: Both hypothyroidism and Hashimoto's thyroiditis (HT can rarely be associated with cerebellar ataxia. Severe essential tremor (ET as well as bilateral thalamic deep brain stimulation (DBS may lead to subtle cerebellar signs. Case Report: We report a 74-year-old male with hypothyroidism and a 20-year history of ET who developed cerebellar ataxia after bilateral thalamic DBS. Extensive workup revealed elevated thyroid stimulating hormone and thyroperoxidase antibody titers confirming the diagnosis of HT. Discussion: Our case demonstrates multiple possible causes of cerebellar ataxia in a patient, including hypothyroidism, HT, chronic ET, and bilateral thalamic DBS. Counseling of patients may be appropriate when multiple risk factors for cerebellar ataxia coexist in one individual.

Thalamic reticular impairment underlies attention deficit in Ptchd1(Y/-) mice.

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Wells, Michael F; Wimmer, Ralf D; Schmitt, L Ian; Feng, Guoping; Halassa, Michael M

2016-04-07

Developmental disabilities, including attention-deficit hyperactivity disorder (ADHD), intellectual disability (ID), and autism spectrum disorders (ASD), affect one in six children in the USA. Recently, gene mutations in patched domain containing 1 (PTCHD1) have been found in ~1% of patients with ID and ASD. Individuals with PTCHD1 deletion show symptoms of ADHD, sleep disruption, hypotonia, aggression, ASD, and ID. Although PTCHD1 is probably critical for normal development, the connection between its deletion and the ensuing behavioural defects is poorly understood. Here we report that during early post-natal development, mouse Ptchd1 is selectively expressed in the thalamic reticular nucleus (TRN), a group of GABAergic neurons that regulate thalamocortical transmission, sleep rhythms, and attention. Ptchd1 deletion attenuates TRN activity through mechanisms involving small conductance calcium-dependent potassium currents (SK). TRN-restricted deletion of Ptchd1 leads to attention deficits and hyperactivity, both of which are rescued by pharmacological augmentation of SK channel activity. Global Ptchd1 deletion recapitulates learning impairment, hyper-aggression, and motor defects, all of which are insensitive to SK pharmacological targeting and not found in the TRN-restricted deletion mouse. This study maps clinically relevant behavioural phenotypes onto TRN dysfunction in a human disease model, while also identifying molecular and circuit targets for intervention.

Particle correlations in proton-nucleus and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Nagamiya, Sh.

1981-01-01

Particle correlations in proton-nucleus and nucleus-nucleus collisions at energies of 1-2 GeV/nucleon are investigated. The problems of measurement of the mean free path lambda of protons inside the nucleus and the interaction radius of nucleus-nucleus collisions is considered. The value of lambda has been determined in two-proton coincidence experiment in proton-nucleus interaction at 800 MeV. The observed value of lambda is slightly longer than the expected from free nucleon-nucleon collisions. Some preliminary results on proton emission beyond free nucleon-nucleon kinemaics are given

Decoding thalamic afferent input using microcircuit spiking activity.

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Sederberg, Audrey J; Palmer, Stephanie E; MacLean, Jason N

2015-04-01

A behavioral response appropriate to a sensory stimulus depends on the collective activity of thousands of interconnected neurons. The majority of cortical connections arise from neighboring neurons, and thus understanding the cortical code requires characterizing information representation at the scale of the cortical microcircuit. Using two-photon calcium imaging, we densely sampled the thalamically evoked response of hundreds of neurons spanning multiple layers and columns in thalamocortical slices of mouse somatosensory cortex. We then used a biologically plausible decoder to characterize the representation of two distinct thalamic inputs, at the level of the microcircuit, to reveal those aspects of the activity pattern that are likely relevant to downstream neurons. Our data suggest a sparse code, distributed across lamina, in which a small population of cells carries stimulus-relevant information. Furthermore, we find that, within this subset of neurons, decoder performance improves when noise correlations are taken into account. Copyright © 2015 the American Physiological Society.

From Parkinsonian thalamic activity to restoring thalamic relay using deep brain stimulation: new insights from computational modeling

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Meijer, H. G. E.; Krupa, M.; Cagnan, H.; Lourens, M. A. J.; Heida, T.; Martens, H. C. F.; Bour, L. J.; van Gils, S. A.

2011-10-01

We present a computational model of a thalamocortical relay neuron for exploring basal ganglia thalamocortical loop behavior in relation to Parkinson's disease and deep brain stimulation (DBS). Previous microelectrode, single-unit recording studies demonstrated that oscillatory interaction within and between basal ganglia nuclei is very often accompanied by synchronization at Parkinsonian rest tremor frequencies (3-10 Hz). These oscillations have a profound influence on thalamic projections and impair the thalamic relaying of cortical input by generating rebound action potentials. Our model describes convergent inhibitory input received from basal ganglia by the thalamocortical cells based on characteristics of normal activity, and/or low-frequency oscillations (activity associated with Parkinson's disease). In addition to simulated input, we also used microelectrode recordings as inputs for the model. In the resting state, and without additional sensorimotor input, pathological rebound activity is generated for even mild Parkinsonian input. We have found a specific stimulation window of amplitudes and frequencies for periodic input, which corresponds to high-frequency DBS, and which also suppresses rebound activity for mild and even more prominent Parkinsonian input. When low-frequency pathological rebound activity disables the thalamocortical cell's ability to relay excitatory cortical input, a stimulation signal with parameter settings corresponding to our stimulation window can restore the thalamocortical cell's relay functionality.

Neonatal thalamic hemorrhage is strongly associated with electrical status epilepticus in slow wave sleep.

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Kersbergen, Karina J; de Vries, Linda S; Leijten, Frans S S; Braun, Kees P J; Nievelstein, Rutger A J; Groenendaal, Floris; Benders, Manon J N L; Jansen, Floor E

2013-04-01

Thalamic hemorrhage has been associated with neonatal cerebral sinovenous thrombosis (CSVT), especially when the straight sinus is involved, and often presents with neonatal seizures. Early thalamic injury has previously been shown to predispose to epilepsy and electrical status epilepticus in slow wave sleep (ESES). The objective of this study was to assess the prevalence of sleep-induced epileptic electroencephalography (EEG) abnormalities and postneonatal epilepsy after neonatal thalamic hemorrhage associated with CSVT, in the absence of more widespread cerebral damage. Between 2003 and 2008 15 neonates were diagnosed with a thalamic hemorrhage due to suspected or proven CSVT. Neurodevelopment and the history of seizures were assessed at follow-up in the outpatient clinic in all 14 survivors (age 2-9 years). Whole-night or sleep-deprived EEG recordings were obtained to assess the prevalence of interictal epileptiform activity (EA) and calculate a sleep-induced spike and wave index (SWI). Three children were diagnosed with classic ESES (SWI >85%). Two children had ESES spectrum disorder (SWI between 50% and 85%), and in two children significant sleep-induced epileptiform activity (SIEA) was noted (SWI between 25% and 50%). Two other children were diagnosed with focal epilepsy, in the absence of sleep-induced epileptiform EEG abnormalities. Five children (age 2-7 years) had normal EEG recordings at follow-up. Deficits in neurodevelopment were seen significantly more often in children with ESES, ESES spectrum, or SIEA. Neonates with thalamic hemorrhage associated with straight sinus thrombosis, without evidence of more widespread cerebral damage, are at high risk of developing ESES (spectrum) disorder (35%), SIEA (14%), or focal epilepsy (14%). Electrographic abnormalities may already be present prior to recognition of cognitive deficits. Early diagnosis may guide parents and caregivers, and subsequent treatment may improve neurodevelopmental outcome. Routine

External pallidal stimulation improves parkinsonian motor signs and modulates neuronal activity throughout the basal ganglia thalamic network.

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Vitek, Jerrold L; Zhang, Jianyu; Hashimoto, Takao; Russo, Gary S; Baker, Kenneth B

2012-01-01

Deep brain stimulation (DBS) of the internal segment of the globus pallidus (GPi) and the subthalamic nucleus (STN) are effective for the treatment of advanced Parkinson's disease (PD). We have shown previously that DBS of the external segment of the globus pallidus (GPe) is associated with improvements in parkinsonian motor signs; however, the mechanism of this effect is not known. In this study, we extend our findings on the effect of STN and GPi DBS on neuronal activity in the basal ganglia thalamic network to include GPe DBS using the 1-methyl-4-phenyl-1.2.3.6-tetrahydropyridine (MPTP) monkey model. Stimulation parameters that improved bradykinesia were associated with changes in the pattern and mean discharge rate of neuronal activity in the GPi, STN, and the pallidal [ventralis lateralis pars oralis (VLo) and ventralis anterior (VA)] and cerebellar [ventralis lateralis posterior pars oralis (VPLo)] receiving areas of the motor thalamus. Population post-stimulation time histograms revealed a complex pattern of stimulation-related inhibition and excitation for the GPi and VA/VLo, with a more consistent pattern of inhibition in STN and excitation in VPLo. Mean discharge rate was reduced in the GPi and STN and increased in the VPLo. Effective GPe DBS also reduced bursting in the STN and GPi. These data support the hypothesis that therapeutic DBS activates output from the stimulated structure and changes the temporal pattern of neuronal activity throughout the basal ganglia thalamic network and provide further support for GPe as a potential therapeutic target for DBS in the treatment of PD. Copyright © 2011 Elsevier Inc. All rights reserved.

Role of the thalamic parafascicular nucleus cholinergic system in the modulation of acute corneal nociception in rats

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Esmaeal Tamaddonfard

2011-11-01

Full Text Available The present study investigated the effects of microinjections of acetylcholine (a cholinergic agonist, physostigmine (a cholinesterase inhibitor, atropine (an antagonist of muscarinic cholinergic receptors and hexamethonium (an antagonist of nicotinic cholinergic receptors into the parafascicular nucleus of thalamus on the acute corneal nociception in rats. Acute corneal nociception was induced by putting a drop of 5 M NaCl solution onto the corneal surface of the eye and the number of eye wipes was counted during the first 30s. Both acetylcholine and physostigmine at the same doses of 0.5, 1 and 2 μg significantly (P < 0.05 reduced the number of eye wipes. The intensity of corneal nociception was not changed when atropine and hexamethonium were used alone. Atropine (4 μg, but not hexamethonium (4 μg significantly (P < 0.05 prevented acetylcholine (2 μg- and physostigmine (2 μg-induced antinociceptive effects. The results indicated that at the level of the parafascicular nucleus of thalamus, the muscarinic cholinergic receptors might be involved in the antinociceptive effects of acetylcholine and physostigmine.

Cortically-controlled population stochastic facilitation as a plausible substrate for guiding sensory transfer across the thalamic gateway.

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Sébastien Béhuret

Full Text Available The thalamus is the primary gateway that relays sensory information to the cerebral cortex. While a single recipient cortical cell receives the convergence of many principal relay cells of the thalamus, each thalamic cell in turn integrates a dense and distributed synaptic feedback from the cortex. During sensory processing, the influence of this functional loop remains largely ignored. Using dynamic-clamp techniques in thalamic slices in vitro, we combined theoretical and experimental approaches to implement a realistic hybrid retino-thalamo-cortical pathway mixing biological cells and simulated circuits. The synaptic bombardment of cortical origin was mimicked through the injection of a stochastic mixture of excitatory and inhibitory conductances, resulting in a gradable correlation level of afferent activity shared by thalamic cells. The study of the impact of the simulated cortical input on the global retinocortical signal transfer efficiency revealed a novel control mechanism resulting from the collective resonance of all thalamic relay neurons. We show here that the transfer efficiency of sensory input transmission depends on three key features: i the number of thalamocortical cells involved in the many-to-one convergence from thalamus to cortex, ii the statistics of the corticothalamic synaptic bombardment and iii the level of correlation imposed between converging thalamic relay cells. In particular, our results demonstrate counterintuitively that the retinocortical signal transfer efficiency increases when the level of correlation across thalamic cells decreases. This suggests that the transfer efficiency of relay cells could be selectively amplified when they become simultaneously desynchronized by the cortical feedback. When applied to the intact brain, this network regulation mechanism could direct an attentional focus to specific thalamic subassemblies and select the appropriate input lines to the cortex according to the descending

Assessment of paramedian thalamic infarcts: MR imaging, clinical features and prognosis

International Nuclear Information System (INIS)

Weidauer, Stefan; Zanella, Friedhelm E.; Lanfermann, Heinrich; Nichtweiss, Michael

2004-01-01

Considering the highly variable vascular supply of the thalamic nuclei, MRI and clinical syndromes can be heterogeneous in ischemic diseases. We attempt to determine MRI pattern and to analyse neurological features and prognosis of paramedian infarcts. In a prospective case series within 5 years from 1999 to 2003, MRI, MRA and clinical symptoms of 38 consecutive patients were analysed. The inferomedial (posterior thalamoperforating artery) territory was affected in 89%, and lesions in the anterolateral (tuberothalamic artery) territory occurred in 42%. However, definite attribution to anterolateral or inferomedial territories was not possible in 13%. Neurological manifestations were somnolence (87%), hemisyndromes (79%), cognitive deficits (58%), oculomotor nerve palsies (53%) and vertical gaze palsies (39%). The most common aetiologies were cardiac embolism (42%), intraarterial embolism (16%), small vessel disease (13%) and large artery arteriosclerosis (13%). Pathological MRA findings were encountered in 55%, and in 18%, lesions were only visible on diffusion-weighted imaging. Correlation of MRI pattern and neurological symptoms points out anterolateral thalamic lesions as the cause of amnestic deficits. Intracranial MRA allows a non-invasive prediction of basilar tip occlusion. Our results underline the necessity of additional diffusion-weighted imaging in detecting small thalamic and midbrain lesions. (orig.)

Nucleus-nucleus potential with repulsive core and elastic scattering. Part 1. Nucleus-nucleus interaction potential

International Nuclear Information System (INIS)

Davidovs'ka, O.Yi.; Denisov, V.Yu.; Nesterov, V.O.

2010-01-01

Various approaches for nucleus-nucleus interaction potential evaluation are discussed in details. It is shown that the antisymmetrization of nucleons belonging to different nuclei and the Pauli principle give the essential contribution into the nucleus-nucleus potential at distances, when nuclei are strongly overlapping, and lead to appearance of the repulsive core of nucleus nucleus interaction at small distances between nuclei.

Medial thalamic 18-FDG uptake following inescapable shock correlates with subsequent learned helpless behavior

International Nuclear Information System (INIS)

Mirrione, M.M.; Schulz, D.; Dewey, S.L.; Henn, F.A.

2009-01-01

in additional regions analyzed including the nucleus accumbens, caudate putamen, substantia nigra, and amygdala. These data suggest that medial thalamic 18-FDG uptake during inescapable shock may contribute to subsequent escape deficits, and are not confounded by shock effects per se, since all animals received the same treatment prior to scanning. We have previously explored 18-FDG differences following the escape test session which also showed hyperactivity in the medial thalamus of learned helpless animals compared to non-learned helpless, and included additional cortical-limbic changes. Given the neuroanatomical connections between the medial thalamus (and habenula) with the prefrontal cortex and monoaminergic brain stem, one possible speculation is that abnormal neuronal activity in these areas during stress may set in motion circuitry changes that correlate with learned helpless behavior.

Cerebellar Ataxia from Multiple Potential Causes: Hypothyroidism, Hashimoto's Thyroiditis, Thalamic Stimulation, and Essential Tremor

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Shneyder, Natalya; Lyons, Mark K.; Driver-dunckley, Erika; Evidente, Virgilio Gerald H.

2012-01-01

Background: Both hypothyroidism and Hashimoto's thyroiditis (HT) can rarely be associated with cerebellar ataxia. Severe essential tremor (ET) as well as bilateral thalamic deep brain stimulation (DBS) may lead to subtle cerebellar signs. Case Report: We report a 74-year-old male with hypothyroidism and a 20-year history of ET who developed cerebellar ataxia after bilateral thalamic DBS. Extensive workup revealed elevated thyroid stimulating hormone and thyroperoxidase antibody titers c...

Activation of Hypocretin-1/Orexin-A Neurons Projecting to the Bed Nucleus of the Stria Terminalis and Paraventricular Nucleus Is Critical for Reinstatement of Alcohol Seeking by Neuropeptide S.

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Ubaldi, Massimo; Giordano, Antonio; Severi, Ilenia; Li, Hongwu; Kallupi, Marsida; de Guglielmo, Giordano; Ruggeri, Barbara; Stopponi, Serena; Ciccocioppo, Roberto; Cannella, Nazzareno

2016-03-15

Environmental conditioning is a major trigger for relapse in abstinent addicts. We showed that activation of the neuropeptide S (NPS) system exacerbates reinstatement vulnerability to cocaine and alcohol via stimulation of the hypocretin-1/orexin-A (Hcrt-1/Ox-A) system. Combining pharmacologic manipulations with immunohistochemistry techniques, we sought to determine how NPS and Hcrt-1/Ox-A systems interact to modulate reinstatement of alcohol seeking in rats. Intrahypothalamic injection of NPS facilitated discriminative cue-induced reinstatement of alcohol seeking. This effect was blocked by the selective Hcrt-1/Ox-A antagonist SB334867 microinjected into the hypothalamic paraventricular nucleus (PVN) or into the bed nucleus of the stria terminalis (BNST) but not into the ventral tegmental area or the locus coeruleus. Combining double labeling and confocal microscopy analyses, we found that NPS-containing axons are in close apposition to hypothalamic Hcrt-1/Ox-A positive neurons, a significant proportion of which express NPS receptors, suggesting a direct interaction between the two systems. Retrograde tracing experiments showed that intra-PVN or intra-BNST red fluorobead unilateral injection labeled bilaterally Hcrt-1/Ox-A somata, suggesting that NPS could recruit two distinct neuronal pathways. Confirming this assumption, intra-BNST or PVN Hcrt-1/Ox-A injection enhanced alcohol seeking similarly to hypothalamic NPS injection but to a lesser degree. Results suggest that the Hcrt-1/Ox-A neurocircuitry mediating the facilitation of cue-induced reinstatement by NPS involves structures critically involved in stress regulation such as the PVN and the BNST. These findings open to the tempting hypothesis of a role of the NPS system in modulating the interactions between stress and environmental conditioning factors in drug relapse. Copyright © 2016. Published by Elsevier Inc.

Model-based iterative learning control of Parkinsonian state in thalamic relay neuron

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Liu, Chen; Wang, Jiang; Li, Huiyan; Xue, Zhiqin; Deng, Bin; Wei, Xile

2014-09-01

Although the beneficial effects of chronic deep brain stimulation on Parkinson's disease motor symptoms are now largely confirmed, the underlying mechanisms behind deep brain stimulation remain unclear and under debate. Hence, the selection of stimulation parameters is full of challenges. Additionally, due to the complexity of neural system, together with omnipresent noises, the accurate model of thalamic relay neuron is unknown. Thus, the iterative learning control of the thalamic relay neuron's Parkinsonian state based on various variables is presented. Combining the iterative learning control with typical proportional-integral control algorithm, a novel and efficient control strategy is proposed, which does not require any particular knowledge on the detailed physiological characteristics of cortico-basal ganglia-thalamocortical loop and can automatically adjust the stimulation parameters. Simulation results demonstrate the feasibility of the proposed control strategy to restore the fidelity of thalamic relay in the Parkinsonian condition. Furthermore, through changing the important parameter—the maximum ionic conductance densities of low-threshold calcium current, the dominant characteristic of the proposed method which is independent of the accurate model can be further verified.

Aphasia and unilateral spatial neglect due to acute thalamic hemorrhage: clinical correlations and outcomes.

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Osawa, Aiko; Maeshima, Shinichiro

2016-04-01

Thalamic hemorrhages are associated with a variety of cognitive dysfunctions, and it is well known that such cognitive changes constitute a limiting factor of recovery of the activities of daily living (ADL). The relationship between cognitive dysfunction and hematomas is unclear. In this study, we investigated the relationship between aphasia/neglect and hematoma volume, hematoma type, and the ADL. One hundred fifteen patients with thalamic hemorrhage (70 men and 45 women) were studied. Their mean age was 68.9 ± 10.3 years, and patients with both left and right lesions were included. We calculated hematoma volume and examined the presence or absence of aphasia/neglect and the relationships between these dysfunctions and hematoma volume, hematoma type, and the ADL. Fifty-nine patients were found to have aphasia and 35 were found to have neglect. Although there was no relationship between hematoma type and cognitive dysfunction, hematoma volume showed a correlation with the severity of cognitive dysfunction. The ADL score and ratio of patient discharge for patients with aphasia/neglect were lower than those for patients without aphasia/neglect. We observed a correlation between the hematoma volume in thalamic hemorrhage and cognitive dysfunction. Aphasia/neglect is found frequently in patients with acute thalamic hemorrhage and may influence the ADL.

Neuroanatomical considerations of isolated hearing loss in thalamic hemorrhage

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Nitin Agarwal, M.D.

2016-12-01

Conclusion: Presumably, this neurological deficit was caused by a hypertensive hemorrhage in the posterior right thalamus. The following case and discussion will review the potential neuroanatomical pathways that we suggest could make isolated hearing loss be part of a “thalamic syndrome.”

Disrupted thalamic prefrontal pathways in patients with idiopathic dystonia

NARCIS (Netherlands)

Bonilha, Leonardo; de Vries, Paulien M.; Hurd, Mark W.; Rorden, Chris; Morgan, Paul S.; Besenski, Nada; Bergmann, Kenneth J.; Hinson, Vanessa K.

There are quantifiable abnormalities in water diffusion properties of the white matter in thalamic and prefrontal areas in patients with idiopathic dystonia (ID). However, it is unclear which pathways are disrupted in these patients. Using probabilistic tractography of high resolution DTI, we

Lucid dreams, an atypical sleep disturbance in anterior and mediodorsal thalamic strokes.

Science.gov (United States)

Sagnier, S; Coulon, P; Chaufton, C; Poli, M; Debruxelles, S; Renou, P; Rouanet, F; Olindo, S; Sibon, I

2015-11-01

Cognitive, affective, and behavioural disturbances are commonly reported following thalamic strokes. Conversely, sleep disorders are rarely reported in this context. Herein, we report the cases of two young patients admitted for an ischemic stroke located in the territories of the left pre-mammillary and paramedian arteries. Together with aphasia, memory complaint, impaired attention and executive functions, they reported lucid dreams with catastrophic content or conflicting situations. Lucid dreams are an atypical presentation in thalamic strokes. These cases enlarge the clinical spectrum of sleep-wake disturbances potentially observed after an acute cerebrovascular event. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

Momentum loss in proton-nucleus and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Khan, F.; Townsend, L.W.

1993-12-01

An optical model description, based on multiple scattering theory, of longitudinal momentum loss in proton-nucleus and nucleus-nucleus collisions is presented. The crucial role of the imaginary component of the nucleon-nucleon transition matrix in accounting for longitudinal momentum transfer is demonstrated. Results obtained with this model are compared with Intranuclear Cascade (INC) calculations, as well as with predictions from Vlasov-Uehling-Uhlenbeck (VUU) and quantum molecular dynamics (QMD) simulations. Comparisons are also made with experimental data where available. These indicate that the present model is adequate to account for longitudinal momentum transfer in both proton-nucleus and nucleus-nucleus collisions over a wide range of energies

Correlation of catecholamine levels in the bed nucleus of the stria terminalis and reduced sexual behavior in middle-aged male rats.

Science.gov (United States)

Chen, Joyce C; Tsai, Houng-Wei; Yeh, Kuei-Ying; Tai, Mei-Yun; Tsai, Yuan-Feen

2008-07-01

The correlation between dopamine (DA) and norepinephrine (NE) levels in the bed nucleus of the stria terminalis (BNST) and male sexual behavior was examined in middle-aged rats. Male rats (18-19 months) were divided into: (a) Group MIE, consisting of rats showing mounts, intromissions, and ejaculations; (b) Group MI, composed of rats showing mounts and intromissions, but no ejaculation; and (c) Group NC, consisting of noncopulators. Young adult rats (4-5 months) displaying complete copulatory behavior were used as the control. Tissue levels of DA, NE, and DA metabolites in the BNST were measured by high-pressure liquid chromatography. DA, but not NE, levels in MIE rats were significantly lower than those in young controls. DA and NE levels in MIE rats were significantly higher than those in NC rats. These results suggest that DA and NE in the BNST might play an important role in the control of male sexual behavior in middle-aged rats.

Pre-stimulus thalamic theta power predicts human memory formation.

Science.gov (United States)

Sweeney-Reed, Catherine M; Zaehle, Tino; Voges, Jürgen; Schmitt, Friedhelm C; Buentjen, Lars; Kopitzki, Klaus; Richardson-Klavehn, Alan; Hinrichs, Hermann; Heinze, Hans-Jochen; Knight, Robert T; Rugg, Michael D

2016-09-01

Pre-stimulus theta (4-8Hz) power in the hippocampus and neocortex predicts whether a memory for a subsequent event will be formed. Anatomical studies reveal thalamus-hippocampal connectivity, and lesion, neuroimaging, and electrophysiological studies show that memory processing involves the dorsomedial (DMTN) and anterior thalamic nuclei (ATN). The small size and deep location of these nuclei have limited real-time study of their activity, however, and it is unknown whether pre-stimulus theta power predictive of successful memory formation is also found in these subcortical structures. We recorded human electrophysiological data from the DMTN and ATN of 7 patients receiving deep brain stimulation for refractory epilepsy. We found that greater pre-stimulus theta power in the right DMTN was associated with successful memory encoding, predicting both behavioral outcome and post-stimulus correlates of successful memory formation. In particular, significant correlations were observed between right DMTN theta power and both frontal theta and right ATN gamma (32-50Hz) phase alignment, and frontal-ATN theta-gamma cross-frequency coupling. We draw the following primary conclusions. Our results provide direct electrophysiological evidence in humans of a role for the DMTN as well as the ATN in memory formation. Furthermore, prediction of subsequent memory performance by pre-stimulus thalamic oscillations provides evidence that post-stimulus differences in thalamic activity that index successful and unsuccessful encoding reflect brain processes specifically underpinning memory formation. Finally, the findings broaden the understanding of brain states that facilitate memory encoding to include subcortical as well as cortical structures. Copyright © 2016 Elsevier Inc. All rights reserved.

A Case of Midbrain and Thalamic Infarction Involving Artery of Percheron

Directory of Open Access Journals (Sweden)

Muhammad Almamun

2015-03-01

Full Text Available Blood supply to the thalamus and brainstem have frequent anatomic variations. One of these is where all the perforators to the above areas arise from a single branch of the posterior cerebral artery commonly known as the artery of Percheron. Infarction involving this artery leading to bilateral thalamic and midbrain lesions is not uncommon, but can cause diagnostic difficulties due to the varying clinical presentations possible and the wide differentials. Early brain imaging and diagnosis is important for initiating appropriate treatment. In this case report, we discuss a patient who presented with an artery of Percheron related stroke affecting the mid brain and paramedian thalamic areas. We also discuss the differentials of presentations with similar symptoms.

Mechanisms of High Energy Hadron-Nucleus and Nucleus-Nucleus Collision Processes

International Nuclear Information System (INIS)

Strugalski, Z.

1994-01-01

Mechanisms of high energy hadron-nucleus and nucleus-nucleus collision processes are depicted qualitatively, as prompted experimentally. In hadron-nucleus collisions the interaction of the incident hadron in intranuclear matter is localized in small cylindrical volume, with the radius as large as the strong interaction range is, centered on the hadron course in the nucleus. The nucleon emission is induced by the hadron in its passing through the nucleus; particles are produced via intermediate objects produced in 2 → 2 endoergic reactions of the hadron and its successors with downstream nucleons. In nucleus-nucleus collisions, the outcome of the reaction appears as the composition of statistically independent hadron-nucleus collision outcomes at various impact parameters. Observable effects supporting such mechanisms are discussed. 51 refs

Prognosis of thalamic hemorrhage evaluated by computed tomography

International Nuclear Information System (INIS)

Takahashi, Shinichiro; Sonobe, Makoto; Sugita, Kyoichi; Kuwayama, Naoya

1984-01-01

The present authors have analyzed the correlation between the clinical features and the CT findings in 66 cases of thalamic hemorrhage. Hitachi CT-H and CT-HF apparatuses (256 x 256 matrix) were used at an angle parallel to the OM line. Of the 48 patients with hematoma less than 20 ml, only four died; however, of the 18 patients with hematoma larger than 20 ml, five died. An analysis has been made of the correlation between the occurrence of brain edema in the acute stage and high density in the subthalamic area. The hematoma extending to the subthalamic area was diagnosed by means of high density at the level of 35 mm above the OM line. Of the 13 cases with hematoma in the subthalamic area, acute brain edema occurred in 9 cases. On the other hand, of the 53 cases without hematoma at the subthalamic area, brain edema occurred in only one case. It was concluded that high density in the subthalamic area is a significant index for the occurrence of acute brain edema in a thalamic hemorrhage. (author)

Sex differences in stress-induced social withdrawal: role of brain derived neurotrophic factor in the bed nucleus of the stria terminalis.

Science.gov (United States)

Greenberg, Gian D; Laman-Maharg, Abigail; Campi, Katharine L; Voigt, Heather; Orr, Veronica N; Schaal, Leslie; Trainor, Brian C

2013-01-01

Depression and anxiety disorders are more common in women than men, and little is known about the neurobiological mechanisms that contribute to this disparity. Recent data suggest that stress-induced changes in neurotrophins have opposing effects on behavior by acting in different brain networks. Social defeat has been an important approach for understanding neurotrophin action, but low female aggression levels in rats and mice have limited the application of these methods primarily to males. We examined the effects of social defeat in monogamous California mice (Peromyscus californicus), a species in which both males and females defend territories. We demonstrate that defeat stress increases mature brain-derived neurotrophic factor (BDNF) protein but not mRNA in the bed nucleus of the stria terminalis (BNST) in females but not males. Changes in BDNF protein were limited to anterior subregions of the BNST, and there were no changes in the adjacent nucleus accumbens (NAc). The effects of defeat on social withdrawal behavior and BDNF were reversed by chronic, low doses of the antidepressant sertraline. However, higher doses of sertraline restored social withdrawal and elevated BDNF levels. Acute treatment with a low dose of sertraline failed to reverse the effects of defeat. Infusions of the selective tyrosine-related kinase B receptor (TrkB) antagonist ANA-12 into the anterior BNST specifically increased social interaction in stressed females but had no effect on behavior in females naïve to defeat. These results suggest that stress-induced increases in BDNF in the anterior BNST contribute to the exaggerated social withdrawal phenotype observed in females.

Antiproton production in nucleon-nucleus and nucleus-nucleus collisions at the CERN-SPS

International Nuclear Information System (INIS)

Kadija, K.; Schmitz, N.; Seyboth, P.

1996-01-01

A model for antiproton production in nucleon-nucleus and nucleus-nucleus collisions at 200 GeV per nucleon, based on the wounded nucleon model is developed. The predictions are compared to published nucleon-nucleus and sulphur-nucleus data. The results suggest the presence of similar antiproton production processes in nucleon-nucleus and nucleus-nucleus collisions near midrapidity. (orig.)

Reduced thalamic volume in preterm infants is associated with abnormal white matter metabolism independent of injury

International Nuclear Information System (INIS)

Wisnowski, Jessica L.; Ceschin, Rafael C.; Choi, So Young; Schmithorst, Vincent J.; Painter, Michael J.; Nelson, Marvin D.; Blueml, Stefan; Panigrahy, Ashok

2015-01-01

Altered thalamocortical development is hypothesized to be a key substrate underlying neurodevelopmental disabilities in preterm infants. However, the pathogenesis of this abnormality is not well-understood. We combined magnetic resonance spectroscopy of the parietal white matter and morphometric analyses of the thalamus to investigate the association between white matter metabolism and thalamic volume and tested the hypothesis that thalamic volume would be associated with diminished N-acetyl-aspartate (NAA), a measure of neuronal/axonal maturation, independent of white matter injury. Data from 106 preterm infants (mean gestational age at birth: 31.0 weeks ± 4.3; range 23-36 weeks) who underwent MR examinations under clinical indications were included in this study. Linear regression analyses demonstrated a significant association between parietal white matter NAA concentration and thalamic volume. This effect was above and beyond the effect of white matter injury and age at MRI and remained significant even when preterm infants with punctate white matter lesions (pWMLs) were excluded from the analysis. Furthermore, choline, and among the preterm infants without pWMLs, lactate concentrations were also associated with thalamic volume. Of note, the associations between NAA and choline concentration and thalamic volume remained significant even when the sample was restricted to neonates who were term-equivalent age or older. These observations provide convergent evidence of a neuroimaging phenotype characterized by widespread abnormal thalamocortical development and suggest that the pathogenesis may involve impaired axonal maturation. (orig.)

Reduced thalamic volume in preterm infants is associated with abnormal white matter metabolism independent of injury

Energy Technology Data Exchange (ETDEWEB)

Wisnowski, Jessica L. [Children' s Hospital Los Angeles, Department of Radiology, Los Angeles, CA (United States); University of Pittsburgh, Department of Pediatric Radiology, Children' s Hospital of Pittsburgh of UPMC, Pittsburgh, PA (United States); University of Southern California, Brain and Creativity Institute, Los Angeles, CA (United States); Ceschin, Rafael C. [University of Pittsburgh, Department of Pediatric Radiology, Children' s Hospital of Pittsburgh of UPMC, Pittsburgh, PA (United States); University of Pittsburgh, Department of Biomedical Informatics, Pittsburgh, PA (United States); Choi, So Young [University of Southern California, Brain and Creativity Institute, Los Angeles, CA (United States); Schmithorst, Vincent J. [University of Pittsburgh, Department of Pediatric Radiology, Children' s Hospital of Pittsburgh of UPMC, Pittsburgh, PA (United States); Painter, Michael J. [University of Pittsburgh, Department of Pediatrics, Division of Neurology, Childrens Hospital of Pittsburgh of UPMC, Pittsburgh, PA (United States); Nelson, Marvin D. [Children' s Hospital Los Angeles, Department of Radiology, Los Angeles, CA (United States); Blueml, Stefan [Children' s Hospital Los Angeles, Department of Radiology, Los Angeles, CA (United States); Rudi Schulte Research Institute, Santa Barbara, CA (United States); Panigrahy, Ashok [Children' s Hospital Los Angeles, Department of Radiology, Los Angeles, CA (United States); University of Pittsburgh, Department of Pediatric Radiology, Children' s Hospital of Pittsburgh of UPMC, Pittsburgh, PA (United States)

2015-05-01

Altered thalamocortical development is hypothesized to be a key substrate underlying neurodevelopmental disabilities in preterm infants. However, the pathogenesis of this abnormality is not well-understood. We combined magnetic resonance spectroscopy of the parietal white matter and morphometric analyses of the thalamus to investigate the association between white matter metabolism and thalamic volume and tested the hypothesis that thalamic volume would be associated with diminished N-acetyl-aspartate (NAA), a measure of neuronal/axonal maturation, independent of white matter injury. Data from 106 preterm infants (mean gestational age at birth: 31.0 weeks ± 4.3; range 23-36 weeks) who underwent MR examinations under clinical indications were included in this study. Linear regression analyses demonstrated a significant association between parietal white matter NAA concentration and thalamic volume. This effect was above and beyond the effect of white matter injury and age at MRI and remained significant even when preterm infants with punctate white matter lesions (pWMLs) were excluded from the analysis. Furthermore, choline, and among the preterm infants without pWMLs, lactate concentrations were also associated with thalamic volume. Of note, the associations between NAA and choline concentration and thalamic volume remained significant even when the sample was restricted to neonates who were term-equivalent age or older. These observations provide convergent evidence of a neuroimaging phenotype characterized by widespread abnormal thalamocortical development and suggest that the pathogenesis may involve impaired axonal maturation. (orig.)

Nucleus-nucleus total reaction cross sections

International Nuclear Information System (INIS)

DeVries, R.M.; Peng, J.C.

1980-01-01

We compare sigma/sub R/(E) for nucleus-nucleus systems (obtained from existing direct measurements and derived from elastic scattering data) with nucleon-nucleon and nucleon-nucleus data. The energy dependence of sigma/sub R/(E) for nucleus-nucleus systems is found to be quite rapid; there appears to be no evidence for an energy independent, geometric sigma/sub R/. Simple parameter free microscopic calculations are able to quantitatively reproduce the data and thus, emphasize the dominance of nucleon-nucleon interactions in medium energy nucleus-nucleus collisions

Holmes' tremor as a delayed complication of thalamic stroke.

Science.gov (United States)

Martins, William Alves; Marrone, Luiz Carlos Porcello; Fussiger, Helena; Vedana, Viviane Maria; Cristovam, Rafael do Amaral; Taietti, Marjorye Z; Marrone, Antonio Carlos Huf

2016-04-01

Movement disorders are not commonly associated with stroke. Accordingly, thalamic strokes have rarely been associated with tremor, pseudo-athetosis and dystonic postures. We present a 75-year-old man who developed a disabling tremor 1 year after a posterolateral thalamic stroke. This tremor had low frequency (3-4 Hz), did not disappear on focus and was exacerbated by maintaining a static posture and on target pursuit, which made it very difficult to perform basic functions. MRI demonstrated an old ischemic lesion at the left posterolateral thalamus. Treatment with levodopa led to symptom control. Lesions in the midbrain, cerebellum and thalamus may cause Holmes' tremor. Delayed onset of symptoms is usually seen, sometimes appearing 2 years after the original injury. This may be due to maturation of a complex neuronal network, leading to slow dopaminergic denervation. Further studies are needed to improve our understanding of this unique disconnection syndrome. Copyright © 2015 Elsevier Ltd. All rights reserved.

Bilateral lesions of nucleus subpretectalis/interstitio-pretecto-subpretectalis (SP/IPS) selectively impair figure-ground discrimination in pigeons.

Science.gov (United States)

Scully, Erin N; Acerbo, Martin J; Lazareva, Olga F

2014-01-01

Earlier, we reported that nucleus rotundus (Rt) together with its inhibitory complex, nucleus subpretectalis/interstitio-pretecto-subpretectalis (SP/IPS), had significantly higher activity in pigeons performing figure-ground discrimination than in the control group that did not perform any visual discriminations. In contrast, color discrimination produced significantly higher activity than control in the Rt but not in the SP/IPS. Finally, shape discrimination produced significantly lower activity than control in both the Rt and the SP/IPS. In this study, we trained pigeons to simultaneously perform three visual discriminations (figure-ground, color, and shape) using the same stimulus displays. When birds learned to perform all three tasks concurrently at high levels of accuracy, we conducted bilateral chemical lesions of the SP/IPS. After a period of recovery, the birds were retrained on the same tasks to evaluate the effect of lesions on maintenance of these discriminations. We found that the lesions of the SP/IPS had no effect on color or shape discrimination and that they significantly impaired figure-ground discrimination. Together with our earlier data, these results suggest that the nucleus Rt and the SP/IPS are the key structures involved in figure-ground discrimination. These results also imply that thalamic processing is critical for figure-ground segregation in avian brain.

Motor and cortico-striatal-thalamic connectivity alterations in intrauterine growth restriction.

Science.gov (United States)

Eixarch, Elisenda; Muñoz-Moreno, Emma; Bargallo, Nuria; Batalle, Dafnis; Gratacos, Eduard

2016-06-01

Intrauterine growth restriction is associated with short- and long-term neurodevelopmental problems. Structural brain changes underlying these alterations have been described with the use of different magnetic resonance-based methods that include changes in whole structural brain networks. However, evaluation of specific brain circuits and its correlation with related functions has not been investigated in intrauterine growth restriction. In this study, we aimed to investigate differences in tractography-related metrics in cortico-striatal-thalamic and motor networks in intrauterine growth restricted children and whether these parameters were related with their specific function in order to explore its potential use as an imaging biomarker of altered neurodevelopment. We included a group of 24 intrauterine growth restriction subjects and 27 control subjects that were scanned at 1 year old; we acquired T1-weighted and 30 directions diffusion magnetic resonance images. Each subject brain was segmented in 93 regions with the use of anatomical automatic labeling atlas, and deterministic tractography was performed. Brain regions included in motor and cortico-striatal-thalamic networks were defined based in functional and anatomic criteria. Within the streamlines that resulted from the whole brain tractography, those belonging to each specific circuit were selected and tractography-related metrics that included number of streamlines, fractional anisotropy, and integrity were calculated for each network. We evaluated differences between both groups and further explored the correlation of these parameters with the results of socioemotional, cognitive, and motor scales from Bayley Scale at 2 years of age. Reduced fractional anisotropy (cortico-striatal-thalamic, 0.319 ± 0.018 vs 0.315 ± 0.015; P = .010; motor, 0.322 ± 0.019 vs 0.319 ± 0.020; P = .019) and integrity cortico-striatal-thalamic (0.407 ± 0.040 vs 0.399 ± 0.034; P = .018; motor, 0.417 ± 0.044 vs 0

Nucleus-Nucleus Collision as Superposition of Nucleon-Nucleus Collisions

International Nuclear Information System (INIS)

Orlova, G.I.; Adamovich, M.I.; Aggarwal, M.M.; Alexandrov, Y.A.; Andreeva, N.P.; Badyal, S.K.; Basova, E.S.; Bhalla, K.B.; Bhasin, A.; Bhatia, V.S.; Bradnova, V.; Bubnov, V.I.; Cai, X.; Chasnikov, I.Y.; Chen, G.M.; Chernova, L.P.; Chernyavsky, M.M.; Dhamija, S.; Chenawi, K.El; Felea, D.; Feng, S.Q.; Gaitinov, A.S.; Ganssauge, E.R.; Garpman, S.; Gerassimov, S.G.; Gheata, A.; Gheata, M.; Grote, J.; Gulamov, K.G.; Gupta, S.K.; Gupta, V.K.; Henjes, U.; Jakobsson, B.; Kanygina, E.K.; Karabova, M.; Kharlamov, S.P.; Kovalenko, A.D.; Krasnov, S.A.; Kumar, V.; Larionova, V.G.; Li, Y.X.; Liu, L.S.; Lokanathan, S.; Lord, J.J.; Lukicheva, N.S.; Lu, Y.; Luo, S.B.; Mangotra, L.K.; Manhas, I.; Mittra, I.S.; Musaeva, A.K.; Nasyrov, S.Z.; Navotny, V.S.; Nystrand, J.; Otterlund, I.; Peresadko, N.G.; Qian, W.Y.; Qin, Y.M.; Raniwala, R.; Rao, N.K.; Roeper, M.; Rusakova, V.V.; Saidkhanov, N.; Salmanova, N.A.; Seitimbetov, A.M.; Sethi, R.; Singh, B.; Skelding, D.; Soderstrem, K.; Stenlund, E.; Svechnikova, L.N.; Svensson, T.; Tawfik, A.M.; Tothova, M.; Tretyakova, M.I.; Trofimova, T.P.; Tuleeva, U.I.; Vashisht, Vani; Vokal, S.; Vrlakova, J.; Wang, H.Q.; Wang, X.R.; Weng, Z.Q.; Wilkes, R.J.; Yang, C.B.; Yin, Z.B.; Yu, L.Z.; Zhang, D.H.; Zheng, P.Y.; Zhokhova, S.I.; Zhou, D.C.

1999-01-01

Angular distributions of charged particles produced in 16 O and 32 S collisions with nuclear track emulsion were studied at momenta 4.5 and 200 A GeV/c. Comparison with the angular distributions of charged particles produced in proton-nucleus collisions at the same momentum allows to draw the conclusion, that the angular distributions in nucleus-nucleus collisions can be seen as superposition of the angular distributions in nucleon-nucleus collisions taken at the same impact parameter b NA , that is mean impact parameter between the participating projectile nucleons and the center of the target nucleus

Nucleus-Nucleus Collision as Superposition of Nucleon-Nucleus Collisions

Energy Technology Data Exchange (ETDEWEB)

Orlova, G I; Adamovich, M I; Aggarwal, M M; Alexandrov, Y A; Andreeva, N P; Badyal, S K; Basova, E S; Bhalla, K B; Bhasin, A; Bhatia, V S; Bradnova, V; Bubnov, V I; Cai, X; Chasnikov, I Y; Chen, G M; Chernova, L P; Chernyavsky, M M; Dhamija, S; Chenawi, K El; Felea, D; Feng, S Q; Gaitinov, A S; Ganssauge, E R; Garpman, S; Gerassimov, S G; Gheata, A; Gheata, M; Grote, J; Gulamov, K G; Gupta, S K; Gupta, V K; Henjes, U; Jakobsson, B; Kanygina, E K; Karabova, M; Kharlamov, S P; Kovalenko, A D; Krasnov, S A; Kumar, V; Larionova, V G; Li, Y X; Liu, L S; Lokanathan, S; Lord, J J; Lukicheva, N S; Lu, Y; Luo, S B; Mangotra, L K; Manhas, I; Mittra, I S; Musaeva, A K; Nasyrov, S Z; Navotny, V S; Nystrand, J; Otterlund, I; Peresadko, N G; Qian, W Y; Qin, Y M; Raniwala, R; Rao, N K; Roeper, M; Rusakova, V V; Saidkhanov, N; Salmanova, N A; Seitimbetov, A M; Sethi, R; Singh, B; Skelding, D; Soderstrem, K; Stenlund, E; Svechnikova, L N; Svensson, T; Tawfik, A M; Tothova, M; Tretyakova, M I; Trofimova, T P; Tuleeva, U I; Vashisht, Vani; Vokal, S; Vrlakova, J; Wang, H Q; Wang, X R; Weng, Z Q; Wilkes, R J; Yang, C B; Yin, Z B; Yu, L Z; Zhang, D H; Zheng, P Y; Zhokhova, S I; Zhou, D C

1999-03-01

Angular distributions of charged particles produced in {sup 16}O and {sup 32}S collisions with nuclear track emulsion were studied at momenta 4.5 and 200 A GeV/c. Comparison with the angular distributions of charged particles produced in proton-nucleus collisions at the same momentum allows to draw the conclusion, that the angular distributions in nucleus-nucleus collisions can be seen as superposition of the angular distributions in nucleon-nucleus collisions taken at the same impact parameter b{sub NA}, that is mean impact parameter between the participating projectile nucleons and the center of the target nucleus.

Nucleus-nucleus collision as superposition of nucleon-nucleus collisions

International Nuclear Information System (INIS)

Orlova, G.I.; Adamovich, M.I.; Aggarwal, M.M.

1999-01-01

Angular distributions of charged particles produced in 16 O and 32 S collisions with nuclear track emulsion were studied at momenta 4.5 and 200 A GeV/c. Comparison with the angular distributions of charged particles produced in proton-nucleus collisions at the same momentum allows to draw the conclusion, that the angular distributions in nucleus-nucleus collisions can be seen as superposition of the angular distributions in nucleon-nucleus collisions taken at the same impact parameter b NA , that is mean impact parameter between the participating projectile nucleons and the center of the target nucleus. (orig.)

Contralateral Supracerebellar-Infratentorial Approach for Resection of Thalamic Cavernous Malformations.

Science.gov (United States)

Mascitelli, Justin; Burkhardt, Jan-Karl; Gandhi, Sirin; Lawton, Michael T

2018-02-26

Surgical resection of cavernous malformations (CM) in the posterior thalamus, pineal region, and midbrain tectum is technically challenging owing to the presence of adjacent eloquent cortex and critical neurovascular structures. Various supracerebellar infratentorial (SCIT) approaches have been used in the surgical armamentarium targeting lesions in this region, including the median, paramedian, and extreme lateral variants. Surgical view of a posterior thalamic CM from the traditional ipsilateral vantage point may be obscured by occipital lobe and tentorium. To describe a novel surgical approach via a contralateral SCIT (cSCIT) trajectory for resecting posterior thalamic CMs. From 1997 to 2017, 75 patients underwent the SCIT approach for cerebrovascular/oncologic pathology by the senior author. Of these, 30 patients underwent the SCIT approach for CM resection, and 3 patients underwent the cSCIT approach. Historical patient data, radiographic features, surgical technique, and postoperative neurological outcomes were evaluated in each patient. All 3 patients presented with symptomatic CMs within the right posterior thalamus with radiographic evidence of hemorrhage. All surgeries were performed in the sitting position. There were no intraoperative complications. Neuroimaging demonstrated complete CM resection in all cases. There were no new or worsening neurological deficits or evidence of rebleeding/recurrence noted postoperatively. This study establishes the surgical feasibility of a contralateral SCIT approach in resection of symptomatic thalamic CMs It demonstrates the application for this procedure in extending the surgical trajectory superiorly and laterally and maximizing safe resectability of these deep CMs with gravity-assisted brain retraction.

Thalamo–cortical network underlying deep brain stimulation of centromedian thalamic nuclei in intractable epilepsy: a multimodal imaging analysis

Directory of Open Access Journals (Sweden)

Kim SH

2017-10-01

Full Text Available Seong Hoon Kim,1 Sung Chul Lim,1 Dong Won Yang,1 Jeong Hee Cho,1 Byung-Chul Son,2 Jiyeon Kim,3 Seung Bong Hong,4 Young-Min Shon4 1Department of Neurology, 2Department of Neurosurgery, Catholic Neuroscience Institute, College of Medicine, The Catholic University of Korea, Seoul, 3Department of Neurology, Korea University Ansan Hospital, College of Medicine, Korea University, Ansan, 4Department of Neurology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea Objective: Deep brain stimulation (DBS of the centromedian thalamic nucleus (CM can be an alternative treatment option for intractable epilepsy patients. Since CM may be involved in widespread cortico-subcortical networks, identification of the cortical sub-networks specific to the target stimuli may provide further understanding on the underlying mechanisms of CM DBS. Several brain structures have distinguishing brain connections that may be related to the pivotal propagation and subsequent clinical effect of DBS.Methods: To explore core structures and their connections relevant to CM DBS, we applied electroencephalogram (EEG and diffusion tensor imaging (DTI to 10 medically intractable patients – three generalized epilepsy (GE and seven multifocal epilepsy (MFE patients unsuitable for resective surgery. Spatiotemporal activation pattern was mapped from scalp EEG by delivering low-frequency stimuli (5 Hz. Structural connections between the CM and the cortical activation spots were assessed using DTI.Results: We confirmed an average 72% seizure reduction after CM DBS and its clinical efficiency remained consistent during the observation period (mean 21 months. EEG data revealed sequential source propagation from the anterior cingulate, followed by the frontotemporal regions bilaterally. In addition, maximal activation was found in the left cingulate gyrus and the right medial frontal cortex during the right and left CM stimulation, respectively

Afferent and efferent projections of the anterior cortical amygdaloid nucleus in the mouse.

Science.gov (United States)

Cádiz-Moretti, Bernardita; Abellán-Álvaro, María; Pardo-Bellver, Cecília; Martínez-García, Fernando; Lanuza, Enrique

2017-09-01

The anterior cortical amygdaloid nucleus (ACo) is a chemosensory area of the cortical amygdala that receives afferent projections from both the main and accessory olfactory bulbs. The role of this structure is unknown, partially due to a lack of knowledge of its connectivity. In this work, we describe the pattern of afferent and efferent projections of the ACo by using fluorogold and biotinylated dextranamines as retrograde and anterograde tracers, respectively. The results show that the ACo is reciprocally connected with the olfactory system and basal forebrain, as well as with the chemosensory and basomedial amygdala. In addition, it receives dense projections from the midline and posterior intralaminar thalamus, and moderate projections from the posterior bed nucleus of the stria terminalis, mesocortical structures and the hippocampal formation. Remarkably, the ACo projects moderately to the central nuclei of the amygdala and anterior bed nucleus of the stria terminalis, and densely to the lateral hypothalamus. Finally, minor connections are present with some midbrain and brainstem structures. The afferent projections of the ACo indicate that this nucleus might play a role in emotional learning involving chemosensory stimuli, such as olfactory fear conditioning. The efferent projections confirm this view and, given its direct output to the medial part of the central amygdala and the hypothalamic 'aggression area', suggest that the ACo can initiate defensive and aggressive responses elicited by olfactory or, to a lesser extent, vomeronasal stimuli. © 2017 Wiley Periodicals, Inc.

Some experimental results of the investigation of hadron-nucleus and nucleus-nucleus interactions

International Nuclear Information System (INIS)

Azimov, S.A.; Gulamov, K.G.; Chernov, G.M.

1978-01-01

Recent experimental data on the hadron-nucleus and nucleus-nucleus inelastic interactions are analyzed. A particular attention is paid to the description of the leading hadron spectra and of the spectra of nucleon recoils in hadron-nucleus interactions. Some of the results of the experimental studies of correlations between secondary particles are discussed. This discussion demonstrates that an analysis of the multiparticle phenomena is very promising regarding the discrimination between the different models for the hadron-nucleus and nucleus-nucleus interactions. It is pointed out that the actual mechanism of the hadron-nucleus and nucleus-nucleus interactions is a rather complex one and can be described comprehensively by none of the existing models

Allopregnanolone in the bed nucleus of the stria terminalis modulates contextual fear in rats.

Science.gov (United States)

Nagaya, Naomi; Acca, Gillian M; Maren, Stephen

2015-01-01

Trauma- and stress-related disorders are among the most common types of mental illness affecting the U.S. population. For many of these disorders, there is a striking sex difference in lifetime prevalence; for instance, women are twice as likely as men to be affected by posttraumatic stress disorder (PTSD). Gonadal steroids and their metabolites have been implicated in sex differences in fear and anxiety. One example, allopregnanolone (ALLO), is a neuroactive metabolite of progesterone that allosterically enhances GABAA receptor activity and has anxiolytic effects. Like other ovarian hormones, it not only occurs at different levels in males and females but also fluctuates over the female reproductive cycle. One brain structure that may be involved in neuroactive steroid regulation of fear and anxiety is the bed nucleus of the stria terminalis (BNST). To explore this question, we examined the consequences of augmenting or reducing ALLO activity in the BNST on the expression of Pavlovian fear conditioning in rats. In Experiment 1, intra-BNST infusions of ALLO in male rats suppressed freezing behavior (a fear response) to the conditioned context, but did not influence freezing to a discrete tone conditioned stimulus (CS). In Experiment 2, intra-BNST infusion of either finasteride (FIN), an inhibitor of ALLO synthesis, or 17-phenyl-(3α,5α)-androst-16-en-3-ol, an ALLO antagonist, in female rats enhanced contextual freezing; neither treatment affected freezing to the tone CS. These findings support a role for ALLO in modulating contextual fear via the BNST and suggest that sex differences in fear and anxiety could arise from differential steroid regulation of BNST function. The susceptibility of women to disorders such as PTSD may be linked to cyclic declines in neuroactive steroid activity within fear circuitry.

Allopregnanolone in the bed nucleus of the stria terminalis modulates contextual fear in rats

Directory of Open Access Journals (Sweden)

Naomi eNagaya

2015-08-01

Full Text Available Trauma- and stress-related disorders are among the most common types of mental illness affecting the U.S. population. For many of these disorders, there is a striking sex difference in lifetime prevalence; for instance, women are twice as likely as men to be affected by posttraumatic stress disorder (PTSD. Gonadal steroids and their metabolites have been implicated in sex differences in fear and anxiety. One example, allopregnanolone (ALLO, is a neuroactive metabolite of progesterone that allosterically enhances GABAA receptor activity and has anxiolytic effects. Like other ovarian hormones, it not only occurs at different levels in males and females but also fluctuates over the female reproductive cycle. One brain structure that may be involved in neuroactive steroid regulation of fear and anxiety is the bed nucleus of the stria terminalis (BNST. To explore this question, we examined the consequences of augmenting or reducing ALLO activity in the BNST on the expression of Pavlovian fear conditioning in rats. In Experiment 1, intra-BNST infusions of ALLO in male rats suppressed freezing behavior (a fear response to the conditioned context, but did not influence freezing to a discrete tone conditioned stimulus (CS. In Experiment 2, intra-BNST infusion of either finasteride, an inhibitor of ALLO synthesis, or 17-phenyl-(3α,5α-androst-16-en-3-ol, an ALLO antagonist, in female rats enhanced contextual freezing; neither treatment affected freezing to the tone CS. These findings support a role for ALLO in modulating contextual fear via the BNST and suggest that sex differences in fear and anxiety could arise from differential steroid regulation of BNST function. The susceptibility of women to disorders such as PTSD may be linked to cyclic declines in neuroactive steroid activity within fear circuitry.

Title: Sex differences in stress-induced social withdrawal: role of brain derived neurotrophic factor in the bed nucleus of the stria terminalis

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Gian David Greenberg

2014-01-01

Full Text Available Depression and anxiety disorders are more common in women than men, and little is known about the neurobiological mechanisms that contribute to this disparity. Recent data suggest that stress-induced changes in neurotrophins have opposing effects on behavior by acting in different brain networks. Social defeat has been an important approach for understanding neurotrophin action, but low female aggression levels in rats and mice have limited the application of these methods primarily to males. We examined the effects of social defeat in monogamous California mice (Peromyscus californicus, a species in which both males and females defend territories. We demonstrate that defeat stress increases mature brain-derived neurotrophic factor (BDNF protein but not mRNA in the bed nucleus of the stria terminalis (BNST in females but not males. Changes in BDNF protein were limited to anterior subregions of the BNST, and there were no changes in the adjacent nucleus accumbens (NAc. The effects of defeat on social withdrawal behavior and BDNF were reversed by chronic, low doses of the antidepressant sertraline. However, higher doses of sertraline restored social withdrawal and elevated BDNF levels. Acute treatment with a low dose of sertraline failed to reverse the effects of defeat. Infusions of the selective tyrosine-related kinase B receptor (TrkB antagonist ANA-12 into the anterior BNST specifically increased social interaction in stressed females but had no effect on behavior in females naïve to defeat. These results suggest that stress-induced increases in BDNF in the anterior BNST contribute to the exaggerated social withdrawal phenotype observed in females.

Resting-state functional connectivity of the bed nucleus of the stria terminalis in post-traumatic stress disorder and its dissociative subtype.

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Rabellino, Daniela; Densmore, Maria; Harricharan, Sherain; Jean, Théberge; McKinnon, Margaret C; Lanius, Ruth A

2018-03-01

The bed nucleus of the stria terminals (BNST) is a subcortical structure involved in anticipatory and sustained reactivity to threat and is thus essential to the understanding of anxiety and stress responses. Although chronic stress and anxiety represent a hallmark of post-traumatic stress disorder (PTSD), to date, few studies have examined the functional connectivity of the BNST in PTSD. Here, we used resting state functional Magnetic Resonance Imaging (fMRI) to investigate the functional connectivity of the BNST in PTSD (n = 70), its dissociative subtype (PTSD + DS) (n = 41), and healthy controls (n = 50). In comparison to controls, PTSD showed increased functional connectivity of the BNST with regions of the reward system (ventral and dorsal striatum), possibly underlying stress-induced reward-seeking behaviors in PTSD. By contrast, comparing PTSD + DS to controls, we observed increased functional connectivity of the BNST with the claustrum, a brain region implicated in consciousness and a primary site of kappa-opioid receptors, which are critical to the dynorphin-mediated dysphoric stress response. Moreover, PTSD + DS showed increased functional connectivity of the BNST with brain regions involved in attention and salience detection (anterior insula and caudate nucleus) as compared to PTSD and controls. Finally, BNST functional connectivity positively correlated with default-mode network regions as a function of state identity dissociation, suggesting a role of BNST networks in the disruption of self-relevant processing characterizing the dissociative subtype. These findings represent an important first step in elucidating the role of the BNST in aberrant functional networks underlying PTSD and its dissociative subtype. © 2017 Wiley Periodicals, Inc.

High energy nucleus-nucleus scattering and matter radius of unstable nucleus

International Nuclear Information System (INIS)

Sato, H.; Okuhara, Y.

1985-07-01

The interaction cross sections of high energy nucleus-nucleus scattering have been studied with the Glauber Model and Hartree-Fock like variational calculation for the nuclear structure. It is found that the experimental interaction cross sections of the light unstable nucleus-stable nucleus scatterings measured by INS-LBL collaboration are well reproduceable. (author)

The correlation characteristics of sup 9 Be(d, p gamma) sup 1 sup 0 Be reaction at E sub d = 15.3 MeV and structure of sup 1 sup 0 Be nucleus

CERN Document Server

Zelenskaya, N S; Lebedev, V M; Orlova, N V; Spasskij, A V

2001-01-01

The results of measurements of double differential cross sections of the sup 9 Be(d, p gamma) sup 1 sup 0 Be reaction at E sub d = 15.3 MeV in the forward hemisphere proton ejection angles are presented. The modelless restoration of all even spin-tensor components of the density matrix of the 2 sup + (3.37 MeV) state of residual nucleus is reduced. The angular dependences of magnetic substate population and moment orientation tensor components for this state are also obtained. The experimental results are compared with calculations incorporating the neutron stripping mechanism by coupled-channel method. A large sensitivity of the calculated correlation characteristics to wave functions of nuclei participating in reaction, especially for nucleus sup 1 sup 0 Be is pointed out. It is demonstrated that taking the multistep processes into account is important for the investigated reaction

Lateral and Anterior Thalamic Lesions Impair Independent Memory Systems

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Mitchell, Anna S.; Dalrymple-Alford, John C.

2006-01-01

Damage to the medial region of the thalamus, both in clinical cases (e.g., patients with infarcts or the Korsakoff's syndrome) and animal lesion models, is associated with variable amnesic deficits. Some studies suggest that many of these memory deficits rely on the presence of lateral thalamic lesions (LT) that include the intralaminar nuclei,…

High energy nucleus-nucleus collisions

International Nuclear Information System (INIS)

Bhalla, K.B.

1980-01-01

An attempt is made to explain nucleus-nucleus collisions based on nuclear emulsion experiments. Peripheral and central collisions are described in detail. Assuming the fireball model, the concepts of geometry, kinematics and thermodynamics in this model are discussed. Projectile and target fragmentations are studied. The advantages of using nuclear emulsions as detectors, are mentioned. Proton-nucleus collisions and nucleus-nucleus collisions are compared. Interactions, of projectiles such as Ca, B and C on targets such as Pb, Ag, Br etc. at very high energies (approximately 300 to 1700 Gev) are listed. A comparison of the near multiplicities in these interactions is given. A generalized explanation is given on the processes involved in these interactions. (A.K.)

Passive accessory joint mobilization in the multimodal management of chronic dysesthesia following thalamic stroke.

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Griffin, Kristina; O'Hearn, Michael; Franck, Carla C; Courtney, Carol A

2018-03-20

Case Report. Stroke is the most common cause of long-term disability. Dysesthesia, an unpleasant sensory disturbance, is common following thalamic stroke and evidence-based interventions for this impairment are limited. The purpose of this case report was to describe a decrease in dysesthesia following manual therapy intervention in a patient with history of right lacunar thalamic stroke. A 66-year-old female presented with tingling and dysesthesia in left hemisensory distribution including left trunk and upper/lower extremities, limiting function. Decreased left shoulder active range of motion, positive sensory symptoms but no sensory loss in light touch was found. She denied pain and moderate shoulder muscular weakness was demonstrated. Laterality testing revealed right/left limb discrimination deficits and neglect-like symptoms were reported. Passive accessory joint motion assessment of glenohumeral and thoracic spine revealed hypomobility and provoked dysesthesia. Interventions included passive oscillatory joint mobilization of glenohumeral joint, thoracic spine, ribs and shoulder strengthening. After six sessions, shoulder function, active range of motion, strength improved and dysesthesia decreased. Global Rating of Change Scale was +5 and QuickDASH score decreased from 45% to 22% disability. Laterality testing was unchanged. Manual therapy may be a beneficial intervention in management of thalamic stroke-related dysesthesia. Implications for Rehabilitation While pain is common following thalamic stroke, patients may present with chronic paresthesia or dysesthesia, often in a hemisensory distribution. Passive movement may promote inhibition of hyperexcitable cortical pathways, which may diminish aberrant sensations. Passive oscillatory manual therapy may be an effective way to treat sensory disturbances such as paresthesias or dysesthesia.

Interacting gluon model for hadron-nucleus and nucleus-nucleus collisions in the central rapidity region

International Nuclear Information System (INIS)

Fowler, G.N.; Navarra, F.S.; Plumer, M.; Lawrence Berkeley Laboratory, Nuclear Science Division, Berkeley, California 94720); Vourdas, A.; Weiner, R.M.

1989-01-01

The interacting gluon model developed to describe the inelasticity distribution in hadron-nucleon collisions has been generalized and applied to hadron-nucleus and nucleus-nucleus interactions. Leading particle spectra and energy distributions in hadron-nucleus and nucleus-nucleus collisions are calculated

Mechanisms of Neuroplasticity and Ethanol’s Effects on Plasticity in the Striatum and Bed Nucleus of the Stria Terminalis

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Lovinger, David M.; Kash, Thomas L.

2015-01-01

Long-lasting changes in synaptic function (i.e., synaptic plasticity) have long been thought to contribute to information storage in the nervous system. Although synaptic plasticity mainly has adaptive functions that allow the organism to function in complex environments, it is now clear that certain events or exposure to various substances can produce plasticity that has negative consequences for organisms. Exposure to drugs of abuse, in particular ethanol, is a life experience that can activate or alter synaptic plasticity, often resulting in increased drug seeking and taking and in many cases addiction. Two brain regions subject to alcohol’s effects on synaptic plasticity are the striatum and bed nucleus of the stria terminalis (BNST), both of which have key roles in alcohol’s actions and control of intake. The specific effects depend on both the brain region analyzed (e.g., specific subregions of the striatum and BNST) and the duration of ethanol exposure (i.e., acute vs. chronic). Plastic changes in synaptic transmission in these two brain regions following prolonged ethanol exposure are thought to contribute to excessive alcohol drinking and relapse to drinking. Understanding the mechanisms underlying this plasticity may lead to new therapies for treatment of these and other aspects of alcohol use disorder. PMID:26259092

Altered cortico-striatal-thalamic connectivity in relation to spatial working memory capacity in children with ADHD

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Kathryn L. Mills

2012-01-01

Full Text Available Introduction: Attention deficit hyperactivity disorder (ADHD captures a heterogeneous group of children, who are characterized by a range of cognitive and behavioral symptoms. Previous resting state functional connectivity (rs-fcMRI studies have sought to understand the neural correlates of ADHD by comparing connectivity measurements between those with and without the disorder, focusing primarily on cortical-striatal circuits mediated by the thalamus. To integrate the multiple phenotypic features associated with ADHD and help resolve its heterogeneity, it is helpful to determine how specific circuits relate to unique cognitive domains of the ADHD syndrome. Spatial working memory has been proposed as a key mechanism in the pathophysiology of ADHD.Methods: We correlated the rs-fcMRI of five thalamic regions of interest with spatial span working memory scores in a sample of 67 children aged 7-11 years (ADHD and typically developing children; TDC. In an independent dataset, we then examined group differences in thalamo-striatal functional connectivity between 70 ADHD and 89 TDC (7-11 years from the ADHD-200 dataset. Thalamic regions of interest were created based on previous methods that utilize known thalamo-cortical loops and rs-fcMRI to identify functional boundaries in the thalamus.Results/Conclusions: Using these thalamic regions, we found atypical rs-fcMRI between specific thalamic groupings with the basal ganglia. To identify the thalamic connections that relate to spatial working memory in ADHD, only connections identified in both the correlational and comparative analyses were considered. Multiple connections between the thalamus and basal ganglia, particularly between medial and anterior dorsal thalamus and the putamen, were related to spatial working memory and also altered in ADHD. These thalamo-striatal disruptions may be one of multiple atypical neural and cognitive mechanisms that relate to the ADHD clinical phenotype.

Endogenous oxytocin is necessary for preferential Fos expression to male odors in the bed nucleus of the stria terminalis in female Syrian hamsters.

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Martinez, Luis A; Levy, Marisa J; Petrulis, Aras

2013-09-01

Successful reproduction in mammals depends on proceptive or solicitational behaviors that enhance the probability of encountering potential mates. In female Syrian hamsters, one such behavior is vaginal scent marking. Recent evidence suggests that the neuropeptide oxytocin (OT) may be critical for regulating this behavior. Blockade of OT receptors in the bed nucleus of the stria terminalis (BNST) or the medial preoptic area (MPOA) decreases vaginal marking responses to male odors; lesion data suggest that BNST, rather than MPOA, mediates this effect. However, how OT interacts with sexual odor processing to drive preferential solicitation is not known. To address this issue, intact female Syrian hamsters were exposed to male or female odors and their brains processed for immunohistochemistry for Fos, a marker of recent neuronal activation, and OT. Additional females were injected intracerebroventricularly (ICV) with an oxytocin receptor antagonist (OTA) or vehicle, and then tested for vaginal marking and Fos responses to sexual odors. Colocalization of OT and Fos in the paraventricular nucleus of the hypothalamus was unchanged following exposure to male odors, but decreased following exposure to female odors. Following injections of OTA, Fos expression to male odors was decreased in BNST, but not in MPOA or the medial amygdala (MA). Fos expression in BNST may be functionally relevant for vaginal marking, given that there was a positive correlation between Fos expression and vaginal marking for BNST, but not MPOA or MA. Together, these data suggest that OT facilitation of neuronal activity in BNST underlies the facilitative effects of OT on solicitational responses to male odors. © 2013.

Acute engagement of Gq-mediated signaling in the bed nucleus of the stria terminalis induces anxiety-like behavior.

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Mazzone, C M; Pati, D; Michaelides, M; DiBerto, J; Fox, J H; Tipton, G; Anderson, C; Duffy, K; McKlveen, J M; Hardaway, J A; Magness, S T; Falls, W A; Hammack, S E; McElligott, Z A; Hurd, Y L; Kash, T L

2018-01-01

The bed nucleus of the stria terminalis (BNST) is a brain region important for regulating anxiety-related behavior in both humans and rodents. Here we used a chemogenetic strategy to investigate how engagement of G protein-coupled receptor (GPCR) signaling cascades in genetically defined GABAergic BNST neurons modulates anxiety-related behavior and downstream circuit function. We saw that stimulation of vesicular γ-aminobutyric acid (GABA) transporter (VGAT)-expressing BNST neurons using hM3Dq, but neither hM4Di nor rM3Ds designer receptors exclusively activated by a designer drug (DREADD), promotes anxiety-like behavior. Further, we identified that activation of hM3Dq receptors in BNST VGAT neurons can induce a long-term depression-like state of glutamatergic synaptic transmission, indicating DREADD-induced changes in synaptic plasticity. Further, we used DREADD-assisted metabolic mapping to profile brain-wide network activity following activation of G q -mediated signaling in BNST VGAT neurons and saw increased activity within ventral midbrain structures, including the ventral tegmental area and hindbrain structures such as the locus coeruleus and parabrachial nucleus. These results highlight that G q -mediated signaling in BNST VGAT neurons can drive downstream network activity that correlates with anxiety-like behavior and points to the importance of identifying endogenous GPCRs within genetically defined cell populations. We next used a microfluidics approach to profile the receptorome of single BNST VGAT neurons. This approach yielded multiple G q -coupled receptors that are associated with anxiety-like behavior and several potential novel candidates for regulation of anxiety-like behavior. From this, we identified that stimulation of the G q -coupled receptor 5-HT 2C R in the BNST is sufficient to elevate anxiety-like behavior in an acoustic startle task. Together, these results provide a novel profile of receptors within genetically defined BNST VGAT

Cyto- and chemoarchitecture of the dorsal thalamus of the monotreme Tachyglossus aculeatus, the short beaked echidna.

Science.gov (United States)

Ashwell, Ken W S; Paxinos, George

2005-12-01

We have examined the cyto- and chemoarchitecture of the dorsal thalamus of the short beaked echidna (Tachyglossus aculeatus), using Nissl and myelin staining, immunoreactivity for parvalbumin, calbindin, calretinin and non-phosphorylated neurofilament protein (SMI-32 antibody), and histochemistry for acetylcholinesterase and NADPH diaphorase. Immunohistochemical methods revealed many nuclear boundaries, which were difficult to discern with Nissl staining. Parvalbumin immunoreactive somata were concentrated in the ventral posterior, reticular, posterior, lateral and medial geniculate nuclei, while parvalbumin immunoreactivity of the neuropil was present throughout all but the midline nuclei. Large numbers of calbindin immunoreactive somata were also found within the midline thalamic nuclei, and thalamic sensory relay nuclei. Immunoreactivity for calretinin was found in many small somata within the lateral geniculate "a" nucleus, with other labelled somata found in the lateral geniculate "b" nucleus, ventral posterior medial and ventral posterior lateral nuclei. Immunoreactivity with the SMI-32 antibody was largely confined to somata and neuropil within the thalamocortical relay nuclei (ventral posterior medial and lateral nuclei, lateral and medial geniculate nuclei and the posterior thalamic nucleus). In broad terms there were many similarities between the thalamus of this monotreme and that of eutheria (e.g. disposition of somatosensory thalamus, complementarity of parvalbumin and calbindin immunoreactive structures), but there were some unique features of the thalamus of the echidna. These include the relatively small size of the thalamic reticular nucleus and the preponderance of calbindin immunoreactive neurons over parvalbumin immunoreactive neurons in the ventral posterior nucleus.

Thalamic involvement in the regulation of alpha EEG activity in psychiatric patients

International Nuclear Information System (INIS)

Shirazi, S.P.; Pakula, J.; Young, I.J.; Crayton, J.W.; Konopka, L.M.; Rybak, M.

2002-01-01

Aim: The thalamus is considered to be an important sub-cortical system involved in modulation of cortical activities. A relationship between thalamic activity and surface EEG was recently reported. In this study we evaluated a group of patients with psychiatric disorders who presented with asymmetric perfusion of the thalamus based on brain SPECT HMPAO studies. We predicted that asymmetrical activity of the thalamus would have asymmetrically distributed surface qEEG activity patterns. Materials and Methods: Twenty-three male psychiatric patients (age 54±14) with a primary diagnosis of depression and co-morbid substance abuse (83%) were studied with qEEG and HMPAO brain SPECT. The HMPAO ligand was administered while the EEG activity was being recorded. The SPECT analysis was conducted by means of ROI and SPM. ROI regions were determined based on the Talairach atlas coordinate system. ROI locations were verified by the automated utility, Talairach Demon. QEEG data was analyzed by a standardized protocol involving the NxLink database. Correlations between SPECT findings and qEEG absolute power were calculated. Results: Patients were divided into two groups based on thalamic perfusion patterns. Group 1 (Gr 1) had decreased perfusion to the right thalamus whereas Group 2 (Gr 2) had decreased perfusion to the left thalamus. SPM comparison of the patient groups to normal control subjects indicated significant findings. Comparison of Gr 1 to controls showed increased activity in the left temporal lobe and vermis. Decreased activity was observed in the left and right medial frontal lobes (right Brodmann 9;left Brodmann 6) as well as the left (Brodmann 30) and right (Brodmann 24) cingulate. Gr 2 comparison showed increased activity in the right middle frontal gyrus (Brodmann 10) and left inferior parietal lobe. Decreased activity was found in the left inferior frontal lobe (Brodmann 47). A positive correlation between alpha power and thalamic perfusion was identified in Gr

CT classification of small thalamic hemorrhages

International Nuclear Information System (INIS)

Kawahara, Nobutaka; Kaneko, Mitsuo; Tanaka, Keisei; Muraki, Masaaki; Sato, Kengo

1984-01-01

The thalamus is located deep in the cerebral hemispheres, and most of its nuclei have reciprocal fiber connections with specific areas over the cerebral cortex. Localized lesions in the thalamus, therefore, can cause specific neurological deficits, depending on their locations. From this point of view, we reviewed 110 cases, admitted over the past 7 years, with thalamic hemorrhages 37 (34%) of which were small hematomas less than 2 cm in diameter. These small hematomas could be divided into 4 types depending on their locations as follows: antero-lateral type, postero-lateral type, medial type, and dorsal type. Each type had the peculiar clinical features described below: 1) Postero-lateral Type (PL type, 28 cases, 76%): The original symptom was a sudden onset of moderate to severe sensori-motor deficits in most cases. The patients were mostly alert or only slightly confused. 2) Antero-lateral Type (AL type, 4 cases, 11%): The patients of this type first presented with sensori-motor disturbance and prefrontal signs. Both were generally mild and often disappeared early. 3) Medial Type (M type, 3 cases, 8%): The main symptom at onset was either a disturbance of consciousness or dementia. 4) Dorsal Type (D type, 2 cases, 5%): One patient with a right thalamic hematoma of this type showed geographical agnosia and visuo-constructive apraxia. The other patient, with a left-sided hematoma, exhibited transient clumsiness of the right hand and mild dysphasia. In our experience, the above classification of small hematomas clearly delineated the clinical symptoms and neurological signs of the different types; therefore, the symptoms and signs in larger hematoma could be explained by a combination of those of each type. (J.P.N.)

Thalamic structures and associated cognitive functions: Relations with age and aging

Science.gov (United States)

Fama, Rosemary; Sullivan, Edith V.

2015-01-01

The thalamus, with its cortical, subcortical, and cerebellar connections, is a critical node in networks supporting cognitive functions known to decline in normal aging, including component processes of memory and executive functions of attention and information processing. The macrostructure, microstructure, and neural connectivity of the thalamus changes across the adult lifespan. Structural and functional magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) have demonstrated, regional thalamic volume shrinkage and microstructural degradation, with anterior regions generally more compromised than posterior regions. The integrity of selective thalamic nuclei and projections decline with advancing age, particularly those in thalamofrontal, thalamoparietal, and thalamolimbic networks. This review presents studies that assess the relations between age and aging and the structure, function, and connectivity of the thalamus and associated neural networks and focuses on their relations with processes of attention, speed of information processing, and working and episodic memory. PMID:25862940

The α2δ subunit and absence epilepsy: Beyond calcium channels?

NARCIS (Netherlands)

Celli, R.; Santolini, I.; Guiducci, M.; Luijtelaar, E.L.J.M. van; Parisi, P.; Striano, P.; Gradini, R.; Battaglia, G.; Ngomba, R.T.; Nicoletti, F.

2017-01-01

Spike-wave discharges, underlying absence seizures, are generated within a cortico-thalamo-cortical network that involves the somatosensory cortex, the reticular thalamic nucleus, and the ventrobasal thalamic nuclei. Activation of T-type voltage-sensitive calcium channels (VSCCs) contributes to the

Figure-ground discrimination in the avian brain: the nucleus rotundus and its inhibitory complex.

Science.gov (United States)

Acerbo, Martin J; Lazareva, Olga F; McInnerney, John; Leiker, Emily; Wasserman, Edward A; Poremba, Amy

2012-10-01

In primates, neurons sensitive to figure-ground status are located in striate cortex (area V1) and extrastriate cortex (area V2). Although much is known about the anatomical structure and connectivity of the avian visual pathway, the functional organization of the avian brain remains largely unexplored. To pinpoint the areas associated with figure-ground segregation in the avian brain, we used a radioactively labeled glucose analog to compare differences in glucose uptake after figure-ground, color, and shape discriminations. We also included a control group that received food on a variable-interval schedule, but was not required to learn a visual discrimination. Although the discrimination task depended on group assignment, the stimulus displays were identical for all three experimental groups, ensuring that all animals were exposed to the same visual input. Our analysis concentrated on the primary thalamic nucleus associated with visual processing, the nucleus rotundus (Rt), and two nuclei providing regulatory feedback, the pretectum (PT) and the nucleus subpretectalis/interstitio-pretecto-subpretectalis complex (SP/IPS). We found that figure-ground discrimination was associated with strong and nonlateralized activity of Rt and SP/IPS, whereas color discrimination produced strong and lateralized activation in Rt alone. Shape discrimination was associated with lower activity of Rt than in the control group. Taken together, our results suggest that figure-ground discrimination is associated with Rt and that SP/IPS may be a main source of inhibitory control. Thus, figure-ground segregation in the avian brain may occur earlier than in the primate brain. Copyright © 2012 Elsevier Ltd. All rights reserved.

Diffractive ''semioptical'' model for nucleus-nucleus collisions

International Nuclear Information System (INIS)

Barashenkov, V.S.; Musulmanbekov, Zh.Zh.

1979-01-01

Diffraction Glauber theory for nucleus-nucleus collisions is considered in approximation when the initial nucleus interacts as a whole with nucleons of the target nucleus. Such an approach, being intermediate between precise Glauber theory and its optical limit, essentially simplifies numerical calculations and gives a good agreement with experiments as well. (author)

Thalamic Deep Brain Stimulation for Essential Tremor Also Reduces Voice Tremor.

Science.gov (United States)

Kundu, Bornali; Schrock, Lauren; Davis, Tyler; House, Paul A

2017-12-12

Voice tremor is a common feature of essential tremor (ET) that is difficult to treat medically and significantly affects quality of life. Deep brain stimulation (DBS) of the ventral intermediate nucleus (Vim) of the thalamus is effective in improving contralateral distal limb tremor and has been shown in limited studies to affect voice tremor. Our objective was to retrospectively evaluate whether Vim-DBS used to treat patients with essential motor tremor also effectively treated underlying concurrent voice tremor and assess whether particular lead locations were favorable for treating vocal tremor. In this retrospective cohort study, patients had unilateral or bilateral lead placement and were monitored for up to 12 months. We used the Fahn-Tolosa-Marin (FTM) subscore to assess vocal tremor. Changes in vocal tremor before and after stimulation and over several sessions were assessed. Of the 77 patients who met the inclusion criteria and were treated for essential tremor, 20 (26%) patients had vocal tremor prior to stimulation. Active Vim-DBS decreased the amplitude of voice tremor by 80% (p centroid of stimulation showed that Vim thalamic stimulation that is more anterior on average yielded better voice tremor control, significantly so on the left side (p < 0.05). Additionally, there was improvement in head, tongue, and face tremor scores (p < 0.05). Unilateral and bilateral Vim-DBS targeted to treat the motor component of essential tremor also dramatically decreased the amplitude of voice tremor in this group of patients, suggesting a potential benefit of this treatment for affected patients. © 2017 International Neuromodulation Society.

Thalamic deactivation at sleep onset precedes that of the cerebral cortex in humans

Science.gov (United States)

Magnin, Michel; Rey, Marc; Bastuji, Hélène; Guillemant, Philippe; Mauguière, François; Garcia-Larrea, Luis

2010-01-01

Thalamic and cortical activities are assumed to be time-locked throughout all vigilance states. Using simultaneous intracortical and intrathalamic recordings, we demonstrate here that the thalamic deactivation occurring at sleep onset most often precedes that of the cortex by several minutes, whereas reactivation of both structures during awakening is synchronized. Delays between thalamus and cortex deactivations can vary from one subject to another when a similar cortical region is considered. In addition, heterogeneity in activity levels throughout the cortical mantle is larger than previously thought during the descent into sleep. Thus, asynchronous thalamo-cortical deactivation while falling asleep probably explains the production of hypnagogic hallucinations by a still-activated cortex and the common self-overestimation of the time needed to fall asleep. PMID:20142493

Thalamic control of human attention driven by memory and learning.

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de Bourbon-Teles, José; Bentley, Paul; Koshino, Saori; Shah, Kushal; Dutta, Agneish; Malhotra, Paresh; Egner, Tobias; Husain, Masud; Soto, David

2014-05-05

The role of the thalamus in high-level cognition-attention, working memory (WM), rule-based learning, and decision making-remains poorly understood, especially in comparison to that of cortical frontoparietal networks [1-3]. Studies of visual thalamus have revealed important roles for pulvinar and lateral geniculate nucleus in visuospatial perception and attention [4-10] and for mediodorsal thalamus in oculomotor control [11]. Ventrolateral thalamus contains subdivisions devoted to action control as part of a circuit involving the basal ganglia [12, 13] and motor, premotor, and prefrontal cortices [14], whereas anterior thalamus forms a memory network in connection with the hippocampus [15]. This connectivity profile suggests that ventrolateral and anterior thalamus may represent a nexus between mnemonic and control functions, such as action or attentional selection. Here, we characterize the role of thalamus in the interplay between memory and visual attention. We show that ventrolateral lesions impair the influence of WM representations on attentional deployment. A subsequent fMRI study in healthy volunteers demonstrates involvement of ventrolateral and, notably, anterior thalamus in biasing attention through WM contents. To further characterize the memory types used by the thalamus to bias attention, we performed a second fMRI study that involved learning of stimulus-stimulus associations and their retrieval from long-term memory to optimize attention in search. Responses in ventrolateral and anterior thalamic nuclei tracked learning of the predictiveness of these abstract associations and their use in directing attention. These findings demonstrate a key role for human thalamus in higher-level cognition, notably, in mnemonic biasing of attention. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

[Motor neglect of thalamic origin: report on two cases (author's transl)].

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Laplane, D; Escourolle, R; Degos, J D; Sauron, B; Massiou, H

1982-01-01

Two cases of thalamic lesions with motor neglect are presented. The syndrome of motor neglect was complete in those cases with a) underutilization of left limbs, but good utilization upon verbal orders, b) loss of placement reaction, c) weakness of movement when hand was approaching the target, d) weakness of motor reaction to nociceptive stimuli. Those cases confirm that motor neglect exists after thalamic lesions and bring pathologic clues for topographic discussion. Motor neglect seems to be a particular case of partial unilateral neglect throwing some doubt on the hypothesis of a global trouble of hemispheric activation. Prevalence of left motor neglects suggests some linkage between propositional motility and language. One may suppose that in the right hemisphere language is able to have a vicarious action when spontaneous activation is lost; at the opposite, in the left hemisphere language and motility would be too linked to let this dissociation be generally possible.

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

International Nuclear Information System (INIS)

Akiyama, H.; Harrop, R.; McGeer, P.L.; Peppard, R.; McGeer, E.G.

1989-01-01

We detected crossed cerebellar as well as uncrossed basal ganglia and thalamic diaschisis in Alzheimer's disease by positron emission tomography (PET) using 18 F-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

Impaired visual short-term memory capacity is distinctively associated with structural connectivity of the posterior thalamic radiation and the splenium of the corpus callosum in preterm-born adults.

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Menegaux, Aurore; Meng, Chun; Neitzel, Julia; Bäuml, Josef G; Müller, Hermann J; Bartmann, Peter; Wolke, Dieter; Wohlschläger, Afra M; Finke, Kathrin; Sorg, Christian

2017-04-15

Preterm birth is associated with an increased risk for lasting changes in both the cortico-thalamic system and attention; however, the link between cortico-thalamic and attention changes is as yet little understood. In preterm newborns, cortico-cortical and cortico-thalamic structural connectivity are distinctively altered, with increased local clustering for cortico-cortical and decreased integrity for cortico-thalamic connectivity. In preterm-born adults, among the various attention functions, visual short-term memory (vSTM) capacity is selectively impaired. We hypothesized distinct associations between vSTM capacity and the structural integrity of cortico-thalamic and cortico-cortical connections, respectively, in preterm-born adults. A whole-report paradigm of briefly presented letter arrays based on the computationally formalized Theory of Visual Attention (TVA) was used to quantify parameter vSTM capacity in 26 preterm- and 21 full-term-born adults. Fractional anisotropy (FA) of posterior thalamic radiations and the splenium of the corpus callosum obtained by diffusion tensor imaging were analyzed by tract-based spatial statistics and used as proxies for cortico-thalamic and cortico-cortical structural connectivity. The relationship between vSTM capacity and cortico-thalamic and cortico-cortical connectivity, respectively, was significantly modified by prematurity. In full-term-born adults, the higher FA in the right posterior thalamic radiation the higher vSTM capacity; in preterm-born adults this FA-vSTM-relationship was inversed. In the splenium, higher FA was correlated with higher vSTM capacity in preterm-born adults, whereas no significant relationship was evident in full-term-born adults. These results indicate distinct associations between cortico-thalamic and cortico-cortical integrity and vSTM capacity in preterm-and full-term-born adults. Data suggest compensatory cortico-cortical fiber re-organization for attention deficits after preterm delivery

Increased thalamic resting-state connectivity as a core driver of LSD-induced hallucinations.

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Müller, F; Lenz, C; Dolder, P; Lang, U; Schmidt, A; Liechti, M; Borgwardt, S

2017-12-01

It has been proposed that the thalamocortical system is an important site of action of hallucinogenic drugs and an essential component of the neural correlates of consciousness. Hallucinogenic drugs such as LSD can be used to induce profoundly altered states of consciousness, and it is thus of interest to test the effects of these drugs on this system. 100 μg LSD was administrated orally to 20 healthy participants prior to fMRI assessment. Whole brain thalamic functional connectivity was measured using ROI-to-ROI and ROI-to-voxel approaches. Correlation analyses were used to explore relationships between thalamic connectivity to regions involved in auditory and visual hallucinations and subjective ratings on auditory and visual drug effects. LSD caused significant alterations in all dimensions of the 5D-ASC scale and significantly increased thalamic functional connectivity to various cortical regions. Furthermore, LSD-induced functional connectivity measures between the thalamus and the right fusiform gyrus and insula correlated significantly with subjective auditory and visual drug effects. Hallucinogenic drug effects might be provoked by facilitations of cortical excitability via thalamocortical interactions. Our findings have implications for the understanding of the mechanism of action of hallucinogenic drugs and provide further insight into the role of the 5-HT 2A -receptor in altered states of consciousness. © 2017 The Authors Acta Psychiatrica Scandinavica Published by John Wiley & Sons Ltd.

Activity alterations in the bed nucleus of the stria terminalis and amygdala during threat anticipation in generalized anxiety disorder.

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Buff, Christine; Brinkmann, Leonie; Bruchmann, Maximilian; Becker, Michael P I; Tupak, Sara; Herrmann, Martin J; Straube, Thomas

2017-11-01

Sustained anticipatory anxiety is central to Generalized Anxiety Disorder (GAD). During anticipatory anxiety, phasic threat responding appears to be mediated by the amygdala, while sustained threat responding seems related to the bed nucleus of the stria terminalis (BNST). Although sustained anticipatory anxiety in GAD patients was proposed to be associated with BNST activity alterations, firm evidence is lacking. We aimed to explore temporal characteristics of BNST and amygdala activity during threat anticipation in GAD patients. Nineteen GAD patients and nineteen healthy controls (HC) underwent functional magnetic resonance imaging (fMRI) during a temporally unpredictable threat anticipation paradigm. We defined phasic and a systematic variation of sustained response models for blood oxygen level-dependent responses during threat anticipation, to disentangle temporally dissociable involvement of the BNST and the amygdala. GAD patients relative to HC responded with increased phasic amygdala activity to onset of threat anticipation and with elevated sustained BNST activity that was delayed relative to the onset of threat anticipation. Both the amygdala and the BNST displayed altered responses during threat anticipation in GAD patients, albeit with different time courses. The results for the BNST activation hint towards its role in sustained threat responding, and contribute to a deeper understanding of pathological sustained anticipatory anxiety in GAD. © The Author (2017). Published by Oxford University Press.

Surgical management of thalamic gliomas: case selection, technical considerations, and review of literature.

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Sai Kiran, Narayanam Anantha; Thakar, Sumit; Dadlani, Ravi; Mohan, Dilip; Furtado, Sunil Valentine; Ghosal, Nandita; Aryan, Saritha; Hegde, Alangar S

2013-07-01

This study aimed to identify (1) the thalamic gliomas suitable for surgical resection and (2) the appropriate surgical approach based on their location and the displacement of the posterior limb of the internal capsule (PLIC). A retrospective study over a 5-year period (from 2006 to 2010) was performed in 41 patients with thalamic gliomas. The mean age of these patients was 20.4 years (range, 2-65 years). Twenty (49 %) tumors were thalamic, 19 (46 %) were thalamopeduncular, and 2 (5 %) were bilateral. The PLIC, based on T2-weighted magnetic resonance axial sections, was displaced anterolaterally in 23 (56 %) cases and laterally in 6 (14 %) cases. It was involved by lesion in eight (20 %) cases and could not be identified in four (10 %) cases. Resection, favored in patients with well-defined, contrast-enhancing lesions, was performed in 34 (83 %) cases, while a biopsy was resorted to in 7 (17 %) cases. A gross total resection or near total resection (>90 %) could be achieved in 26 (63 %) cases. The middle temporal gyrus approach, used when the PLIC was displaced anterolaterally, was the commonly used approach (63.5 %). Common pathologies were pilocytic astrocytoma (58 %) in children and grade III/IV astrocytomas (86 %) in adults. Preoperative motor deficits improved in 64 % of the patients with pilocytic lesions as compared to 0 % in patients with grade III/IV lesions (P value, 0.001). Postoperatively, two patients (5 %) had marginal worsening of motor power, two patients developed visual field defects, and one patient developed a third nerve paresis. Radical resection of thalamic gliomas is a useful treatment modality in a select subset of patients and is the treatment of choice for pilocytic astrocytomas. Tailoring the surgical approach, depending on the relative position of the PLIC, has an important bearing on outcome.

Photoproduction of lepton pairs in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies

Energy Technology Data Exchange (ETDEWEB)

Moreira, B. D.; Goncalves, V. P.; De Santana Amaral, J. T. [Universidade Federal de Pelotas, Instituto de Fisica e Matematica (Brazil)

2013-03-25

In this contribution we study coherent interactions as a probe of the nonlinear effects in the Quantum Electrodynamics (QED). In particular, we study the multiphoton effects in the production of leptons pairs for proton-nucleus and nucleus-nucleus collisions for heavy nuclei. In the proton-nucleus we assume the ultrarelativistic proton as a source of photons and estimate the photoproduction of lepton pairs on nuclei at RHIC and LHC energies considering the multiphoton effects associated to multiple rescattering of the projectile photon on the proton of the nucleus. In nucleus - nucleus colllisions we consider the two nuclei as a source of photons. As each scattering contributes with a factor {alpha}Z to the cross section, this contribution must be taken into account for heavy nuclei. We consider the Coulomb corrections to calculate themultiple scatterings and estimate the total cross section for muon and tau pair production in proton-nucleus and nucleus-nucleus collisions at RHIC and LHC energies.

Model for nucleus-nucleus, hadron-nucleus and hadron-proton multiplicity distributions

International Nuclear Information System (INIS)

Singh, C.P.; Shyam, M.; Tuli, S.K.

1986-07-01

A model relating hadron-proton, hadron-nucleus and nucleus-nucleus multiplicity distributions is proposed and some interesting consequences are derived. The values of the parameters are the same for all the processes and are given by the QCD hypothesis of ''universal'' hadronic multiplicities which are found to be asymptotically independent of target and beam in hadronic and current induced reactions in particle physics. (author)

Interactions between thalamic and cortical rhythms during semantic memory recall in human

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Slotnick, Scott D.; Moo, Lauren R.; Kraut, Michael A.; Lesser, Ronald P.; Hart, John, Jr.

2002-04-01

Human scalp electroencephalographic rhythms, indicative of cortical population synchrony, have long been posited to reflect cognitive processing. Although numerous studies employing simultaneous thalamic and cortical electrode recording in nonhuman animals have explored the role of the thalamus in the modulation of cortical rhythms, direct evidence for thalamocortical modulation in human has not, to our knowledge, been obtained. We simultaneously recorded from thalamic and scalp electrodes in one human during performance of a cognitive task and found a spatially widespread, phase-locked, low-frequency rhythm (7-8 Hz) power decrease at thalamus and scalp during semantic memory recall. This low-frequency rhythm power decrease was followed by a spatially specific, phase-locked, fast-rhythm (21-34 Hz) power increase at thalamus and occipital scalp. Such a pattern of thalamocortical activity reflects a plausible neural mechanism underlying semantic memory recall that may underlie other cognitive processes as well.

Higgs-boson production in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Anon.

1992-01-01

Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider

Higgs-Boson Production in Nucleus-Nucleus Collisions

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Norbury, John W.

1992-01-01

Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

The correlation of the thalamic lesions on MRI with cerebral cortical blood flow in patients with lacunar infarction

International Nuclear Information System (INIS)

Nabatame, Hidehiko; Nakamura, Kazuo; Matsuda, Minoru; Fujimoto, Naoki; Fukuyama, Hidenao.

1995-01-01

We performed MRI and measured cerebral blood flow (CBF) using 123 I-IMP SPECT microsphere model in twenty three right-handed patients with lacunar infarction. Twelve of 23 patients showed chronic deterioration of dysarthria and gait disturbance. The mental function of the patients was evaluated by the Mini-Mental State (MMS) examination. The area of high intensity on T2-weighted images was quantitatively analyzed in the cerebral white matter (WM), lenticular nucleus (LN) and thalamus (THA). The score of MMS was positively correlated with the local CBF in the bilateral frontal, parietal, temporal and occipital cortices (p<0.05). Also, the area of high intensity in the left THA showed a significant negative correlation with local CBF of the bilateral frontal, parietal, temporal and occipital cortices (p<0.001). The high intensity areas of the bilateral LN, right WM and right THA had a significant but weaker negative correlation with local CBF of some cortices. These findings suggest that thalamic lesions on the dominant side play an important role in the reduction of cortical blood flow and the deterioration of mental functions in patients with lacunar infarction. (author)

Neurochemical pathways that converge on thalamic trigeminovascular neurons: potential substrate for modulation of migraine by sleep, food intake, stress and anxiety.

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Rodrigo Noseda

Full Text Available Dynamic thalamic regulation of sensory signals allows the cortex to adjust better to rapidly changing behavioral, physiological and environmental demands. To fulfill this role, thalamic neurons must themselves be subjected to constantly changing modulatory inputs that originate in multiple neurochemical pathways involved in autonomic, affective and cognitive functions. Our overall goal is to define an anatomical framework for conceptualizing how a 'decision' is made on whether a trigeminovascular thalamic neuron fires, for how long, and at what frequency. To begin answering this question, we determine which neuropeptides/neurotransmitters are in a position to modulate thalamic trigeminovascular neurons. Using a combination of in-vivo single-unit recording, juxtacellular labeling with tetramethylrhodamine dextran (TMR and in-vitro immunohistochemistry, we found that thalamic trigeminovascular neurons were surrounded by high density of axons containing biomarkers of glutamate, GABA, dopamine and serotonin; moderate density of axons containing noradrenaline and histamine; low density of axons containing orexin and melanin concentrating hormone (MCH; but not axons containing CGRP, serotonin 1D receptor, oxytocin or vasopressin. In the context of migraine, the findings suggest that the transmission of headache-related nociceptive signals from the thalamus to the cortex may be modulated by opposing forces (i.e., facilitatory, inhibitory that are governed by continuous adjustments needed to keep physiological, behavioral, cognitive and emotional homeostasis.

Decreased regional cerebral blood flow in the bilateral thalami and medulla oblongata determined by an easy Z-score (eZIS) analysis of (99m)Tc-ECD-SPECT images in a case of MM2-thalamic-type sporadic Creutzfeldt-Jakob disease.

Science.gov (United States)

Hayashi, Yuichi; Iwasaki, Yasushi; Yoshikura, Nobuaki; Asano, Takahiko; Hatano, Taku; Tatsumi, Shinsui; Satoh, Katsuya; Kimura, Akio; Kitamoto, Tetsuyuki; Yoshida, Mari; Inuzuka, Takashi

2015-11-15

We report a case of autopsy-verified MM2-thalamic-type sporadic Creutzfeldt-Jakob disease (sCJD) in a 46-year-old patient with a 16-month history of abnormal behavior, progressive dementia, insomnia, and speech disturbances without family history. Neurological examination revealed progressive dementia, frontal signs, insomnia, speech disturbance, gait disturbance and bilaterally exaggerated tendon reflexes. Both brain MRI and cerebrospinal fluid examinations, including 14-3-3 protein, yielded normal results. An easy Z-score (eZIS) analysis for (99m)Tc-ethyl cysteinate dimer-single photon emission computed tomography ((99m)Tc-ECD-SPECT) revealed decreased regional cerebral blood flow in the bilateral thalami and medulla oblongata. PRNP gene analysis revealed methionine homozygosity at codon 129 without mutation. Neuropathological examinations revealed severe neuronal loss, gliosis, and hypertrophic astrocytosis in the medial thalamus and inferior olivary nucleus. A slight depletion of Purkinje cells was observed. PrP immunostaining showed no obvious PrP deposits in the basal ganglia, thalamus, cerebellum, or brainstem; however, mild synaptic-type PrP deposits with some smaller plaque-like structures were only partially observed in the localized region of the frontal lobe with the spongiform change. Western blot analyses of protease-resistant PrP showed a type 2 pattern. In conclusion, eZIS analysis of (99m)Tc-ECD-SPECT images is useful for detecting both thalamic and medullary lesions. This is the first case of medullary lesions detected in a live patient with MM2-thalamic-type sCJD using SPECT. Copyright © 2015 Elsevier B.V. All rights reserved.

Angular momentum and incident-energy dependence of nucleus-nucleus interaction

International Nuclear Information System (INIS)

Yamaguchi, S.

1991-01-01

The purpose of this paper is to understand intuitively the origin of the angular momentum and incident-energy dependence of the nucleus-nucleus interaction on the basis of the totally- antisymmetrized many-body theory. With the aim of understanding the structure of the nucleus-nucleus interaction, we show first that the nucleus-nucleus interaction can be written by the use of the density-distribution function and the phase-space distribution function instead of using the many-body wave function itself. And we show that the structure change of the density-distribution function with the increase of the angular momentum causes the angular momentum dependence of the nucleus-nucleus interaction and that the incident-energy dependence of the nucleus-nucleus interaction originates from the structure change of the phase-space distribution function

Thalamic, brainstem, and cerebellar glucose metabolism in the hemiplegic monkey

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Shimoyama, I.; Dauth, G.W.; Gilman, S.; Frey, K.A.; Penney, J.B. Jr.

1988-12-01

Unilateral ablation of cerebral cortical areas 4 and 6 of Brodmann in the macaque monkey results in a contralateral hemiplegia that resolves partially with time. During the phase of dense hemiplegia, local cerebral metabolic rate for glucose (1CMRG1c) is decreased significantly in most of the thalamic nuclei ipsilateral to the ablation, and there are slight contralateral decreases. The lCMRGlc is reduced bilaterally in most of the brainstem nuclei and bilaterally in the deep cerebellar nuclei, but only in the contralateral cerebellar cortex. During the phase of partial motor recovery, lCMRGlc is incompletely restored in many of the thalamic nuclei ipsilateral to the ablation and completely restored in the contralateral nuclei. In the brainstem and deep cerebellar nuclei, poor to moderate recovery occurs bilaterally. Moderate recovery occurs in the contralateral cerebellar cortex. The findings demonstrate that a unilateral cerebral cortical lesion strongly affects lCMRGlc in the thalamus ipsilaterally and in the cerebellar cortex contralaterally, but in the brainstem bilaterally. Partial recovery of lCMRGlc accompanies the progressive motor recovery. The structures affected include those with direct, and also those with indirect, connections to the areas ablated.

New results on nuclear multifragmentation in nucleon-nucleus and nucleus-nucleus collisions at relativistic energies

International Nuclear Information System (INIS)

Besliu, Calin; Jipa, Alexandru; Iliescu, Bogdan; Felea, Daniel

2002-01-01

Some new aspects on the multifragmentation processes in nucleus-nucleus and nucleon-nucleus collisions at high energies are discussed in this work. Experimental data obtained in international collaborations (for example, MULTI Collaboration with KEK Tsukuba (Japan) and SKM 200 Collaboration with JINR Dubna (Russia)) are used to discuss new mechanisms in the target nucleus fragmentation. Correlations with stopping power, participant region size and energy density are included. Comparisons of the experimental results with the predictions of a phenomenological geometric model of intermediate mass fragment multiplicity, caloric curves and angular distributions are also presented. These results are used for global description of the multifragmentation processes in nucleon-nucleus and nucleus-nucleus collisions at relativistic energies. The size of the participant region and the average intermediate mass fragments multiplicity are taken into consideration using the free space probability. A few correlations between the deposited energy in the participant region and stability state of the intermediate mass fragments are presented in this work. The importance of the collision geometry in the multifragmentation processes is stressed. The results suggest different time moments for the incident nucleus fragmentation and for the target nucleus fragmentation. The associated entropies are distinct. (authors)

Emerging Role for Corticotropin Releasing Factor Signaling in the Bed Nucleus of the Stria Terminalis at the Intersection of Stress and Reward

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Yuval eSilberman

2013-05-01

Full Text Available Stress and anxiety play an important role in the development and maintanence of drug and alcohol addiction. The bed nucleus of the stria terminalis (BNST, a brain region involved in the production of long-term stress related behaviors, plays an important role in animal models of relapse, such as reinstatement to previously extinguished drug-seeking behaviors. While a number of neurotransmitter systems have been suggested to play a role in these behaviors, recent evidence points to the neuropeptide corticotropin releasing factor (CRF as being critically important in BNST mediated reinstatement behaviors. The BNST is a complex brain region with multiple afferent and efferent systems and a variety of cell types and there has only been limited work trying to understand how CRF modulates this complex neuronal system. Recent work from our lab and others have begun to unravel these BNST neurocircuits and explore their roles in CRF-related reinstatement behaviors. This review will examine the role of BNST CRF signaling in drug addiction and reinstatment with an emphasis on critical neurocircuitry within the BNST that may offer new insights into treatments for addiction.

Emerging role for corticotropin releasing factor signaling in the bed nucleus of the stria terminalis at the intersection of stress and reward.

Science.gov (United States)

Silberman, Yuval; Winder, Danny G

2013-01-01

Stress and anxiety play an important role in the development and maintenance of drug and alcohol addiction. The bed nucleus of the stria terminalis (BNST), a brain region involved in the production of long-term stress-related behaviors, plays an important role in animal models of relapse, such as reinstatement to previously extinguished drug-seeking behaviors. While a number of neurotransmitter systems have been suggested to play a role in these behaviors, recent evidence points to the neuropeptide corticotropin releasing factor (CRF) as being critically important in BNST-mediated reinstatement behaviors. Although numerous studies indicate that the BNST is a complex brain region with multiple afferent and efferent systems and a variety of cell types, there has only been limited work to determine how CRF modulates this complex neuronal system at the circuit level. Recent work from our lab and others have begun to unravel these BNST neurocircuits and explore their roles in CRF-related reinstatement behaviors. This review will examine the role of CRF signaling in drug addiction and reinstatement with an emphasis on critical neurocircuitry within the BNST that may offer new insights into treatments for addiction.

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

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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.

Thalamic hemorrhage following carotid angioplasty and stenting

International Nuclear Information System (INIS)

Friedman, Jonathan A.; Kallmes, David F.; Wijdicks, Eelco F.M.

2004-01-01

Carotid angioplasty and stenting (CAS) has emerged as an alternative treatment of carotid stenosis for patients poorly suited for endarterectomy. Intracerebral hemorrhage following carotid revascularization is rare and thought to be related to hyperperfusion injury in most cases. Early experience suggests an increased incidence of hemorrhage following CAS as compared to endarterectomy. We describe a patient who suffered a thalamic hemorrhage following CAS. Because this hemorrhage occurred in a vascular territory unlikely to have been supplied by the treated artery, this case suggests that the mechanism of intracerebral hemorrhage following CAS may in some cases be different from the hyperperfusion hemorrhage classically described following endarterectomy. (orig.)

Disrupted Auto-Activation, Dysexecutive and Confabulating Syndrome Following Bilateral Thalamic and Right Putaminal Stroke

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Lieve De Witte

2008-01-01

Full Text Available Objective: Clinical, neuropsychological, structural and functional neuroimaging results are reported in a patient who developed a unique combination of symptoms after a bi-thalamic and right putaminal stroke. The symptoms consisted of dysexecutive disturbances associated with confabulating behavior and auto-activation deficits. Background: Basal ganglia and thalamic lesions may result in a variety of motor, sensory, neuropsychological and behavioral syndromes. However, the combination of a dysexecutive syndrome complicated at the behavioral level with an auto-activation and confabulatory syndrome has never been reported. Methods: Besides clinical and neuroradiological investigations, an extensive set of standardized neuropsychological tests was carried out. Results: In the post-acute phase of the stroke, a dysexecutive syndrome was found in association with confabulating behavior and auto-activation deficits. MRI showed focal destruction of both thalami and the right putamen. Quantified ECD SPECT revealed bilateral hypoperfusions in the basal ganglia and thalamus but no perfusion deficits were found at the cortical level. Conclusion: The combination of disrupted auto-activation, dysexecutive and confabulating syndrome in a single patient following isolated subcortical damage renders this case exceptional. Although these findings do not reveal a functional disruption of the striato-ventral pallidal-thalamic-frontomesial limbic circuitry, they add to the understanding of the functional role of the basal ganglia in cognitive and behavioral syndromes.

Connections of the medial posterior parietal cortex (area 7m) in the monkey.

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Leichnetz, G R

2001-06-01

The afferent and efferent cortical and subcortical connections of the medial posterior parietal cortex (area 7m) were studied in cebus (Cebus apella) and macaque (Macaca fascicularis) monkeys using the retrograde and anterograde capabilities of the horseradish peroxidase (HRP) technique. The principal intraparietal corticocortical connections of area 7m in both cebus and macaque cases were with the ipsilateral medial bank of the intraparietal sulcus (MIP) and adjacent superior parietal lobule (area 5), inferior parietal lobule (area 7a), lateral bank of the IPS (area 7ip), caudal parietal operculum (PGop), dorsal bank of the caudal superior temporal sulcus (visual area MST), and medial prestriate cortex (including visual area PO and caudal medial lobule). Its principal frontal corticocortical connections were with the prefrontal cortex in the shoulder above the principal sulcus and the cortex in the shoulder above the superior ramus of the arcuate sulcus (SAS), the area purported to contain the smooth eye movement-related frontal eye field (FEFsem) in the cebus monkey by other investigators. There were moderate connections with the cortex in the rostral bank of the arcuate sulcus (purported to contain the saccade-related frontal eye field; FEFsac), supplementary eye field (SEF), and rostral dorsal premotor area (PMDr). Area 7m also had major connections with the cingulate cortex (area 23), particularly the ventral bank of the cingulate sulcus. The principal subcortical connections of area 7m were with the dorsal portion of the ventrolateral thalamic (VLc) nucleus, lateral posterior thalamic nucleus, lateral pulvinar, caudal mediodorsal thalamic nucleus and medial pulvinar, central lateral, central superior lateral, and central inferior intralaminar thalamic nuclei, dorsolateral caudate nucleus and putamen, middle region of the claustrum, nucleus of the diagonal band, zona incerta, pregeniculate nucleus, anterior and posterior pretectal nuclei, intermediate layer of

Pontine and Thalamic Influences on Fluid Rewards: I. Operant Responding for Sucrose and Corn Oil

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Liang, Nu-Chu; Freet, Christopher S.; Grigson, Patricia S; Norgren, Ralph

2011-01-01

The reward strength of orosensory sucrose and corn oil was measured using fixed and progressive ratio operant schedules. Because the orosensory effects of the stimuli were of interest, Experiment 1 compared operant responses for sucrose in sham and real feeding rats. The results demonstrated that rats would work for sucrose solutions without the accompanying postingestive effects. Furthermore, the break points for high concentrations of sucrose (1.0 M or 2.0 M) were significantly higher in sham feeding rats than in real feeding controls. Experiment 2 investigated the role of the parabrachial nucleus (PBN) and of the thalamic orosensory area (TOA) in sucrose and corn oil reward. During free access, rats with PBN lesions (PBNx) licked significantly less sucrose solution than their controls, but both groups ingested a similar volume of corn oil emulsion. When an operant was imposed, these same PBNx rats failed to respond for sucrose and continued only modestly for corn oil. In contrast, the TOA lesioned rats (TOAx) showed no impairment in responding for sucrose or corn oil during either the free access or operant sessions. Furthermore, rats with TOA lesions demonstrated significantly higher break points for sucrose than did their controls. Together, the data imply that the PBN but not the TOA is critical for the perception of, or responding to the reward value of sucrose and corn oil. PMID:21703290

Bilateral thalamic stroke due to occlusion of the artery of Percheron in a patient with patent foramen ovale: a case report

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López-Serna Raúl

2009-09-01

Full Text Available Abstract Introduction Bilateral thalamic infarcts are rare presentations of stroke. They are the result of a complex combination of risk factors and a predisposing vessel distribution. The artery of Percheron, characterized by a single arterial trunk that irrigates both paramedian thalamic regions, can be occluded as a result of embolic diseases leading to bilateral paramedian thalamic infarcts. Clinical and image findings of this uncommon form of posterior circulation infarct are presented along with their anatomic and pathophysiologic correlates. Case presentation A 27-year-old Mexican man with no relevant medical history was admitted to hospital after he was found deeply stuporous. On admission, an urgent neuroimaging protocol for stroke, including magnetic resonance imaging and magnetic resonance imaging angiography, was performed. The scans revealed symmetric bilateral hyperintense paramedian thalamic lesions consistent with acute ischemic events. The posterior circulation was patent including the tip of the basilar artery and both posterior cerebral arteries, making the case compatible with occlusion of the artery of Percheron. Further evaluation with an aim to define the etiology revealed a patent foramen ovale as the cause of embolism. Conclusion Bilateral thalamic infarcts are unusual presentations of posterior circulation stroke; once they are diagnosed by an adequate neuroimaging protocol, a further evaluation to define the cause is necessary. Cardioembolism should always be considered in relatively young patients. A complete evaluation should be conducted by an interdisciplinary team including neurologists, cardiologists and neurosurgeons.

Schizophrenia-Related Microdeletion Impairs Emotional Memory through MicroRNA-Dependent Disruption of Thalamic Inputs to the Amygdala

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Tae-Yeon Eom

2017-05-01

Full Text Available Individuals with 22q11.2 deletion syndrome (22q11DS are at high risk of developing psychiatric diseases such as schizophrenia. Individuals with 22q11DS and schizophrenia are impaired in emotional memory, anticipating, recalling, and assigning a correct context to emotions. The neuronal circuits responsible for these emotional memory deficits are unknown. Here, we show that 22q11DS mouse models have disrupted synaptic transmission at thalamic inputs to the lateral amygdala (thalamo-LA projections. This synaptic deficit is caused by haploinsufficiency of the 22q11DS gene Dgcr8, which is involved in microRNA processing, and is mediated by the increased dopamine receptor Drd2 levels in the thalamus and by reduced probability of glutamate release from thalamic inputs. This deficit in thalamo-LA synaptic transmission is sufficient to cause fear memory deficits. Our results suggest that dysregulation of the Dgcr8–Drd2 mechanism at thalamic inputs to the amygdala underlies emotional memory deficits in 22q11DS.

Schizophrenia-Related Microdeletion Impairs Emotional Memory through MicroRNA-Dependent Disruption of Thalamic Inputs to the Amygdala.

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Eom, Tae-Yeon; Bayazitov, Ildar T; Anderson, Kara; Yu, Jing; Zakharenko, Stanislav S

2017-05-23

Individuals with 22q11.2 deletion syndrome (22q11DS) are at high risk of developing psychiatric diseases such as schizophrenia. Individuals with 22q11DS and schizophrenia are impaired in emotional memory, anticipating, recalling, and assigning a correct context to emotions. The neuronal circuits responsible for these emotional memory deficits are unknown. Here, we show that 22q11DS mouse models have disrupted synaptic transmission at thalamic inputs to the lateral amygdala (thalamo-LA projections). This synaptic deficit is caused by haploinsufficiency of the 22q11DS gene Dgcr8, which is involved in microRNA processing, and is mediated by the increased dopamine receptor Drd2 levels in the thalamus and by reduced probability of glutamate release from thalamic inputs. This deficit in thalamo-LA synaptic transmission is sufficient to cause fear memory deficits. Our results suggest that dysregulation of the Dgcr8-Drd2 mechanism at thalamic inputs to the amygdala underlies emotional memory deficits in 22q11DS. Copyright © 2017 The Author(s). Published by Elsevier Inc. All rights reserved.

COMMUNICATION Designing a somatosensory neural prosthesis: percepts evoked by different patterns of thalamic stimulation

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Heming, Ethan; Sanden, Andrew; Kiss, Zelma H. T.

2010-12-01

Although major advances have been made in the development of motor prostheses, fine motor control requires intuitive somatosensory feedback. Here we explored whether a thalamic site for a somatosensory neural prosthetic could provide natural somatic sensation to humans. Different patterns of electrical stimulation (obtained from thalamic spike trains) were applied in patients undergoing deep brain stimulation surgery. Changes in pattern produced different sensations, while preserving somatotopic representation. While most percepts were reported as 'unnatural', some stimulations produced more 'natural' sensations than others. However, the additional patterns did not elicit more 'natural' percepts than high-frequency (333 Hz) electrical stimulation. These features suggest that despite some limitations, the thalamus may be a feasible site for a somatosensory neural prosthesis and different stimulation patterns may be useful in its development.

Deconfinement of quarks and gluons in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Gorenstein, M.I.

2011-01-01

The energy dependence of hadron production in relativistic nucleus-nucleus collisions reveals the anomalies. They were predicted as the signals of the deconfinement phase transition and observed by NA49 collaboration in Pb+Pb collisions at the CERN SPS. This indicates the onset of the deconfinement in central nucleus-nucleus collisions at about 30 AGeV.

Distinct phasic and sustained brain responses and connectivity of amygdala and bed nucleus of the stria terminalis during threat anticipation in panic disorder.

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Brinkmann, L; Buff, C; Feldker, K; Tupak, S V; Becker, M P I; Herrmann, M J; Straube, T

2017-11-01

Panic disorder (PD) patients are constantly concerned about future panic attacks and exhibit general hypersensitivity to unpredictable threat. We aimed to reveal phasic and sustained brain responses and functional connectivity of the amygdala and the bed nucleus of the stria terminalis (BNST) during threat anticipation in PD. Using functional magnetic resonance imaging (fMRI), we investigated 17 PD patients and 19 healthy controls (HC) during anticipation of temporally unpredictable aversive and neutral sounds. We used a phasic and sustained analysis model to disentangle temporally dissociable brain activations. PD patients compared with HC showed phasic amygdala and sustained BNST responses during anticipation of aversive v. neutral stimuli. Furthermore, increased phasic activation was observed in anterior cingulate cortex (ACC), insula and prefrontal cortex (PFC). Insula and PFC also showed sustained activation. Functional connectivity analyses revealed partly distinct phasic and sustained networks. We demonstrate a role for the BNST during unpredictable threat anticipation in PD and provide first evidence for dissociation between phasic amygdala and sustained BNST activation and their functional connectivity. In line with a hypersensitivity to uncertainty in PD, our results suggest time-dependent involvement of brain regions related to fear and anxiety.

Long-term outcome of thalamic deep brain stimulation in two patients with Tourette syndrome.

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Ackermans, Linda; Duits, Annelien; Temel, Yasin; Winogrodzka, Ania; Peeters, Frenk; Beuls, Emile A M; Visser-Vandewalle, Veerle

2010-10-01

Thalamic deep brain stimulation for intractable Tourette Syndrome was introduced in 1999 by Vandewalle et al. In this follow-up study, the authors report on the long-term (6 and 10 years) outcome in terms of tic reduction, cognition, mood and side effects of medial thalamic deep brain stimulation in two previously described Tourette patients. The authors compared the outcome of two patients at 6 and 10 years after surgery with their preoperative status and after 8 months and 5 years of treatment, respectively. Standardised video recordings were scored by three independent investigators. Both patients underwent (neuro)psychological assessment at all time points of follow-up. Tic improvement observed at 5 years in patient 1 (90.1%) was maintained at 10 years (92.6%). In patient 2, the tic improvement at 8 months (82%) was slightly decreased at 6 years (78%). During follow-up, case 1 revealed no changes in cognition, but case 2 showed a decrease in verbal fluency and learning which was in line with his subjective reports. Case 2 showed a slight decrease in depression, but overall psychopathology was still high at 6 years after surgery with an increase in anger and aggression together with difficulties in social adaptation. Besides temporary hardware-related complications, no distressing adverse effects were observed. Bilateral thalamic stimulation may provide sustained tic benefit after at least 6 years, but to maximise overall outcome, attention is needed for postoperative psychosocial adaptation, already prior to surgery.

Oxytocin induces penile erection and yawning when injected into the bed nucleus of the stria terminalis: Involvement of glutamic acid, dopamine, and nitric oxide.

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Sanna, Fabrizio; Bratzu, Jessica; Argiolas, Antonio; Melis, Maria Rosaria

2017-11-01

Oxytocin (5-100ng), but not Arg 8 -vasopressin (100ng), injected unilaterally into the bed nucleus of the stria terminalis (BNST) induces penile erection and yawning in a dose-dependent manner in male rats. The minimal effective dose was 20ng for penile erection and 5ng for yawning. Oxytocin responses were abolished not only by the oxytocin receptor antagonist d(CH 2 ) 5 Tyr(Me) 2 -Orn 8 -vasotocin (1μg), but also by (+) MK-801 (1μg), an excitatory amino acid receptor antagonist of the N-methyl-d-aspartic acid (NMDA) subtype, SCH 23390 (1μg), a D1 receptor antagonist, but not haloperidol (1μg), a D2 receptor antagonist, and SMTC (40μg), an inhibitor of neuronal nitric oxide synthase, injected into the BNST 15min before oxytocin. Oxytocin-induced penile erection, but not yawning, was also abolished by CNQX (1μg), an excitatory amino acid receptor antagonist of the AMPA subtype. In contrast, oxytocin responses were not reduced by bicuculline (20ng), a GABA A receptor antagonist, phaclofen (5μg), a GABA B receptor antagonist, CP 376395, a CRF receptor-1 antagonist (5μg), or astressin 2B, a CRF receptor-2 antagonist (150ng). Considering the ability of NMDA (100ng) to induce penile erection and yawning when injected into the BNST and the available evidence showing possible interaction among oxytocin, glutamic acid, and dopamine in the BNST, oxytocin possibly activates glutamatergic neurotransmission in the BNST. This in turn leads to the activation of neural pathways projecting back to the paraventricular nucleus, medial preoptic area, ventral tegmental area, and/or ventral subiculum/amygdala, thereby inducing penile erection and yawning. Copyright © 2017 Elsevier Inc. All rights reserved.

Clinical appraisal of stereotactic hematoma aspiration surgery for hypertensive thalamic hemorrhage

International Nuclear Information System (INIS)

Sasaki, Koji; Matsumoto, Keizo

1992-01-01

Three hundred and four patients with hypertensive thalamic hemorrhage were managed by medical treatment, ventricular drainage, or CT-controlled stereotactic aspiration surgery (AS). The therapeutic results of the 6-month outcome were analyzed and correlated with the volume of the hematoma. A hematoma volume of 20 ml was thought to be the critical size in determining whether the outcome would be favorable or unfavorable. Indications for AS are suggested as follows. In patients with a small-sized hematoma having a volume of less than 10 ml use of AS should be restricted to patients with severe paralysis or other neurological complications and the elderly (aged 70 years or older). For patients with a medium-sized hematoma having a volume between 10 ml and 20 ml, AS is indicated for patients having severe paralysis and disturbances of consciousness. For patients with a large-sized hematoma having a volume of 20 ml or more, AS increases not only the survival rate of patients but also reduces the number of bedridden patients. We conclude that AS opens up a new avenue of surgical treatment for hypertensive thalamic hemorrhage, which has been no indication for hematoma evacuation by conventional craniotomy. (author)

Reduction in nerve root compression by the nucleus pulposus after Feng's Spinal Manipulation☆

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Feng, Yu; Gao, Yan; Yang, Wendong; Feng, Tianyou

2013-01-01

Ninety-four patients with lumbar intervertebral disc herniation were enrolled in this study. Of these, 48 were treated with Feng's Spinal Manipulation, hot fomentation, and bed rest (treatment group). The remaining 46 patients were treated with hot fomentation and bed rest only (control group). After 3 weeks of treatment, clinical parameters including the angle of straight-leg raising, visual analogue scale pain score, and Japanese Orthopaedic Association score for low back pain were improved. The treatment group had significantly better improvement in scores than the control group. Magnetic resonance myelography three-dimensional reconstruction imaging of the vertebral canal demonstrated that filling of the compressed nerve root sleeve with cerebrospinal fluid increased significantly in the treatment group. The diameter of the nerve root sleeve was significantly larger in the treatment group than in the control group. However, the sagittal diameter index of the herniated nucleus pulposus and the angle between the nerve root sleeve and the thecal sac did not change significantly in either the treatment or control groups. The effectiveness of Feng's Spinal Manipulation for the treatment of symptoms associated with lumbar intervertebral disc herniation may be attributable to the relief of nerve root compression, without affecting the herniated nucleus pulposus or changing the morphology or position of the nerve root. PMID:25206408

Short-term Synaptic Depression in the Feedforward Inhibitory Circuit in the Dorsal Lateral Geniculate Nucleus.

Science.gov (United States)

Augustinaite, Sigita; Heggelund, Paul

2018-05-24

Synaptic short-term plasticity (STP) regulates synaptic transmission in an activity-dependent manner and thereby has important roles in the signal processing in the brain. In some synapses, a presynaptic train of action potentials elicits post-synaptic potentials that gradually increase during the train (facilitation), but in other synapses, these potentials gradually decrease (depression). We studied STP in neurons in the visual thalamic relay, the dorsal lateral geniculate nucleus (dLGN). The dLGN contains two types of neurons: excitatory thalamocortical (TC) neurons, which transfer signals from retinal afferents to visual cortex, and local inhibitory interneurons, which form an inhibitory feedforward loop that regulates the thalamocortical signal transmission. The overall STP in the retino-thalamic relay is short-term depression, but the distinct kind and characteristics of the plasticity at the different types of synapses are unknown. We studied STP in the excitatory responses of interneurons to stimulation of retinal afferents, in the inhibitory responses of TC neurons to stimulation of afferents from interneurons, and in the disynaptic inhibitory responses of TC neurons to stimulation of retinal afferents. Moreover, we studied STP at the direct excitatory input to TC neurons from retinal afferents. The STP at all types of the synapses showed short-term depression. This depression can accentuate rapid changes in the stream of signals and thereby promote detectability of significant features in the sensory input. In vision, detection of edges and contours is essential for object perception, and the synaptic short-term depression in the early visual pathway provides important contributions to this detection process. Copyright © 2018 IBRO. Published by Elsevier Ltd. All rights reserved.

Disruption of Accumbens and Thalamic White Matter Connectivity Revealed by Diffusion Tensor Tractography in Young Men with Genetic Risk for Obesity

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Gaia Olivo

2018-02-01

Full Text Available Background: Neurovascular coupling is associated with white matter (WM structural integrity, and it is regulated by specific subtypes of dopaminergic receptors. An altered activity of such receptors, highly expressed in reward-related regions, has been reported in carriers of obesity-risk alleles of the fat mass and obesity associated (FTO gene. Among the reward-related regions, the thalamus and the nucleus accumbens are particularly vulnerable to blood pressure dysregulation due to their peculiar anatomo-vascular characteristics, and have been consistently reported to be altered in early-stage obesity. We have thus hypothesized that a disruption in thalamus and nucleus accumbens WM microstructure, possibly on neurovascular basis, could potentially be a predisposing factor underlying the enhanced risk for obesity in the risk-allele carriers.Methods: We have tested WM integrity in 21 male participants genotyped on the FTO risk single nucleotide polymorphisms (SNP rs9939609, through a deterministic tractography analysis. Only homozygous participants (9 AA, 12 TT were included. 11 tracts were selected and categorized as following according to our hypothesis: “risk tracts”, “obesity-associated tracts”, and a control tract (forcpes major. We investigated whether an association existed between genotype, body mass index (BMI and WM microstructural integrity in the “risk-tracts” (anterior thalamic radiation and accumbofrontal fasciculus compared to other tracts. Moreover, we explored whether WM diffusivity could be related to specific personality traits in terms of punishment and reward sensitivity, as measure by the BIS/BAS questionnaire.Results: An effect of the genotype and an interaction effect of genotype and BMI were detected on the fractional anisotropy (FA of the “risk tracts”. Correlations between WM diffusivity parameters and measures of punishment and reward sensitivity were also detected in many WM tracts of both networks

Persistence of disturbed thalamic glucose metabolism in a case of Wernicke-Korsakoff syndrome.

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Fellgiebel, Andreas; Scheurich, Armin; Siessmeier, Thomas; Schmidt, Lutz G; Bartenstein, Peter

2003-10-30

We report the case of a 40-year-old alcoholic male patient, hospitalized with an acute ataxia of stance and gait, ocular muscle weakness with nystagmus and a global apathetic-confusional state. After admission, an amnestic syndrome with confabulation was also observed and diagnosis of Wernicke-Korsakoff syndrome was made. Under treatment with intravenous thiamine, the patient recovered completely from gaze weakness and ataxia, whereas a severe amnestic syndrome persisted. Fluorodeoxyglucose (FDG) positron emission tomography (PET) showed bilateral thalamic and severe bilateral temporal-parietal hypometabolism resembling a pattern typical for Alzheimer's disease. Longitudinal assessment of the alcohol-abstinent and thiamine-substituted patient revealed improvements of clinical state and neuropsychological performance that were paralleled by recovered cerebral glucose metabolism. In contrast to metabolic rates that increased between 7.1% (anterior cingulate, left) and 23.5% (parietal, left) in cortical areas during a 9-month remission period, thalamic glucose metabolism remained severely disturbed over time (change: left +0.2%, right +0.3%).

Localization and function of the cannabinoid CB1 receptor in the anterolateral bed nucleus of the stria terminalis.

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Nagore Puente

Full Text Available BACKGROUND: The bed nucleus of the stria terminalis (BNST is involved in behaviors related to natural reward, drug addiction and stress. In spite of the emerging role of the endogenous cannabinoid (eCB system in these behaviors, little is known about the anatomy and function of this system in the anterolateral BNST (alBNST. The aim of this study was to provide a detailed morphological characterization of the localization of the cannabinoid 1 (CB1 receptor a necessary step toward a better understanding of the physiological roles of the eCB system in this region of the brain. METHODOLOGY/PRINCIPAL FINDINGS: We have combined anatomical approaches at the confocal and electron microscopy level to ex-vivo electrophysiological techniques. Here, we report that CB1 is localized on presynaptic membranes of about 55% of immunopositive synaptic terminals for the vesicular glutamate transporter 1 (vGluT1, which contain abundant spherical, clear synaptic vesicles and make asymmetrical synapses with alBNST neurons. About 64% of vGluT1 immunonegative synaptic terminals show CB1 immunolabeling. Furthermore, 30% and 35% of presynaptic boutons localize CB1 in alBNST of conditional mutant mice lacking CB1 mainly from GABAergic neurons (GABA-CB1-KO mice and mainly from cortical glutamatergic neurons (Glu-CB1-KO mice, respectively. Extracellular field recordings and whole cell patch clamp in the alBNST rat brain slice preparation revealed that activation of CB1 strongly inhibits excitatory and inhibitory synaptic transmission. CONCLUSIONS/SIGNIFICANCE: This study supports the anterolateral BNST as a potential neuronal substrate of the effects of cannabinoids on stress-related behaviors.

The neurobiology of thalamic amnesia: Contributions of medial thalamus and prefrontal cortex to delayed conditional discrimination.

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Mair, Robert G; Miller, Rikki L A; Wormwood, Benjamin A; Francoeur, Miranda J; Onos, Kristen D; Gibson, Brett M

2015-07-01

Although medial thalamus is well established as a site of pathology associated with global amnesia, there is uncertainty about which structures are critical and how they affect memory function. Evidence from human and animal research suggests that damage to the mammillothalamic tract and the anterior, mediodorsal (MD), midline (M), and intralaminar (IL) nuclei contribute to different signs of thalamic amnesia. Here we focus on MD and the adjacent M and IL nuclei, structures identified in animal studies as critical nodes in prefrontal cortex (PFC)-related pathways that are necessary for delayed conditional discrimination. Recordings of PFC neurons in rats performing a dynamic delayed non-matching-to position (DNMTP) task revealed discrete populations encoding information related to planning, execution, and outcome of DNMTP-related actions and delay-related activity signaling previous reinforcement. Parallel studies recording the activity of MD and IL neurons and examining the effects of unilateral thalamic inactivation on the responses of PFC neurons demonstrated a close coupling of central thalamic and PFC neurons responding to diverse aspects of DNMTP and provide evidence that thalamus interacts with PFC neurons to give rise to complex goal-directed behavior exemplified by the DNMTP task. Copyright © 2015 Elsevier Ltd. All rights reserved.

Spatiotemporal profiles of receptive fields of neurons in the lateral posterior nucleus of the cat LP-pulvinar complex.

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Piché, Marilyse; Thomas, Sébastien; Casanova, Christian

2015-10-01

The pulvinar is the largest extrageniculate thalamic visual nucleus in mammals. It establishes reciprocal connections with virtually all visual cortexes and likely plays a role in transthalamic cortico-cortical communication. In cats, the lateral posterior nucleus (LP) of the LP-pulvinar complex can be subdivided in two subregions, the lateral (LPl) and medial (LPm) parts, which receive a predominant input from the striate cortex and the superior colliculus, respectively. Here, we revisit the receptive field structure of LPl and LPm cells in anesthetized cats by determining their first-order spatiotemporal profiles through reverse correlation analysis following sparse noise stimulation. Our data reveal the existence of previously unidentified receptive field profiles in the LP nucleus both in space and time domains. While some cells responded to only one stimulus polarity, the majority of neurons had receptive fields comprised of bright and dark responsive subfields. For these neurons, dark subfields' size was larger than that of bright subfields. A variety of receptive field spatial organization types were identified, ranging from totally overlapped to segregated bright and dark subfields. In the time domain, a large spectrum of activity overlap was found, from cells with temporally coinciding subfield activity to neurons with distinct, time-dissociated subfield peak activity windows. We also found LP neurons with space-time inseparable receptive fields and neurons with multiple activity periods. Finally, a substantial degree of homology was found between LPl and LPm first-order receptive field spatiotemporal profiles, suggesting a high integration of cortical and subcortical inputs within the LP-pulvinar complex. Copyright © 2015 the American Physiological Society.

Study of Hadron Production in Hadron-Nucleus and Nucleus-Nucleus Collisions at the CERN SPS

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Klochkov, V; Herve, A E; Kowalski, S; Kaptur, E A; Kowalik, K L; Dominik, W M; Matulewicz, T N; Krasnoperov, A; Feofilov, G; Vinogradov, L; Kovalenko, V; Johnson, S R; Planeta, R J; Rubbia, A; Marton, K; Messerly, B A; Puzovic, J; Bogomilov, M V; Bravar, A; Renfordt, R A E; Deveaux, M; Engel, R R; Grzeszczuk, A; Davis, N; Kuich, M; Lyubushkin, V; Kondratev, V; Kadija, K; Diakonos, F; Slodkowski, M A; Rauch, W H; Pistillo, C; Laszlo, A; Nakadaira, T; Hasegawa, T; Sadovskiy, A; Morozov, S; Petukhov, O; Mathes, H; Roehrich, D; Marcinek, A J; Marino, A D; Grebieszkow, K; Di luise, S; Wlodarczyk, Z; Rybczynski, M A; Wojtaszek-szwarc, A; Nirkko, M C; Sakashita, K; Golubeva, M; Kurepin, A; Manic, D; Kolev, D I; Kisiel, J E; Koziel, M E; Rondio, E; Larsen, D T; Czopowicz, T R; Seyboth, P; Turko, L; Guber, F; Marin, V; Busygina, O; Strikhanov, M; Taranenko, A; Cirkovic, M; Roth, M A; Pulawski, S M; Aduszkiewicz, A M; Bunyatov, S; Vechernin, V; Nagai, Y; Anticic, T; Dynowski, K M; Mackowiak-pawlowska, M K; Stefanek, G; Pavin, M; Fodor, Z P; Nishikawa, K; Tada, M; Blondel, A P P; Stroebele, H W; Posiadala, M Z; Kolesnikov, V; Andronov, E; Zimmerman, E D; Antoniou, N; Majka, Z; Dumarchez, J; Naskret, M; Ivashkin, A; Tsenov, R V; Koziel, M G; Schmidt, K J; Melkumov, G; Popov, B; Panagiotou, A; Richter-was, E M; Morgala, S J; Paolone, V; Damyanova, A; Gazdzicki, M; Unger, M T; Wilczek, A G; Stepaniak, J M; Seryakov, A; Susa, T; Staszel, P P; Brzychczyk, J; Maksiak, B; Tefelski, D B

2007-01-01

The NA61/SHINE (SHINE = SPS Heavy Ion and Neutrino Experiment) experiment is a large acceptance hadron spectrometer at the CERN SPS for the study of the hadronic final states produced in interactions of various beam particles (pions, protons, C, S and In) with a variety of fixed targets at the SPS energies. The main components of the current detector were constructed and used by the NA49 experiment. The physics program of NA61/SHINE consists of three main subjects. In the first stage of data taking (2007-2009) measurements of hadron production in hadron-nucleus interactions needed for neutrino (T2K) and cosmic-ray (Pierre Auger and KASCADE) experiments will be performed. In the second stage (2009-2011) hadron production in proton-proton and proton-nucleus interactions needed as reference data for a better understanding of nucleus-nucleus reactions will be studied. In the third stage (2009-2013) energy dependence of hadron production properties will be measured in nucleus-nucleus collisions as well as in p+p a...

How Human Amygdala and Bed Nucleus of the Stria Terminalis May Drive Distinct Defensive Responses.

Science.gov (United States)

Klumpers, Floris; Kroes, Marijn C W; Baas, Johanna M P; Fernández, Guillén

2017-10-04

The ability to adaptively regulate responses to the proximity of potential danger is critical to survival and imbalance in this system may contribute to psychopathology. The bed nucleus of the stria terminalis (BNST) is implicated in defensive responding during uncertain threat anticipation whereas the amygdala may drive responding upon more acute danger. This functional dissociation between the BNST and amygdala is however controversial, and human evidence scarce. Here we used data from two independent functional magnetic resonance imaging studies [ n = 108 males and n = 70 (45 females)] to probe how coordination between the BNST and amygdala may regulate responses during shock anticipation and actual shock confrontation. In a subset of participants from Sample 2 ( n = 48) we demonstrate that anticipation and confrontation evoke bradycardic and tachycardic responses, respectively. Further, we show that in each sample when going from shock anticipation to the moment of shock confrontation neural activity shifted from a region anatomically consistent with the BNST toward the amygdala. Comparisons of functional connectivity during threat processing showed overlapping yet also consistently divergent functional connectivity profiles for the BNST and amygdala. Finally, childhood maltreatment levels predicted amygdala, but not BNST, hyperactivity during shock anticipation. Our results support an evolutionary conserved, defensive distance-dependent dynamic balance between BNST and amygdala activity. Shifts in this balance may enable shifts in defensive reactions via the demonstrated differential functional connectivity. Our results indicate that early life stress may tip the neural balance toward acute threat responding and via that route predispose for affective disorder. SIGNIFICANCE STATEMENT Previously proposed differential contributions of the BNST and amygdala to fear and anxiety have been recently debated. Despite the significance of understanding their

Pion production in nucleus--nucleus collisions

International Nuclear Information System (INIS)

Schroeder, L.S.

1975-06-01

Current work on pion production in high-energy nucleus-nucleus collisions is reviewed. The majority of existing data are of the inclusive variety in which a single final state pion is detected. Experimental data are compared and their possible contributions to obtaining new information on nuclear structure is discussed. Various models which attempt to explain the observed single-inclusive-pion spectra either on the basis of a nucleon-nucleus interaction in which Fermi motion is included or on some type of cooperative model are examined. Other areas of interest involving pion production include tests of charge symmetry and pion multiplicities. (9 figures, 1 table) (U.S.)

Perspective of ultrarelativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Specht, H.J.

1985-01-01

The paper concerns the lectures given at the International School of nuclear physics, Erice, 1985, which survey the expectations for the field of ultrarelativistic nucleus-nucleus collisions. The primary motivation for the field, the organization of the lectures, and a description of the NA 34 experiment, are all briefly given. (U.K.)

Formation of light particles in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Zagrebaev, V.; Penionzhkevich, Yu.

1993-01-01

The principal experimental results on the yield of the light charged particles in nucleus-nucleus collisions at the low and intermediate energies are reviewed. Inclusive spectra of light particles and their coincidences with the characteristic KX-rays, γ-rays, neutrons, projectile-like fragments, other light particles, fission fragments, and evaporation residues are analyzed. The main theoretical models used for the description of the light particle formation are briefly outlined together with their merits and shortcomings. The unsolved problems of fast light particle formation, in particular, and of nucleus-nucleus interaction dynamics, on the whole, are discussed with the outlooks of new experiments able to clear up some of these problems. (author) 144 refs., 40 figs., 2 tabs

Global features of nucleus-nucleus collisions in ultrarelativistic domain

International Nuclear Information System (INIS)

Savina, M.V.; Shmatov, S.V.; Slavin, N.V.; Zarubin, P.I.

1998-01-01

HIJING generator simulation of nucleus-nucleus collisions at ultrarelativistic energies is presented. It is shown that the global characteristics of nucleus-nucleus collisions, such as distribution of a charged multiplicity, total and electromagnetic transverse energy over pseudorapidity are rather sensitive to some predictions of models of high-exited nuclear medium formation, namely parton energy losses in dense nuclear matter. These losses result in appearance of a broad maximum in global variable distributions over pseudorapidity. The most profound of this effect occurs at central heavy ion collisions at LHC energy

Scaling phenomenon in relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Wong, C.Y.; Blankenbecler, R.

1980-01-01

New scaling variables for proton and pion production in relativistic nucleus-nucleus collisions are introduced which are the generalizations of the Feynmann scaling variable. They allow a simple description of the cross sections at forward and backward angles. 2 figures

Nucleus--nucleus potential

International Nuclear Information System (INIS)

Jaqaman, H.R.

1977-01-01

The nucleus--nucleus interaction is studied within the framework of the generator coordinate method that permits an easy incorporation of the full effects of antisymmetrization. It is found that the interaction, as far as the elastic scattering problem is concerned, can be described by a simple effective potential that is equivalent to the original many-body (and hence non-local) problem. The potential is obtained by dividing the wavefunction into a long-range part and a short-range part and requiring the former to satisfy a Schroedinger equation. This enables avoiding dealing with the troublesome short-range part of the wavefunction and provides a direct link with the optical model so that the potential obtained here is equivalent to the real part of the optical potential (the imaginary part is not investigated). The effective potential is found to consist of three parts: an interaction term between the nucleons belonging to different nuclei, a kinetic energy term due to the change in the intrinsic kinetic energy of the system as a result of the antisymmetrization, and finally an l-dependent part. The kinetic energy term is found to be very repulsive and effectively gives a hard core, and is calculated for the α--α and 16 O-- 16 O cases. The full potential is calculated for the α--α case for the S, D, and G partial waves and then used to calculate the corresponding phase shifts that are then compared with experimental results and other microscopic calculations. Finally, some recent results and analyses of fusion and deep inelastic reactions are reviewed that seem to indicate the presence of a hard core in the nucleus--nucleus potential. Such a hard core is present in the potential obtained in the sudden approximation

Hadron-nucleus collisions

International Nuclear Information System (INIS)

Strugalski, Z.

1981-01-01

Qualitative picture of high energy hadron-nucleus collision process, emerging from the analysis of experimental data, is presented. Appropriate description procedure giving a possibility of reproducing various characteristics of this process in terms of the data on elementary hadron-nucleon interaction is proposed. Formula reproducing hadron-nucleus collision cross sections is derived. Inelastic collision cross sections for pion-nucleus and proton-nucleus reactions at wide energy interval are calculated for Pb, Ag, and Al targets. A-dependence of cross sections for pion-nucleus and proton-nucleus collisions at nearly 50 GeV/c momentum were calculated and compared with existing experimental data. Energy dependence of cross sections for hadron-nucleus collisions is determined simply by energy dependence of corresponding cross sections for hadron-nucleon collisions; A-dependence is determined simply by nuclear sizes and nucleon density distributions in nuclei

Practical CT classification for thalamic hemorrhage. Relationship between localization of hematoma and prognosis

Energy Technology Data Exchange (ETDEWEB)

Kurita, Hiroki; Furuya, Kazuhide; Segawa, Hiromu; Taniguchi, Tamiki; Sano, Keiji [Fuji Brain Inst. and Hospital, Shizuoka (Japan); Shiokawa, Yoshiaki

1994-06-01

The study was designed to establish CT classification for predicting prognosis of thalamic hemorrhage. A retrospective analysis was made on CT scans from 100 patients with hypertensive thalamic hemorrhage less than 4 cm. Four lines were drawn on axial CT scans at the level of the pineal body: (A) line between the lateral edge of the anterior horn and the midpoint of the third ventricle; (B) vertebral line to the sagittal line from the midpoint of the third ventricle; (C) line between the lateral edge of the trigone and the midpoint of the third ventricle; and (D) line between the lateral edge of the anterior horn and the lateral edge of the trigone. According to the lateral extension, the location of hematoma fell into three types: anterior type in which the center of hematoma was located between lines A and B (type A); posterior type in which the center of hematoma was located between lines B and C and external margin of hematoma was localized medial to line D (type P); postero-lateral type in which the center of hematoma was located between lines B and C and showed lateral extension beyond line D (type PL). Severe hemiparesis was observed in 15.3% for type A, 21.8% for type P, and 59.3% for type PL. Good prognosis was seen in 84.7% for type A, 70.9% for type P, and 12.5% for type PL. Acute disturbance of consciousness was significantly observed in patients with medial extension of hematoma (86.4%) as compared with those without it (21.4%). These results indicated that CT classification is a simple means for predicting functional outcome of motor paresis and consciousness disturbance in patients with thalamic hemorrhage. (N.K.).

Practical CT classification for thalamic hemorrhage. Relationship between localization of hematoma and prognosis

International Nuclear Information System (INIS)

Kurita, Hiroki; Furuya, Kazuhide; Segawa, Hiromu; Taniguchi, Tamiki; Sano, Keiji; Shiokawa, Yoshiaki.

1994-01-01

The study was designed to establish CT classification for predicting prognosis of thalamic hemorrhage. A retrospective analysis was made on CT scans from 100 patients with hypertensive thalamic hemorrhage less than 4 cm. Four lines were drawn on axial CT scans at the level of the pineal body: (A) line between the lateral edge of the anterior horn and the midpoint of the third ventricle; (B) vertebral line to the sagittal line from the midpoint of the third ventricle; (C) line between the lateral edge of the trigone and the midpoint of the third ventricle; and (D) line between the lateral edge of the anterior horn and the lateral edge of the trigone. According to the lateral extension, the location of hematoma fell into three types: anterior type in which the center of hematoma was located between lines A and B (type A); posterior type in which the center of hematoma was located between lines B and C and external margin of hematoma was localized medial to line D (type P); postero-lateral type in which the center of hematoma was located between lines B and C and showed lateral extension beyond line D (type PL). Severe hemiparesis was observed in 15.3% for type A, 21.8% for type P, and 59.3% for type PL. Good prognosis was seen in 84.7% for type A, 70.9% for type P, and 12.5% for type PL. Acute disturbance of consciousness was significantly observed in patients with medial extension of hematoma (86.4%) as compared with those without it (21.4%). These results indicated that CT classification is a simple means for predicting functional outcome of motor paresis and consciousness disturbance in patients with thalamic hemorrhage. (N.K.)

The deep stimulation of the sub-thalamus nucleus affects the limbic and associative circuits: a study in {sup 18}F-F.D.G. -PET in the Parkinson disease;La stimulation profonde du noyau sous thalamique affecte les circuits limbique et associatif: une etude en 18FDG-TEP dans la maladie de Parkinson

Energy Technology Data Exchange (ETDEWEB)

Le Jeune, F.; Garin, E. [Centre Eugene-Marquis, Servive de medecine nucleaire, 35 - Rennes (France); Le Jeune, F.; Peron, J.; Grandjean, D.; Drapier, S.; Haegelen, C.; Garin, E.; Millet, B.; Verin, M. [Universite de Rennes-1, URU comportement et noyaux gris centraux, 35 - Rennes (France); Peron, J.; Drapier, S.; Haegelen, C.; Verin, M. [CHU Pontchaillou, service de neurologie, 35 - Rennes (France); Grandjean, D. [University of Genova, Swiss Center for Affective Sciences, Geneve (Switzerland); Millet, B. [Centre hospitalier Guillaume-Regnier, service de psychiatrie adulte, 35 - Rennes (France)

2010-05-15

The purpose of this study is to highlight the changes in brain metabolism in {sup 18}F.D.G.-PET to improve understanding of the non-motor functional role .This study confirms the non-motor functional role of the sub thalamic nucleus (S.T.N.) in limbic and associative circuits in humans.These results provide working hypotheses to study the correlations between neuropsychological alterations clinically diagnosed and cerebral metabolism in order to identify the neural circuits involved. (N.C.)

Association of Thalamic Dysconnectivity and Conversion to Psychosis in Youth and Young Adults at Elevated Clinical Risk

Science.gov (United States)

Anticevic, Alan; Haut, Kristen; Murray, John D.; Repovs, Grega; Yang, Genevieve J.; Diehl, Caroline; McEwen, Sarah C.; Bearden, Carrie E.; Addington, Jean; Goodyear, Bradley; Cadenhead, Kristin S.; Mirzakhanian, Heline; Cornblatt, Barbara A.; Olvet, Doreen; Mathalon, Daniel H.; McGlashan, Thomas H.; Perkins, Diana O.; Belger, Aysenil; Seidman, Larry J.; Tsuang, Ming T.; van Erp, Theo G. M.; Walker, Elaine F; Hamann, Stephan; Woods, Scott W; Qiu, Maolin; Cannon, Tyrone D.

2016-01-01

IMPORTANCE Severe neuropsychiatric conditions, such as schizophrenia, affect distributed neural computations. One candidate system profoundly altered in chronic schizophrenia involves the thalamocortical networks. It is widely acknowledged that schizophrenia is a neurodevelopmental disorder that likely affects the brain before onset of clinical symptoms. However, no investigation has tested whether thalamocortical connectivity is altered in individuals at risk for psychosis or whether this pattern is more severe in individuals who later develop full-blown illness. OBJECTIVES To determine whether baseline thalamocortical connectivity differs between individuals at clinical high risk for psychosis and healthy controls, whether this pattern is more severe in those who later convert to full-blown illness, and whether magnitude of thalamocortical dysconnectivity is associated with baseline prodromal symptom severity. DESIGN, SETTING, AND PARTICIPANTS In this multicenter, 2-year follow-up, case-control study, we examined 397 participants aged 12–35 years of age (243 individuals at clinical high risk of psychosis, of whom 21 converted to full-blown illness, and 154 healthy controls). The baseline scan dates were January 15, 2010, to April 30, 2012. MAIN OUTCOMES AND MEASURES Whole-brain thalamic functional connectivity maps were generated using individuals’ anatomically defined thalamic seeds, measured using resting-state functional connectivity magnetic resonance imaging. RESULTS Using baseline magnetic resonance images, we identified thalamocortical dysconnectivity in the 243 individuals at clinical high risk for psychosis, which was particularly pronounced in the 21 participants who converted to full-blown illness. The pattern involved widespread hypoconnectivity between the thalamus and prefrontal and cerebellar areas, which was more prominent in those who converted to full-blown illness (t173 = 3.77, P < .001, Hedge g = 0.88). Conversely, there was marked

Physiological and Morphological Characterization of Organotypic Cocultures of the Chick Forebrain Area MNH and its Main Input Area DMA/DMP

OpenAIRE

Endepols, Heike; Jungnickel, Julia; Braun, Katharina

2001-01-01

Cocultures of the learning-relevant forebrain region mediorostrai neostriatum and hyperstriatum ventrale (MNH) and its main glutamatergic input area nucleus dorsomedialis anterior thalami/posterior thalami were morphologically and physiologically characterized. Synaptic contacts of thalamic fibers were lightand electron-microscopically detected on MNH neurons by applying the fluorescence tracer DiI-C18(3) into the thalamus part of the coculture. Most thalamic syn...

The imaginary part of the nucleus - nucleus optical potential

International Nuclear Information System (INIS)

Phatak, S.C.; Sinha, B.

1978-01-01

The contribution to the imaginary nucleus - nucleus optical potential has been estimated by evaluating the energy - conserving seocond-order term in the perturbation series. The incoming nuclear field is supposed to excite nucleons in a nucleus in this calculation and the nuclear excitations are approximated by particle-hole excitations in a Fermi gas. The resulting imaginary potential compares favourably with phenomenological potentials. (author)

VGLUT1 or VGLUT2 mRNA-positive neurons in spinal trigeminal nucleus provide collateral projections to both the thalamus and the parabrachial nucleus in rats.

Science.gov (United States)

Zhang, Chun-Kui; Li, Zhi-Hong; Qiao, Yu; Zhang, Ting; Lu, Ya-Cheng; Chen, Tao; Dong, Yu-Lin; Li, Yun-Qing; Li, Jin-Lian

2018-04-12

The trigemino-thalamic (T-T) and trigemino-parabrachial (T-P) pathways are strongly implicated in the sensory-discriminative and affective/emotional aspects of orofacial pain, respectively. These T-T and T-P projection fibers originate from the spinal trigeminal nucleus (Vsp). We previously determined that many vesicular glutamate transporter (VGLUT1 and/or VGLUT2) mRNA-positive neurons were distributed in the Vsp of the adult rat, and most of these neurons sent their axons to the thalamus or cerebellum. However, whether VGLUT1 or VGLUT2 mRNA-positive projection neurons exist that send their axons to both the thalamus and the parabrachial nucleus (PBN) has not been reported. Thus, in the present study, dual retrograde tract tracing was used in combination with fluorescence in situ hybridization (FISH) for VGLUT1 or VGLUT2 mRNA to identify the existence of VGLUT1 or VGLUT2 mRNA neurons that send collateral projections to both the thalamus and the PBN. Neurons in the Vsp that send collateral projections to both the thalamus and the PBN were mainly VGLUT2 mRNA-positive, with a proportion of 90.3%, 93.0% and 85.4% in the oral (Vo), interpolar (Vi) and caudal (Vc) subnucleus of the Vsp, respectively. Moreover, approximately 34.0% of the collateral projection neurons in the Vc showed Fos immunopositivity after injection of formalin into the lip, and parts of calcitonin gene-related peptide (CGRP)-immunopositive axonal varicosities were in direct contact with the Vc collateral projection neurons. These results indicate that most collateral projection neurons in the Vsp, particularly in the Vc, which express mainly VGLUT2, may relay orofacial nociceptive information directly to the thalamus and PBN via axon collaterals.

Ascending control of arousal and motivation: role of nucleus incertus and its peptide neuromodulators in behavioural responses to stress.

Science.gov (United States)

Ma, S; Gundlach, A L

2015-06-01

Arousal is a process that involves the activation of ascending neural pathways originating in the rostral pons that project to the forebrain through the midbrain reticular formation to promote the activation of key cortical, thalamic, hypothalamic and limbic centres. Established modulators of arousal include the cholinergic, serotonergic, noradrenergic and dopaminergic networks originating in the pons and midbrain. Recent data indicate that a population of largely GABAergic projection neurones located in the nucleus incertus (NI) are also involved in arousal and motivational processes. The NI has prominent efferent connections with distinct hypothalamic, amygdalar and thalamic nuclei, in addition to dense projections to key brain regions associated with the generation and pacing of hippocampal activity. The NI receives strong inputs from the prefrontal cortex, lateral habenula and the interpeduncular and median raphe nuclei, suggesting it is highly integrated in circuits regulating higher cognitive behaviours (hippocampal theta rhythm) and emotion. Anatomical and functional studies have revealed that the NI is a rich source of multiple peptide neuromodulators, including relaxin-3, and may mediate extra-hypothalamic effects of the stress hormone corticotrophin-releasing factor, as well as other key modulators such as orexins and oxytocin. This review provides an overview of earlier studies and highlights more recent research that implicates this neural network in the integration of arousal and motivated behaviours and has begun to identify the associated mechanisms. Future research that should help to better clarify the connectivity and function of the NI in major experimental species and humans is also discussed. © 2015 British Society for Neuroendocrinology.

Multicentre European study of thalamic stimulation for parkinsonian tremor: a 6 year follow-up

NARCIS (Netherlands)

Hariz, M. I.; Krack, P.; Alesch, F.; Augustinsson, L.-E.; Bosch, A.; Ekberg, R.; Johansson, F.; Johnels, B.; Meyerson, B. A.; N'Guyen, J.-P.; Pinter, M.; Pollak, P.; von Raison, F.; Rehncrona, S.; Speelman, J. D.; Sydow, O.; Benabid, A.-L.

2008-01-01

To evaluate the results of ventral intermediate (Vim) thalamic deep brain stimulation (DBS) in patients with tremor predominant Parkinson's disease (PD) at 6 years post surgery. This was a prolonged follow-up study of 38 patients from eight centres who participated in a multicentre study, the 1 year

Involvement of the oxytocin system in the bed nucleus of the stria terminalis in the sex-specific regulation of social recognition

Science.gov (United States)

Dumais, Kelly M.; Alonso, Andrea G.; Immormino, Marisa A.; Bredewold, Remco; Veenema, Alexa H.

2015-01-01

Sex differences in the oxytocin (OT) system in the brain may explain why OT often regulates social behaviors in sex-specific ways. However, a link between sex differences in the OT system and sex-specific regulation of social behavior has not been tested. Here, we determined whether sex differences in the OT receptor (OTR) or in OT release in the posterior bed nucleus of the stria terminalis (pBNST) mediates sex-specific regulation of social recognition in rats. We recently showed that, compared to female rats, male rats have a three-fold higher OTR binding density in the pBNST, a sexually dimorphic area implicated in the regulation of social behaviors. We now demonstrate that OTR antagonist (5 ng/0.5 μl/side) administration into the pBNST impairs social recognition in both sexes, while OT (100 pg/0.5 μl/side) administration into the pBNST prolongs the duration of social recognition in males only. These effects seem specific to social recognition, as neither treatment altered total social investigation time in either sex. Moreover, baseline OT release in the pBNST, as measured with in vivo microdialysis, did not differ between the sexes. However, males showed higher OT release in the pBNST during social recognition compared to females. These findings suggest a sex-specific role of the OT system in the pBNST in the regulation of social recognition. PMID:26630388

Involvement of the oxytocin system in the bed nucleus of the stria terminalis in the sex-specific regulation of social recognition.

Science.gov (United States)

Dumais, Kelly M; Alonso, Andrea G; Immormino, Marisa A; Bredewold, Remco; Veenema, Alexa H

2016-02-01

Sex differences in the oxytocin (OT) system in the brain may explain why OT often regulates social behaviors in sex-specific ways. However, a link between sex differences in the OT system and sex-specific regulation of social behavior has not been tested. Here, we determined whether sex differences in the OT receptor (OTR) or in OT release in the posterior bed nucleus of the stria terminalis (pBNST) mediates sex-specific regulation of social recognition in rats. We recently showed that, compared to female rats, male rats have a three-fold higher OTR binding density in the pBNST, a sexually dimorphic area implicated in the regulation of social behaviors. We now demonstrate that OTR antagonist (5 ng/0.5 μl/side) administration into the pBNST impairs social recognition in both sexes, while OT (100 pg/0.5 μl/side) administration into the pBNST prolongs the duration of social recognition in males only. These effects seem specific to social recognition, as neither treatment altered total social investigation time in either sex. Moreover, baseline OT release in the pBNST, as measured with in vivo microdialysis, did not differ between the sexes. However, males showed higher OT release in the pBNST during social recognition compared to females. These findings suggest a sex-specific role of the OT system in the pBNST in the regulation of social recognition. Copyright © 2015 Elsevier Ltd. All rights reserved.

Thalamic metabolic alterations with cognitive dysfunction in idiopathic trigeminal neuralgia: a multivoxel spectroscopy study

Energy Technology Data Exchange (ETDEWEB)

Wang, Yuan; Bao, Faxiu; Ma, Shaohui; Guo, Chenguang; Jin, Chenwang; Zhang, Ming [First Affiliated Hospital of Xi' an Jiaotong University, Department of Medical Imaging, Xi' an, Shaanxi (China); Li, Dan [First Affiliated Hospital of Xi' an Jiaotong University, Department of Respiratory and Critical Care Medicine, Xi' an, Shaanxi (China)

2014-08-15

Although abnormalities in metabolite compositions in the thalamus are well described in patients with idiopathic trigeminal neuralgia (ITN), differences in distinct thalamic subregions have not been measured with proton magnetic resonance spectroscopy ({sup 1}H-MRS), and whether there are correlations between thalamic metabolites and cognitive function still remain unknown. Multivoxel MRS was recorded to investigate the metabolic alterations in the thalamic subregions of patients with ITN. The regions of interest were localized in the anterior thalamus (A-Th), intralaminar portion of the thalamus (IL-Th), posterior lateral thalamus (PL-Th), posterior medial thalamus (PM-Th), and medial and lateral pulvinar of the thalamus (PuM-Th and PuL-Th). The N-acetylaspartate to creatine (NAA/Cr) and choline to creatine (Cho/Cr) ratios were measured in the ITN and control groups. Scores of the visual analogue scale (VAS) and the Montreal Cognitive Assessment (MoCA) were analyzed to correlate with the neuroradiological findings. The NAA/Cr ratio in the affected side of PM-Th and PL-Th in ITN patients was statistically lower than that in the corresponding regions of the thalamus in controls. The NAA/Cr ratio in the affected PM-Th was negatively associated with VAS and disease duration. Furthermore, decreases of NAA/Cr and Cho/Cr were detected in the affected side of IL-Th, and lower Cho/Cr was positively correlated with MoCA values in the ITN group. Our result of low level of NAA/Cr in the affected PM-Th probably serves as a marker of the pain-rating index, and decreased Cho/Cr in IL-Th may be an indicator of cognitive disorder in patients with ITN. (orig.)

Case of herpes simplex encephalitis(HSE) with a thalamic lesion

Energy Technology Data Exchange (ETDEWEB)

Fujimori, K; Koike, R; Yuasa, T; Miyatake, T; Ito, J

1987-02-01

A case of herpes simplex encephalitis (HSE) with thalamic involvement was reported. The patient, a 27-year-old man, was admitted because of abnormal behavior and fever. He exhibited a disturbance of consciousness, meningial signs, and hyperreflexia. A CT scan of the head revealed diffuse brain edema. Acute encephalitis, especially HSE, was suspected, and so the intravenous administration of acyclovir and steroid therapy were started. The titer of herpes simplex Type 1 virus, as measured by CF and ELISA, was found to have increased amounts of serum and cerebrospinal fluid. 5 days after the onset, his consciousness worsened. He could not tell his name and scarely opened his eyes upon pain stimulation. A CT scan at this time showed low-density lesions in the left thalamus, cingulate gyrus, and the posterior portion of the putamen. About 5 days later, his consciousness level was increased, but he was mute. This symptom was thought to be thalamic aphasia, which might be correlative with the low-density lesions shown in the left thalamus by the CT scan. About 30 days after the onset of the disease, his speech became normal, and a CT scan at 51 hospital days showed no abnormality. The etiology of low-density lesions of the left thalamus in the CT scan is speculated to be as follows: firstly, vascular damage of circulation disturbance, and secondly a special affinity of herpes simplex Type 1 virus to the thalamus.

Multivoxel proton magnetic resonance spectroscopy detects thalamic neurochemical metabolic changes in patients with major depressive disorder

Directory of Open Access Journals (Sweden)

Rania E. Mohamed

2017-06-01

Conclusion: The multi-voxel 1H-MRS can provide an insight to the neurochemical metabolic changes occurring in both thalami in patients with MDD. Increased severity of depression is significantly related to these thalamic neurochemical changes.

Quasi-elastic shadowing in nucleus-nucleus elastic scattering

Energy Technology Data Exchange (ETDEWEB)

Dymarz, R; Malecki, A [Institute of Nuclear Physics, Krakow (Poland); Gluski, K [Institute of Nuclear Research, Warsaw (Poland); Picchi, P [Turin Univ. (Italy). Ist. di Fisica; Consiglio Nazionale delle Ricerche, Turin (Italy). Lab. di Cosmo-Geofisica)

1979-01-06

The complete evaluation of the Glauber multiple-scattering series for nucleus-nucleus collisions is a very difficult task and that is why various approximate formulae were proposed. In this work some of these approximations are discussed.

Molecular phenotyping of transient postnatal tyrosine hydroxylase neurons in the rat bed nucleus of the stria terminalis.

Science.gov (United States)

Carter, David A

2017-07-01

The bed nucleus of the stria terminalis (BNST) is a complex integrative centre in the forebrain, composed of multiple sub-nuclei, each with discrete populations of neurons. Progress in understanding BNST function, both in the adult and during postnatal maturation, is dependent upon a more complete characterization of neuronal phenotypes in the BNST. The aim of the current study was to define the molecular phenotype of one postnatal BNST neuronal population, in order to identify molecular factors that may underlie both (protein marker-related) immaturity, and secondly, the transience of this phenotype. This BNST population was originally identified by high, but transient expression of the EGR1 transcription factor (TF) in postnatal rat lateral intermediate BNST (BNSTLI). The current results confirm a high level of Egr1 activation in postnatal day 10 (PN10) male BNSTLI that is lost at PN40, and now demonstrate a similar pattern of transient activation in female brains. Apparent cellular immaturity in this population, as indicated by low levels of the adult neuronal marker NeuN/RBFOX3, was found to be uncorrelated with both key neuronal regulator protein expression (SOX2 and REST), and also RBFOX2 protein levels. The BNSTLI neurons have a partial catecholaminergic phenotype (tyrosine hydroxylase-positive/dopa decarboxylase-negative; TH+ve/DDC-ve) that is lost at PN40. In contrast, the co-expressed neuropeptide, somatostatin, is maintained, albeit at lower levels, at PN40. The transcriptional basis of the transient and partial catecholaminergic phenotype was investigated by analysing TFs known to maintain adult dopaminergic (TH+ve/DDC+ve) neuronal phenotypes. The BNSTLI neurons were shown to lack forkhead TFs including FOXA1, FOXA2 and FOXO1. In addition, the BNSTLI neurons had low, primarily cytoplasmic, expression of NR4A2/NURR1, an orphan nuclear receptor that is critical for adult maintenance of midbrain dopamine neurons. These results detail the molecular features

Inhibition of NMDARs in the nucleus reticularis of the thalamus produces delta frequency bursting

Directory of Open Access Journals (Sweden)

Yuchun Zhang

2009-11-01

Full Text Available Injection of NMDAR antagonist into the thalamus can produce delta frequency EEG oscillations in the thalamocortical system. It is surprising that an antagonist of an excitatory neurotransmitter should trigger such activity, and the mechanism is unknown. One hypothesis is that the antagonist blocks excitation of GABAergic cells, thus producing disinhibition. To test this hypothesis, we investigated the effect of NMDAR antagonist (APV on cells of the nucleus reticularis (nRT in rat brain slices, a thalamic nucleus that can serve as a pacemaker for thalamocortical delta oscillations and that is composed entirely of GABAergic neurons. We found, unexpectedly, that nRT cells are hyperpolarized by APV. This occurs because these cells have an unusual form of NMDAR (probably NR2C that contributes inward current at resting potential in response to ambient glutamate. The hyperpolarization produced by APV is sufficient to deinactivate T-type calcium channels, and these trigger rhythmic bursting at delta frequency. The APV-induced delta frequency bursting is abolished by dopamine D2 receptor antagonist, indicating that dopamine and NMDAR antagonist work synergistically to stimulate delta frequency bursting. Our results have significant implications concerning the electrophysiological basis of schizophrenia and bring together the NMDAR hypofunction, dopamine, and GABA theories of the disease. Our results suggest that NMDAR hypofunction and dopamine work synergistically on the GABAergic cells of the nRT to generate the delta frequency EEG oscillations, a thalamocortical dysrhythmia (TCD in the awake state that is an established abnormality in schizophrenia.

A case of thalamic hemorrhage presenting high density on CT in a long time

International Nuclear Information System (INIS)

Hosoya, Takaaki; Takeda, Yoshio; Sugai, Yukio; Umetsu, Akemi; Yamaguchi, Koichi

1988-01-01

We presented a thalamic hemorrhage in a 29-year-old woman with idiopathic thrombocytopenic purpura during pregnancy showing a high density lesion at least for 50 days on CT. From beginning of the illness, this condition was considered to continue for 3 months by chronic bleeding or recurrent hemorrhage. (author)

High density QCD and nucleus-nucleus scattering deeply in the saturation region

International Nuclear Information System (INIS)

Kormilitzin, Andrey; Levin, Eugene; Miller, Jeremy S.

2011-01-01

In this paper we solve the equations that describe nucleus-nucleus scattering, in high density QCD, in the framework of the BFKL Pomeron Calculus. We found that (i) the contribution of short distances to the opacity for nucleus-nucleus scattering dies at high energies, (ii) the opacity tends to unity at high energy, and (iii) the main contribution that survives comes from soft (long distance) processes for large values of the impact parameter. The corrections to the opacity Ω(Y,b)=1 were calculated and it turns out that they have a completely different form, namely (1-Ω→exp(-Const√(Y))) than the opacity that stems from the Balitsky-Kovchegov equation, which is (1-Ω→exp(-ConstY 2 )). We reproduce the formula for the nucleus-nucleus cross section that is commonly used in the description of nucleus-nucleus scattering, and there is no reason why it should be correct in the Glauber-Gribov approach.

Thalamic functional connectivity predicts seizure laterality in individual TLE patients: application of a biomarker development strategy.

Science.gov (United States)

Barron, Daniel S; Fox, Peter T; Pardoe, Heath; Lancaster, Jack; Price, Larry R; Blackmon, Karen; Berry, Kristen; Cavazos, Jose E; Kuzniecky, Ruben; Devinsky, Orrin; Thesen, Thomas

2015-01-01

Noninvasive markers of brain function could yield biomarkers in many neurological disorders. Disease models constrained by coordinate-based meta-analysis are likely to increase this yield. Here, we evaluate a thalamic model of temporal lobe epilepsy that we proposed in a coordinate-based meta-analysis and extended in a diffusion tractography study of an independent patient population. Specifically, we evaluated whether thalamic functional connectivity (resting-state fMRI-BOLD) with temporal lobe areas can predict seizure onset laterality, as established with intracranial EEG. Twenty-four lesional and non-lesional temporal lobe epilepsy patients were studied. No significant differences in functional connection strength in patient and control groups were observed with Mann-Whitney Tests (corrected for multiple comparisons). Notwithstanding the lack of group differences, individual patient difference scores (from control mean connection strength) successfully predicted seizure onset zone as shown in ROC curves: discriminant analysis (two-dimensional) predicted seizure onset zone with 85% sensitivity and 91% specificity; logistic regression (four-dimensional) achieved 86% sensitivity and 100% specificity. The strongest markers in both analyses were left thalamo-hippocampal and right thalamo-entorhinal cortex functional connection strength. Thus, this study shows that thalamic functional connections are sensitive and specific markers of seizure onset laterality in individual temporal lobe epilepsy patients. This study also advances an overall strategy for the programmatic development of neuroimaging biomarkers in clinical and genetic populations: a disease model informed by coordinate-based meta-analysis was used to anatomically constrain individual patient analyses.

Thalamic Volume Is Reduced in Cervical and Laryngeal Dystonias.

Science.gov (United States)

Waugh, Jeff L; Kuster, John K; Levenstein, Jacob M; Makris, Nikos; Multhaupt-Buell, Trisha J; Sudarsky, Lewis R; Breiter, Hans C; Sharma, Nutan; Blood, Anne J

2016-01-01

Dystonia, a debilitating movement disorder characterized by abnormal fixed positions and/or twisting postures, is associated with dysfunction of motor control networks. While gross brain lesions can produce secondary dystonias, advanced neuroimaging techniques have been required to identify network abnormalities in primary dystonias. Prior neuroimaging studies have provided valuable insights into the pathophysiology of dystonia, but few directly assessed the gross volume of motor control regions, and to our knowledge, none identified abnormalities common to multiple types of idiopathic focal dystonia. We used two gross volumetric segmentation techniques and one voxelwise volumetric technique (voxel based morphometry, VBM) to compare regional volume between matched healthy controls and patients with idiopathic primary focal dystonia (cervical, n = 17, laryngeal, n = 7). We used (1) automated gross volume measures of eight motor control regions using the FreeSurfer analysis package; (2) blinded, anatomist-supervised manual segmentation of the whole thalamus (also gross volume); and (3) voxel based morphometry, which measures local T1-weighted signal intensity and estimates gray matter density or volume at the level of single voxels, for both whole-brain and thalamus. Using both automated and manual gross volumetry, we found a significant volume decrease only in the thalamus in two focal dystonias. Decreases in whole-thalamic volume were independent of head and brain size, laterality of symptoms, and duration. VBM measures did not differ between dystonia and control groups in any motor control region. Reduced thalamic gross volume, detected in two independent analyses, suggests a common anatomical abnormality in cervical dystonia and spasmodic dysphonia. Defining the structural underpinnings of dystonia may require such complementary approaches.

Thalamic Volume Is Reduced in Cervical and Laryngeal Dystonias.

Directory of Open Access Journals (Sweden)

Jeff L Waugh

Full Text Available Dystonia, a debilitating movement disorder characterized by abnormal fixed positions and/or twisting postures, is associated with dysfunction of motor control networks. While gross brain lesions can produce secondary dystonias, advanced neuroimaging techniques have been required to identify network abnormalities in primary dystonias. Prior neuroimaging studies have provided valuable insights into the pathophysiology of dystonia, but few directly assessed the gross volume of motor control regions, and to our knowledge, none identified abnormalities common to multiple types of idiopathic focal dystonia.We used two gross volumetric segmentation techniques and one voxelwise volumetric technique (voxel based morphometry, VBM to compare regional volume between matched healthy controls and patients with idiopathic primary focal dystonia (cervical, n = 17, laryngeal, n = 7. We used (1 automated gross volume measures of eight motor control regions using the FreeSurfer analysis package; (2 blinded, anatomist-supervised manual segmentation of the whole thalamus (also gross volume; and (3 voxel based morphometry, which measures local T1-weighted signal intensity and estimates gray matter density or volume at the level of single voxels, for both whole-brain and thalamus.Using both automated and manual gross volumetry, we found a significant volume decrease only in the thalamus in two focal dystonias. Decreases in whole-thalamic volume were independent of head and brain size, laterality of symptoms, and duration. VBM measures did not differ between dystonia and control groups in any motor control region.Reduced thalamic gross volume, detected in two independent analyses, suggests a common anatomical abnormality in cervical dystonia and spasmodic dysphonia. Defining the structural underpinnings of dystonia may require such complementary approaches.

Thalamic Volume Is Reduced in Cervical and Laryngeal Dystonias

Science.gov (United States)

Waugh, Jeff L.; Kuster, John K.; Levenstein, Jacob M.; Makris, Nikos; Multhaupt-Buell, Trisha J.; Sudarsky, Lewis R.; Breiter, Hans C.; Sharma, Nutan; Blood, Anne J.

2016-01-01

Background Dystonia, a debilitating movement disorder characterized by abnormal fixed positions and/or twisting postures, is associated with dysfunction of motor control networks. While gross brain lesions can produce secondary dystonias, advanced neuroimaging techniques have been required to identify network abnormalities in primary dystonias. Prior neuroimaging studies have provided valuable insights into the pathophysiology of dystonia, but few directly assessed the gross volume of motor control regions, and to our knowledge, none identified abnormalities common to multiple types of idiopathic focal dystonia. Methods We used two gross volumetric segmentation techniques and one voxelwise volumetric technique (voxel based morphometry, VBM) to compare regional volume between matched healthy controls and patients with idiopathic primary focal dystonia (cervical, n = 17, laryngeal, n = 7). We used (1) automated gross volume measures of eight motor control regions using the FreeSurfer analysis package; (2) blinded, anatomist-supervised manual segmentation of the whole thalamus (also gross volume); and (3) voxel based morphometry, which measures local T1-weighted signal intensity and estimates gray matter density or volume at the level of single voxels, for both whole-brain and thalamus. Results Using both automated and manual gross volumetry, we found a significant volume decrease only in the thalamus in two focal dystonias. Decreases in whole-thalamic volume were independent of head and brain size, laterality of symptoms, and duration. VBM measures did not differ between dystonia and control groups in any motor control region. Conclusions Reduced thalamic gross volume, detected in two independent analyses, suggests a common anatomical abnormality in cervical dystonia and spasmodic dysphonia. Defining the structural underpinnings of dystonia may require such complementary approaches. PMID:27171035

Deep Brain Stimulation of the Dentato-Rubro-Thalamic Tract: Outcomes of Direct Targeting for Tremor.

Science.gov (United States)

Fenoy, Albert J; Schiess, Mya C

2017-07-01

Targeting the dentato-rubro-thalamic tract (DRTt) has been suggested to be efficacious in deep brain stimulation (DBS) for tremor suppression, both in case reports and post-hoc analyses. This prospective observational study sought to analyze outcomes after directly targeting the DRTt in tremor patients. 20 consecutively enrolled intention tremor patients obtained pre-operative MRI with diffusion tensor (dTi) sequences. Mean baseline tremor amplitude based on The Essential Tremor Rating Assessment Scale was recorded. The DRTt was drawn for each individual on StealthViz software (Medtronic) using the dentate nucleus as the seed region and the ipsilateral pre-central gyrus as the end region and then directly targeted during surgery. Intraoperative testing confirmed successful tremor control. Post-operative analysis of electrode position relative to the DRTt was performed, as was post-operative assessment of tremor improvement. The mean age of patients was 66.8 years; mean duration of tremor was 16 years. Mean voltage for the L electrode = 3.4 V; R = 2.6 V. Mean distance from the center of the active electrode contact to the DRTt was 0.9 mm on the L, and 0.8 mm on the R. Improvement in arm tremor amplitude from baseline after DBS was significant (P tremor suppression. Accounting for hardware, software, and model limitations, depiction of the DRTt allows for placement of electrode contacts directly within the fiber tract for modulation despite any anatomical variation, which reproducibly resulted in good tremor control. © 2017 International Neuromodulation Society.

The expression and activity of β-catenin in the thalamus and its projections to the cerebral cortex in the mouse embryo

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Pratt Thomas

2012-02-01

Full Text Available Abstract Background The mammalian thalamus relays sensory information from the periphery to the cerebral cortex for cognitive processing via the thalamocortical tract. The thalamocortical tract forms during embryonic development controlled by mechanisms that are not fully understood. β-catenin is a nuclear and cytosolic protein that transduces signals from secreted signaling molecules to regulate both cell motility via the cytoskeleton and gene expression in the nucleus. In this study we tested whether β-catenin is likely to play a role in thalamocortical connectivity by examining its expression and activity in developing thalamic neurons and their axons. Results At embryonic day (E15.5, the time when thalamocortical axonal projections are forming, we found that the thalamus is a site of particularly high β-catenin mRNA and protein expression. As well as being expressed at high levels in thalamic cell bodies, β-catenin protein is enriched in the axons and growth cones of thalamic axons and its growth cone concentration is sensitive to Netrin-1. Using mice carrying the β-catenin reporter BAT-gal we find high levels of reporter activity in the thalamus. Further, Netrin-1 induces BAT-gal reporter expression and upregulates levels of endogenous transcripts encoding β-actin and L1 proteins in cultured thalamic cells. We found that β-catenin mRNA is enriched in thalamic axons and its 3'UTR is phylogenetically conserved and is able to direct heterologous mRNAs along the thalamic axon, where they can be translated. Conclusion We provide evidence that β-catenin protein is likely to be an important player in thalamocortcial development. It is abundant both in the nucleus and in the growth cones of post-mitotic thalamic cells during the development of thalamocortical connectivity and β-catenin mRNA is targeted to thalamic axons and growth cones where it could potentially be translated. β-catenin is involved in transducing the Netrin-1 signal to

Human Thalamic-Prefrontal Peduncle Connectivity Revealed by Diffusion Spectrum Imaging Fiber Tracking

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Chuanqi Sun

2018-04-01

Full Text Available The thalamic-prefrontal peduncle (TPP is a large bundle connecting the thalamus and prefrontal cortex. The definitive structure and function of the TPP are still controversial. To investigate the connectivity and segmentation patterns of the TPP, we employed diffusion spectrum imaging with generalized q-sampling reconstruction to perform both subject-specific and template-based analyses. Our results confirmed the trajectory and spatial relationship of the TPP in the human brain and identified the connection areas in the prefrontal cortex. The TPP-connecting areas identified based on Brodmann areas (BAs were BAs 8–11 and 45–47. Based on the automated anatomical atlas, these areas were the medial superior frontal gyrus, superior frontal gyrus, middle frontal gyrus, pars triangularis, pars orbitalis, anterior orbital gyrus, and lateral orbital gyrus. In addition, we identified the TPP connection areas in the thalamus, including the anterior and medial nuclei, and the lateral dorsal/lateral posterior nuclei. TPP fibers connected the thalamus with the ipsilateral prefrontal BAs 11, 47, 10, 46, 45, 9, and 8 seriatim from medial to lateral, layer by layer. Our results provide further details of the thalamic-prefrontal peduncle structure, and may aid future studies and a better understanding of the functional roles of the TPP in the human brain.

Onuf's nucleus X

DEFF Research Database (Denmark)

Schrøder, H D

1981-01-01

in the length of the nucleus was observed. Based on the cytoarchitecture the nucleus could be divided in three parts, a cranial, a dorsomedial and a ventrolateral. All parts of the nucleus consisted of chromatin-rich medium-sized neurons, and apparent direct appositions between different cells bodies as well...

Social cognitive and neurocognitive deficits in inpatients with unilateral thalamic lesions — pilot study

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Wilkos E

2015-04-01

Full Text Available Ewelina Wilkos,2 Timothy JB Brown,3 Ksenia Slawinska,1 Katarzyna A Kucharska2,3 1Department of Neurology, 2Department of Neuroses, Personality and Eating Disorders Institute of Psychiatry and Neurology, Warsaw, Poland; 3Department of Medical Education, Hull York Medical School, Hull, UK Background: The essential role of the thalamus in neurocognitive processes has been well documented. In contrast, relatively little is known about its involvement in social cognitive processes such as recognition of emotion, mentalizing, or empathy. The aim of the study: This study was designed to compare the performance of eight patients (five males, three females, mean age ± SD: 63.7±7.9 years at early stage of unilateral thalamic lesions and eleven healthy controls (six males, five females, 49.6±12.2 years in neurocognitive tests (CogState Battery: Groton Maze Learning Test, GML; Groton Maze Learning Test-Delayed Recall, GML-DR; Detection Task, DT; Identification Task, IT; One Card Learning Task, OCLT; One Back Task, OBT; Two Back Task, TBT; Set-Shifting Task, S-ST and other well-known tests (Benton Visual Retention Test, BVRT; California Verbal Learning Test, CVLT; The Rey-Osterrieth Complex Figure Test, ROCF; Trail Making Test, TMT part A and B; Color – Word Stroop Task, CWST; Verbal Fluency Test, VFT, and social cognitive tasks (The Penn Emotion Recognition Test, ER40; Penn Emotion Discrimination Task, EmoDiff40; The Penn Emotional Acuity Test, PEAT40; Reading the Mind in the Eyes Test, revised version II; Toronto Alexithymia Scale, TAS-20. Methods: Thalamic-damaged subjects were included if they experienced a single-episode ischemic stroke localized in right or left thalamus. The patients were examined at 3 weeks after the stroke onset. All were right handed. In addition, the following clinical scales were used: the Mini-Mental State Examination (MMSE, Spielberger State-Trait Anxiety Inventory (STAI, Beck Depression Inventory (BDI II. An inclusion

Classifiers for centrality determination in proton-nucleus and nucleus-nucleus collisions

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Altsybeev Igor

2017-01-01

Full Text Available Centrality, as a geometrical property of the collision, is crucial for the physical interpretation of nucleus-nucleus and proton-nucleus experimental data. However, it cannot be directly accessed in event-by-event data analysis. Common methods for centrality estimation in A-A and p-A collisions usually rely on a single detector (either on the signal in zero-degree calorimeters or on the multiplicity in some semi-central rapidity range. In the present work, we made an attempt to develop an approach for centrality determination that is based on machine-learning techniques and utilizes information from several detector subsystems simultaneously. Different event classifiers are suggested and evaluated for their selectivity power in terms of the number of nucleons-participants and the impact parameter of the collision. Finer centrality resolution may allow to reduce impact from so-called volume fluctuations on physical observables being studied in heavy-ion experiments like ALICE at the LHC and fixed target experiment NA61/SHINE on SPS.

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

Partial inelasticity coefficients of negative pions produced in hadron-nucleus and nucleus-nucleus collisions at high energies

International Nuclear Information System (INIS)

OLIMOV, K.; LUTPULLAEV, S.L.; PETROV, V.I.; OLIMOV, A.K.

2015-01-01

New experimental data on the partial inelasticity coefficients of negative pions produced in "1"6Op-collisions at 3.25 A GeV/s, pC-interactions at 4.2 and 9.9 GeV/s, and d,α,C(C)-collisions at 4.2 A GeV/s are presented. It is established that the behavior of partial inelasticity coefficients of pions at intermediate energies (<10 GeV) in hadron-nucleus collisions has a transitional character, reaching the limiting value at ultrahigh energies. It is shown that the mean values of partial inelasticity coefficients of pions produced in nucleus-nucleus collisions decrease with an increase in mass number of the projectile nucleus. (authors)

Acute reversible inactivation of the bed nucleus of stria terminalis induces antidepressant-like effect in the rat forced swimming test

Science.gov (United States)

2010-01-01

Background The bed nucleus of stria terminalis (BNST) is a limbic forebrain structure involved in hypothalamo-pituitary-adrenal axis regulation and stress adaptation. Inappropriate adaptation to stress is thought to compromise the organism's coping mechanisms, which have been implicated in the neurobiology of depression. However, the studies aimed at investigating BNST involvement in depression pathophysiology have yielded contradictory results. Therefore, the objective of the present study was to investigate the effects of temporary acute inactivation of synaptic transmission in the BNST by local microinjection of cobalt chloride (CoCl2) in rats subjected to the forced swimming test (FST). Methods Rats implanted with cannulae aimed at the BNST were submitted to 15 min of forced swimming (pretest). Twenty-four hours later immobility time was registered in a new 5 min forced swimming session (test). Independent groups of rats received bilateral microinjections of CoCl2 (1 mM/100 nL) before or immediately after pretest or before the test session. Additional groups received the same treatment and were submitted to the open field test to control for unspecific effects on locomotor behavior. Results CoCl2 injection into the BNST before either the pretest or test sessions reduced immobility in the FST, suggesting an antidepressant-like effect. No significant effect of CoCl2 was observed when it was injected into the BNST immediately after pretest. In addition, no effect of BNST inactivation was observed in the open field test. Conclusion These results suggest that acute reversible inactivation of synaptic transmission in the BNST facilitates adaptation to stress and induces antidepressant-like effects. PMID:20515458

Acute reversible inactivation of the bed nucleus of stria terminalis induces antidepressant-like effect in the rat forced swimming test

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Joca Sâmia RL

2010-06-01

Full Text Available Abstract Background The bed nucleus of stria terminalis (BNST is a limbic forebrain structure involved in hypothalamo-pituitary-adrenal axis regulation and stress adaptation. Inappropriate adaptation to stress is thought to compromise the organism's coping mechanisms, which have been implicated in the neurobiology of depression. However, the studies aimed at investigating BNST involvement in depression pathophysiology have yielded contradictory results. Therefore, the objective of the present study was to investigate the effects of temporary acute inactivation of synaptic transmission in the BNST by local microinjection of cobalt chloride (CoCl2 in rats subjected to the forced swimming test (FST. Methods Rats implanted with cannulae aimed at the BNST were submitted to 15 min of forced swimming (pretest. Twenty-four hours later immobility time was registered in a new 5 min forced swimming session (test. Independent groups of rats received bilateral microinjections of CoCl2 (1 mM/100 nL before or immediately after pretest or before the test session. Additional groups received the same treatment and were submitted to the open field test to control for unspecific effects on locomotor behavior. Results CoCl2 injection into the BNST before either the pretest or test sessions reduced immobility in the FST, suggesting an antidepressant-like effect. No significant effect of CoCl2 was observed when it was injected into the BNST immediately after pretest. In addition, no effect of BNST inactivation was observed in the open field test. Conclusion These results suggest that acute reversible inactivation of synaptic transmission in the BNST facilitates adaptation to stress and induces antidepressant-like effects.

Diabatic interaction potential for nucleus-nucleus collisions

International Nuclear Information System (INIS)

Noerenberg, W.; Lukasiak, A.

1984-01-01

Within a refined method for the construction of diabatic states allowing for the treatment of the full spin-orbit coupling, characteristic features of the diabatic potential for nucleus-nucleus collisions are investigated. Approximately 90% of the strong repulsion results from diabatic particle-hole excitations, while only 10% is due to compression. The diabatic interaction potential describes a physical situation intermediate between adiabatic and sudden approximations. (orig.)

Noradrenergic neurotransmission within the bed nucleus of the stria terminalis modulates the retention of immobility in the rat forced swimming test.

Science.gov (United States)

Nagai, Michelly M; Gomes, Felipe V; Crestani, Carlos C; Resstel, Leonardo B M; Joca, Sâmia R L

2013-06-01

The bed nucleus of the stria terminalis (BNST) is a limbic structure that has a direct influence on the autonomic, neuroendocrine, and behavioral responses to stress. It was recently reported that reversible inactivation of synaptic transmission within this structure causes antidepressant-like effects, indicating that activation of the BNST during stressful situations would facilitate the development of behavioral changes related to the neurobiology of depression. Moreover, noradrenergic neurotransmission is abundant in the BNST and has an important role in the regulation of emotional processes related to the stress response. Thus, this study aimed to test the hypothesis that activation of adrenoceptors within the BNST facilitates the development of behavioral consequences of stress. To investigate this hypothesis, male Wistar rats were stressed (forced swimming, 15 min) and 24 h later received intra-BNST injections of vehicle, WB4101, RX821002, CGP20712, or ICI118,551, which are selective α(1), α(2), β(1), and β(2) adrenoceptor antagonists, respectively, 10 min before a 5-min forced swimming test. It was observed that administration of WB4101 (10 and 15 nmol), CGP20712 (5 and 10 nmol), or ICI118,551 (5 nmol) into the BNST reduced the immobility time of rats subjected to forced swimming test, indicating an antidepressant-like effect. These findings suggest that activation of α(1), β(1), and β(2) adrenoceptors in the BNST could be involved in the development of the behavioral consequences of stress. © 2013 Wolters Kluwer Health | Lippincott Williams & Wilkins.

Increased thalamic perfusion as a characteristic finding with brain SPECT in patients with obsessive-compulsive disorder

International Nuclear Information System (INIS)

Mut, F.; Beretta, M.; Nunez, M.; Zamora, R.

2002-01-01

Aim: Obsessive-compulsive disorder (OCD) is a relatively frequent psychiatric condition affecting most commonly young patients. Correct diagnosis and follow-up is essential in order to apply effective therapy. However, some common characteristics have been reported with brain SPECT for OCD and depression, with several brain structures belonging to the limbic system involved in both conditions: frontal cortex, cingulate gyrus, caudate nucleus, thalamus and hippocampus, among others. The aim of this study was to investigate quantitative findings of brain SPECT in OCD compared to other psychiatric conditions such as depression and dementia. Material and Methods: We studied 33 patients, 22 women, ages 39.3±10.9 years. Fifteen patients had clinical diagnosis of OCD (8 women, 21∫8 ys.), 13 of bipolar or unipolar depression (11 women, 28±15 ys.) and 5 of senile dementia (3 women, 69±10 ys). All were injected in the basal state with a standard dose of 925 MBq (25 mCi) of 99mTc-ECD. Brain SPECT was performed with a dual-head camera equipped with a high-resolution collimator using 360 0 rotation, 120 angular steps and 15 sec/step in a 64x64 matrix with 1.5 x magnification. Reconstruction of transaxial tomograms was performed using filtered backprojection with a Metz filter. Attenuation correction was applied according to Chang's method. In order to calculate uptake ratios, regions of interest (ROIs) were placed on the right and left frontal cortex (RFron, LFron), anterior or posterior cingulate gyrus (Cing) according to the site of highest uptake recorded, both caudate nucleus (RCau, LCau), thalamus (Thal) and cerebellum (cer). Results: The findings are presented. Conclusion: Cingulate gyrus hyperactivity has been reported in patients with OCD and confirmed in our series, however not significantly different from that observed in depressed patients. The only distinct finding was higher thalamic activity in OCD patients compared to the other groups, suggesting that this

Isolated thalamic tuberculoma presenting as ataxic hemiparesis

Science.gov (United States)

Sahu, Ritesh; Patil, Tushar B; Kori, Prakash; Shukla, Rakesh

2013-01-01

Lacunar syndrome is a neurodeficit secondary to a deep cerebral lesion, usually because of microatheroma of small arteries. Ataxic hemiparesis (AH) is a lacunar syndrome with unilateral pyramidal weakness and ipsilateral ataxia. Thalamic tuberculoma, as a cause of AH, has not been previously described in the literature. We describe an elderly man who presented with left hemiparesis and ipsilateral ataxia. Clinical examination revealed upper motor neuron left facial paresis and left-sided hemiparesis. The patient had incoordination in left upper and lower limbs. Mantoux test was positive and erythrocyte sedimentation rate was elevated. MRI of brain showed a conglomerated hypointense lesion in the right thalamus with a peripheral hyperintensity on T1-weighted imaging and a hyperintense lesion in T2-weighted imaging with significant perilesional oedema, suggesting a tuberculoma. The patient was treated with antitubercular therapy and was symptomatically better at the 9 months follow-up. PMID:23580686

Fatal thalamic abscess secondary to dental infection.

Science.gov (United States)

Basyuni, Shadi; Sharma, Valmiki; Santhanam, Vijay; Ferro, Ashley

2015-12-17

We present the case of poor neurological recovery and subsequent death secondary to a thalamic abscess in a 53-year-old man. This patient initially presented with sudden dysarthria and left hemiparesis while driving. Neuroimaging showed a multilobular abscess involving the right thalamus with oedema extending to the basal ganglionic region and brainstem. The source of the abscess was initially unknown and it required draining multiple times while the different causes were being explored. The patient's neurological state along with intubation made for a difficult and inconclusive oral examination. It was only after neuroimaging included tooth-bearing areas that it became evident that this patient had extensive periodontal disease with multiple areas of periapical radiolucencies. The patient underwent complete dental clearance alongside repeated drainage of the abscess. Despite initial postoperative improvement, the patient never recovered from the neurological damage and died 3 weeks later. 2015 BMJ Publishing Group Ltd.

Classical gluon production amplitude for nucleus-nucleus collisions:First saturation correction in the projectile

International Nuclear Information System (INIS)

Chirilli, Giovanni A.; Kovchegov, Yuri V.; Wertepny, Douglas E.

2015-01-01

We calculate the classical single-gluon production amplitude in nucleus-nucleus collisions including the first saturation correction in one of the nuclei (the projectile) while keeping multiple-rescattering (saturation) corrections to all orders in the other nucleus (the target). In our approximation only two nucleons interact in the projectile nucleus: the single-gluon production amplitude we calculate is order-g"3 and is leading-order in the atomic number of the projectile, while resumming all order-one saturation corrections in the target nucleus. Our result is the first step towards obtaining an analytic expression for the first projectile saturation correction to the gluon production cross section in nucleus-nucleus collisions.

Deep Brain Stimulation of Medial Dorsal and Ventral Anterior Nucleus of the Thalamus in OCD: A Retrospective Case Series.

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Mohammad Maarouf

Full Text Available The current notion that cortico-striato-thalamo-cortical circuits are involved in the pathophysiology of obsessive-compulsive disorder (OCD has instigated the search for the most suitable target for deep brain stimulation (DBS. However, despite extensive research, uncertainty about the ideal target remains with many structures being underexplored. The aim of this report is to address a new target for DBS, the medial dorsal (MD and the ventral anterior (VA nucleus of the thalamus, which has thus far received little attention in the treatment of OCD.In this retrospective trial, four patients (three female, one male aged 31-48 years, suffering from therapy-refractory OCD underwent high-frequency DBS of the MD and VA. In two patients (de novo group the thalamus was chosen as a primary target for DBS, whereas in two patients (rescue DBS group lead implantation was performed in a rescue DBS attempt following unsuccessful primary stimulation.Continuous thalamic stimulation yielded no significant improvement in OCD symptom severity. Over the course of thalamic DBS symptoms improved in only one patient who showed "partial response" on the Yale-Brown Obsessive Compulsive (Y-BOCS Scale. Beck Depression Inventory scores dropped by around 46% in the de novo group; anxiety symptoms improved by up to 34%. In the de novo DBS group no effect of DBS on anxiety and mood was observable.MD/VA-DBS yielded no adequate alleviation of therapy-refractory OCD, the overall strategy in targeting MD/VA as described in this paper can thus not be recommended in DBS for OCD. The magnocellular portion of MD (MDMC, however, might prove a promising target in the treatment of mood related and anxiety disorders.

Deep Brain Stimulation of Medial Dorsal and Ventral Anterior Nucleus of the Thalamus in OCD: A Retrospective Case Series.

Science.gov (United States)

Maarouf, Mohammad; Neudorfer, Clemens; El Majdoub, Faycal; Lenartz, Doris; Kuhn, Jens; Sturm, Volker

2016-01-01

The current notion that cortico-striato-thalamo-cortical circuits are involved in the pathophysiology of obsessive-compulsive disorder (OCD) has instigated the search for the most suitable target for deep brain stimulation (DBS). However, despite extensive research, uncertainty about the ideal target remains with many structures being underexplored. The aim of this report is to address a new target for DBS, the medial dorsal (MD) and the ventral anterior (VA) nucleus of the thalamus, which has thus far received little attention in the treatment of OCD. In this retrospective trial, four patients (three female, one male) aged 31-48 years, suffering from therapy-refractory OCD underwent high-frequency DBS of the MD and VA. In two patients (de novo group) the thalamus was chosen as a primary target for DBS, whereas in two patients (rescue DBS group) lead implantation was performed in a rescue DBS attempt following unsuccessful primary stimulation. Continuous thalamic stimulation yielded no significant improvement in OCD symptom severity. Over the course of thalamic DBS symptoms improved in only one patient who showed "partial response" on the Yale-Brown Obsessive Compulsive (Y-BOCS) Scale. Beck Depression Inventory scores dropped by around 46% in the de novo group; anxiety symptoms improved by up to 34%. In the de novo DBS group no effect of DBS on anxiety and mood was observable. MD/VA-DBS yielded no adequate alleviation of therapy-refractory OCD, the overall strategy in targeting MD/VA as described in this paper can thus not be recommended in DBS for OCD. The magnocellular portion of MD (MDMC), however, might prove a promising target in the treatment of mood related and anxiety disorders.

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.

Thalamic glucose metabolism in temporal lobe epilepsy measured with 18F-FDG positron emission tomography (PET)

NARCIS (Netherlands)

Khan, N; Leenders, KL; Hajek, M; Maguire, P; Missimer, J; Wieser, HG

1997-01-01

Thalamic glucose metabolism has been studied in 24 patients suffering from temporal lobe epilepsy (TLE) using interictal F-18-fluorodeoxyglucose (FDG) positron emission tomography (PET). A total of 17 patients had a unilateral TL seizure onset, 11 of these patients had a mesial temporal lobe

Deafferentation in thalamic and pontine areas in severe traumatic brain injury.

Science.gov (United States)

Laouchedi, M; Galanaud, D; Delmaire, C; Fernandez-Vidal, S; Messé, A; Mesmoudi, S; Oulebsir Boumghar, F; Pélégrini-Issac, M; Puybasset, L; Benali, H; Perlbarg, V

2015-07-01

Severe traumatic brain injury (TBI) is characterized mainly by diffuse axonal injuries (DAI). The cortico-subcortical disconnections induced by such fiber disruption play a central role in consciousness recovery. We hypothesized that these cortico-subcortical deafferentations inferred from diffusion MRI data could differentiate between TBI patients with favorable or unfavorable (death, vegetative state, or minimally conscious state) outcome one year after injury. Cortico-subcortical fiber density maps were derived by using probabilistic tractography from diffusion tensor imaging data acquired in 24 severe TBI patients and 9 healthy controls. These maps were compared between patients and controls as well as between patients with favorable (FO) and unfavorable (UFO) 1-year outcome to identify the thalamo-cortical and ponto-thalamo-cortical pathways involved in the maintenance of consciousness. Thalamo-cortical and ponto-thalamo-cortical fiber density was significantly lower in TBI patients than in healthy controls. Comparing FO and UFO TBI patients showed thalamo-cortical deafferentation associated with unfavorable outcome for projections from ventral posterior and intermediate thalamic nuclei to the associative frontal, sensorimotor and associative temporal cortices. Specific ponto-thalamic deafferentation in projections from the upper dorsal pons (including the reticular formation) was also associated with unfavorable outcome. Fiber density of cortico-subcortical pathways as measured from diffusion MRI tractography is a relevant candidate biomarker for early prediction of one-year favorable outcome in severe TBI. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

A case of herpes simplex encephalitis(HSE) with a thalamic lesion

International Nuclear Information System (INIS)

Fujimori, Katsuya; Koike, Ryoko; Yuasa, Tatsuhiko; Miyatake, Tadashi; Ito, Jusuke.

1987-01-01

A case of herpes simplex encephalitis (HSE) with thalamic involvement was reported. The patient, a 27-year-old man, was admitted because of abnormal behavior and fever. He exhibited a disturbance of consciousness, meningial signs, and hyperreflexia. A CT scan of the head revealed diffuse brain edema. Acute encephalitis, especially HSE, was suspected, and so the intravenous administration of acyclovir and steroid therapy were started. The titer of herpes simplex Type 1 virus, as measured by CF and ELISA, was found to have increased amounts of serum and cerebrospinal fluid. 5 days after the onset, his consciousness worsened. He could not tell his name and scarely opened his eyes upon pain stimulation. A CT scan at this time showed low-density lesions in the left thalamus, cingulate gyrus, and the posterior portion of the putamen. About 5 days later, his consciousness level was increased, but he was mute. This symptom was thought to be thalamic aphasia, which might be correlative with the low-density lesions shown in the left thalamus by the CT scan. About 30 days after the onset of the disease, his speech became normal, and a CT scan at 51 hospital days showed no abnormality. The etiology of low-density lesions of the left thalamus in the CT scan is speculated to be as follows: firstly, vascular damage of circulation disturbance, and secondly a special affinity of herpes simplex Type 1 virus to the thalamus. (author)

Thalamic Massa Intermedia Duplication in a Dysmorphic 14 month-old Toddler.

Science.gov (United States)

Whitehead, Matthew T

2015-06-01

The massa intermedia is an inconstant parenchymal band connecting the medial thalami. It may be thickened in various disease processes such as Chiari II malformation or absent in other disease states. However, the massa intermedia may also be absent in up to 30% of normal human brains. To the best of my knowledge, detailed imaging findings of massa intermedia duplication have only been described in a single case report. An additional case of thalamic massa intermedia duplication discovered on a routine brain MR performed for dysmorphic facial features is reported herein.

Tc-99m ECD brain SPECT in patients with traumatic brain injury: evaluating distribution of hypoperfusion and assessment of cognitive and behavioral impairment in relation to thalamic hypoperfusion

Energy Technology Data Exchange (ETDEWEB)

Park, Soon Ah; Lim, Seok Tae; Sohn, Myung Hee [College of Medicine, Chonbuk National Univ., Chonju (Korea, Republic of)

2000-12-01

We evaluated the distribution of hypoperfusion in patients with traumatic brain injury (TBI) and the relationship of thalamic hypoperfusion to severity of cognitive and behavioral sequelae. Tc-99m ECD SPECT and MRI were performed in 103 patients (M/F=81/22, mean age 34.7{+-} 15.4 yrs) from 0.5 to 55 months (mean 10.3 months) after TBI. The patients were divided into three groups showing no abnormalities (G1), focal (G2) and diffuse injury (G3) on MRI. Psychometric tests assessed 11 cognitive or behavioral items. In all patients, we evaluated the distribution of hypoperfused areas in SPECT, and in 57/103 patients, neuropsychological (NP) abnormalities in patients with thalamic hypoperfusion were compared with those of patients without thalamic hypoperfusion. The perfusion dificits were most frequently located in the frontal lobe (G1, 42.3%: G2 34.5%: G3 33.3%), temporal lobe (24{approx}26%) thalami (21{approx}22.4%), parietal and occipital lobe ({<=}10%). Numbers of NP abnormalities in the cases of cortical hypoperfusion with or without concomitant thalamic hypoperfusion were following: the former 4.7{+-}1.5 and the latter 3.2{+-}1.4 in G1, 5.0{+-}1.1 and 4.8{+-}1.2 in G2, 6.8{+-}1.8 and 6.3{+-}1.1 in G3, respectively. This difference according to thalamic hypoperfusion was significant in G1 (p=0.002), but was not significant in G2 or G3. SPECT in patients with TBI had demonstrated hypoperfusion mostly involving the frontal, temporal and thalami. In normal group on MRI, frontal hypoperfusion was more prominent than that of any other group, Furthermore in this group, SPECT could predict severity of NP outcome by concomitant thalamic hypoperfusion with cerebral cortical abnormalities.

Tc-99m ECD brain SPECT in patients with traumatic brain injury: evaluating distribution of hypoperfusion and assessment of cognitive and behavioral impairment in relation to thalamic hypoperfusion

International Nuclear Information System (INIS)

Park, Soon Ah; Lim, Seok Tae; Sohn, Myung Hee

2000-01-01

We evaluated the distribution of hypoperfusion in patients with traumatic brain injury (TBI) and the relationship of thalamic hypoperfusion to severity of cognitive and behavioral sequelae. Tc-99m ECD SPECT and MRI were performed in 103 patients (M/F=81/22, mean age 34.7± 15.4 yrs) from 0.5 to 55 months (mean 10.3 months) after TBI. The patients were divided into three groups showing no abnormalities (G1), focal (G2) and diffuse injury (G3) on MRI. Psychometric tests assessed 11 cognitive or behavioral items. In all patients, we evaluated the distribution of hypoperfused areas in SPECT, and in 57/103 patients, neuropsychological (NP) abnormalities in patients with thalamic hypoperfusion were compared with those of patients without thalamic hypoperfusion. The perfusion dificits were most frequently located in the frontal lobe (G1, 42.3%: G2 34.5%: G3 33.3%), temporal lobe (24∼26%) thalami (21∼22.4%), parietal and occipital lobe (≤10%). Numbers of NP abnormalities in the cases of cortical hypoperfusion with or without concomitant thalamic hypoperfusion were following: the former 4.7±1.5 and the latter 3.2±1.4 in G1, 5.0±1.1 and 4.8±1.2 in G2, 6.8±1.8 and 6.3±1.1 in G3, respectively. This difference according to thalamic hypoperfusion was significant in G1 (p=0.002), but was not significant in G2 or G3. SPECT in patients with TBI had demonstrated hypoperfusion mostly involving the frontal, temporal and thalami. In normal group on MRI, frontal hypoperfusion was more prominent than that of any other group, Furthermore in this group, SPECT could predict severity of NP outcome by concomitant thalamic hypoperfusion with cerebral cortical abnormalities

K+-nucleus interaction

International Nuclear Information System (INIS)

Gibbs, W.R.

1984-01-01

The K + -nucleus system is reviewed and comparison with data is made. The principal conclusions are that the theoretical uncertainties in relating the K + -nucleus interaction to the K + -nucleon interaction are very small and hence the positive kaon makes an excellent probe of the nucleus. It is suggested that this particle may be more sensitive to non-nucleonic degrees of freedom (especially quarks) than classical probes

TWO-PHOTON PHYSICS IN NUCLEUS-NUCLEUS COLLISIONS AT RHIC

International Nuclear Information System (INIS)

Nystrand, J.; Klein, S.

1998-01-01

Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent two-photon and photonuclear processes at RHIC. The rates for these interactions will be high. The coherent coupling of all the protons in the nucleus enhances the equivalent photon flux by a factor Z 2 up to an energy of ∼ 3 GeV. The plans for studying coherent interactions with the STAR experiment will be discussed. Experimental techniques for separating signal from background will be presented

Two-photon physics in nucleus-nucleus collisions at RHIC

International Nuclear Information System (INIS)

Nystrand, J.; Klein, S.

1998-01-01

Ultra-relativistic heavy-ions carry strong electromagnetic and nuclear fields. Interactions between these fields in peripheral nucleus-nucleus collisions can probe many interesting physics topics. This presentation will focus on coherent two-photon and photonuclear processes at RHIC. The rates for these interactions will be high. The coherent coupling of all the protons in the nucleus enhances the equivalent photon flux by a factor Z 2 up to an energy of ∼ 3 GeV. The plans for studying coherent interactions with the STAR experiment will be discussed. Experimental techniques for separating signal from background will be presented

Nonlinear predictive control for adaptive adjustments of deep brain stimulation parameters in basal ganglia-thalamic network.

Science.gov (United States)

Su, Fei; Wang, Jiang; Niu, Shuangxia; Li, Huiyan; Deng, Bin; Liu, Chen; Wei, Xile

2018-02-01

The efficacy of deep brain stimulation (DBS) for Parkinson's disease (PD) depends in part on the post-operative programming of stimulation parameters. Closed-loop stimulation is one method to realize the frequent adjustment of stimulation parameters. This paper introduced the nonlinear predictive control method into the online adjustment of DBS amplitude and frequency. This approach was tested in a computational model of basal ganglia-thalamic network. The autoregressive Volterra model was used to identify the process model based on physiological data. Simulation results illustrated the efficiency of closed-loop stimulation methods (amplitude adjustment and frequency adjustment) in improving the relay reliability of thalamic neurons compared with the PD state. Besides, compared with the 130Hz constant DBS the closed-loop stimulation methods can significantly reduce the energy consumption. Through the analysis of inter-spike-intervals (ISIs) distribution of basal ganglia neurons, the evoked network activity by the closed-loop frequency adjustment stimulation was closer to the normal state. Copyright © 2017 Elsevier Ltd. All rights reserved.

Functionalized active-nucleus complex sensor

Science.gov (United States)

Pines, Alexander; Wemmer, David E.; Spence, Megan; Rubin, Seth

2003-11-25

A functionalized active-nucleus complex sensor that selectively associates with one or more target species, and a method for assaying and screening for one or a plurality of target species utilizing one or a plurality of functionalized active-nucleus complexes with at least two of the functionalized active-nucleus complexes having an attraction affinity to different corresponding target species. The functionalized active-nucleus complex has an active-nucleus and a targeting carrier. The method involves functionalizing an active-nucleus, for each functionalized active-nucleus complex, by incorporating the active-nucleus into a macromolucular or molecular complex that is capable of binding one of the target species and then bringing the macromolecular or molecular complexes into contact with the target species and detecting the occurrence of or change in a nuclear magnetic resonance signal from each of the active-nuclei in each of the functionalized active-nucleus complexes.

Strangeness production in hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions in the dual parton model

International Nuclear Information System (INIS)

Moehring, H.; Ranft, J.; Capella, A.; Tran Thanh Van, J.

1993-01-01

Λ, bar Λ, and K S 0 production is studied in a Monte Carlo dual parton model for hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions with an SU(3) symmetric sea for chain formation (chain ends) but strangeness suppression in the chain fragmentation process. Additionally, (qq)-(bar q bar q) production from the sea was introduced into the chain formation process with the same probability as for the q→qq branching within the chain decay process. With these assumptions, multiplicity ratios and Feynman-x distributions for strange particles in h-h and multiplicity ratios in heavy ion collisions are reasonably well reproduced

The nuclear response and the imaginary potential for nucleus-nucleus collisions

International Nuclear Information System (INIS)

Phatak, S.C.; Sinha, B.

1983-01-01

The Fermi-gas model is used in this paper to study the nucleus-nucleus collision. The field produced by one of the nuclei is considered to act on nucleons in the other nucleus, which is treated as a Fermi gas of radius R. The imaginary part of the (non-local) nucleus-nucleus potential is then computed by evaluating the energy-conserving second-order term in which the intermediate states are particle-hole excitations produced in the Fermi gas. The equivalent local potential, obtained by using the Perey-Saxon method, is compared with phenomenological imaginary potentials. Later it is shown that, in the limit of small range of non-locality, the imaginary potential can be related to the nuclear response function. With this, one can write the nuclear friction coefficient that is used in phenomenological analyses of heavy-ion collisions in terms of the imaginary potential. (orig.)

Using multiple bed load measurements: Toward the identification of bed dilation and contraction in gravel-bed rivers

Science.gov (United States)

Marquis, G. A.; Roy, A. G.

2012-02-01

This study examines bed load transport processes in a small gravel-bed river (Béard Creek, Québec) using three complementary methods: bed elevation changes between successive floods, bed activity surveys using tags inserted into the bed, and bed load transport rates from bed load traps. The analysis of 20 flood events capable of mobilizing bed material led to the identification of divergent results among the methods. In particular, bed elevation changes were not consistent with the bed activity surveys. In many cases, bed elevation changes were significant (1 to 2 times the D50) even if the bed surface had not been activated during the flood, leading to the identification of processes of bed dilation and contraction that occurred over 10% to 40% of the bed surface. These dynamics of the river bed prevent accurate derivation of bed load transport rates from topographic changes, especially for low magnitude floods. This paper discusses the mechanisms that could explain the dilation and contraction of particles within the bed and their implications in fluvial dynamics. Bed contraction seems to be the result of the winnowing of the fine sediments under very low gravel transport. Bed dilation seems to occur on patches of the bed at the threshold of motion where various processes such as fine sediment infiltration lead to the maintenance of a larger sediment framework volume. Both processes are also influenced by flood history and the initial local bed state and in turn may have a significant impact on sediment transport and morphological changes in gravel-bed rivers.

Superselective Thalamotomy in the Most Lateral Part of the Ventralis Intermedius Nucleus for Controlling Essential and Parkinsonian Tremor.

Science.gov (United States)

Hirato, Masafumi; Miyagishima, Takaaki; Takahashi, Akio; Yoshimoto, Yuhei

2018-01-01

The minimum and essential thalamic areas for reducing tremor were investigated in cases treated by superselective thalamotomy in the most lateral part of the ventralis intermedius nucleus (mlp-VIM). Stereotactic superselective VIM thalamotomy with depth microrecording was performed in 21 patients with essential tremor (ET) and 15 patients with tremor-dominant Parkinson disease (PD). A very small and narrow (axial plane) therapeutic lesion was formed as a square on the sagittal plane and inverse V on the axial plane in the mlp-VIM, which covered the kinesthetic response area topographically related to tremor. Patients with ET were followed up for 4.7 ± 3.0 years and patients with PD for 7.9 ± 3.9 years. Almost complete tremor control was achieved in all patients immediately after surgery and continued for up to 8 years. A few adverse events were recognized but disappeared within 1 month without 1 patient with thalamic hemorrhage. The medial border of the therapeutic lesion was significantly more lateral in both patients with ET and patients with PD than the calculated standard target point and was in patients with PD than in patients with ET. The mean width was only about 2.4 mm. The individual differences of the adequate location of the therapeutic lesion were significantly greater in the ET than in the PD group. The important area for reducing tremor was small and narrow and was located in the mlp-VIM, where the proprioceptive ascending signals from the tremor-dominant body part are conducted. Superselective thalamotomy in the mlp-VIM was safe and effective for the long-term in patients with ET and PD. Copyright © 2017 Elsevier Inc. All rights reserved.

Low thalamic NAA-concentration corresponds to strong neural activation in working memory in Kleine-Levin syndrome.

Science.gov (United States)

Vigren, Patrick; Tisell, Anders; Engström, Maria; Karlsson, Thomas; Leinhard Dahlqvist, Olof; Lundberg, Peter; Landtblom, Anne-Marie

2013-01-01

Kleine Levin Syndrome (KLS) is a rare disorder of periodic hypersomnia and behavioural disturbances in young individuals. It has previously been shown to be associated with disturbances of working memory (WM), which, in turn, was associated with higher activation of the thalamus with increasing WM load, demonstrated with functional magnetic resonance imaging (fMRI). In this study we aimed to further elucidate how these findings are related to the metabolism of the thalamus. fMRI and magnetic resonance spectroscopy were applied while performing a WM task. Standard metabolites were examined: n-acetylaspartate (NAA), myo-inositol, choline, creatine and glutamate-glutamine. Fourteen KLS-patients and 15 healthy controls participated in the study. The patients with active disease were examined in asymptomatic periods. There was a statistically significant negative correlation between thalamic fMRI-activation and thalamic NAA, i.e., high fMRI-activation corresponded to low NAA-levels. This correlation was not seen in healthy controls. Thalamic levels of NAA in patients and controls showed no significant differences between the groups. None of the other metabolites showed any co-variation with fMRI-activation. This study shows negative correlation between NAA-levels and fMRI-activity in the left thalamus of KLS-patients while performing a WM task. This correlation could not be found in healthy control subjects, primarily interpreted as an effect of increased effort in the patient group upon performing the task. It might indicate a disturbance in the neuronal networks responsible for WM in KLS patients, resulting in higher effort at lower WM load, compared with healthy subjects. The general relationship between NAA and BOLD-signal is also discussed in the article.

An autopsy-verified case of FTLD-TDP type A with upper motor neuron-predominant motor neuron disease mimicking MM2-thalamic-type sporadic Creutzfeldt-Jakob disease.

Science.gov (United States)

Hayashi, Yuichi; Iwasaki, Yasushi; Takekoshi, Akira; Yoshikura, Nobuaki; Asano, Takahiko; Mimuro, Maya; Kimura, Akio; Satoh, Katsuya; Kitamoto, Tetsuyuki; Yoshida, Mari; Inuzuka, Takashi

2016-11-01

Here we report an autopsy-verified case of frontotemporal lobar degeneration (FTLD)-transactivation responsive region (TAR) DNA binding protein (TDP) type A with upper motor neuron-predominant motor neuron disease mimicking MM2-thalamic-type sporadic Creutzfeldt-Jakob disease (sCJD). A 69-year-old woman presented with an 11-month history of progressive dementia, irritability, insomnia, and gait disturbance without a family history of dementia or prion disease. Neurological examination revealed severe dementia, frontal signs, and exaggerated bilateral tendon reflexes. Periodic sharp-wave complexes were not observed on the electroencephalogram. Brain diffusion MRI did not reveal abnormal changes. An easy Z score (eZIS) analysis for 99m Tc-ECD-single photon emission computed tomography ( 99m Tc-ECD-SPECT) revealed a bilateral decrease in thalamic regional cerebral blood flow (rCBF). PRNP gene analysis demonstrated methionine homozygosity at codon 129 without mutation. Cerebrospinal fluid (CSF) analysis showed normal levels of both 14-3-3 and total tau proteins. Conversely, prion protein was slowly amplified in the CSF by a real-time quaking-induced conversion assay. Her symptoms deteriorated to a state of akinetic mutism, and she died of sudden cardiac arrest, one year after symptom onset.  Despite the SPECT results supporting a clinical diagnosis of MM2-thalamic-type sCJD, a postmortem assessment revealed that this was a case of FTLD-TDP type A, and excluded prion disease. Thus, this case indicates that whereas a bilateral decreasing thalamic rCBF detected by 99m Tc-ECD-SPECT can be useful for diagnosing MM2-thalamic-type sCJD, it is not sufficiently specific. Postmortem diagnosis remains the gold standard for the diagnosis of this condition.

Effective nucleus-nucleus potentials derived from the generator coordinate method

Energy Technology Data Exchange (ETDEWEB)

Friedrich, H; Canto, L F [Oxford Univ. (UK). Dept. of Theoretical Physics

1977-11-07

The equivalence of the generator coordinate method (GCM) and the resonating group method (RGM) and the formal equivalence of the RGM and the orthogonality condition model (OCM) lead to a relation connecting the effective nucleus-nucleus potentials of the OCM with matrix elements of the GCM. This relation may be used to derive effective nucleus-nucleus potentials directly from GCM matrix elements without explicit reference to the potentials of the RGM. In a first application local and l-independent effective potentials are derived from diagonal GCM matrix elements which represent the energy surfaces of a two-centre shell model. Using these potentials the OCM can reproduce the results of a full RGM calculation very well for the elastic scattering of two ..cap alpha..-particles and fairly well for elastic /sup 16/O-/sup 16/O scattering.

Experimental search for compression phenomena in fast nucleus--nucleus collisions

International Nuclear Information System (INIS)

Schopper, E.; Baumgardt, H.G.; Obst, E.

1977-01-01

The occurrence of compression phenomena and shock waves, connected with the increase of the density of the nuclear matter during the interpenetration of two fast nuclei, are discussed. Current experiments dealing with this problem are reviewed. Before considering the mechanism of the interpenetration of two fast nuclei it may be useful to look at more simple situations, i.e., proton-proton interactions, then to envelop them with nuclear matter, considering proton-nucleus interactions. Only very general features are described, which may give suggestions for the understanding of the nucleus-nucleus impact

The Neuronal Transition Probability (NTP) Model for the Dynamic Progression of Non-REM Sleep EEG: The Role of the Suprachiasmatic Nucleus

CERN Document Server

Merica, H

2011-01-01

Little attention has gone into linking to its neuronal substrates the dynamic structure of non-rapid-eye-movement (NREM) sleep, defined as the pattern of time-course power in all frequency bands across an entire episode. Using the spectral power time-courses in the sleep electroencephalogram (EEG), we showed in the typical first episode, several moves towards-and-away from deep sleep, each having an identical pattern linking the major frequency bands beta, sigma and delta. The neuronal transition probability model (NTP) - in fitting the data well - successfully explained the pattern as resulting from stochastic transitions of the firing-rates of the thalamically-projecting brainstem-activating neurons, alternating between two steady dynamic-states (towards-and-away from deep sleep) each initiated by a so-far unidentified flip-flop. The aims here are to identify this flip-flop and to demonstrate that the model fits well all NREM episodes, not just the first. Using published data on suprachiasmatic nucleus (SCN...

The mechanism of nuclear energy release in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

1998-01-01

The mechanism of intranuclear energy release in reactions induced by nucleus-nucleus collisions at energies higher than ∼ 0.5 GeV/nucl. is presented - as prompted experimentally. The intranuclear energy release goes through local damages of the colliding nuclei

The correlation between the transverse polarization and transverse momentum of lambda produced in relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Ye Yunxiu; Zhou Xin; Ji Gang; Su Shufang; Zhu Guohuai

1996-01-01

The transverse polarization of lambda produced in relativistic nucleus-nucleus collisions is determined. The effect from the interaction between spin moment and magnetic field is corrected. The near zero transverse polarization and non-correlation between transverse polarization and transverse momentum are obtained and compared to ones obtained from the nucleus-nucleus interactions at lower energies. This comparison shows that the production mechanism of lambdas in the relativistic nucleus-nucleus collisions is different from one in the nucleus-nucleus reactions at lower energies

Formation of proton-fragments in hadron-nucleus and nucleus-nucleus collisions at high energies

International Nuclear Information System (INIS)

Bazarov, E.Kh.; Olimov, K.; Petrov, V.I.; Lutpullaev, S.L.

2006-01-01

Full text: The investigation of production of protons in hadron- and nucleus-nucleus interactions is a key problem allowing one to establish the singularities of dynamics of nuclear interactions. The formation of proton-fragments at high energies of colliding particles proceeds within both the interaction of hadrons with nuclei and in the process of decay of the nucleus or its de-excitation at peripheral interactions. At different stages of interaction of impinging particle with target nucleus, the different mechanisms of formation of proton-fragments: the direct knock-out of intranuclear nucleons in the process of high energy cascade of an initial hadron, intranuclear cascade of produced particles, decay of the excited multi-nucleon fragments and of the thermalized remnant nucleus, and the coalescence of nuclear fragments to the new clusters are realized with the certain probability, connected to the interaction parameters (the interaction energy, the parameter of collision, the intranuclear density, the configuration of Fermi momentum of nucleons and clusters of target nucleus et al.). In its turn, the mechanisms of formation of the final nuclear fragments are closely related to the type of excitation of an initial nucleus. The peripheral interactions proceed at small transfers of the momentum of an impinging particle and represent the wide class of reactions covering the processes from diffractive or coulomb collective excitations of the whole nucleus to the direct quasi-elastic knock-out of the separate nucleons. Non-peripheral interactions are caused by comparatively high local transfers of momentum to the intranuclear clusters allowing the development of intranuclear cascade and the asymmetric redistribution of energy of an impinging particle. The central collisions causing the full decay of nucleus on nucleons or few-nucleon fragments, are the limiting case of the maximal development of the intranuclear cascade. The interaction of the initial particles with

Nucleus-nucleus interactions in the transition energy regime

International Nuclear Information System (INIS)

Volant, C.

1985-02-01

There are at least two ways for studying large interactions in nucleus-nucleus collisions. One way is to use the method of angular correlations between fission fragments. The aim of the experiments presented here was to make a survey on the role of the various experimental parameters. In that respect three targets have been studied and different projectiles and bombarding energies have been used. Results are presented and discussed

The application of a phenomenological model to inelastic nucleus-nucleus interactions for laboratory momenta below 5 GeV/c per nucleon of the incident nucleus

International Nuclear Information System (INIS)

Grishin, V.G.; Kladnitskaya, E.N.

1985-01-01

A phenomenological model for inelastic nucleus-nucleus interactions at momenta below 5 GeV/c per nucleon is described. Particle interactions inside the interacting nuclei are described by phenomenological models of hadron-nucleus and hadron-nucleon interactions. The Monte-Carlo model provides the kinematic variables for a set of events under study. The comparison of the model inclusive distri-- butions for different particles and nucleus-nucleus interactions agrees well with the experimental data

Acute Korsakoff-like amnestic syndrome resulting from left thalamic infarction following a right hippocampal hemorrhage.

Science.gov (United States)

Rahme, R; Moussa, R; Awada, A; Ibrahim, I; Ali, Y; Maarrawi, J; Rizk, T; Nohra, G; Okais, N; Samaha, E

2007-04-01

Korsakoff-like amnestic syndromes have been rarely described following structural lesions of the central nervous system. In this report, we describe a case of acute Korsakoff-like syndrome resulting from the combination of a left anteromedian thalamic infarct and a right hippocampal hemorrhage. We also review the literature relevant to the neuropathology and pathophysiology of Korsakoff syndrome and anterograde amnesia.

Sensory disturbance, CT, and somatosensory evoked potentials in thalamic hemorrhages

International Nuclear Information System (INIS)

Koga, Hisanobu; Miyazaki, Takayoshi; Miyazaki, Hisaya

1985-01-01

Thalamic hemorrhages often lead to sensory disturbances. However, no effective method for the evaluation of their prognoses has yet been clinically utilized. The somatosensory evoked potential (SEP) has been reported as an effective method, but it remains controversial. A CT scan is eminently suitable for determining the size and position of the hemorrhage. However, the correlation between the localization of the hematoma on the CT scan and the sensory distrubance has not been investigated fully. The authors selected 20 cases with the chronic stage of a thalamic hemorrhage. Each one was clinically evaluated as to sensory disturbance; they were then classified into the following five groups: Group 1: no sensory deficit (3 cases); Group 2: complete recovery from initial deficit (2 cases); Group 3: mild hypesthesia (5 cases); Group 4: severe hypesthesia (5 cases), and Group 5: paresthesia or dysesthesia (5 cases). Also, the CT scan was investigated with regard to the localization of the hematoma and the SEP. We could thus find a characteristic pattern in each group. The results may be summarized as follows. 1. The correlation between the degree of the sensory disturbance and the size and expansion of the hematoma was clearly detected. Especially, the most severe sensory disturbance was found in the hematoma extending to the lateral nuclear and ventral nuclear regions. 2. In Group 1 and 2, each SEP component (N 1 N 2 N 3 ) was shown to be normal. In Group 3, SEP components could be detected, but not completely. In Group 4, no components at all could be found. 3. In Group 5, all cases were small hematoma localized in the lateral nuclear region of the thalamus, while the N 3 components were prolonged on the SEP findings. The authors demonstrate the results and discuss the correlation between the sensory disturbance and the CT or SEP findings. (author)

Nucleus Ruber of Actinopterygians.

Science.gov (United States)

Nakayama, Tomoya; Miyajima, Satoshi; Nishino, Hirotaka; Narita, Junya; Abe, Hideki; Yamamoto, Naoyuki

2016-01-01

Nucleus ruber is known as an important supraspinal center that controls forelimb movements in tetrapods, and the rubral homologue may serve similar functions in fishes (motor control of pectoral fin). However, two apparently different structures have been identified as 'nucleus ruber' in actinopterygians. One is nucleus ruber of Goldstein (1905) (NRg), and the other nucleus ruber of Nieuwenhuys and Pouwels (1983) (NRnp). It remains unclear whether one of these nuclei (or perhaps both) is homologous to tetrapod nucleus ruber. To resolve this issue from a phylogenetic point of view, we have investigated the distribution of tegmental neurons retrogradely labeled from the spinal cord in eight actinopterygian species. We also investigated the presence/absence of the two nuclei with Nissl- or Bodian-stained brain section series of an additional 28 actinopterygian species by comparing the morphological features of candidate rubral neurons with those of neurons revealed by the tracer studies. Based on these analyses, the NRg was identified in all actinopterygians investigated in the present study, while the NRnp appears to be absent in basal actinopterygians. The phylogenetic distribution pattern indicates that the NRg is the more likely homologue of nucleus ruber, and the NRnp may be a derived nucleus that emerged during the course of actinopterygian evolution. © 2016 S. Karger AG, Basel.

Description of inelastic nucleus-nucleus interactions at medium energy using dual parton model

International Nuclear Information System (INIS)

Polanski, A.; Shmakov, S.Yu.; Uzhinskij, V.V.

1989-01-01

It is shown that the dual parton model taking into account the processes of diffraction dissociation to the low mass states and finite energy corrections to the asymptotic Abramovski-Gribov-Kancheli cutting rules allows satisfactory description of existing experimental data on hadron-nucleus and nucleus-nucleus interactions at medium energy. (orig.)

Central thalamic deep brain stimulation for support of forebrain arousal regulation in the minimally conscious state.

Science.gov (United States)

Schiff, Nicholas D

2013-01-01

This chapter considers the use of central thalamic deep brain stimulation (CT/DBS) to support arousal regulation mechanisms in the minimally conscious state (MCS). CT/DBS for selected patients in a MCS is first placed in the historical context of prior efforts to use thalamic electrical brain stimulation to treat the unconscious clinical conditions of coma and vegetative state. These previous studies and a proof of concept result from a single-subject study of a patient in a MCS are reviewed against the background of new population data providing benchmarks of the natural history of vegetative and MCSs. The conceptual foundations for CT/DBS in selected patients in a MCS are then presented with consideration of both circuit and cellular mechanisms underlying recovery of consciousness identified from empirical studies. Directions for developing future generalizable criteria for CT/DBS that focus on the integrity of necessary brain systems and behavioral profiles in patients in a MCS that may optimally response to support of arousal regulation mechanisms are proposed. © 2013 Elsevier B.V. All rights reserved.

High frequency stimulation of the entopeduncular nucleus sets the cortico-basal ganglia network to a new functional state in the dystonic hamster.

Science.gov (United States)

Reese, René; Charron, Giselle; Nadjar, Agnès; Aubert, Incarnation; Thiolat, Marie-Laure; Hamann, Melanie; Richter, Angelika; Bezard, Erwan; Meissner, Wassilios G

2009-09-01

High frequency stimulation (HFS) of the internal pallidum is effective for the treatment of dystonia. Only few studies have investigated the effects of stimulation on the activity of the cortex-basal ganglia network. We here assess within this network the effect of entopeduncular nucleus (EP) HFS on the expression of c-Fos and cytochrome oxidase subunit I (COI) in the dt(sz)-hamster, a well-characterized model of paroxysmal dystonia. In dt(sz)-hamsters, we identified abnormal activity in motor cortex, basal ganglia and thalamus. These structures have already been linked to the pathophysiology of human dystonia. EP-HFS (i) increased striatal c-Fos expression in controls and dystonic hamsters and (ii) reduced thalamic c-Fos expression in dt(sz)-hamsters. EP-HFS had no effect on COI expression. The present results suggest that EP-HFS induces a new network activity state which may improve information processing and finally reduces the severity of dystonic attacks in dt(sz)-hamsters.

Dynamics of epileptic activity in a peculiar case of childhood absence epilepsy and correlation with thalamic levels of GABA

Directory of Open Access Journals (Sweden)

Alberto Leal

2016-01-01

Significance: In a clinical case of CAE with EEG and fMRI-BOLD manifestations restricted to one hemisphere, we found an associated increase in thalamic GABA concentration consistent with a role for this abnormality in human CAE.

Thalamic synaptic transmission of sensory information modulated by synergistic interaction of adenosine and serotonin.

Science.gov (United States)

Yang, Ya-Chin; Hu, Chun-Chang; Huang, Chen-Syuan; Chou, Pei-Yu

2014-03-01

The thalamic synapses relay peripheral sensory information to the cortex, and constitute an important part of the thalamocortical network that generates oscillatory activities responsible for different vigilance (sleep and wakefulness) states. However, the modulation of thalamic synaptic transmission by potential sleep regulators, especially by combination of regulators in physiological scenarios, is not fully characterized. We found that somnogen adenosine itself acts similar to wake-promoting serotonin, both decreasing synaptic strength as well as short-term depression, at the retinothalamic synapse. We then combined the two modulators considering the coexistence of them in the hypnagogic (sleep-onset) state. Adenosine plus serotonin results in robust synergistic inhibition of synaptic strength and dramatic transformation of short-term synaptic depression to facilitation. These synaptic effects are not achievable with a single modulator, and are consistent with a high signal-to-noise ratio but a low level of signal transmission through the thalamus appropriate for slow-wave sleep. This study for the first time demonstrates that the sleep-regulatory modulators may work differently when present in combination than present singly in terms of shaping information flow in the thalamocortical network. The major synaptic characters such as the strength and short-term plasticity can be profoundly altered by combination of modulators based on physiological considerations. © 2013 International Society for Neurochemistry.

Glutamate and Opioid Antagonists Modulate Dopamine Levels Evoked by Innately Attractive Male Chemosignals in the Nucleus Accumbens of Female Rats.

Science.gov (United States)

Sánchez-Catalán, María-José; Orrico, Alejandro; Hipólito, Lucía; Zornoza, Teodoro; Polache, Ana; Lanuza, Enrique; Martínez-García, Fernando; Granero, Luis; Agustín-Pavón, Carmen

2017-01-01

Sexual chemosignals detected by vomeronasal and olfactory systems mediate intersexual attraction in rodents, and act as a natural reinforcer to them. The mesolimbic pathway processes natural rewards, and the nucleus accumbens receives olfactory information via glutamatergic projections from the amygdala. Thus, the aim of this study was to investigate the involvement of the mesolimbic pathway in the attraction toward sexual chemosignals. Our data show that female rats with no previous experience with males or their chemosignals display an innate preference for male-soiled bedding. Focal administration of the opioid antagonist β-funaltrexamine into the posterior ventral tegmental area does not affect preference for male chemosignals. Nevertheless, exposure to male-soiled bedding elicits an increase in dopamine efflux in the nucleus accumbens shell and core, measured by microdialysis. Infusion of the opioid antagonist naltrexone in the accumbens core does not significantly affect dopamine efflux during exposure to male chemosignals, although it enhances dopamine levels 40 min after withdrawal of the stimuli. By contrast, infusion of the glutamate antagonist kynurenic acid in the accumbens shell inhibits the release of dopamine and reduces the time that females spend investigating male-soiled bedding. These data are in agreement with previous reports in male rats showing that exposure to opposite-sex odors elicits dopamine release in the accumbens, and with data in female mice showing that the behavioral preference for male chemosignals is not affected by opioidergic antagonists. We hypothesize that glutamatergic projections from the amygdala into the accumbens might be important to modulate the neurochemical and behavioral responses elicited by sexual chemosignals in rats.

Analysis of correlation between white matter changes and functional responses in thalamic stroke: a DTI & EEG study.

Science.gov (United States)

Duru, Adil Deniz; Duru, Dilek Göksel; Yumerhodzha, Sami; Bebek, Nerses

2016-06-01

Diffusion tensor imaging (DTI) allows in vivo structural brain mapping and detection of microstructural disruption of white matter (WM). One of the commonly used parameters for grading the anisotropic diffusivity in WM is fractional anisotropy (FA). FA value helps to quantify the directionality of the local tract bundle. Therefore, FA images are being used in voxelwise statistical analyses (VSA). The present study used Tract-Based Spatial Statistics (TBSS) of FA images across subjects, and computes the mean skeleton map to detect voxelwise knowledge of the tracts yielding to groupwise comparison. The skeleton image illustrates WM structure and shows any changes caused by brain damage. The microstructure of WM in thalamic stroke is investigated, and the VSA results of healthy control and thalamic stroke patients are reported. It has been shown that several skeleton regions were affected subject to the presence of thalamic stroke (FWE, p EEG (qEEG) scores and neurophysiological tests with the FA skeleton for the entire test group is also investigated. We compared measurements that are related to the same fibers across subjects, and discussed implications for VSA of WM in thalamic stroke cases, for the relationship between behavioral tests and FA skeletons, and for the correlation between the FA maps and qEEG scores.Results obtained through the regression analyses did not exceed the corrected statistical threshold values for multiple comparisons (uncorrected, p EEG, cingulum bundle and corpus callosum were found to be related. These areas are parts of the Default Mode Network (DMN) where DMN is known to be involved in resting state EEG theta activity. The relation between the EEG alpha band power values and FA values of the skeleton was found to support the cortico-thalamocortical cycles for both subject groups. Further, the neurophysiological tests including Benton Face Recognition (BFR), Digit Span test (DST), Warrington Topographic Memory test (WTMT

Dimuon enhancement in nucleus-nucleus ultrarelativistic interactions

International Nuclear Information System (INIS)

Bordalo, Paula; Abreu, M.C.; Alessandro, B.; Alexa, C.; Arnaldi, R.; Astruc, J.; Atayan, M.; Baglin, C.; Baldit, A.; Bedjidian, M.; Bellaiche, F.; Beole, S.; Bohrani, A.; Boldea, V.; Bussiere, A.; Capelli, L.; Caponi, V.; Casagrande, L.; Castor, J.; Chambon, T.; Chaurand, B.; Chevrot, I.; Cheynis, B.; Chiavassa, E.; Cicalo, C.; Comets, M.P.; Constans, N.; Constantinescu, S.; Contardo, D.; Cruz, J.; De Falco, A.; De Marco, N.; Dellacasa, G.; Devaux, A.; Dita, S.; Drapier, O.; Ducroux, L.; Espagnon, B.; Fargeix, J.; Ferreira, R.; Filippov, S.N.; Fleuret, F.; Force, P.; Gallio, M.; Gavrilov, Y.K.; Gerschel, C.; Giubellino, P.; Golubeva, M.B.; Gonin, M.; Gorodetzky, P.; Grigorian, A.A.; Grossiord, J.Y.; Guber, F.F.; Guichard, A.; Gulkanyan, H.; Hakobyan, R.; Haroutunian, R.; Idzik, M.; Jouan, D.; Karavitcheva, T.L.; Kluberg, L.; Kossakowski, R.; Kurepin, A.B.; Landau, G.; Le Bornec, Y.; Lourenco, C.; Luquin, L.; Macciotta, P.; Mac Cormick, M.; Mandry, R.; Marzari-Chiesa, A.; Masera, M.; Masoni, A.; Mehrabyan, S.; Monteno, M.; Mourgues, S.; Musso, A.; Ohlsson-Malek, F.; Petiau, P.; Piccotti, A.; Pizzi, J.R.; Prado da Silva, W.L.; Puddu, G.; Quintans, C.; Racca, C.; Ramello, L.; Ramos, S.; Rato-Mendes, P.; Riccati, L.; Romana, A.; Ropotar, I.; Saturnini, P.; Scomparin, E.; Serci, S.; Shahoyan, R.; Silva, S.; Sitta, M.; Soave, C.; Sonderegger, P.; Tarrago, X.; Topilskaya, N.S.; Usai, G.L.; Varela, J.; Vercellin, E.; Villatte, L.

1999-01-01

The study of muon pairs in the mass region 1.5 μμ 2 in 450 GeV/c p-A, 200 GeV/nucleon S-U and 158 GeV/nucleon Pb-Pb collisions is presented. In p-A interactions, the dimuon signal mass spectra are well described by a superposition of Drell-Yan and charmed meson semi-leptonic decay contributions, in agreement with previous experiments when considering a linear A dependence. In nucleus-nucleus reactions, taking only into account these two physical ingredients, a dimuon enhancement both with increasing A·B and centrality is observed

Nucleus and nucleus-cytoskeleton connections in 3D cell migration

Energy Technology Data Exchange (ETDEWEB)

Liu, Lingling, E-mail: liulingling2012@163.com; Luo, Qing, E-mail: qing.luo@cqu.edu.cn; Sun, Jinghui, E-mail: sunjhemail@163.com; Song, Guanbin, E-mail: song@cqu.edu.cn

2016-10-15

Cell migration plays an important role in many physiological and pathological settings, ranging from embryonic development to cancer metastasis. Currently, accumulating data suggest that cells migrating in three-dimensional (3D) environments show well-defined differences compared to their well-established two-dimensional (2D) counterparts. During 3D migration, the cell body and nucleus must deform to allow cellular passage through the available spaces, and the deformability of the relatively rigid nucleus may constitute a limiting step. Here, we highlight the key evidence regarding the role of the nuclear mechanics in 3D migration, including the molecular components that govern the stiffness of the nucleus and review how the nuclear dynamics are connected to and controlled by cytoskeleton-based migration machinery. Intriguingly, nuclear movement must be coordinated with the cytoskeletal dynamics at the leading and trailing edges, which in turn impact the cytoplasmic dynamics that affect the migration efficiency. Thus, we suggest that alterations in the nuclear structure may facilitate cellular reorganizations that are necessary for efficient migration. - Graphical abstract: Schematic representations of a cell migrating on a 2D substrate and a cell migrating in a 3D extracellular matrix environment. (A) Nucleus-cytoskeleton connections are essential to 3D migration. Mechanical signals are transduced by integrins at the cell surface and channeled to cytoskeletal proteins, which generates prestress. The nucleus-cytoskeleton connections can either act as a stable skeleton to anchor the nuclei or provide active force to move the nuclei. The LINC complex is responsible for the nucleo-cytoskeletal coupling. Nesprins connect the cytoskeletal proteins to the inner nuclear membrane proteins SUN1 and SUN2. The SUN proteins connect to the lamins that form the lamina, which attaches to the chromatin. This physical connectivity transmits the mechanical signals from receptors at

Nucleus and nucleus-cytoskeleton connections in 3D cell migration

International Nuclear Information System (INIS)

Liu, Lingling; Luo, Qing; Sun, Jinghui; Song, Guanbin

2016-01-01

Cell migration plays an important role in many physiological and pathological settings, ranging from embryonic development to cancer metastasis. Currently, accumulating data suggest that cells migrating in three-dimensional (3D) environments show well-defined differences compared to their well-established two-dimensional (2D) counterparts. During 3D migration, the cell body and nucleus must deform to allow cellular passage through the available spaces, and the deformability of the relatively rigid nucleus may constitute a limiting step. Here, we highlight the key evidence regarding the role of the nuclear mechanics in 3D migration, including the molecular components that govern the stiffness of the nucleus and review how the nuclear dynamics are connected to and controlled by cytoskeleton-based migration machinery. Intriguingly, nuclear movement must be coordinated with the cytoskeletal dynamics at the leading and trailing edges, which in turn impact the cytoplasmic dynamics that affect the migration efficiency. Thus, we suggest that alterations in the nuclear structure may facilitate cellular reorganizations that are necessary for efficient migration. - Graphical abstract: Schematic representations of a cell migrating on a 2D substrate and a cell migrating in a 3D extracellular matrix environment. (A) Nucleus-cytoskeleton connections are essential to 3D migration. Mechanical signals are transduced by integrins at the cell surface and channeled to cytoskeletal proteins, which generates prestress. The nucleus-cytoskeleton connections can either act as a stable skeleton to anchor the nuclei or provide active force to move the nuclei. The LINC complex is responsible for the nucleo-cytoskeletal coupling. Nesprins connect the cytoskeletal proteins to the inner nuclear membrane proteins SUN1 and SUN2. The SUN proteins connect to the lamins that form the lamina, which attaches to the chromatin. This physical connectivity transmits the mechanical signals from receptors at

CT classification of small thalamic hemorrhages. Topographic localization and clinical manifestation

Energy Technology Data Exchange (ETDEWEB)

Kawahara, Nobutaka; Kaneko, Mitsuo; Tanaka, Keisei; Muraki, Masaaki; Sato, Kengo (Hamamatsu Medical Center Hospital, Shizuoka (Japan))

1984-06-01

The thalamus is located deep in the cerebral hemispheres, and most of its nuclei have reciprocal fiber connections with specific areas over the cerebral cortex. Localized lesions in the thalamus, therefore, can cause specific neurological deficits, depending on their locations. From this point of view, we reviewed 110 cases, admitted over the past 7 years, with thalamic hemorrhages 37 (34%) of which were small hematomas less than 2 cm in diameter. These small hematomas could be divided into 4 types depending on their locations as follows: antero-lateral type, postero-lateral type, medial type, and dorsal type. Each type had the peculiar clinical features described below: 1) Postero-lateral Type (PL type, 28 cases, 76%): The original symptom was a sudden onset of moderate to severe sensori-motor deficits in most cases. The patients were mostly alert or only slightly confused. 2) Antero-lateral Type (AL type, 4 cases, 11%): The patients of this type first presented with sensori-motor disturbance and prefrontal signs. Both were generally mild and often disappeared early. 3) Medial Type (M type, 3 cases, 8%): The main symptom at onset was either a disturbance of consciousness or dementia. 4) Dorsal Type (D type, 2 cases, 5%): One patient with a right thalamic hematoma of this type showed geographical agnosia and visuo-constructive apraxia. The other patient, with a left-sided hematoma, exhibited transient clumsiness of the right hand and mild dysphasia. In our experience, the above classification of small hematomas clearly delineated the clinical symptoms and neurological signs of the different types; therefore, the symptoms and signs in larger hematoma could be explained by a combination of those of each type.

Unconditioned stimulus pathways to the amygdala: effects of lesions of the posterior intralaminar thalamus on foot-shock-induced c-Fos expression in the subdivisions of the lateral amygdala.

Science.gov (United States)

Lanuza, E; Moncho-Bogani, J; Ledoux, J E

2008-08-26

The lateral nucleus of the amygdala (LA) is a site of convergence for auditory (conditioned stimulus) and foot-shock (unconditioned stimulus) inputs during fear conditioning. The auditory pathways to LA are well characterized, but less is known about the pathways through which foot shock is transmitted. Anatomical tracing and physiological recording studies suggest that the posterior intralaminar thalamic nucleus, which projects to LA, receives both auditory and somatosensory inputs. In the present study we examined the expression of the immediate-early gene c-fos in the LA in rats in response to foot-shock stimulation. We then determined the effects of posterior intralaminar thalamic lesions on foot-shock-induced c-Fos expression in the LA. Foot-shock stimulation led to an increase in the density of c-Fos-positive cells in all LA subnuclei in comparison to controls exposed to the conditioning box but not shocked. However, some differences among the dorsolateral, ventrolateral and ventromedial subnuclei were observed. The ventrolateral subnucleus showed a homogeneous activation throughout its antero-posterior extension. In contrast, only the rostral aspect of the ventromedial subnucleus and the central aspect of the dorsolateral subnucleus showed a significant increment in c-Fos expression. The density of c-Fos-labeled cells in all LA subnuclei was also increased in animals placed in the box in comparison to untreated animals. Unilateral electrolytic lesions of the posterior intralaminar thalamic nucleus and the medial division of the medial geniculate body reduced foot-shock-induced c-Fos activation in the LA ipsilateral to the lesion. The number of c-Fos labeled cells on the lesioned side was reduced to the levels observed in the animals exposed only to the box. These results indicate that the LA is involved in processing information about the foot-shock unconditioned stimulus and receives this kind of somatosensory information from the posterior intralaminar

Physical meaning of the yields from hadron-nucleon, hadron-nucleus, and nucleus-nucleus collisions observed in experiments

International Nuclear Information System (INIS)

Strugalski, Z.

1995-01-01

A physical meaning of the outcomes from hadronic and nuclear collision processes at high energies is presented, as prompted experimentally. The fast and slow stages in hadron-nucleus collisions are distinguished. Hadrons are produced via intermediate objects observed in hadron-nucleus collisions. The intermediate objects may be treated as the groups of quarks or the quark bags. 37 refs

Serotonin gating of cortical and thalamic glutamate inputs onto principal neurons of the basolateral amygdala.

Science.gov (United States)

Guo, Ji-Dong; O'Flaherty, Brendan M; Rainnie, Donald G

2017-11-01

The basolateral amygdala (BLA) is a key site for crossmodal association of sensory stimuli and an important relay in the neural circuitry of emotion. Indeed, the BLA receives substantial glutamatergic inputs from multiple brain regions including the prefrontal cortex and thalamic nuclei. Modulation of glutamatergic transmission in the BLA regulates stress- and anxiety-related behaviors. Serotonin (5-HT) also plays an important role in regulating stress-related behavior through activation of both pre- and postsynaptic 5-HT receptors. Multiple 5-HT receptors are expressed in the BLA, where 5-HT has been reported to modulate glutamatergic transmission. However, the 5-HT receptor subtype mediating this effect is not yet clear. The aim of this study was to use patch-clamp recordings from BLA neurons in an ex vivo slice preparation to examine 1) the effect of 5-HT on extrinsic sensory inputs, and 2) to determine if any pathway specificity exists in 5-HT regulation of glutamatergic transmission. Two independent input pathways into the BLA were stimulated: the external capsule to mimic cortical input, and the internal capsule to mimic thalamic input. Bath application of 5-HT reversibly reduced the amplitude of evoked excitatory postsynaptic currents (eEPSCs) induced by stimulation of both pathways. The decrease was associated with an increase in the paired-pulse ratio and coefficient of variation of eEPSC amplitude, suggesting 5-HT acts presynaptically. Moreover, the effect of 5-HT in both pathways was mimicked by the selective 5-HT 1B receptor agonist CP93129, but not by the 5-HT 1A receptor agonist 8-OH DPAT. Similarly the effect of exogenous 5-HT was blocked by the 5-HT 1B receptor antagonist GR55562, but not affected by the 5-HT 1A receptor antagonist WAY 100635 or the 5-HT 2 receptor antagonists pirenperone and MDL 100907. Together these data suggest 5-HT gates cortical and thalamic glutamatergic inputs into the BLA by activating presynaptic 5-HT 1B receptors

Meson-nucleus potentials and the search for meson-nucleus bound states

Science.gov (United States)

Metag, V.; Nanova, M.; Paryev, E. Ya.

2017-11-01

Recent experiments studying the meson-nucleus interaction to extract meson-nucleus potentials are reviewed. The real part of the potentials quantifies whether the interaction is attractive or repulsive while the imaginary part describes the meson absorption in nuclei. The review is focused on mesons which are sufficiently long-lived to potentially form meson-nucleus quasi-bound states. The presentation is confined to meson production off nuclei in photon-, pion-, proton-, and light-ion induced reactions and heavy-ion collisions at energies near the production threshold. Tools to extract the potential parameters are presented. In most cases, the real part of the potential is determined by comparing measured meson momentum distributions or excitation functions with collision model or transport model calculations. The imaginary part is extracted from transparency ratio measurements. Results on K+ ,K0 ,K- , η ,η‧ , ω, and ϕ mesons are presented and compared with theoretical predictions. The interaction of K+ and K0 mesons with nuclei is found to be weakly repulsive, while the K- , η ,η‧ , ω and ϕ meson-nucleus potentials are attractive, however, with widely different strengths. Because of meson absorption in the nuclear medium the imaginary parts of the meson-nucleus potentials are all negative, again with a large spread. An outlook on planned experiments in the charm sector is given. In view of the determined potential parameters, the criteria and chances for experimentally observing meson-nucleus quasi-bound states are discussed. The most promising candidates appear to be the η and η‧ mesons.

Infant's bed climate and bedding in the Japanese home.

Science.gov (United States)

Nakamura Ikeda, Rie; Fukai, Kiyoko; Okamoto Mizuno, Kazue

2012-06-01

to assess the bed climate of infants in their homes in Japan. descriptive, exploratory, non-experimental research design. the data were collected at the participants' homes under normal circumstances. nineteen healthy infants between the ages of two and five months. Their mothers, who joined a parenting class organised by a maternity clinic in Okayama, Japan, consented to participate in this study. we visited the infants' homes and interviewed their mothers concerning the types and use of bedding. The temperature and relative humidity of the bed climate at the back and foot of the bedding, and in the room were measured every minute for four consecutive days. Differences among the bed climates measured during three seasons (spring, summer, and autumn) were assessed by one-way analysis of variance. The bed temperature was higher for infants than for adults. No significant difference in temperature was noted among the three seasons. The bed temperature was about 36.0°C when waterproof sheets and futon mattresses for children or adult were used. The average relative humidity of the bed climate at the back was highest in summer, followed by that in spring and autumn; the differences were significant. The use of waterproof sheets and futon mattresses for children in summer increased the relative humidity to 80% or more. The use of infant beds, sunoko drainboards, and cotton futon mattresses in summer was effective in reducing the bed humidity. these results suggest that nurse-midwives should advise the parents on comfortable bed climates for their infants, as well as how to select and use bedding for them. Copyright © 2010 Elsevier Ltd. All rights reserved.

Functional MRI for immediate monitoring stereotactic thalamotomy in a patient with essential tremor

International Nuclear Information System (INIS)

Hesselmann, Volker; Schaaf, Maike; Krug, Barbara; Lackner, Klaus; Maarouf, Mohammed; Hunsche, Stefan; Sturm, Volker; Lasek, Kathrin; Wedekind, Christoph

2006-01-01

The effect of stereotactic thalamotomy was assessed with pre- and postoperative functional magnetic resonance imaging (fMRI) under motor stimulation. A patient with unilateral essential tremor (ET) of the left arm underwent stereotactically guided thalamotomy of the right ventral intermediate thalamic nucleus (VIM). FMRI was done directly before and after surgery on a 1.5-Tesla scanner. The stimulation paradigm was maintainance of the affected arm in an extended position and hand clenching being performed in a block design manner. Statistical analysis was done with Brain Voyager 2000. After thalamotomy the tremor diminished completely. As a difference between the pre- and postoperative fMRI, a significant activation was found in the VIM contralateral to the activation site, adjacent to the inferior olivary nucleus contralateral to the activation site and in the dorsal cingulum. In conclusion, fMRI can detect the functional effect of thalamotomy for tremor treatment. Direct postoperative fMRI provides a sufficient method for estimating the effect of thalamotomy immediately after intervention. The importance of the intermediate thalamic nucleus and the olivary nucleus in tremor generation is supported by our findings. (orig.)

Capsular and thalamic infarction caused by tentorial herniation subsequent to head trauma

International Nuclear Information System (INIS)

Endo, M.; Ichikawa, F.; Miyasaka, Y.; Yada, K.; Ohwada, T.

1991-01-01

Five patients (4 male and 1 female) were observed to have capsular and thalamic infarction ascribed to descending transtentorial herniation (DTH) caused by head injury. A lucid interval immediately after the trauma and the presence of an epidural hematoma (EDH) characterized all five case. The low attenuation implicated the perforating arteries, that is the anterior thalamoperforating and anterior choroidal arteries, suggesting infarcted regions caused by occlusion of these arteries. Findings in the present study suggest that arterial occlusion in closed head injury may result from DTH. Moreover, infarction may be attributed to the delayed effects of injury. (orig./GDG)

Causal role of thalamic interneurons on brain state transitions: a study using a neural mass model implementing synaptic kinetics

Directory of Open Access Journals (Sweden)

Basabdatta Sen Bhattacharya

2016-11-01

Full Text Available Experimental studies on the Lateral Geniculate Nucleus (LGN of mammals and rodents show that the inhibitory interneurons (IN receive around 47.1% of their afferents from the retinal spiking neurons, and constitute around 20 - 25% of the LGN cell population. However, there is a definite gap in knowledge about the role and impact of IN on thalamocortical dynamics in both experimental and model-based research. We use a neural mass computational model of the LGN with three neural populations viz. IN, thalamocortical relay (TCR, thalamic reticular nucleus (TRN, to study the causality of IN on LGN oscillations and state-transitions. The synaptic information transmission in the model is implemented with kinetic modelling, facilitating the linking of low-level cellular attributes with high-level population dynamics. The model is parameterised and tuned to simulate both Local Field Potential (LFP of LGN and electroencephalogram (EEG of visual cortex in an awake resting state with eyes closed and dominant frequency within the alpha (8-13 Hz band. The results show that: First, the response of the TRN is suppressed in the presence of IN in the circuit; disconnecting the IN from the circuit effects a dramatic change in the model output, displaying high amplitude synchronous oscillations within the alpha band in both TCR and TRN. These observations conform to experimental reports implicating the IN as the primary inhibitory modulator of LGN dynamics in a cognitive state, and that reduced cognition is achieved by suppressing the TRN response. Second, the model validates steady state visually evoked potential response in humans corresponding to periodic input stimuli; however, when the IN is disconnected from the circuit, the output power spectra do not reflect the input frequency. This agrees with experimental reports underpinning the role of IN in efficient retino-geniculate information transmission. Third, a smooth transition from alpha to theta band is

Effective number of inelastically interacting nucleons in rare nucleus-nucleus production processes

International Nuclear Information System (INIS)

Korotkikh, V.L.; Lokhtin, I.P.

1992-01-01

A model of nucleus-nucleus interaction using one inelastic NN-interaction is suggested for the exclusive production processes with small cross-section. A-dependence nuclear coherent and incoherent production cross-section are predicted. 20 refs.; 4 figs

Corticotropin-Releasing Factor Receptors Modulate Oxytocin Release in the Dorsolateral Bed Nucleus of the Stria Terminalis (BNST in Male Rats

Directory of Open Access Journals (Sweden)

Daisy Martinon

2018-03-01

Full Text Available The neuropeptide oxytocin (OT plays an important role in the regulation of social and anxiety-like behavior. Our previous studies have shown that OT neurons send projections from the hypothalamus to the dorsolateral bed nucleus of the stria terminalis (BNSTdl, a forebrain region critically involved in the modulation of anxiety-like behavior. Importantly, these OT terminals in the BNSTdl express presynaptic corticotropin releasing factor (CRF receptor type 2 (CRFR2. This suggests that CRFR2 might be involved in the modulation of OT release. To test this hypothesis, we measured OT content in microdialysates collected from the BNSTdl of freely-moving male Sprague-Dawley rats following the administration of a selective CRFR2 agonist (Urocortin 3 or antagonist (Astressin 2B, As2B. To determine if type 1 CRF receptors (CRFR1 are also involved, we used selective CRFR1 antagonist (NBI35965 as well as CRF, a putative ligand of both CRFR1 and CRFR2. All compounds were delivered directly into the BNSTdl via reverse dialysis. OT content in the microdialysates was measured with highly sensitive and selective radioimmunoassay. Blocking CRFR2 with As2B caused an increase in OT content in BNSTdl microdialysates, whereas CRFR2 activation by Urocortin 3 did not have an effect. The As2B-induced increase in OT release was blocked by application of the CRFR1 antagonist demonstrating that the effect was dependent on CRFR1 transmission. Interestingly, CRF alone caused a delayed increase in OT content in BNSTdl microdialysates, which was dependent on CRF2 but not CRF1 receptors. Our results suggest that members of the CRF peptide family modulate OT release in the BNSTdl via a fine-tuned mechanism that involves both CRFR1 and CRFR2. Further exploration of mechanisms by which endogenous OT system is modulated by CRF peptide family is needed to better understand the role of these neuropeptides in the regulation of anxiety and the stress response.

Double folding model of nucleus-nucleus potential: formulae, iteration method and computer code

International Nuclear Information System (INIS)

Luk'yanov, K.V.

2008-01-01

Method of construction of the nucleus-nucleus double folding potential is described. Iteration procedure for the corresponding integral equation is presented. Computer code and numerical results are presented

Recovery of stress-impaired social behavior by an antagonist of the CRF binding protein, CRF6-33, in the bed nucleus of the stria terminalis of male rats.

Science.gov (United States)

Vasconcelos, Mailton; Stein, Dirson J; Albrechet-Souza, Lucas; Miczek, Klaus A; de Almeida, Rosa Maria M

2018-01-09

Social stress is recognized to promote the development of neuropsychiatric and mood disorders. Corticotropin releasing factor (CRF) is an important neuropeptide activated by social stress, and it contributes to neural and behavioral adaptations, as indicated by impaired social interactions and anhedonic effects. Few studies have focused on the role of the CRF binding protein (CRFBP), a component of the CRF system, and its activity in the bed nucleus of stria terminalis (BNST), a limbic structure connecting amygdala and hypothalamus. In this study, animals' preference for sweet solutions was examined as an index of stress-induced anhedonic responses in Wistar rats subjected to four brief intermittent episodes of social defeat. Next, social approach was assessed after local infusions of the CRFBP antagonist, CRF fragment 6-33 (CRF 6-33 ) into the BNST. The experience of brief episodes of social defeat impaired social approach behaviors in male rats. However, intra-BNST CRF 6-33 infusions restored social approach in stressed animals to the levels of non-stressed rats. CRF 6-33 acted selectively on social interaction and did not alter general exploration in nether stressed nor non-stressed rats. These findings suggest that BNST CRFBP is involved in the modulation of anxiety-like responses induced by social stress. Copyright © 2018 Elsevier B.V. All rights reserved.

Bed Bugs

Science.gov (United States)

Prevent, identify, and treat bed bug infestations using EPA’s step-by-step guides, based on IPM principles. Find pesticides approved for bed bug control, check out the information clearinghouse, and dispel bed bug myths.

Theory of and effects from elastoplasticity in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Noerenberg, W.; Technische Hochschule Darmstadt

1985-02-01

Elastoplasticity of finite Fermi systems results from a coherent coupling between collective and intrinsic degrees of freedom and subsequent equilibration essentially due to two-body collisions. Within a non-markovian transport-theoretical approach referred to as dissipative diabatic dynamics (DDD), elastoplastical forms the link between giant vibrations and overdamped motion of nuclear. Obersvable effects resulting from this non-markovian behaviour in nucleus-nucleus collisions are discussed. (orig.)

Study of η-nucleus interaction through the formation of η-nucleus ...

Indian Academy of Sciences (India)

Answer to this question will deeply enrich our understanding of -nucleus interaction which is not so well-understood. We review the experimental efforts for the search of -mesic nuclei and describe the physics motivation behind it. We present the description of an experiment for the search of -nucleus bound state using ...

Efferent connections and nigral afferents of the nucleus accumbens septi in the rat

Energy Technology Data Exchange (ETDEWEB)

Nauta, W J.H.; Smith, G P; Faull, R L.M.; Domesick, V B [Massachusetts Inst. of Tech., Cambridge (USA). Dept. of Psychology

1978-01-01

The results of this study by the methods of autoradiographic fiber-tracing and retrograde cell-labelling confirm earlier reports of accumbens projections to the globus pallidus and to dorsal strata of the medial half of the substantia nigra. Also in accord with previous autoradiographic evidence, sparser projections could be traced to a variety of subcortical structures implicated in the circuitry of the limbic system: bed nucleus of the stria terminalis, septum, preoptic region, hypothalamus, ventral tegmental area, nuclei paratenialis and mediodorsalis thalami, and lateral habenular nucleus. Contrary to earlier reports, striatopallidal fibers from the accumbens were found to be distributed largely to the subcommissural part of the external pallidal segment and to avoid almost entirely the internal pallidal segment. Mesencephalic projections from the accumbens largely coincide with those from the preoptic region and hypothalamus; like the latter they prominantly involve the region of the out-lying nigral cell groups A10 and A8 and extend caudally beyond the nigral complex to the cuneiform and parabrachial regions of the tegmentum as well as to caudoventral parts of the central grey substance. Horseradish peroxidase injected into the nucleus accumbens labels numerous neurons in the region of cell group A10 and in the supralemniscal 'retrorubral nucleus', but only sporadic cells in the pars compacta of the substantia nigra proper. It thus appears that the accumbens projects to a region of the nigral complex considerably larger than that from which it receives nigrostriatal fibers, and hence, that the nigro-striato-nigral circuit associated with the accumbens is not organized in a mode of simple point-for-point reciprocity. The problem of delimiting the accumbens from the rest of the striatum is examined by comparing cases of tracer injection into various discrete loci within the ventral zone of the striatum.

Bed agglomeration characteristics of palm shell and corncob combustion in fluidized bed

International Nuclear Information System (INIS)

Chaivatamaset, Pawin; Sricharoon, Panchan; Tia, Suvit

2011-01-01

Bed particle agglomeration was studied experimentally in an atmospheric laboratory scale fluidized bed combustor using quartz sand as bed material. Palm shell and corncob were tested. The objectives of the study were (i) to describe the contributions of the biomass ash properties and the operating conditions on the bed agglomeration tendency in term of the bed defluidization time (t def ) and the extent of potassium accumulation in the bed (K/Bed) and (ii) to further elucidate the ash inorganic behaviors and the governing bed agglomeration mechanisms. Defluidization caused by the bed agglomeration was experienced in all experiments during combustion of these biomasses, as a consequence of the presence of potassium in biomass. The experimental results indicated that biomass ash characteristics were the significant influence on the bed agglomeration. The increasing bed temperature, bed particle size and static bed height and the decreasing fluidizing air velocity enhanced the bed agglomeration tendency. The SEM/EDS analyses on the agglomerates confirmed that the agglomeration was attributed to the formation of potassium silicate liquid enriched on the surface of quartz sand particles in conjunction with the high surface temperature of the burning biomass char particles. Thermodynamic examination based on the phase diagram analysis confirmed that the molten phase formation was responsible for the agglomeration. In this study, the high molten ash fraction resulting from the high potassium content in biomass promoted the agglomeration and thus defluidization. - Highlights: → Palm shell and corncob of Thailand are tested their bed agglomeration behaviors during fluidized bed combustion. → The increase of bed temperature, bed particle size and static bed height and the decrease of air velocity enhance bed agglomeration. → The formation of ash derived potassium silicate melts enriched on sand surface is the key process. → The collision between char and sand

The characteristics of bed agglomeration during fluidized bed combustion of eucalyptus bark

International Nuclear Information System (INIS)

Chaivatamaset, Pawin; Tia, Suvit

2015-01-01

The bed agglomeration behaviors were investigated experimentally when eucalyptus bark was burning tested in a laboratory scale fluidized bed reactor. The focuses of this work were the influences of operating conditions and bed materials on the bed agglomeration tendency and the elucidation in the behaviors of fuel inorganic elements and the governing mode of the agglomeration. It was found that the defluidization caused by the bed agglomeration was clearly detectable from the decrease in measured bed pressure. The growth of bed particle and accumulation of agglomerates during combustion provided the partial to complete defluidization. The defluidization was promoted by the increase of bed temperature and bed particle size, and the decrease of fluidizing air velocity. The SEM-EDS analyses revealed that the bed agglomeration was mainly attributed to the formation of potassium silicate compounds as liquid phase during the combustion. This was initiated by the chemical reaction between the bed particle and the released ash constituents. In this study, the inorganic migration from fuel particle to bed particle was likely dominated by the condensation/reaction. The thermodynamic examination by ternary phase diagram analysis corroborated that the liquid phase formation of the ash derived materials controlled the agglomeration. The alumina sand prevented the bed agglomeration since it was inactive in the formation of viscous molten substances during combustion at the observed temperatures. - Highlights: • The behaviors of bed agglomeration were studied during the fluidized bed combustion of eucalyptus bark. • The increase in bed temperature and sand size, and the decrease of air velocity promoted bed defluidization. • The formation of molten potassium silicate compounds conduced to the bed agglomeration. • Condensation/reaction was the dominant inorganic migration mechanism from fuel particle to bed particle. • The alumina sand prevented effectively the bed

Consistency and diversity of spike dynamics in the neurons of bed nucleus of stria terminalis of the rat: a dynamic clamp study.

Directory of Open Access Journals (Sweden)

Attila Szücs

Full Text Available Neurons display a high degree of variability and diversity in the expression and regulation of their voltage-dependent ionic channels. Under low level of synaptic background a number of physiologically distinct cell types can be identified in most brain areas that display different responses to standard forms of intracellular current stimulation. Nevertheless, it is not well understood how biophysically different neurons process synaptic inputs in natural conditions, i.e., when experiencing intense synaptic bombardment in vivo. While distinct cell types might process synaptic inputs into different patterns of action potentials representing specific "motifs" of network activity, standard methods of electrophysiology are not well suited to resolve such questions. In the current paper we performed dynamic clamp experiments with simulated synaptic inputs that were presented to three types of neurons in the juxtacapsular bed nucleus of stria terminalis (jcBNST of the rat. Our analysis on the temporal structure of firing showed that the three types of jcBNST neurons did not produce qualitatively different spike responses under identical patterns of input. However, we observed consistent, cell type dependent variations in the fine structure of firing, at the level of single spikes. At the millisecond resolution structure of firing we found high degree of diversity across the entire spectrum of neurons irrespective of their type. Additionally, we identified a new cell type with intrinsic oscillatory properties that produced a rhythmic and regular firing under synaptic stimulation that distinguishes it from the previously described jcBNST cell types. Our findings suggest a sophisticated, cell type dependent regulation of spike dynamics of neurons when experiencing a complex synaptic background. The high degree of their dynamical diversity has implications to their cooperative dynamics and synchronization.

Synaptic Plasticity in the Bed Nucleus of the Stria Terminalis: Underlying Mechanisms and Potential Ramifications for Reinstatement of Drug- and Alcohol-Seeking Behaviors.

Science.gov (United States)

Harris, Nicholas A; Winder, Danny G

2018-06-13

The bed nucleus of the stria terminalis (BNST) is a component of the extended amygdala that shows significant changes in activity and plasticity through chronic exposure to drugs and stress. The region is critical for stress- and cue-induced reinstatement of drug-seeking behaviors and is thus a candidate region for the plastic changes that occur in abstinence that prime addicted patients for reinstatement behaviors. Here, we discuss the various forms of long-term potentiation (LTP) and long-term depression (LTD) in the rodent BNST and highlight the way that these changes in excitatory transmission interact with exposure to alcohol and other drugs of abuse, as well as other stressors. In addition, we highlight potential areas for future research in this area, including investigating input- and cell-specific bidirectional changes in activity. As we continue to accrue foundational knowledge in the mechanisms and effects of plasticity in the BNST, molecular targets and treatment strategies that are relevant to reinstatement behaviors will also begin to emerge. Here, we briefly discuss the effects of catecholamine receptor modulators on synaptic plasticity in the BNST due to the role of norepinephrine in LTD and dopamine on the short-term component of LTP as well as the role that signaling at these receptors plays in reinstatement of drug- and alcohol-seeking behaviors. We hope that insights gained on the specific changes in plasticity that occur within the BNST during abstinence from alcohol and other drugs of abuse will provide insight into the biological underpinnings of relapse behavior in human addicts and inform future treatment modalities for addiction that tackle this complex biological problem.

Quark matter formation in high energy nucleus-nucleus collisions - predictions and observations

International Nuclear Information System (INIS)

Otterlund, I.

1983-01-01

In this talk I give a short summary of the recent discussion around predictions and possible observations of quark-gluon plasma and fireballs in ultrarelativistic nucleus-nucleus collisions. In particular this talk is focused on heavy ion reactions at 200 A GeV. (orig./HSI)

The intercalatus nucleus of Staderini.

Science.gov (United States)

Cascella, Marco

2016-01-01

Rutilio Staderini was one of the leading Italian anatomists of the twentieth century, together with some scientists, such as Giulio Chiarugi, Giovanni Vitali, and others. He was also a member of a new generation of anatomists. They had continued the tradition of the most famous Italian scientists, which started from the Renaissance up until the nineteenth century. Although he carried out important studies of neuroanatomy and comparative anatomy, as well as embryology, his name is rarely remembered by most medical historians. His name is linked to the nucleus he discovered: the Staderini nucleus or intercalated nucleus, a collection of nerve cells in the medulla oblongata located lateral to the hypoglossal nucleus. This article focuses on the biography of the neuroanatomist as well as the nucleus that carries his name and his other research, especially on comparative anatomy and embryology.

The Safety of Hospital Beds: Ingress, Egress, and In-Bed Mobility.

Science.gov (United States)

Morse, Janice M; Gervais, Pierre; Pooler, Charlotte; Merryweather, Andrew; Doig, Alexa K; Bloswick, Donald

2015-01-01

To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients' ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients' use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated.

Dynamics of hadronization in ultra-relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Friman, B.L.

1986-01-01

One of the main problems in the search for quark-gluon plasma in ultra-relativistic nucleus-nucleus collisions is finding a reliable signature for deconfinement. Several signatures have been suggested, e.g., dileptons with a spectrum characteristic of the plasma, an increase in the number of strange particles and effects due to the hadronization of the plasma. In this talk I will describe some recent work on the effects of the hadronization transition in the central rapidity region within the hydrodynamic model of Bjorken, Kajantie and McLerran. (orig.)

Thalamic metabolic abnormalities in patients with Huntington's disease measured by magnetic resonance spectroscopy

International Nuclear Information System (INIS)

Casseb, R.F.; Castellano, G.; Ruocco, H.H.

2013-01-01

Huntington's disease (HD) is a neurologic disorder that is not completely understood; its fundamental physiological mechanisms and chemical effects remain somewhat unclear. Among these uncertainties, we can highlight information about the concentrations of brain metabolites, which have been widely discussed. Concentration differences in affected, compared to healthy, individuals could lead to the development of useful tools for evaluating the progression of disease, or to the advance of investigations of different/alternative treatments. The aim of this study was to compare the thalamic concentration of metabolites in HD patients and healthy individuals using magnetic resonance spectroscopy. We used a 2.0-Tesla magnetic field, repetition time of 1500 ms, and echo time of 135 ms. Spectra from 40 adult HD patients and 26 control subjects were compared. Quantitative analysis was performed using the LCModel method. There were statistically significant differences between HD patients and controls in the concentrations of N-acetylaspartate+N-acetylaspartylglutamate (NAA+NAAG; t-test, P,0.001), and glycerophosphocholine+phosphocholine (GPC+PCh; t-test, P=0.001) relative to creatine+phosphocreatine (Cr+PCr). The NAA+NAAG/Cr+PCr ratio was decreased by 9% and GPC+PCh/Cr+PCr increased by 17% in patients compared with controls. There were no correlations between the concentration ratios and clinical features. Although these results could be caused by T1 and T2 changes, rather than variations in metabolite concentrations given the short repetition time and long echo time values used, our findings point to thalamic dysfunction, corroborating prior evidence. (author)

The picture of the nuclei disintegration mechanism - from hadron-nucleus and nucleus-nucleus collisions experimental investigations at high energies

International Nuclear Information System (INIS)

Strugalska-Gola, E.; Strugalski, Z.; Chmielowski, W.

1997-01-01

The mechanism of the nuclei disintegration process in collisions of high-energy hadrons with nuclei is revealed experimentally. The disintegration appears as a complicated nuclear process developing in time and space in intranuclear matter, consisting at least of three stages which last together about 10 -24 - 10 -17 s after the impact. At the first stage, which lasts about 10 -24 - 10 -22 s, fast nucleons are densely emitted and the target-nucleus is locally damaged. At the second stage, lasting about 10 -22 - 10 -1 7 s, the damaged and unstable residual target nucleus uses to evaporate light fragments - mainly nucleons, deuterons, tritons, α-particles. At the final stage, the residual target-nucleus uses to split sometimes into two or more nuclear fragments

Successive neuron loss in the thalamus and cortex in a mouse model of infantile neuronal ceroid lipofuscinosis.

Science.gov (United States)

Kielar, Catherine; Maddox, Lucy; Bible, Ellen; Pontikis, Charlie C; Macauley, Shannon L; Griffey, Megan A; Wong, Michael; Sands, Mark S; Cooper, Jonathan D

2007-01-01

Infantile neuronal ceroid lipofuscinosis (INCL) is caused by deficiency of the lysosomal enzyme, palmitoyl protein thioesterase 1 (PPT1). We have investigated the onset and progression of pathological changes in Ppt1 deficient mice (Ppt1-/-) and the development of their seizure phenotype. Surprisingly, cortical atrophy and neuron loss occurred only late in disease progression but were preceded by localized astrocytosis within individual thalamic nuclei and the progressive loss of thalamic neurons that relay different sensory modalities to the cortex. This thalamic neuron loss occurred first within the visual system and only subsequently in auditory and somatosensory relay nuclei or the inhibitory reticular thalamic nucleus. The loss of granule neurons and GABAergic interneurons followed in each corresponding cortical region, before the onset of seizure activity. These findings provide novel evidence for successive neuron loss within the thalamus and cortex in Ppt1-/- mice, revealing the thalamus as an important early focus of INCL pathogenesis.

Proton rapidity distribution in nucleus-nucleus collisions at high energy

International Nuclear Information System (INIS)

Liu, F.H.

2002-01-01

The proton rapidity distributions in nucleus-nucleus collisions at the Alternating Gradient Synchrotron (AGS) and the Super Proton Synchrotron (SPS) energies are analysed by the revised thermalized cylinder model. The calculated results are compared and found to he in agreement with the experimental data of Si-AI and Si-Pb collisions at 14.6 A GeV/c, Pb-Pb collisions at 158 A GeV/c, and S-S collisions at 200 A GeV/c. (Author)

ψ' and J/ψ suppression in high-energy nucleon-nucleus and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Wong, Cheuk-Yin.

1995-01-01

The observed features of ψ' to J/ψ suppression in pA and nucleus-nucleus collisions can be explained in terms of a two-component absorption model. For the hard component of the absorption due to the interaction of the produced c bar c systems with baryons at high relative energies, the absorption cross sections are insensitive to the radii of the c bar c systems, as described by the Additive Quark Model. For the soft component due to the low energy c bar c interactions with soft particles produced by other baryon-baryon collisions, the absorption cross sections are greater for ψ' than for J/ψ, because the breakup threshold for ψ' is much smaller than for ψ

Pharmacological manipulation of GABA activity in nucleus subpretectalis/interstitio-pretecto-subpretectalis (SP/IPS) impairs figure-ground discrimination in pigeons: Running head: SP/IPS in figure-ground segregation.

Science.gov (United States)

Acerbo, Martin J; Lazareva, Olga F

2018-05-15

Figure-ground segregation is a fundamental visual ability that allows an organism to separate an object from its background. Our earlier research has shown that nucleus rotundus (Rt), a thalamic nucleus processing visual information in pigeons, together with its inhibitory complex, nucleus subpretectalis/interstitio-pretecto-subpretectalis (SP/IPS), are critically involved in figure-ground discrimination (Acerbo et al., 2012; Scully et al., 2014). Here, we further investigated the role of SP/IPS by conducting bilateral microinjections of GABAergic receptor antagonist and agonists (bicuculline and muscimol, respectively) and non-NMDA glutamate receptor antagonist (CNQX) after the pigeons mastered figure-ground discrimination task. We used two doses of each drug (bicuculline: 0.1 mM and 0.05 mM; muscimol: 4.4 mM and 8.8 mM; CNQX: 2.15 mM and 4.6 mM) in a within-subject design, and alternated drug injections with baseline (ACSF). The order of injections was randomized across birds to reduce potential carryover effects. We found that a low dose of bicuculline produced a decrement on figure trials but not on background trials, whereas a high dose impaired performance on background trials but not on figure trials. Muscimol produced an equivalent, dose-dependent impairment on both types of trials. Finally, CNQX had no consistent effect at either dose. Together, these results further confirm our earlier hypothesis that inhibitory projections from SP to Rt modulate figure-ground discrimination, and suggest that the Rt and the SP/IPS provide a plausible substrate that could perform figure-ground segregation in avian brain. Copyright © 2018 Elsevier B.V. All rights reserved.

The Baryon Production and Baryon Number Transfer in Hadron-Hadron, Hadron-Nucleus and Nucleus-Nucleus Collisions

International Nuclear Information System (INIS)

Szymanski, P.

2006-09-01

This work concerns soft hadronic interactions which in the Standard Model carry most of the observable cross-section but are not amenable to quantitative predictions due to the very nature of the QCD (Theory of Strong Interactions). In the low momentum transfer region the evolving coupling constant caused perturbation theory to break down. In this situation better experimental understanding of the physics phenomena is needed. One aspect of the soft hadronic interactions will be discussed in this work: transfer of the baryon number from the initial to the final state of the interaction. The past experimental knowledge on this process is presented, reasons for its unsatisfactory status are discussed and condition necessary for improvement are outlined: that is experimental apparatus with superior performance over the full range of available interactions: hadron-hadron collision, hadron-nucleus and nucleus-nucleus interactions. A consistent model-independent picture of the baryon number transfer process emerging from the data on the full range of interactions is shown. It offers serious challenge to theory to provide quantitative and detailed explanation of the measurements. (author)

Production of strange and multistrange hadrons in nucleus-nucleus collisions at the SPS

Czech Academy of Sciences Publication Activity Database

Antinori, F.; Bakke, H.; Beusch, W.; Staroba, Pavel; Závada, Petr

1999-01-01

Roč. 661, - (1999), 130c-139c ISSN 0375-9474 Institutional research plan: CEZ:AV0Z1010920 Keywords : production * nucleus-nucleus collisions * hadrons * strangeness * model predictions Subject RIV: BF - Elementary Particles and High Energy Physics Impact factor: 2.088, year: 1999

7 CFR 2902.15 - Bedding, bed linens, and towels.

Science.gov (United States)

2010-01-01

... PROCUREMENT Designated Items § 2902.15 Bedding, bed linens, and towels. (a) Definition. (1) Bedding is that... minimum biobased content is 12 percent and shall be based on the amount of qualifying biobased carbon in..., and silk are not qualifying biobased feedstocks for the purpose of determining the biobased content of...

Mediodorsal Thalamic Neurons Mirror the Activity of Medial Prefrontal Neurons Responding to Movement and Reinforcement during a Dynamic DNMTP Task.

Science.gov (United States)

Miller, Rikki L A; Francoeur, Miranda J; Gibson, Brett M; Mair, Robert G

2017-01-01

The mediodorsal nucleus (MD) interacts with medial prefrontal cortex (mPFC) to support learning and adaptive decision-making. MD receives driver (layer 5) and modulatory (layer 6) projections from PFC and is the main source of driver thalamic projections to middle cortical layers of PFC. Little is known about the activity of MD neurons and their influence on PFC during decision-making. We recorded MD neurons in rats performing a dynamic delayed nonmatching to position (dDNMTP) task and compared results to a previous study of mPFC with the same task (Onos et al., 2016). Criterion event-related responses were observed for 22% (254/1179) of neurons recorded in MD, 237 (93%) of which exhibited activity consistent with mPFC response types. More MD than mPFC neurons exhibited responses related to movement (45% vs. 29%) and reinforcement (51% vs. 27%). MD had few responses related to lever presses, and none related to preparation or memory delay, which constituted 43% of event-related activity in mPFC. Comparison of averaged normalized population activity and population response times confirmed the broad similarity of common response types in MD and mPFC and revealed differences in the onset and offset of some response types. Our results show that MD represents information about actions and outcomes essential for decision-making during dDNMTP, consistent with evidence from lesion studies that MD supports reward-based learning and action-selection. These findings support the hypothesis that MD reinforces task-relevant neural activity in PFC that gives rise to adaptive behavior.

Particle production in high energy nucleus--nucleus experiments at Berkeley

International Nuclear Information System (INIS)

Schroeder, L.S.

1976-09-01

A review of high energy nucleus-nucleus experiments performed at the Berkeley Bevalac is presented. Earlier results on projectile and target fragmentation and pion production are briefly summarized. More recent results on Coulomb effects in projectile fragmentation, heavy ion total cross-sections, γ-ray production, and charged particle multiplicities are presented. Also, recent experiments which may shed light on phenomena arising from the central collision of two energetic nuclei, including recent evidence for and against the observation of nuclear shock waves, are reviewed

Evaluation of a clay-based acidic bedding conditioner for dairy cattle bedding.

Science.gov (United States)

Proietto, R L; Hinckley, L S; Fox, L K; Andrew, S M

2013-02-01

This study investigated the effects of a clay-based acidic bedding conditioner on sawdust bedding pH, dry matter (DM), environmental pathogen counts, and environmental bacterial counts on teat ends of lactating dairy cows. Sixteen lactating Holstein cows were paired based on parity, days in milk, milk yield, and milk somatic cell count, and were negative for the presence of an intramammary pathogen. Within each pair, cows were randomly assigned to 1 of 2 treatments with 3-wk periods in a crossover design. Treatment groups consisted of 9 freestalls per group bedded with either untreated sawdust or sawdust with a clay-based acidic bedding conditioner, added at 3- to 4-d intervals over each 21-d period. Bedding and teat ends were aseptically sampled on d 0, 1, 2, 7, 14, and 21 for determination of environmental bacterial counts. At the same time points, bedding was sampled for DM and pH determination. The bacteria identified in the bedding material were total gram-negative bacteria, Streptococcus spp., and coliform bacteria. The bacteria identified on the teat ends were Streptococcus spp., coliform bacteria, and Klebsiella spp. Teat end score, milk somatic cell count, and intramammary pathogen presence were measured weekly. Bedding and teat cleanliness, environmental high and low temperatures, and dew point data were collected daily. The bedding conditioner reduced the pH, but not the DM, of the sawdust bedding compared with untreated sawdust. Overall environmental bacterial counts in bedding were lower for treated sawdust. Total bacterial counts in bedding and on teat ends increased with time over both periods. Compared with untreated sawdust, the treated bedding had lower counts of total gram-negative bacteria and streptococci, but not coliform counts. Teat end bacterial counts were lower for cows bedded on treated sawdust for streptococci, coliforms, and Klebsiella spp. compared with cows bedded on untreated sawdust. The clay-based acidic bedding conditioner

Kaonic nuclei and kaon-nucleus interactions

CERN Document Server

Ikuta, K; Masutani, K

2002-01-01

Although kaonic atoms provide valuable information concerning the K sup - -nucleus interaction at low energies, they cannot fully determine the K sup - - nucleus optical potential. We demonstrate that K sup - nuclear bound states, if they exist, can be useful in investigating the K sup - -nucleus interaction, especially in the interior of the nucleus. In order to show this possibility, we calculate the double differential cross sections for (K sup - , P) using the Green function method. (author)

Prognosis of thalamic hemorrhage with special reference to the level of consciousness and CT findings on admission

International Nuclear Information System (INIS)

Yamamoto, Toshimasa; Tanahashi, Norio; Nara, Masaharu; Takenaka, Nobuo

1991-01-01

The prognosis of thalamic hemorrhage was studied on the basis of neurological gradings on admission, mode of extension and hematoma size on brain CT. The subjects were 126 patients with thalamic hemorrhage who were admitted to Ashikaga Red Cross Hospital during the past ten years. Among the subjects, 120 patients (ages 64±10 yr; mean ±SD) were treated with conservative therapy, and 6 patients (ages 59±10 yr) with surgical therapy (ventricular drainage). Brain CT scans were done within 48 hours after onset in all patients. Neurological gradings, brain CT classification and prognosis were investigated according to the criteria of the Japanese Conference on Surgery for Cerebral Stroke. The results of conservative therapy were as follows: (1) In the grade I group on the neurological gradings, 29 of the 39 patients (74%) recovered to full work or an independent life, and none of them died. In the grade IV and V groups, mortality rate was 86%. (2) The prognosis was more unfavorable in type III than in types I and II on the CT classification. Twenty-six of the 36 patients (73%) with type I-a recovered to full work or an independent life. Twenty-five of the 34 patients (74%) with the type III-b died. (3) Only 4 of the 75 patients (5%) with less than 10 ml of hematoma volume died. In contrast, all 14 patients with more than 25 ml of hematoma volume died. (4) The mortality rate among patients with ventricular rupture (47%) was significantly higher than that among patients without ventricular rupture (2%) (p<0.001). (5) The mortality rate of patients with acute hydrocephalus (83%) was significantly higher than that of patients without acute hydrocephalus (20%) (p<0.001). From the above results, it is suggested that neurological grading, brain CT classification, hematoma volume, ventricular rupture and acute hydrocephalus are important prognostic factors for thalamic hemorrhage. (author)

Role of thalamic projection in NMDA receptor-induced disruption of cortical slow oscillation and short-term plasticity

Directory of Open Access Journals (Sweden)

Tamás eKiss

2011-04-01

Full Text Available NMDA receptor (NMDAR antagonists, such as phencyclidine, ketamine or dizocilpine (MK-801 are commonly used in psychiatric drug discovery in order to model several symptoms of schizophrenia, including psychosis and impairments in working memory. In spite of the widespread use of NMDAR antagonists in preclinical and clinical studies, our understanding of the mode of action of these drugs on brain circuits and neuronal networks is still limited. In the present study spontaneous local field potential (LFP, multi- (MUA and single unit activity, and evoked potential, including paired-pulse facilitation (PPF in response to electrical stimulation of the ipsilateral subiculum were carried out in the medial prefrontal cortex (mPFC in urethane anesthetized rats. Systemic administration of MK-801 (0.05~mg/kg, i.v. decreased overall MUA, with a diverse effect on single unit activity, including increased, decreased or unchanged firing, and in line with our previous findings shifted delta frequency power of the LFP and disrupted PPF (Kiss et al., Int J Neuropsychopharmacol. 2010. In order to provide further insight to the mechanisms of action of NMDAR antagonists, MK-801 was administered intracranially into the mPFC and mediodorsal nucleus of the thalamus (MD. Microinjections of MK-801, but not physiological saline, localized into the MD evoked changes in both LFP parameters and PPF similar to the effects of systemically administered MK-801. Local microinjection of MK-801 into the mPFC was without effect on these parameters. Our findings indicate that the primary site of the action of systemic administration of NMDA receptor antagonists is unlikely to be the cortex. We presume that multiple neuronal networks, involving thalamic nuclei contribute to disrupted behavior and cognition following NMDA receptor blockade.

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.

The nucleus

International Nuclear Information System (INIS)

Marano, S.

1998-01-01

In 1911 E.Rutherford discovered the nucleus. Since then the nucleus has been investigated with more and more powerful tools but it remains the main field of study of nuclear physics. As it is impossible to take into account the interaction of all the nucleons, a theory based on the hypothesis that each nucleon undergoes an average interaction force has been set up. 2 representations have emerged: the Skyrme force and the Gogny force. Both representations match experimental results but are unable to describe fission yields or the multi-fragmentation of very hot nuclei. The mean-field theory can predict the shape of the nuclei according to its energy level. An experimental program involving the Vivitron accelerator and the Euroball detector is due to begin to validate it. By bombarding targets with exotic nuclei nuclear physicists detect new structures and test their collision models. About ten years ago nuclear halos were observed with lithium 11 nuclei. In this nucleus 2 neutrons move in a space larger than the nucleus itself. This discovery has triggered the elaboration of new theories based on nuclear clusters. At very high temperatures the mean-field theory predicts that nuclear matter acts as a fluid. Following the nuclei temperature different ways of decay appear: first evaporation then multi-fragmentation and vaporization. This ultimate stage occurs around 100 milliard celsius degree temperature when the nuclei decays in a multitude of light particles. Isomeric states are studied and could be seen as a way of storing energy. In a very pedagogical way this article gives information to understand the challenges that face nuclear physics today and highlights the contributions of Cea in this field. (A.C.)

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

International Nuclear Information System (INIS)

Zuccoli, Giulio; Yannes, Michael Paul; Nardone, Raffaele; Bailey, Ariel; Goldstein, Amy

2015-01-01

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.)

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.)

Intrathalamic Mechanisms of Visual Attention

OpenAIRE

Mayo, J. Patrick

2009-01-01

The classical model of visual processing emphasizes the lateral geniculate nucleus (LGN) as the major intermediary between the retina and visual cortex. Yet, anatomical findings inspired Francis Crick to suggest an alternative model in which the thalamic reticular nucleus, which envelops the LGN, acts as the “guardian” of visual cortex by modulating LGN activity. Recent work by McAlonan and colleagues supports Crick's hypothesis, thereby enhancing our understanding of the early stages of visu...

Intrathalamic mechanisms of visual attention.

Science.gov (United States)

Mayo, J Patrick

2009-03-01

The classical model of visual processing emphasizes the lateral geniculate nucleus (LGN) as the major intermediary between the retina and visual cortex. Yet, anatomical findings inspired Francis Crick to suggest an alternative model in which the thalamic reticular nucleus, which envelops the LGN, acts as the "guardian" of visual cortex by modulating LGN activity. Recent work by McAlonan and colleagues supports Crick's hypothesis, thereby enhancing our understanding of the early stages of visual processing.

Aphasia following left thalamic hemorrhage

International Nuclear Information System (INIS)

Makishita, Hideo; Miyasaka, Motomaro; Tanizaki, Yoshio; Yanagisawa, Nobuo; Sugishita, Morihiro.

1984-01-01

We reported 7 patients with left thalamic hemorrhage in the chronic stage (from 1.5 months to 4.5 months), and described language disorders examined by Western Aphasia Battery (WAB) and measured cerebral blood flow by single photon emission CT. Examination of language by WAB revealed 4 aphasics out of 7 cases, and 3 patients had no language deficit. The patient with Wernicke's aphasia showed low density area only in the left posterior thalamus in X-ray CT, and revealed severe low blood flow area extending to left temporal lobe in emission CT. In the case with transcortical sensory aphasia, although X-ray CT showed no obvious low density area, emission CT revealed moderate low flow area in watershed area that involved the territory between posterior cerebral and middle cerebral arteries in the left temporooccipital region in addition to low blood flow at the left thalamus. In one of the two patients classified as anomic aphasia, whose score of repetition (8.4) was higher than that of comprehension (7.4), emission CT showed slight low flow area at the temporo-occipital region similarly as the case with transcortical sensory aphasia. In another case with anomic aphasia, scored 9 on both fluensy and comprehension subtests and 10 on repetition, there was wide low density area all over the left thalamus and midline shift to the right in X-ray CT, and emission CT showed severe low blood flow in the same region spreading widely toward the cerebral surface. On the other hand, in all of the 3 patients without aphasia, emission CT showed low flow region restricted to the left thalamus. (J.P.N.)

Dissipation in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Santanu Pal

1984-01-01

This paper deals with the mechanism of one- and two-body dissipations in nucleus-nucleus collisions. The average energy transferred to nuclear excitations is calculated using a time-dependent density matrix approach with lowest-order approximations. Considering the nuclei as Fermi gases, and using a gaussian-type NN interaction as the basic perturbation, simplified expressions are obtained for energy dissipations. These expressions are quite instructive to follow a number of interesting aspects of one- and two-body dissipations. It is theoretically observed that the memory time for the two-body dissipation is significantly smaller than that of one-body dissipation. A threshold-type dependence of the transferred energy on the relative velocity between the two nuclei is also observed. This threshold velocity is found to be related with the intrinsic nucleon kinetic energy for two-body dissipation and with the nuclear size for the one-body case. This observation further suggests that the total dissipated energy is shared between the two nuclei approximately in the ratio of their masses. The physical origin of these observations is also explained. Numerical calculations further illustrate some characteristic features of one- and two-body dissipations. (orig.)

Single nucleon emission in relativistic nucleus-nucleus reactions

International Nuclear Information System (INIS)

Anon.

1992-01-01

Significant discrepancies between theory and experiment have previously been noted for nucleon emission via electromagnetic processes in relativistic nucleus-nucleus collisions. The present work investigates the hypothesis that these discrepancies have arisen due to uncertainties about how to deduce the experimental electromagnetic cross section from the total measured cross section. An optical-model calculation of single neutron removal is added to electromagnetic cross sections and compared to the total experimental cross sections. Good agreement is found thereby resolving some of the earlier noted discrepancies. A detailed comparison to the recent work of Benesh, Cook, and Vary is made for both the impact parameter and the nuclear cross section. Good agreement is obtained giving an independent confirmation of the parameterized formulas developed by those authors

Strategic lesions in the anterior thalamic radiation and apathy in early Alzheimer's disease.

Directory of Open Access Journals (Sweden)

Mario Torso

Full Text Available Behavioural disorders and psychological symptoms of Dementia (BPSD are commonly observed in Alzheimer's disease (AD, and strongly contribute to increasing patients' disability. Using voxel-lesion-symptom mapping (VLSM, we investigated the impact of white matter lesions (WMLs on the severity of BPSD in patients with amnestic mild cognitive impairment (a-MCI.Thirty-one a-MCI patients (with a conversion rate to AD of 32% at 2 year follow-up and 26 healthy controls underwent magnetic resonance imaging (MRI examination at 3T, including T2-weighted and fluid-attenuated-inversion-recovery images, and T1-weighted volumes. In the patient group, BPSD was assessed using the Neuropsychiatric Inventory-12. After quantitative definition of WMLs, their distribution was investigated, without an a priori anatomical hypothesis, against patients' behavioural symptoms. Unbiased regional grey matter volumetrics was also used to assess the contribution of grey matter atrophy to BPSD.Apathy, irritability, depression/dysphoria, anxiety and agitation were shown to be the most common symptoms in the patient sample. Despite a more widespread anatomical distribution, a-MCI patients did not differ from controls in WML volumes. VLSM revealed a strict association between the presence of lesions in the anterior thalamic radiations (ATRs and the severity of apathy. Regional grey matter atrophy did not account for any BPSD.This study indicates that damage to the ATRs is strategic for the occurrence of apathy in patients with a-MCI. Disconnection between the prefrontal cortex and the mediodorsal and anterior thalamic nuclei might represent the pathophysiological substrate for apathy, which is one of the most common psychopathological symptoms observed in dementia.

Compensating for Thalamocortical Synaptic Loss in Alzheimer’s Disease

Directory of Open Access Journals (Sweden)

Kamal eAbuhassan

2014-06-01

Full Text Available The study presents a thalamocortical network model which oscillates within the alpha frequency band (8-13 Hz as recorded in the wakeful relaxed state with closed eyes to study the neural causes of abnormal oscillatory activity in Alzheimer’s disease (AD. Incorporated within the model are various types of cortical excitatory and inhibitory neurons, recurrently connected to thalamic and reticular thalamic regions with the ratios and distances derived from the mammalian thalamocortical system. The model is utilized to study the impacts of four types of connectivity loss on the model’s spectral dynamics. The study focuses on investigating degeneration of corticocortical, thalamocortical, corticothalamic and corticoreticular couplings, with an emphasis on the influence of each modelled case on the spectral output of the model. Synaptic compensation has been included in each model to examine the interplay between synaptic deletion and compensation mechanisms, and the oscillatory activity of the network. The results of power spectra and event related desynchronisation/synchronisation (ERD/S analyses show that the dynamics of the thalamic and cortical oscillations are significantly influenced by corticocortical synaptic loss. Interestingly, the patterns of changes in thalamic spectral activity are correlated with those in the cortical model. Similarly, the thalamic oscillatory activity is diminished after partial corticothalamic denervation. The results suggest that thalamic atrophy is a secondary pathology to cortical shrinkage in Alzheimer’s disease. In addition, this study finds that the inhibition from neurons in the thalamic reticular nucleus (RTN to thalamic relay (TCR neurons plays a key role in regulating thalamic oscillations; disinhibition disrupts thalamic oscillatory activity even though TCR neurons are more depolarized after being released from RTN inhibition. This study provides information that can be explored experimentally to

Direct projection from the suprachiasmatic nucleus to hypophysiotrophic corticotropin-releasing factor immunoreactive cells in the paraventricular nucleus of the hypothalamus demonstrated...

DEFF Research Database (Denmark)

Vrang, N.; Larsen, P.J.; Mikkelsen, J.D.

1995-01-01

Suprachiasmatic nucleus, paraventricular nucleus, circadian rhythms, phaseolus vulgaris-leucoagglutinin, corticotropin-releasing factor, dual immunocytochemistry......Suprachiasmatic nucleus, paraventricular nucleus, circadian rhythms, phaseolus vulgaris-leucoagglutinin, corticotropin-releasing factor, dual immunocytochemistry...

Clinical appraisal of stereotactic hematoma aspiration surgery for hypertensive thalamic hemorrhage; With respect to volume of the hematoma

Energy Technology Data Exchange (ETDEWEB)

Sasaki, Koji; Matsumoto, Keizo (Tokushima Univ. (Japan). School of Medicine)

1992-06-01

Three hundred and four patients with hypertensive thalamic hemorrhage were managed by medical treatment, ventricular drainage, or CT-controlled stereotactic aspiration surgery (AS). The therapeutic results of the 6-month outcome were analyzed and correlated with the volume of the hematoma. A hematoma volume of 20 ml was thought to be the critical size in determining whether the outcome would be favorable or unfavorable. Indications for AS are suggested as follows. In patients with a small-sized hematoma having a volume of less than 10 ml use of AS should be restricted to patients with severe paralysis or other neurological complications and the elderly (aged 70 years or older). For patients with a medium-sized hematoma having a volume between 10 ml and 20 ml, AS is indicated for patients having severe paralysis and disturbances of consciousness. For patients with a large-sized hematoma having a volume of 20 ml or more, AS increases not only the survival rate of patients but also reduces the number of bedridden patients. We conclude that AS opens up a new avenue of surgical treatment for hypertensive thalamic hemorrhage, which has been no indication for hematoma evacuation by conventional craniotomy. (author).

Sleep spindles are related to schizotypal personality traits and thalamic glutamine/glutamate in healthy subjects.

Science.gov (United States)

Lustenberger, Caroline; O'Gorman, Ruth L; Pugin, Fiona; Tüshaus, Laura; Wehrle, Flavia; Achermann, Peter; Huber, Reto

2015-03-01

Schizophrenia is a severe mental disorder affecting approximately 1% of the worldwide population. Yet, schizophrenia-like experiences (schizotypy) are very common in the healthy population, indicating a continuum between normal mental functioning and the psychosis found in schizophrenic patients. A continuum between schizotypy and schizophrenia would be supported if they share the same neurobiological origin. Two such neurobiological markers of schizophrenia are: (1) a reduction of sleep spindles (12-15 Hz oscillations during nonrapid eye movement sleep), likely reflecting deficits in thalamo-cortical circuits and (2) increased glutamine and glutamate (Glx) levels in the thalamus. Thus, this study aimed to investigate whether sleep spindles and Glx levels are related to schizotypal personality traits in healthy subjects. Twenty young male subjects underwent 2 all-night sleep electroencephalography recordings (128 electrodes). Sleep spindles were detected automatically. After those 2 nights, thalamic Glx levels were measured by magnetic resonance spectroscopy. Subjects completed a magical ideation scale to assess schizotypy. Sleep spindle density was negatively correlated with magical ideation (r = -.64, P .1). The common relationship of sleep spindle density with schizotypy and thalamic Glx levels indicates a neurobiological overlap between nonclinical schizotypy and schizophrenia. Thus, sleep spindle density and magical ideation may reflect the anatomy and efficiency of the thalamo-cortical system that shows pronounced impairment in patients with schizophrenia. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Serotonin projection patterns to the cochlear nucleus.

Science.gov (United States)

Thompson, A M; Thompson, G C

2001-07-13

The cochlear nucleus is well known as an obligatory relay center for primary auditory nerve fibers. Perhaps not so well known is the neural input to the cochlear nucleus from cells containing serotonin that reside near the midline in the midbrain raphe region. Although the specific locations of the main, if not sole, sources of serotonin within the dorsal cochlear nucleus subdivision are known to be the dorsal and median raphe nuclei, sources of serotonin located within other cochlear nucleus subdivisions are not currently known. Anterograde tract tracing was used to label fibers originating from the dorsal and median raphe nuclei while fluorescence immunohistochemistry was used to simultaneously label specific serotonin fibers in cat. Biotinylated dextran amine was injected into the dorsal and median raphe nuclei and was visualized with Texas Red, while serotonin was visualized with fluorescein. Thus, double-labeled fibers were unequivocally identified as serotoninergic and originating from one of the labeled neurons within the dorsal and median raphe nuclei. Double-labeled fiber segments, typically of fine caliber with oval varicosities, were observed in many areas of the cochlear nucleus. They were found in the molecular layer of the dorsal cochlear nucleus, in the small cell cap region, and in the granule cell and external regions of the cochlear nuclei, bilaterally, of all cats. However, the density of these double-labeled fiber segments varied considerably depending upon the exact region in which they were found. Fiber segments were most dense in the dorsal cochlear nucleus (especially in the molecular layer) and the large spherical cell area of the anteroventral cochlear nucleus; they were moderately dense in the small cell cap region; and fiber segments were least dense in the octopus and multipolar cell regions of the posteroventral cochlear nucleus. Because of the presence of labeled fiber segments in subdivisions of the cochlear nucleus other than the

Actomyosin contractility rotates the cell nucleus.

Science.gov (United States)

Kumar, Abhishek; Maitra, Ananyo; Sumit, Madhuresh; Ramaswamy, Sriram; Shivashankar, G V

2014-01-21

The cell nucleus functions amidst active cytoskeletal filaments, but its response to their contractile stresses is largely unexplored. We study the dynamics of the nuclei of single fibroblasts, with cell migration suppressed by plating onto micro-fabricated patterns. We find the nucleus undergoes noisy but coherent rotational motion. We account for this observation through a hydrodynamic approach, treating the nucleus as a highly viscous inclusion residing in a less viscous fluid of orientable filaments endowed with active stresses. Lowering actin contractility selectively by introducing blebbistatin at low concentrations drastically reduced the speed and coherence of the angular motion of the nucleus. Time-lapse imaging of actin revealed a correlated hydrodynamic flow around the nucleus, with profile and magnitude consistent with the results of our theoretical approach. Coherent intracellular flows and consequent nuclear rotation thus appear to be an intrinsic property of cells.

Multi-quark effects in high energy nucleon-nucleon and nucleus-nucleus collisions

International Nuclear Information System (INIS)

Besliu, C.; Caraciuc, I.; Jipa, A.; Olariu, A.; Topor-Pop, R.; Cotorobai, F.; Pantea, D.; Popa, L.; Popa, V.; Topor-Pop, V.

1988-02-01

Recent data obtained in two experiments performed in the framework of the Bucharest-Dubna collaboration are presented, i.e.: the observation of narrow dibaryonic resonances is neutron-proton interactions in 1mHBC at different momenta of incident neutrons in the range 1-5 GeV/c, and the cumulative production of negative pions in nucleus-nucleus interactions in SKM-200 streamer chamber at 4.5 GeV/c. (authors)

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

Microscopic model of nucleus-nucleus collisions

International Nuclear Information System (INIS)

Harvey, B.G.

1986-04-01

The collision of two nuclei is treated as a collection of collisions between the nucleons of the projectile and those of the target nucleus. The primary projectile fragments contain only those nucleons that did not undergo a collision. The inclusive and coincidence cross sections result from the decay of the excited primary fragments. 15 refs., 5 figs

Sex specific recruitment of a medial prefrontal cortex-hippocampal-thalamic system during context-dependent renewal of responding to food cues in rats.

Science.gov (United States)

Anderson, Lauren C; Petrovich, Gorica D

2017-03-01

Renewal, or reinstatement, of responding to food cues after extinction may explain the inability to resist palatable foods and change maladaptive eating habits. Previously, we found sex differences in context-dependent renewal of extinguished Pavlovian conditioned responding to food cues. Context-induced renewal involves cue-food conditioning and extinction in different contexts and the renewal of conditioned behavior is induced by return to the conditioning context (ABA renewal). Male rats showed renewal of responding while females did not. In the current study we sought to identify recruitment of key neural systems underlying context-mediated renewal and sex differences. We examined Fos induction within the ventromedial prefrontal cortex (vmPFC), hippocampal formation, thalamus and amygdala in male and female rats during the test for renewal. We found sex differences in vmPFC recruitment during renewal. Male rats in the experimental condition showed renewal of responding and had more Fos induction within the infralimbic and prelimbic vmPFC areas compared to controls that remained in the same context throughout training and testing. Females in the experimental condition did not show renewal or an increase in Fos induction. Additionally, Fos expression differed between experimental and control groups and between the sexes in the hippocampal formation, thalamus and amygdala. Within the ventral subiculum, the experimental groups of both sexes had more Fos compared to control groups. Within the dorsal CA1 and the anterior region of the paraventricular nucleus of the thalamus, in males, the experimental group had higher Fos induction, while both females groups had similar number of Fos-positive neurons. Within the capsular part of the central amygdalar nucleus, females in the experimental group had higher Fos induction, while males groups had similar amounts. The differential recruitment corresponded to the behavioral differences between males and females and suggests

K+ nucleus total cross sections

International Nuclear Information System (INIS)

Sawafta, R.

1990-01-01

The scattering of K + mesons from nuclei has attracted considerable interest in the last few years. The K + holds a very special position as the weakest of all strongly interaction probes. The average cross section is not larger than about 10 mb at lab momenta below 800 MeV/c, corresponding to a mean free path in the nucleus larger than 5 fm. Thus the K + is capable of probing the entire volume of the nucleus. Single scattering of the K + with a nucleon in the nucleus dominates the nuclear scattering, and only small and calculable higher order corrections are needed. The nucleon is a dynamical entity and its internal structure can, in principle, be altered by its surrounding nuclear environment. This work reports an experiment in which the K + is used to compare the nucleon in the nucleus with a free nucleon

Thalamic deep brain stimulation for the treatment of tremor due to multiple sclerosis: a prospective study of tremor and quality of life.

Science.gov (United States)

Berk, Caglar; Carr, Jason; Sinden, Marci; Martzke, Jeff; Honey, Christopher R

2002-10-01

In several studies a significant reduction in tremor after thalamic deep brain stimulation (DBS) has been reported among patients with multiple sclerosis (MS). It has not been determined if this results in an improved quality of life. In this study the authors prospectively evaluated the effects of thalamic DBS on tremor and quality of life. Videotapes of the patients' tremor were made preoperatively and 2 and 12 months postoperatively, and tremor was scored by a neurologist blinded to the treatment. Patients were tested pre- and postoperatively to measure any changes in their reported ability to perform selected activities of daily living and in their health-related quality of life. Patients were asked to complete a questionnaire about their satisfaction with the surgery. Postoperative changes were examined using paired t-tests. There were significant reductions in postural, action, and overall tremor at 2 and 12 months postoperatively. The patients' reported ability to feed themselves was significantly improved 2 months after surgery (p = 0.01). There were short-term trends toward improvement in reported dressing ability, personal hygiene, and writing. There were no significant changes in the SF-36 subscales or total score. In this cohort of patients with MS who suffered from tremor, thalamic DBS significantly improved their tremor and ability to feed themselves. Patient satisfaction with the procedure, however, was variable. Preoperative patient education about what functions might (and might not) be improved is crucial to avoid unrealistic expectations. Our results indicate that younger patients with MS tremor who had a shorter disease duration and no superimposed ataxia benefited most from this surgery.

Random matrix theory and analysis of nucleus-nucleus collision at high energies

International Nuclear Information System (INIS)

Shahaliev, E.I.; Inst. of Radiation Problems, Baku; ); Kuznetsov, A.A.; Suleymanov, M.K.; ); Teryaev, O.V.; )

2006-01-01

A novel method for analysis of experimental data obtained at relativistic nucleus-nucleus collisions is proposed. The method, based on the ideas of Random Matrix Theory, is applied to detect systematic errors that occur at measurements of momentum distributions of emitted particles. The unfolded momentum distribution is well described by the Gaussian orthogonal ensemble of random matrices, when the uncertainty in the momentum distribution is maximal. The method is free from unwanted background contributions [ru

Color oscillations of nucleons in a nucleus

International Nuclear Information System (INIS)

Petrov, V.A.; Smirnov, A.Yu.

1987-01-01

Possibility of nucleus description as an object consisting of quarks and gluons is considered. A model of two-nucleon interaction in a nucleus is presented and analytical expressions for the nucleus nucleon ground state wave functions and also for nuclear nucleon structure functions are obtained. The carried out analysis shows that the suggested model permits to express the nucleus structure functions at quark level only by means of nucleon and Δ-isobaric degrees of freedom

Getting signals into the brain: visual prosthetics through thalamic microstimulation.

Science.gov (United States)

Pezaris, John S; Eskandar, Emad N

2009-07-01

Common causes of blindness are diseases that affect the ocular structures, such as glaucoma, retinitis pigmentosa, and macular degeneration, rendering the eyes no longer sensitive to light. The visual pathway, however, as a predominantly central structure, is largely spared in these cases. It is thus widely thought that a device-based prosthetic approach to restoration of visual function will be effective and will enjoy similar success as cochlear implants have for restoration of auditory function. In this article the authors review the potential locations for stimulation electrode placement for visual prostheses, assessing the anatomical and functional advantages and disadvantages of each. Of particular interest to the neurosurgical community is placement of deep brain stimulating electrodes in thalamic structures that has shown substantial promise in an animal model. The theory of operation of visual prostheses is discussed, along with a review of the current state of knowledge. Finally, the visual prosthesis is proposed as a model for a general high-fidelity machine-brain interface.

Percolation Model of Nuclear Multifragmentation in High Energy Nucleus-Nucleus Interactions

International Nuclear Information System (INIS)

Abdel-Waged, Kh.

1994-01-01

A hybrid model based on Reggeon theory inspired model of nuclear distribution, which was successful in explaining the cascading of particles in high energy nucleus-nucleus interactions, and percolation model is proposed. In the framework of this model the yield of the fragment in p + Ag, Au at 350 GeV and C + Ag, Au at 3.6 GeV/nucleon as well as the charge distribution of fragments in Kr, Xe and U interactions with emulsion at ∼ 1 GeV/nucleon is correctly described. 32 refs., 3 figs

[Thalamus and Attention].

Science.gov (United States)

Tokoro, Kazuhiko; Sato, Hironobu; Yamamoto, Mayumi; Nagai, Yoshiko

2015-12-01

Attention is the process by which information and selection occurs, the thalamus plays an important role in the selective attention of visual and auditory information. Selective attention is a conscious effort; however, it occurs subconsciously, as well. The lateral geniculate body (LGB) filters visual information before it reaches the cortex (bottom-up attention). The thalamic reticular nucleus (TRN) provides a strong inhibitory input to both the LGB and pulvinar. This regulation involves focusing a spotlight on important information, as well as inhibiting unnecessary background information. Behavioral contexts more strongly modulate activity of the TRN and pulvinar influencing feedforward and feedback information transmission between the frontal, temporal, parietal and occipital cortical areas (top-down attention). The medial geniculate body (MGB) filters auditory information the TRN inhibits the MGB. Attentional modulation occurring in the auditory pathway among the cochlea, cochlear nucleus, superior olivary complex, and inferior colliculus is more important than that of the MGB and TRN. We also discuss the attentional consequence of thalamic hemorrhage.

Energy loss, range and fluence distributions, total reaction and projectile fragment production cross sections for proton-nucleus and nucleus-nucleus interactions

International Nuclear Information System (INIS)

Sihver, L.; Kanai, T.

1992-07-01

We have developed a computer code for calculations of energy loss (dE/dx) and range distributions for heavy ions in any media. The results from our calculations are in very good agreement with previous calculations. We have developed semiempirical total reaction cross section formulae for proton-nucleus (with Z p ≤26) and nucleus-nucleus (with Z p and Z t ≤26) reactions. These formulae apply for incident energies above 15 MeV and 100 MeV/nucleon respectively. From the total reaction cross sections, we can calculate the mean free paths and the fluence distributions of protons and heavy ions in any media. We have compared all the calculated reaction cross sections and the mean free paths with experimental data, and the agreement is good. We have also constructed a procedure for calculating projectile fragment production cross sections, by scaling semiempirical proton-nucleus partial cross section systematics. The scaling is performed using a scaling parameter deduced from our reaction cross sections formulae, and additional enhancements factors. All products with atomic number ranging from that of the projectile (Z p ) down to Z=2 can be calculated. The agreement between the calculated cross sections and the experimental data is better than earlier published results. (author)

Management bedding : vrijloopstal met composterende bedding van houtsnippers

NARCIS (Netherlands)

Boer, de H.C.; Wiersma, M.; Galama, P.J.; Szanto, G.L.

2015-01-01

In de vrijloopstal liggen de koeien meestal op een organische bedding en scheiden daar mest (feces en urine) uit. Om de bedding voldoende droog en schoon te houden wordt er regelmatig nieuw strooisel aangevoerd en wordt de toplaag bewerkt. Op basis van onderzoek- en praktijkervaringen tot nu toe

Evidence for thalamic involvement in the thermal grill illusion: an FMRI study.

Directory of Open Access Journals (Sweden)

Fredrik Lindstedt

Full Text Available BACKGROUND: Perceptual illusions play an important role in untangling neural mechanisms underlying conscious phenomena. The thermal grill illusion (TGI has been suggested as a promising model for exploring percepts involved in neuropathic pain, such as cold-allodynia (pain arising from contact with innocuous cold. The TGI is an unpleasant/painful sensation from touching juxtapositioned bars of cold and warm innocuous temperatures. AIM: To develop an MRI-compatible TGI-unit and explore the supraspinal correlates of the illusion, using fMRI, in a group of healthy volunteers. METHODS: We constructed a TGI-thermode allowing the rapid presentation of warm(41°C, cold(18°C and interleaved(41°C+18°C = TGI temperatures in an fMRI-environment. Twenty volunteers were tested. The affective-motivational ("unpleasantness" and sensory-disciminatory ("pain-intensity" dimensions of each respective stimulus were rated. Functional images were analyzed at a corrected α-level <0.05. RESULTS: The TGI was rated as significantly more unpleasant and painful than stimulation with each of its constituent temperatures. Also, the TGI was rated as significantly more unpleasant than painful. Thermal stimulation versus neutral baseline revealed bilateral activations of the anterior insulae and fronto-parietal regions. Unlike its constituent temperatures the TGI displayed a strong activation of the right (contralateral thalamus. Exploratory contrasts at a slightly more liberal threshold-level also revealed a TGI-activation of the right mid/anterior insula, correlating with ratings of unpleasantness (rho = 0.31. CONCLUSION/SIGNIFICANCE: To the best of our knowledge, this is the first fMRI-study of the TGI. The activation of the anterior insula is consistent with this region's putative role in processing of homeostatically relevant feeling-states. Our results constitute the first neurophysiologic evidence of thalamic involvement in the TGI. Similar thalamic activity

Transverse Energy in nucleus-nucleus collisions: A review

International Nuclear Information System (INIS)

Tincknell, M.

1988-01-01

The status of Transverse Energy (E/sub T/) in relativistic nucleus-nucleus collisions at the Brookhaven AGS and the CERN SPS is reviewed. The definition of E/sub T/ and its physical significance are discussed. The basic techniques and limitations of the experimental measurements are presented. The acceptances of the major experiments to be discussed are shown, along with remarks about their idiosyncrasies. The data demonstrate that the nuclear geometry of colliding spheres primarily determines the shapes of the observed spectra. Careful account of the acceptances is crucial to comparing and interpreting results. It is concluded that nuclear stopping power is high, and that the amount of energy deposited into the interaction volume is increasing with beam energy even at SPS energies. The energy densities believed to be obtained at the SPS are close to the critical values predicted for the onset of a quark-gluon plasma. 25 refs., 8 figs

Effect of bed particles to combustion of gases in fluidized bed

Energy Technology Data Exchange (ETDEWEB)

Raiko, R.; Wallen, V.; Etelaeaho, R.; Correia, S. [Tampere Univ. of Technology (Finland). Energy and Process Engineering

1997-10-01

The objective of this project was to obtain experimental data on effects of sand particles to the combustion of gases. The effect of the surface area of the particles was tested using different sized particles. The fluidized bed reactor used in these experiments was a stainless-steel tube with an internal diameter of 42 mm surrounded by an electric heater. The test rig was built in the Laboratory of Energy and Process Engineering at Tampere University of Technology. In order to elucidate the possible changes of particle surface, microscopic and porosimetric studies were conducted with both fresh bed particles and used bed particles. These measurements indicate that carbon monoxide significantly reacts with oxygen in the particulate or emulsion phase of a fluidized bed, if the residence time is long enough. The reaction rate depends mainly on temperature, air coefficient, residence time and particle size of the solids. It seems that the combustion enhances if the average particle size increases. Whether this is caused by increased free path length or reduced specific surface area of the bed is yet unknown. The first might be more probable cause because the majority of reactions often took place in the freeboard right above the bed. It was clear that the bed hindered proper combustion in several cases. (orig.)

Thalamic metabolic abnormalities in patients with Huntington's disease measured by magnetic resonance spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Casseb, R.F.; Castellano, G., E-mail: gabriela@ifi.unicamp.br [Cooperacao Interinstitucional de Apoio a Pesquisas sobre o Cerebro (Programa CInAPCe), Sao Paulo, SP (Brazil); Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Instituto de Fisica Gleb Wataghin. Dept. de Raios Cosmicos e Cronologia; D' Abreu, A.; Cendes, F. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Dept. de Neurologia. Lab. de Neuroimagem; Cooperacao Interinstitucional de Apoio a Pesquisas sobre o Cerebro (Programa CInAPCe), Sao Paulo, SP (Brazil); Ruocco, H.H. [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. de Ciencias Medicas. Dept. de Neurologia. Lab. de Neuroimagem; Lopes-Cendes, I., E-mail: seixas.fk@gmail.com [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. de Ciencias Medicas. Dept. de Genetica Medica; Cooperacao Interinstitucional de Apoio a Pesquisas sobre o Cerebro (Programa CInAPCe), Sao Paulo, SP (Brazil)

2013-08-15

Huntington's disease (HD) is a neurologic disorder that is not completely understood; its fundamental physiological mechanisms and chemical effects remain somewhat unclear. Among these uncertainties, we can highlight information about the concentrations of brain metabolites, which have been widely discussed. Concentration differences in affected, compared to healthy, individuals could lead to the development of useful tools for evaluating the progression of disease, or to the advance of investigations of different/alternative treatments. The aim of this study was to compare the thalamic concentration of metabolites in HD patients and healthy individuals using magnetic resonance spectroscopy. We used a 2.0-Tesla magnetic field, repetition time of 1500 ms, and echo time of 135 ms. Spectra from 40 adult HD patients and 26 control subjects were compared. Quantitative analysis was performed using the LCModel method. There were statistically significant differences between HD patients and controls in the concentrations of N-acetylaspartate+N-acetylaspartylglutamate (NAA+NAAG; t-test, P,0.001), and glycerophosphocholine+phosphocholine (GPC+PCh; t-test, P=0.001) relative to creatine+phosphocreatine (Cr+PCr). The NAA+NAAG/Cr+PCr ratio was decreased by 9% and GPC+PCh/Cr+PCr increased by 17% in patients compared with controls. There were no correlations between the concentration ratios and clinical features. Although these results could be caused by T1 and T2 changes, rather than variations in metabolite concentrations given the short repetition time and long echo time values used, our findings point to thalamic dysfunction, corroborating prior evidence. (author)

Bed retained products in swept fixed bed (SFB) coal hydropyrolysis

Energy Technology Data Exchange (ETDEWEB)

Mastral, A.M.; Perez-Surio, M.J. [CSIC, Zaragosa (Spain). Inst. de Carboquimica

1997-12-31

The hydropyrolysis of a low rank coal in a swept fixed bed (SFB) reactor is carried out by fixing the hydrogen pressure (40 kg/cm{sup 2}), the hydrogen flow (2 l/min) and the residence time (10 min) at increasing temperatures (400 C, 500 C and 600 C) and coal bed heights (h, 1.5h, 2h, 2.5h and 3h). It is shown that the percentages of tars and char directly depend on the coal bed height and that there is not only a quantitative dependence, but also the height of the coal bed is very important and plays a relevant role on the nature of the conversion products. (orig.)

Visual plasticity : Blindsight bridges anatomy and function in the visual system

NARCIS (Netherlands)

Tamietto, M.; Morrone, M.C.

2016-01-01

Some people who are blind due to damage to their primary visual cortex, V1, can discriminate stimuli presented within their blind visual field. This residual function has been recently linked to a pathway that bypasses V1, and connects the thalamic lateral geniculate nucleus directly with the

In-bed accountability of tritium in production scale metal hydride storage beds

International Nuclear Information System (INIS)

Klein, J.E.

1995-01-01

An ''in-bed accountability'' (IBA) flowing gas calorimetric measurement method has been developed and implemented to eliminate the need to remove tritium from production scale metal hydride storage beds for inventory measurement purposes. Six-point tritium IBA calibration curves have been completed for two, 390 gram tritium metal hydride storage beds. The calibration curves for the two tritium beds are similar to those obtained from the ''cold'' test program. Tritium inventory errors at the 95 percent confidence level ranged from ± 7.3 to 8.6 grams for the cold test results compared to ± 4.2 to 7.5 grams obtained for the two tritium calibrated beds

Thalamocortical Projection Neuron and Interneuron Numbers in the Visual Thalamic Nuclei of the Adult C57BL/6 Mouse.

Science.gov (United States)

Evangelio, Marian; García-Amado, María; Clascá, Francisco

2018-01-01

A key parameter to constrain predictive, bottom-up circuit models of a given brain domain is the number and position of the neuronal populations involved. These include not only the neurons whose bodies reside within the domain, but also the neurons in distant regions that innervate the domain. The mouse visual cortex receives its main subcortical input from the dorsal lateral geniculate nucleus (dLGN) and the lateral posterior (LP) complex of the thalamus. The latter consists of three different nuclei: lateral posterior lateral (LPL), lateral posterior medial rostral (LPMR), and lateral posterior medial caudal (LPMC), each exhibiting specific patterns of connections with the various visual cortical areas. Here, we have determined the number of thalamocortical projection neurons and interneurons in the LP complex and dLGN of the adult C57BL/6 male mouse. We combined Nissl staining and histochemical and immunolabeling methods for consistently delineating nuclei borders, and applied unbiased stereological cell counting methods. Thalamic interneurons were identified using GABA immunolabeling. The C57BL/6 dLGN contains ∼21,200 neurons, while LP complex contains ∼31,000 total neurons. The dLGN and LP are the only nuclei of the mouse dorsal thalamus containing substantial numbers GABA-immunoreactive interneurons. These interneurons, however, are scarcer than previously estimated; they are 5.6% of dLGN neurons and just 1.9% of the LP neurons. It can be thus inferred that the dLGN contains ∼20,000 and the LP complex ∼30,400 thalamocortical projection neurons (∼12,000 in LPL, 15,200 in LPMR, and 4,200 in LPMC). The present dataset is relevant for constraining models of mouse visual thalamocortical circuits, as well as for quantitative comparisons between genetically modified mouse strains, or across species.

[Thalamic Stroke and Associated Behavior Disorders. Possibilities for Integral Management: Case Report].

Science.gov (United States)

Camargo, Loida Camargo; Sánchez, Katherine Parra

2012-06-01

Since ancient Greece, cerebrovascular accidents have been described with no variation. Even today, they are still a catastrophic event in the lives of patients with a high risk of disabling sequelae. Case report of a 56-year male patient with thalamic ischemia. The intervention with integral strategies involving pharmacological management and cognitive interventions was decisive for the satisfactory evolution of the patient. The management of patients with cerebrovascular accidents cannot be limited to the emergency room. Pharmacological advances in programs and cognitive intervention methods provide intervention tools from the very beginning of the stroke thus reducing the impact of long-term sequelae, and consequently enabling a better reintegration of the patient to his family. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

Aspects of Coulomb dissociation and interference in peripheral nucleus-nucleus collisions

International Nuclear Information System (INIS)

Nystrand, Joakim; Baltz, Anthony; Klein, Spencer R.

2001-01-01

Coherent vector meson production in peripheral nucleus-nucleus collisions is discussed. These interactions may occur for impact parameters much larger than the sum of the nuclear radii. Since the vector meson production is always localized to one of the nuclei, the system acts as a two-source interferometer in the transverse plane. By tagging the outgoing nuclei for Coulomb dissociation it is possible to obtain a measure of the impact parameter and thus the source separation in the interferometer. This is of particular interest since the life-time of the vector mesons are generally much shorter than the impact parameters of the collisions

Neutrino-nucleus collision at intermediate energy

International Nuclear Information System (INIS)

Kosmas, T.S.; Oset, E.

1999-01-01

Neutrino-nucleus reactions at low and intermediate energy up to E ν = 500 MeV are studied for the most interesting nuclei from an experimental point of view. We focus on neutrino-nucleus cross-sections of semi-inclusive processes, for which recent measurements from radiochemical experiments at LAMPF and KARMEN laboratories are available. The method employed uses the modified Lindhard function for the description of the particle-hole excitations of the final nucleus via a local density approximation. (authors)

Thermal Analysis of Fluidized Bed and Fixed Bed Latent Heat Thermal Storage System

Science.gov (United States)

Beemkumar, N.; Karthikeyan, A.; Shiva Keshava Reddy, Kota; Rajesh, Kona; Anderson, A.

2017-05-01

Thermal energy storage technology is essential because its stores available energy at low cost. Objective of the work is to store the thermal energy in a most efficient method. This work is deal with thermal analysis of fluidized bed and fixed bed latent heat thermal storage (LHTS) system with different encapsulation materials (aluminium, brass and copper). D-Mannitol has been used as phase change material (PCM). Encapsulation material which is in orbicular shape with 4 inch diameter and 2 mm thickness orbicular shaped product is used. Therminol-66 is used as a heat transfer fluid (HTF). Arrangement of encapsulation material is done in two ways namely fluidized bed and fixed bed thermal storage system. Comparison was made between the performance of fixed bed and fluidized bed with different encapsulation material. It is observed that from the economical point of view aluminium in fluidized bed LHTS System has highest efficiency than copper and brass. The thermal energy storage system can be analyzed with fixed bed by varying mass flow rate of oil paves a way to find effective heat energy transfer.

Transverse and radial flow in intermediate energy nucleus-nucleus collisions

International Nuclear Information System (INIS)

Vestfall, D. Gary

1997-01-01

We have studied transverse and radial flow in nucleus-nucleus collisions ranging in energy from 15 to 155 MeV/nucleon. We have measured the impact parameter dependence of the balance energy for Ar + Sc and compared the results with Quantum Molecular Dynamics calculations with and without momentum dependence. We have shown that transverse flow and the balance energy dependence on the isospin of the system using the systems 58 Fe + 58 Fe, 58 Ni + 58 Ni, and 58 Mn + 58 Fe. These results are compared with Boltzmann-Uehling-Uehlenbeck calculations incorporating isospin-dependence. We have measured radial flow for Ar + Sc and find that about 50% of the observed energy is related to radial flow. (author)

Nuclear energy release in hadron-nucleus collisions

International Nuclear Information System (INIS)

Strugalski, Z.; Strugalska-Gola, E.

1998-01-01

Energy release process in nuclear reactions induced by fast hadrons in hadron-nucleus collisions is discussed. Some portion of the internal nuclear energy is released when the locally damaged in a collision, and instable therefore, residual target nucleus transits itself into light nuclear fragments (nucleons, D, T) and a stable lighter final nucleus or some number of stable lighter nuclei. It is not excluded that in some of the collisions the induced intranuclear nuclear reactions may be energy overcompensating. Corresponding reconnaissance should be made - in analysing the nuclear reactions induced in hadron-nucleus collisions

Thermal Bremsstrahlung probing nuclear multifragmentation in nucleus-nucleus collisions around the Fermi energy

International Nuclear Information System (INIS)

D'Enterria, D.G.

2000-05-01

The thermodynamical properties of nuclear matter at moderate temperatures and densities, in the vicinity of the predicted nuclear liquid-gas phase transition, are studied using as experimental probe the hard-photons (E γ > 30 MeV) emitted in nucleus-nucleus collisions. Photon and charged-particle production in four different heavy-ion reactions (Ar 36 + Au 197 , Ag 107 , Ni 58 , C 12 at 60 A*MeV) is measured exclusively and inclusively coupling the TAPS photon spectrometer with two charged-particle and intermediate-mass-fragment detectors covering nearly 4π. We confirm that Bremsstrahlung emission in first-chance (off-equilibrium) proton-neutron collisions (pnγ) is the dominant origin of hard photons. We also firmly establish the existence of a thermal radiation component emitted in second-chance proton-neutron collisions. This thermal Bremsstrahlung emission takes place in semi-central and central nucleus-nucleus reactions involving heavy targets. We exploit this observation i) to demonstrate that thermal equilibrium is reached during the reaction, ii) to establish a new thermometer of nuclear matter based on Bremsstrahlung photons, iii) to derive the thermodynamical properties of the excited nuclear sources and, in particular, to establish a 'caloric curve' (temperature versus excitation energy), and iv) to assess the time-scales of the nuclear break-up process. (author)

Bed care for patients in palliative settings: considering risks to caregivers and bed surfaces.

Science.gov (United States)

Fragala, Guy

2015-02-01

Ensuring patients are comfortable in bed is key to effective palliative care, but when moving and positioning patients in bed, health professionals face an occupational risk of injury. The turning and positioning (TAP) system is a new method of moving patients in bed, that evidence has shown to reduce the risk of injury to caregivers. Providing the correct bed surface is another aspect of bed care essential to the comfort of the palliative patient, and to aid wound prevention and treatment. It is important to take a patient-centred approach when considering the most appropriate bed surface patients. This article provides an overview and discussion of these two aspects of bed care for palliative patients.

Fluid bed porosity equation for an inverse fluidized bed bioreactor with particles growing biofilm

International Nuclear Information System (INIS)

Campos-Diaz, K. E.; Limas-Ballesteros, R.

2009-01-01

Fluid Bed Bioreactor performance is strongly affected by bed void fraction or bed porosity fluctuations. Particle size enlargement due to biofilm growth is an important factor that is involved in these variations and until now there are no mathematical equations that consider biofilm growth. In this work a mathematical equation is proposed to calculate bed void fraction in an inverse fluid bed bioreactor. (Author)

Nucleon molecular orbitals and the transition mechanism between molecular orbitals in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Imanishi, B.; Misono, S.; von Oertzen, W.; Voit, H.

1988-08-01

The molecular orbitals of the nucleon(s) in nucleus-nucleus collisions are dynamically defined as a linear combination of nucleon single-particle orbits (LCNO) in a rotating frame by using the coupled-reaction-channel (CRC) theory. Nucleon molecular orbitals and the promotions of nucleon, - especially due to the Landau-Zener radial coupling are discussed with the method above mentioned. (author)

A food-predictive cue attributed with incentive salience engages subcortical afferents and efferents of the paraventricular nucleus of the thalamus.

Science.gov (United States)

Haight, Joshua L; Fuller, Zachary L; Fraser, Kurt M; Flagel, Shelly B

2017-01-06

The paraventricular nucleus of the thalamus (PVT) has been implicated in behavioral responses to reward-associated cues. However, the precise role of the PVT in these behaviors has been difficult to ascertain since Pavlovian-conditioned cues can act as both predictive and incentive stimuli. The "sign-tracker/goal-tracker" rat model has allowed us to further elucidate the role of the PVT in cue-motivated behaviors, identifying this structure as a critical component of the neural circuitry underlying individual variation in the propensity to attribute incentive salience to reward cues. The current study assessed differences in the engagement of specific PVT afferents and efferents in response to presentation of a food-cue that had been attributed with only predictive value or with both predictive and incentive value. The retrograde tracer fluorogold (FG) was injected into the PVT or the nucleus accumbens (NAc) of rats, and cue-induced c-Fos in FG-labeled cells was quantified. Presentation of a predictive stimulus that had been attributed with incentive value elicited c-Fos in PVT afferents from the lateral hypothalamus, medial amygdala (MeA), and the prelimbic cortex (PrL), as well as posterior PVT efferents to the NAc. PVT afferents from the PrL also showed elevated c-Fos levels following presentation of a predictive stimulus alone. Thus, presentation of an incentive stimulus results in engagement of subcortical brain regions; supporting a role for the hypothalamic-thalamic-striatal axis, as well as the MeA, in mediating responses to incentive stimuli; whereas activity in the PrL to PVT pathway appears to play a role in processing the predictive qualities of reward-paired stimuli. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

Individual mediodorsal thalamic neurons project to multiple areas of the rat prefrontal cortex: A single neuron-tracing study using virus vectors.

Science.gov (United States)

Kuramoto, Eriko; Pan, Shixiu; Furuta, Takahiro; Tanaka, Yasuhiro R; Iwai, Haruki; Yamanaka, Atsushi; Ohno, Sachi; Kaneko, Takeshi; Goto, Tetsuya; Hioki, Hiroyuki

2017-01-01

The prefrontal cortex has an important role in a variety of cognitive and executive processes, and is generally defined by its reciprocal connections with the mediodorsal thalamic nucleus (MD). The rat MD is mainly subdivided into three segments, the medial (MDm), central (MDc), and lateral (MDl) divisions, on the basis of the cytoarchitecture and chemoarchitecture. The MD segments are known to topographically project to multiple prefrontal areas at the population level: the MDm mainly to the prelimbic, infralimbic, and agranular insular areas; the MDc to the orbital and agranular insular areas; and the MDl to the prelimbic and anterior cingulate areas. However, it is unknown whether individual MD neurons project to single or multiple prefrontal cortical areas. In the present study, we visualized individual MD neurons with Sindbis virus vectors, and reconstructed whole structures of MD neurons. While the main cortical projection targets of MDm, MDc, and MDl neurons were generally consistent with those of previous results, it was found that individual MD neurons sent their axon fibers to multiple prefrontal areas, and displayed various projection patterns in the target areas. Furthermore, the axons of single MD neurons were not homogeneously spread, but were rather distributed to form patchy axon arbors approximately 1 mm in diameter. The multiple-area projections and patchy axon arbors of single MD neurons might be able to coactivate cortical neuron groups in distant prefrontal areas simultaneously. Furthermore, considerable heterogeneity of the projection patterns is likely, to recruit the different sets of cortical neurons, and thus contributes to a variety of prefrontal functions. J. Comp. Neurol. 525:166-185, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Transverse-momentum distribution of produced particles in ultrarelativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Ban-Hao, S.; Wong, C.

1985-01-01

In order to discern coherent or collective processes from incoherent processes in nucleus-nucleus reactions at high energies, we study the transverse-momentum distribution of the produced particles with an incoherent-multiple-collision model. In this model, the projectile nucleon makes successive inelastic collisions with nucleons in the target nucleus, the probability of such collisions being given by the thickness function and the nucleon-nucleon inelastic cross section. It is assumed that each baryon-baryon collision produces particles and degrades momenta just as a baryon-baryon collision in free space, and that there are no secondary collisions between the produced particles and the nucleons. We found that the average transverse momentum and the charged-multiplicity data at Fermilab and CERN ISR energies can be well explained by such a model. However, the average transverse momentum for some events observed by the Japanese-American cooperative emulsion experiment (JACEE) associated with large energy density in the central rapidity region differ markedly from the model results. Such a deviation indicates the presence of coherent or collective effects for these collisions and may indicate the possibility of a formation of quark-gluon plasma

High energy nuclear database: a test-bed for nuclear data information technology

International Nuclear Information System (INIS)

Brown, D.A.; Vogt, R.; Beck, B.; Pruet, J.; Vogt, R.

2008-01-01

We describe the development of an on-line high-energy heavy-ion experimental database. When completed, the database will be searchable and cross-indexed with relevant publications, including published detector descriptions. While this effort is relatively new, it will eventually contain all published data from older heavy-ion programs as well as published data from current and future facilities. These data include all measured observables in proton-proton, proton-nucleus and nucleus-nucleus collisions. Once in general use, this database will have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models for a broad range of experiments. Furthermore, there is a growing need for compilations of high-energy nuclear data for applications including stockpile stewardship, technology development for inertial confinement fusion, target and source development for upcoming facilities such as the International Linear Collider and homeland security. This database is part of a larger proposal that includes the production of periodic data evaluations and topical reviews. These reviews would provide an alternative and impartial mechanism to resolve discrepancies between published data from rival experiments and between theory and experiment. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support. This project serves as a test-bed for the further development of an object-oriented nuclear data format and database system. By using 'off-the-shelf' software tools and techniques, the system is simple, robust, and extensible. Eventually we envision a 'Grand Unified Nuclear Format' encapsulating data types used in the ENSDF, Endf/B, EXFOR, NSR and other formats, including processed data formats. (authors)

Fast detector for triggering on charged particle multiplicity for relativistic nucleus-nucleus collisions

International Nuclear Information System (INIS)

Agakishiev, G.; Man'yakov, P.K.; Drees, A.

1997-01-01

The simple and fast detector of charged particle multiplicity for relativistic nucleus-nucleus collision studies is performed. The multiplicity detector has been designed for the first level trigger of the CERES/NA45 experiment to study Pb-Au collisions at CERN SPS energies. The detector has allowed a realization of the 40 ns trigger for selection of events with definite impact parameter. The construction, operation characteristics, method of calibration, and testing results are described in detail

Pebble-bed reactor

International Nuclear Information System (INIS)

Lohnert, G.; Mueller-Frank, U.; Heil, J.

1976-01-01

A pebble-bed nuclear reactor of large power rating comprises a container having a funnel-shaped bottom forming a pebble run-out having a centrally positioned outlet. A bed of downwardly-flowing substantially spherical nuclear fuel pebbles is positioned in the container and forms a reactive nuclear core maintained by feeding unused pebbles to the bed's top surface while used or burned-out pebbles run out and discharge through the outlet. A substantially conical body with its apex pointing upwardly and its periphery spaced from the periphery of the container spreads the bottom of the bed outwardly to provide an annular flow down the funnel-shaped bottom forming the runout, to the discharge outlet. This provides a largely constant downward velocity of the spheres throughout the diameter of the bed throughout a substantial portion of the down travel, so that all spheres reach about the same burned-out condition when they leave the core, after a single pass through the core area

The Safety of Hospital Beds

Science.gov (United States)

Gervais, Pierre; Pooler, Charlotte; Merryweather, Andrew; Doig, Alexa K.; Bloswick, Donald

2015-01-01

To explore the safety of the standard and the low hospital bed, we report on a microanalysis of 15 patients’ ability to ingress, move about the bed, and egress. The 15 participants were purposefully selected with various disabilities. Bed conditions were randomized with side rails up or down and one low bed with side rails down. We explored the patients’ use of the side rails, bed height, ability to lift their legs onto the mattress, and ability to turn, egress, and walk back to the chair. The standard bed was too high for some participants, both for ingress and egress. Side rails were used by most participants when entering, turning in bed, and exiting. We recommend that side rails be reconsidered as a means to facilitate in-bed movement, ingress, and egress. Furthermore, single deck height settings for all patients are not optimal. Low beds as a safety measure must be re-evaluated. PMID:28462302

Fluid-bed combustion

Energy Technology Data Exchange (ETDEWEB)

Hunt, G.; Schoebotham, N.

1981-02-01

In Energy Equipment Company's two-stage fluidized bed system, partial combustion in a fluidized bed is followed by burn-off of the generated gases above the bed. The system can be retrofitted to existing boilers, and can burn small, high ash coal efficiently. It has advantages when used as a hot gas generator for process drying. Tests on a boiler at a Cadbury Schweppes plant are reported.

Electromagnetic processes in nucleus-nucleus collisions relating to space radiation research

Science.gov (United States)

Norbury, John W.

1992-01-01

Most of the papers within this report deal with electromagnetic processes in nucleus-nucleus collisions which are of concern in the space radiation program. In particular, the removal of one and two nucleons via both electromagnetic and strong interaction processes has been extensively investigated. The theory of relativistic Coulomb fission has also been developed. Several papers on quark models also appear. Finally, note that the theoretical methods developed in this work have been directly applied to the task of radiation protection of astronauts. This has been done by parameterizing the theoretical formalism in such a fashion that it can be used in cosmic ray transport codes.

Reduced thalamic and pontine connectivity in Kleine-Levin syndrome

Directory of Open Access Journals (Sweden)

Maria eEngström

2014-04-01

Full Text Available The Kleine-Levin syndrome is a rare sleep disorder, characterized by exceptionally long sleep episodes. The neuropathology of the syndrome is unknown and treatment is often inadequate. The aim of the study was to improve understanding of the underlying neuropathology, related to cerebral networks, in Kleine-Levin syndrome during sleep episodes. One patient with Kleine-Levin syndrome and congenital nystagmus, was investigated by resting state functional Magnetic Resonance Imaging during both asymptomatic and hypersomnic periods. Fourteen healthy subjects were also investigated as control samples. Functional connectivity was assessed from seed regions of interest in the thalamus and the dorsal pons. Thalamic connectivity was normal in the asymptomatic patient whereas the connectivity between the brain stem, including dorsal pons, and the thalamus was diminished during hypersomnia. These results suggest that the patient’s nystagmus and hypersomnia might have their pathological origin in adjacent dorsal pontine regions. This finding provides additional knowledge of the cerebral networks involved in the neuropathology of this disabling disorder. Furthermore, these findings regarding a rare syndrome have broad implications and results could be of interest to researchers and clinicians in the whole field of sleep medicine.

Cerebral blood flow in patients with thalamic hemorrhage, 2

International Nuclear Information System (INIS)

Ueda, Mikiya; Matsumoto, Yukihiro; Omiya, Nobuyuki; Mikami, Junichi; Sato, Hiroyuki; Inoue, Yoshitoshi; Okawara, Shuji; Matsuoka, Takahiro; Takeda, Satoshi.

1989-01-01

In twenty-nine patients with thalamic hemorrhage, single photon emission CT (SPECT) and CT were performed in the acute stage. Measurement of cerebral blood flow (CBF) was performed by the 133-Xe inhalation method using SPECT (Tomomatic 64). CT findings such as hematoma volume, involvement of internal capsule, ventricular hematoma and topographical localization of hematoma were investigated. We studied etiological analysis of decreased CBF in the acute stage. CBF values in the group of large-volume hematoma (≥10 ml) decreased moderately on the hematoma side and mildly on the nonhematoma side. CBF values in the group of small-volume hematoma (<10 ml) decreased mildly on the hematoma side but didn't decrease on the nonhematoma side. CBF values of the former on the hematoma side decreased significantly compared with the latter. Linear correlation between hematoma volume and CBF was significant. As to topographical localization, CBF values of the group which involved medial thalamus decreased significantly compared with the other group. Factors of involvement of internal capsule and ventricular hematoma didn't affect CBF values. In conclusion, major factors which affected decreased CBF in the acute stage were hematoma volume and tomographical localization. (author)

An autopsied case of MM1 + MM2-cortical with thalamic-type sporadic Creutzfeldt-Jakob disease presenting with hyperintensities on diffusion-weighted MRI before clinical onset.

Science.gov (United States)

Iwasaki, Yasushi; Mori, Keiko; Ito, Masumi; Mimuro, Maya; Kitamoto, Tetsuyuki; Yoshida, Mari

2017-02-01

A 78-year-old Japanese man presented with rapidly progressive dementia and gait disturbances. Eight months before the onset of clinical symptoms, diffusion-weighted magnetic resonance imaging (DWI) demonstrated hyperintensities in the right temporal, right parietal and left medial occipital cortices. Two weeks after symptom onset, DWI showed extensive hyperintensity in the bilateral cerebral cortex, with regions of higher brightness that existed prior to symptom onset still present. Four weeks after clinical onset, periodic sharp wave complexes were identified on an electroencephalogram. Myoclonus was observed 8 weeks after clinical onset. The patient reached an akinetic mutism state and died 5 months after onset. Neuropathological examination showed widespread cerebral neocortical involvement of fine vacuole-type spongiform changes with large confluent vacuole-type spongiform changes. Spongiform degeneration with neuron loss and hypertrophic astrocytosis was also observed in the striatum and medial thalamus. The inferior olivary nucleus showed severe neuron loss with hypertrophic astrocytosis. Prion protein (PrP) immunostaining showed widespread synaptic-type PrP deposition with perivacuolar-type PrP deposition in the cerebral neocortex. Mild to moderate PrP deposition was also observed extensively in the basal ganglia, thalamus, cerebellum and brainstem, but it was not apparent in the inferior olivary nucleus. PrP gene analysis showed no mutations, and polymorphic codon 129 showed methionine homozygosity. Western blot analysis of protease-resistant PrP showed both type 1 scrapie type PrP (PrP Sc ) and type 2 PrP Sc . Based on the relationship between the neuroimaging and pathological findings, we speculated that cerebral cortical lesions with large confluent vacuoles and type 2 PrP Sc would show higher brightness and continuous hyperintensity on DWI than those with fine vacuoles and type 1 PrP Sc . We believe the present patient had a combined form of MM1�

Pathways for Emotions: Specializations in the Amygdalar, Mediodorsal Thalamic, and Posterior Orbitofrontal Network.

Science.gov (United States)

Timbie, Clare; Barbas, Helen

2015-08-26

The primate amygdala projects to posterior orbitofrontal cortex (pOFC) directly and possibly indirectly through a pathway to the magnocellular mediodorsal thalamic nucleus (MDmc), which may convey signals about the significance of stimuli. However, because MDmc receives input from structures in addition to the amygdala and MDmc projects to areas in addition to pOFC, it is unknown whether amygdalar pathways in MDmc innervate pOFC-bound neurons. We addressed this issue using double- or triple-labeling approaches to identify pathways and key cellular and molecular features in rhesus monkeys. We found that amygdalar terminations innervated labeled neurons in MDmc that project to pOFC. Projection neurons in MDmc directed to pOFC included comparatively fewer "core" parvalbumin neurons that project focally to the middle cortical layers and more "matrix" calbindin neurons that project expansively to the upper cortical layers. In addition, a small and hitherto unknown pathway originated from MDmc calretinin neurons and projected to pOFC. Further, whereas projection neurons directed to MDmc and to pOFC were intermingled in the amygdala, none projected to both structures. Larger amygdalar neurons projected to MDmc and expressed the vesicular glutamate transporter 2 (VGLUT2), which is found in highly efficient "driver" pathways. In contrast, smaller amygdalar neurons directed to pOFC expressed VGLUT1 found in modulatory pathways. The indirect pathway from the amygdala to pOFC via MDmc may provide information about the emotional significance of events and, along with a parallel direct pathway, ensures transfer of signals to all layers of pOFC. The amygdala-the brain's center for emotions-is strongly linked with the orbital cortex, a region associated with social interactions. This study provides evidence that a robust pathway from the amygdala reaches neurons in the thalamus that link directly with the orbital cortex, forming a tight tripartite network. The dual pathways from

Apparatus for controlling fluidized beds

Science.gov (United States)

Rehmat, A.G.; Patel, J.G.

1987-05-12

An apparatus and process are disclosed for control and maintenance of fluidized beds under non-steady state conditions. An ash removal conduit is provided for removing solid particulates from a fluidized bed separate from an ash discharge conduit in the lower portion of the grate supporting such a bed. The apparatus and process of this invention is particularly suitable for use in ash agglomerating fluidized beds and provides control of the fluidized bed before ash agglomeration is initiated and during upset conditions resulting in stable, sinter-free fluidized bed maintenance. 2 figs.

A distinct boundary between the higher brain's susceptibility to ischemia and the lower brain's resistance.

Directory of Open Access Journals (Sweden)

C Devin Brisson

Full Text Available Higher brain regions are more susceptible to global ischemia than the brainstem, but is there a gradual increase in vulnerability in the caudal-rostral direction or is there a discrete boundary? We examined the interface between `higher` thalamus and the hypothalamus the using live brain slices where variation in blood flow is not a factor. Whole-cell current clamp recording of 18 thalamic neurons in response to 10 min O2/glucose deprivation (OGD revealed a rapid anoxic depolarization (AD from which thalamic neurons do not recover. Newly acquired neurons could not be patched following AD, confirming significant regional thalamic injury. Coinciding with AD, light transmittance (LT imaging during whole-cell recording showed an elevated LT front that initiated in midline thalamus and that propagated into adjacent hypothalamus. However, hypothalamic neurons patched in paraventricular nucleus (PVN, n= 8 magnocellular and 12 parvocellular neurons and suprachiasmatic nucleus (SCN, n= 18 only slowly depolarized as AD passed through these regions. And with return to control aCSF, hypothalamic neurons repolarized and recovered their input resistance and action potential amplitude. Moreover, newly acquired hypothalamic neurons could be readily patched following exposure to OGD, with resting parameters similar to neurons not previously exposed to OGD. Thalamic susceptibility and hypothalamic resilience were also observed following ouabain exposure which blocks the Na(+/K(+ pump, evoking depolarization similar to OGD in all neuronal types tested. Finally, brief exposure to elevated [K(+]o caused spreading depression (SD, a milder, AD-like event only in thalamic neurons so SD generation is regionally correlated with strong AD. Therefore the thalamus-hypothalamus interface represents a discrete boundary where neuronal vulnerability to ischemia is high in thalamus (like more rostral neocortex, striatum, hippocampus. In contrast hypothalamic neurons are

Model of homogeneous nucleus. Total and inelastic cross sections of nucleon-nucleus scattering

International Nuclear Information System (INIS)

Ponomarev, L.A.; Smorodinskaya, N.Ya.

1985-01-01

It is shown that the nucleon-nuckleus scattering amplitude at high energy can be easily calculated by generalization of the nucleon-nucleon scattering amplitude and satisfies a simple factorization relation. As distinct from the Glauber model, the suggested approach makes no use of the nucleonic structure of the nucleus and the hadron-nucleus scattering amplitude is not expressed in terms of hadron-nucleon scattering amplitudes. The energy dependence of total and inelastic cross sections is successfully described for a number of nuclei

Experimental study of flow field characteristics on bed configurations in the pebble bed reactor

International Nuclear Information System (INIS)

Jia, Xinlong; Gui, Nan; Yang, Xingtuan; Tu, Jiyuan; Jia, Haijun; Jiang, Shengyao

2017-01-01

Highlights: • PTV study of flow fields of pebble bed reactor with different configurations are carried out. • Some criteria are proposed to quantify vertical velocity field and flow uniformity. • The effect of different pebble bed configurations is also compared by the proposed criteria. • The displacement thickness is used analogically to analyze flow field characteristics. • The effect of mass flow variation in the stagnated region of the funnel flow is measured. - Abstract: The flow field characteristics are of fundamental importance in the design work of the pebble bed high temperature gas cooled reactor (HTGR). The different effects of bed configurations on the flow characteristics of pebble bed are studied through the PTV (Particle Tracking Velocimetry) experiment. Some criteria, e.g. flow uniformity (σ) and mass flow level (α), are proposed to estimate vertical velocity field and compare the bed configurations. The distribution of the Δθ (angle difference between the individual particle velocity and the velocity vector sum of all particles) is also used to estimate the resultant motion consistency level. Moreover, for each bed configuration, the thickness of displacement is analyzed to measure the effect of the funnel flow zone based on the boundary layer theory. Detailed information shows the quantified characteristics of bed configuration effects on flow uniformity and other characteristics; and the sequence of levels of each estimation criterion is obtained for all bed configurations. In addition, a good design of the pebble bed configuration is suggested and these estimation criteria can be also applied and adopted in testing other geometry designs of pebble bed.

Bed diameter effects and incipient slugging in gas fluidized beds

International Nuclear Information System (INIS)

Agarwal, P.K.

1986-01-01

The coalescence and growth of bubble swarms formed at the distributor of a fluidized bed gives rise to lateral as well as vertical distributions of bubble properties. However, existing models employ average bubble properties obtained largely from semi-empirical considerations. In a recent Paper, the author developed a bubble growth model based on a population balance approach. Analytical expressions were derived for the bubble characteristic distributions and averages. However, the model, developed for unconstrained growth, did not take into account the effect of the bed diameter and the possibility of slugging. In this Paper, the model is extended to take these aspects into account. A slugging criterion is also developed which is expected to be valid for the regime where incipient slugging depends on the bed height as well as the region where bed height does not significantly affect minimum slugging conditions

The Thalamocortical Projection Systems in Primate: An Anatomical Support for Multisensory and Sensorimotor Interplay

Science.gov (United States)

Cappe, Céline; Morel, Anne; Barone, Pascal

2009-01-01

Multisensory and sensorimotor integrations are usually considered to occur in superior colliculus and cerebral cortex, but few studies proposed the thalamus as being involved in these integrative processes. We investigated whether the organization of the thalamocortical (TC) systems for different modalities partly overlap, representing an anatomical support for multisensory and sensorimotor interplay in thalamus. In 2 macaque monkeys, 6 neuroanatomical tracers were injected in the rostral and caudal auditory cortex, posterior parietal cortex (PE/PEa in area 5), and dorsal and ventral premotor cortical areas (PMd, PMv), demonstrating the existence of overlapping territories of thalamic projections to areas of different modalities (sensory and motor). TC projections, distinct from the ones arising from specific unimodal sensory nuclei, were observed from motor thalamus to PE/PEa or auditory cortex and from sensory thalamus to PMd/PMv. The central lateral nucleus and the mediodorsal nucleus project to all injected areas, but the most significant overlap across modalities was found in the medial pulvinar nucleus. The present results demonstrate the presence of thalamic territories integrating different sensory modalities with motor attributes. Based on the divergent/convergent pattern of TC and corticothalamic projections, 4 distinct mechanisms of multisensory and sensorimotor interplay are proposed. PMID:19150924

Interesting correlations among various parameters of charged secondaries in nucleus - nucleus interactions at 4.5 A GeV

International Nuclear Information System (INIS)

Khan, M. Saleem; Shukla, Praveen Prakash; Khushnood, H.

2015-01-01

The study of the characteristic of charged secondaries was the aim of most of the experiments on high energy nucleon-nucleon and nucleus-nucleus collisions. Investigation are carried out on the produced secondary charged particles with a common belief that these particles are more informative about the collisional dynamics and thus, could be effective in revealing the underlying physics of high energy relativistic interactions. So for understanding the mechanism of multiparticle production in high energy hadron-nucleus collisions, the correlations amongst the secondary charged particles are studied. Several workers have attempted to study the multiplicity correlations over widely different incident energies with different projectiles. The AALMT collaboration have also studied the multiplicity correlations in 200 GeV proton-nucleus collisions

Sex Differences in Risk Preference and c-Fos Expression in Paraventricular Thalamic Nucleus of Rats During Gambling Task

Science.gov (United States)

Ishii, Hironori; Onodera, Mariko; Ohara, Shinya; Tsutsui, Ken-Ichiro; Iijima, Toshio

2018-01-01

Different biological requirements between males and females may cause sex differences in decision preference when choosing between taking a risk to get a higher gain or taking a lower but sure gain. Several studies have tested this assumption in rats, however the conclusion remains controversial because the previous real-world like gambling tasks contained a learning component to track a global payoff of probabilistic outcome in addition to risk preference. Therefore, we modified a simple gambling task allowing us to exclude such learning effect, and investigated the sex difference in risk preference of rats and its neural basis. The task required water deprived rats to choose between a risky option which provided four drops of water or no reward at a 50% random chance vs. a sure option which provided predictable amount x (x = 1, 2, 3, 4). The amount and the risk were explicitly instructed so that different choice conditions could be tested trial by trial without re-learning of reward contingency. Although both sexes correctly chose the sure option with the same level of accuracy when the sure option provided the best offer (x = 4), they exhibited different choice performances when two options had the same expected value (x = 2). Males and females both preferred to take risky choices than sure choices (risk seeking), but males were more risk seeking than females. Outcome-history analysis of their choice pattern revealed that females reduced their risk preference after losing risky choices, whereas males did not. Rather, as losses continued, reaction time for subsequent risky choices got shorter in males. Given that significant sex difference features mainly emerged after negative experiences, male and female rats may evaluate an unsuccessful outcome of their decision in different manners. Furthermore, c-Fos expression in the paraventricular nucleus of the thalamus (PV) was higher in the gambling task than for the control task in males while c-fos levels did not

K sup + nucleus total cross sections

Energy Technology Data Exchange (ETDEWEB)

Sawafta, R.

1990-01-01

The scattering of K{sup +} mesons from nuclei has attracted considerable interest in the last few years. The K{sup +} holds a very special position as the weakest of all strongly interaction probes. The average cross section is not larger than about 10 mb at lab momenta below 800 MeV/c, corresponding to a mean free path in the nucleus larger than 5 fm. Thus the K{sup +} is capable of probing the entire volume of the nucleus. Single scattering of the K{sup +} with a nucleon in the nucleus dominates the nuclear scattering, and only small and calculable higher order corrections are needed. The nucleon is a dynamical entity and its internal structure can, in principle, be altered by its surrounding nuclear environment. This work reports an experiment in which the K{sup +} is used to compare the nucleon in the nucleus with a free nucleon.

Microtubules move the nucleus to quiescence.

Science.gov (United States)

Laporte, Damien; Sagot, Isabelle

2014-01-01

The nucleus is a cellular compartment that hosts several macro-molecular machines displaying a highly complex spatial organization. This tight architectural orchestration determines not only DNA replication and repair but also regulates gene expression. In budding yeast microtubules play a key role in structuring the nucleus since they condition the Rabl arrangement in G1 and chromosome partitioning during mitosis through their attachment to centromeres via the kinetochore proteins. Recently, we have shown that upon quiescence entry, intranuclear microtubules emanating from the spindle pole body elongate to form a highly stable bundle that spans the entire nucleus. Here, we examine some molecular mechanisms that may underlie the formation of this structure. As the intranuclear microtubule bundle causes a profound re-organization of the yeast nucleus and is required for cell survival during quiescence, we discuss the possibility that the assembly of such a structure participates in quiescence establishment.

Discontinuous Galerkin finite element method for solving population density functions of cortical pyramidal and thalamic neuronal populations.

Science.gov (United States)

Huang, Chih-Hsu; Lin, Chou-Ching K; Ju, Ming-Shaung

2015-02-01

Compared with the Monte Carlo method, the population density method is efficient for modeling collective dynamics of neuronal populations in human brain. In this method, a population density function describes the probabilistic distribution of states of all neurons in the population and it is governed by a hyperbolic partial differential equation. In the past, the problem was mainly solved by using the finite difference method. In a previous study, a continuous Galerkin finite element method was found better than the finite difference method for solving the hyperbolic partial differential equation; however, the population density function often has discontinuity and both methods suffer from a numerical stability problem. The goal of this study is to improve the numerical stability of the solution using discontinuous Galerkin finite element method. To test the performance of the new approach, interaction of a population of cortical pyramidal neurons and a population of thalamic neurons was simulated. The numerical results showed good agreement between results of discontinuous Galerkin finite element and Monte Carlo methods. The convergence and accuracy of the solutions are excellent. The numerical stability problem could be resolved using the discontinuous Galerkin finite element method which has total-variation-diminishing property. The efficient approach will be employed to simulate the electroencephalogram or dynamics of thalamocortical network which involves three populations, namely, thalamic reticular neurons, thalamocortical neurons and cortical pyramidal neurons. Copyright © 2014 Elsevier Ltd. All rights reserved.

Engineering a thalamo-cortico-thalamic circuit on SpiNNaker: a preliminary study towards modelling sleep and wakefulness

Directory of Open Access Journals (Sweden)

Basabdatta Sen Bhattacharya

2014-05-01

Full Text Available We present a preliminary study of a thalamo-cortico-thalamic (TCT implementation on SpiNNaker (Spiking Neural Network architecture, a brain inspired hardware platform designed to incorporate the inherent biological properties of parallelism, fault tolerance and energy efficiency. These attributes make SpiNNaker an ideal platform for simulating biologically plausible computational models. Our focus in this work is to design a TCT framework that can be simulated on SpiNNaker to mimic dynamical behaviour similar to Electroencephalogram (EEG time and power-spectra signatures in sleep-wake transition. The scale of the model is minimised for simplicity in this proof-of-concept study; thus the total number of spiking neurons is approximately 1000 and represents a `mini-column' of the thalamocortical tissue. All data on model structure, synaptic layout and parameters is inspired from previous studies and abstracted at a level that is appropriate to the aims of the current study as well as computationally suitable for model simulation on a small 4-chip SpiNNaker system. The initial results from selective deletion of synaptic connectivity parameters in the model show similarity with EEG time series characteristics of sleep and wakefulness. These observations provide a positive perspective and a basis for future implementation of a very large scale biologically plausible model of thalamo-cortico-thalamic interactivity---the essential brain circuit that regulates the biological sleep-wake cycle and associated EEG rhythms.

High energy nucleus-nucleus collisions at CERN: Signatures, physical observables and experimental results

International Nuclear Information System (INIS)

Harris, J.W.

1988-02-01

Experimental results on high energy nucleus-nucleus collisions have become available with the recent experiments at CERN utilizing 200 GeV/n oxygen and sulfur beams. Physics motivations for these experiments are presented: a description of predicted signatures for possible formation of a quark-gluon plasma and physical observables that are expected to provide important information for understanding the dynamics of these collisions. A presentation will be made of some of the first experimental results to emerge from this new field. 28 refs., 9 figs

The isospin dependence of the nucleus-nucleus inelastic cross-section at high energy

International Nuclear Information System (INIS)

Rashdan, M.; Farhan, A.M.; Hassib, E.; Kareem, W. Abdel

2006-01-01

The isospin dependence of the nucleus-nucleus inelastic cross-section at high energy is investigated within the multiple scattering theory. The multiple integrals are evaluated by Monte Carlo method as well as by the optical limit approximation of the Glauber model. Calculations are performed for 14-23 N, 16-24 O and 18-26 F isotopes colliding with carbon target around 1 GeV. It is found that rms radii and the density distributions show a halo structure of 22 N, 23 O and 24 F

Effect of bed configuration on pebble flow uniformity and stagnation in the pebble bed reactor

International Nuclear Information System (INIS)

Gui, Nan; Yang, Xingtuan; Tu, Jiyuan; Jiang, Shengyao

2014-01-01

Highlights: • Pebble flow uniformity and stagnation characteristics are very important for HTR-PM. • Arc- and brachistochrone-shaped configuration effects are studied by DEM simulation. • Best bed configurations with uniform flow and no stagnated pebbles are suggested. • Detailed quantified characteristics of bed configuration effects are shown for explanation. - Abstract: Pebble flow uniformity and stagnation characteristics are very important for the design of pebble bed high temperature gas-cooled reactor. Pebble flows inside some specifically designed contraction configurations of pebble bed are studied by discrete element method. The results show the characteristics of stagnation rates, recycling rates, radial distribution of pebble velocity and residence time. It is demonstrated clearly that the bed with a brachistochrone-shaped configuration achieves optimum levels of flow uniformity and recycling rate concentration, and almost no pebbles are stagnated in the bed. Moreover, the optimum choice among the arc-shaped bed configurations is demonstrated too. Detailed information shows the quantified characteristics of bed configuration effects on flow uniformity. In addition, a good design of the pebble bed configuration is suggested

Strangeness and charm production in nucleus-nucleus collisions at beam energies near the thresholds

International Nuclear Information System (INIS)

Senger, P.

2001-01-01

The creation of strangeness and charm in nucleus-nucleus collisions at threshold beam energies is discussed as a probe for compressed baryonic matter. Experimental data on strangeness production at SIS energies indicate that the properties of kaons and antikaons are modified in the dense nuclear medium. An experiment is proposed to explore the QCD phase diagram in the region of highest baryon densities. An important observable will be charm production close to threshold. (orig.)

Visualization of bed material movement in a simulated fluidized bed heat exchanger by neutron radiography

International Nuclear Information System (INIS)

Umekawa, Hisashi; Ozawa, Mamoru; Takenaka, Nobuyuki; Matsubayashi, Masahito

1999-01-01

The bulk movement of fluidized bed material was visualized by neutron radiography by introducing tracers into the bed materials. The simulated fluidized bed consisted of aluminum plates, and the bed material was sand of 99.7% SiO 2 (mean diameter: 0.218 mm, density: 2555 kg/m 3 ). Both materials were almost transparent to neutrons. Then the sand was colored by the contamination of the sand coated by CdSO 4 . Tracer particles of about 2 mm diameter were made by the B 4 C, bonded by the vinyl resin. The tracer was about ten times as large as the particle of fluidized bed material, but the traceability was enough to observe the bed-material bulk movement owing to the large effective viscosity of the fluidized bed. The visualized images indicated that the bubbles and/or wakes were important mechanism of the behavior of the fluidized bed movement

Method and apparatus for a combination moving bed thermal treatment reactor and moving bed filter

Energy Technology Data Exchange (ETDEWEB)

Badger, Phillip C.; Dunn, Jr., Kenneth J.

2015-09-01

A moving bed gasification/thermal treatment reactor includes a geometry in which moving bed reactor particles serve as both a moving bed filter and a heat carrier to provide thermal energy for thermal treatment reactions, such that the moving bed filter and the heat carrier are one and the same to remove solid particulates or droplets generated by thermal treatment processes or injected into the moving bed filter from other sources.

Anti p-nucleus interaction

International Nuclear Information System (INIS)

Peng, J.C.

1986-05-01

Status and future prospects of antiproton-nucleus scattering experiments are presented. These scattering experiments were conducted at antiproton beam momentums of 300 and 600 MeV/c on target nuclei of 6 Li, 12 C, 16 O, 18 O, 40 Ca, 48 Ca, and 208 Pb. Antiproton-proton reactions investigated antiproton-nucleus bound or resonant states in antiproton reactions with d, 6 Li, 12 C, 63 Cu, and 209 Bi. Inelastic scattering experiments investigated the spin-isospin dependence of the NN interactions. 19 refs., 1 fig., 1 tab

Hadron-nucleus interactions with a small target-nucleus excitation

International Nuclear Information System (INIS)

Anzon, Z.V.; Chasnikov, I.Ya.; Shakhova, Ts.I.

1981-01-01

Hadron inelastic interactions in nuclear emulsion with a small target-nucleus excitation in the energy range 7.5-200 GeV have been studied. Possible reasons for the differences in production cross-section for events with even and odd number of S-particles are analysed

Formation, structure, and evolution of boiling nucleus and interfacial tension between bulk liquid phase and nucleus

Science.gov (United States)

Wang, Xiao-Dong; Peng, Xiao-Feng; Tian, Yong; Wang, Bu-Xuan

2005-05-01

In this paper, the concept of the molecular free path is introduced to derive a criterion distinguishing active molecules from inactive molecules in liquid phase. A concept of the critical aggregation concentration (CAC) of active molecules is proposed to describe the physical configuration before the formation of a nucleus during vapor-liquid phase transition. All active molecules exist as monomers when the concentration of active molecules is lower than CAC, while the active molecules will generate aggregation once the concentration of the active molecules reaches CAC. However, these aggregates with aggregation number, N, smaller than five can steadily exist in bulk phase. The other excess active molecules can only produce infinite aggregation and form a critical nucleus of vapor-liquid phase transition. Without any outer perturbation the state point of CAC corresponds to the critical superheated or supercooled state. Meanwhile, a model of two-region structure of a nucleus is proposed to describe nucleus evolution. The interfacial tension between bulk liquid phase and nucleus is dependent of the density gradient in the transition region and varies with the structure change of the transition region. With the interfacial tension calculated using this model, the predicted nucleation rate is very close to the experimental measurement. Furthermore, this model and associated analysis provides solid theoretical evidences to clarify the definition of nucleation rate and understand nucleation phenomenon with the insight into the physical nature.

Fluidised bed combustion system

International Nuclear Information System (INIS)

McKenzie, E.C.

1976-01-01

Fluidized bed combustion systems that facilitates the maintenance of the depth of the bed are described. A discharge pipe projects upwardly into the bed so that bed material can flow into its upper end and escape downwardly. The end of the pipe is surrounded by an enclosure and air is discharged into the enclosure so that material will enter the pipe from within the enclosure and have been cooled in the enclosure by the air discharged into it. The walls of the enclosure may themselves be cooled

On the possible detection of quantum-mechanical interferences between gravitational forces and nucleus-nucleus Coulomb forces

International Nuclear Information System (INIS)

Silveira, R. da

1996-07-01

Possible effects of quantum-mechanical interferences between gravitational forces and the nucleus-nucleus Coulomb interaction are discussed. It is shown that, although very small, these effects could be measured using low energy scattering between identical heavy nuclei, e.g. for the system 208 Pb + 208 Pb (E L = 5 MeV). (author)

WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

Energy Technology Data Exchange (ETDEWEB)

Hansen, E. K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2015-05-06

This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

WTP Pretreatment Facility Potential Design Deficiencies--Sliding Bed and Sliding Bed Erosion Assessment

International Nuclear Information System (INIS)

Hansen, E. K.

2015-01-01

This assessment is based on readily available literature and discusses both Newtonian and non-Newtonian slurries with respect to sliding beds and erosion due to sliding beds. This report does not quantify the size of the sliding beds or erosion rates due to sliding beds, but only assesses if they could be present. This assessment addresses process pipelines in the Pretreatment (PT) facility and the high level waste (HLW) transfer lines leaving the PT facility to the HLW vitrification facility concentrate receipt vessel.

Dynamics of hadron-nucleus interactions

International Nuclear Information System (INIS)

Wallace, S.J.

1981-07-01

Recent progress in diffraction theory shows that proton-nucleus scattering at nonforward angles is dominated by the interference of waves from two or more bright spots. Analytic formulas based on asymptotic theories of diffraction yield valuable new insights into the scattering and these formulas can be readily extended to illuminate the role of dynamical ingredients, i.e., the nucleon-nucleon amplitudes. The governing parameters of the diffraction and some direct connections between the observed cross sections and the input dynamics are reviewed. New information regarding the nucleon-nucleon parameters based on recent phase shift analyses show some systematic differences from the effective NN amplitudes which produce fits to proton-nucleus diffraction data. Recent progress in understanding the role of Δ-isobars in proton-nucleus dynamics is reviewed. 126 references

Oxytocin receptor neurotransmission in the dorsolateral bed nucleus of the stria terminalis facilitates the acquisition of cued fear in the fear-potentiated startle paradigm in rats.

Science.gov (United States)

Moaddab, Mahsa; Dabrowska, Joanna

2017-07-15

Oxytocin (OT) is a hypothalamic neuropeptide that modulates fear and anxiety-like behaviors. Dorsolateral bed nucleus of the stria terminalis (BNST dl ) plays a critical role in the regulation of fear and anxiety, and expresses high levels of OT receptor (OTR). However, the role of OTR neurotransmission within the BNST dl in mediating these behaviors is unknown. Here, we used adult male Sprague-Dawley rats to investigate the role of OTR neurotransmission in the BNST dl in the modulation of the acoustic startle response, as well as in the acquisition and consolidation of conditioned fear using fear potentiated startle (FPS) paradigm. Bilateral intra-BNST dl administration of OT (100 ng) did not affect the acquisition of conditioned fear response. However, intra-BNST dl administration of specific OTR antagonist (OTA), (d(CH 2 ) 5 1 , Tyr(Me) 2 , Thr 4 , Orn 8 , des-Gly-NH 2 9 )-vasotocin, (200 ng), prior to the fear conditioning session, impaired the acquisition of cued fear, without affecting a non-cued fear component of FPS. Neither OTA, nor OT affected baseline startle or shock reactivity during fear conditioning. Therefore, the observed impairment of cued fear after OTA infusion resulted from the specific effect on the formation of cued fear. In contrast to the acquisition, neither OTA nor OT affected the consolidation of FPS, when administered after the completion of fear conditioning session. Taken together, these results reveal the important role of OTR neurotransmission in the BNST dl in the formation of conditioned fear to a discrete cue. This study also highlights the role of the BNST dl in learning to discriminate between threatening and safe stimuli. Copyright © 2017 Elsevier Ltd. All rights reserved.

Bacillus cereus in free-stall bedding.

Science.gov (United States)

Magnusson, M; Svensson, B; Kolstrup, C; Christiansson, A

2007-12-01

To increase the understanding of how different factors affect the bacterial growth in deep sawdust beds for dairy cattle, the microbiological status of Bacillus cereus and coliforms in deep sawdust-bedded free stalls was investigated over two 14-d periods on one farm. High counts of B. cereus and coliforms were found in the entire beds. On average, 4.1 log(10) B. cereus spores, 5.5 log(10) B. cereus, and 6.7 log(10) coliforms per gram of bedding could be found in the upper layers of the sawdust likely to be in contact with the cows' udders. The highest counts of B. cereus spores, B. cereus, and coliforms were found in the bedding before fresh bedding was added, and the lowest immediately afterwards. Different factors of importance for the growth of B. cereus in the bedding material were explored in laboratory tests. These were found to be the type of bedding, pH, and the type and availability of nutrients. Alternative bedding material such as peat and mixtures of peat and sawdust inhibited the bacterial growth of B. cereus. The extent of growth of B. cereus in the sawdust was increased in a dose-dependent manner by the availability of feces. Urine added to different bedding material raised the pH and also led to bacterial growth of B. cereus in the peat. In sawdust, a dry matter content greater than 70% was needed to lower the water activity to 0.95, which is needed to inhibit the growth of B. cereus. In an attempt to reduce the bacterial growth of B. cereus and coliforms in deep sawdust beds on the farm, the effect of giving bedding daily or a full replacement of the beds was studied. The spore count of B. cereus in the back part of the free stalls before fresh bedding was added was 0.9 log units lower in stalls given daily bedding than in stalls given bedding twice weekly. No effect on coliform counts was found. Replacement of the entire sawdust bedding had an effect for a short period, but by 1 to 2 mo after replacement, the counts of B. cereus spores in the

Physiological and morphological characterization of organotypic cocultures of the chick forebrain area MNH and its main input area DMA/DMP.

Science.gov (United States)

Endepols, H; Jungnickel, J; Braun, K

2001-01-01

Cocultures of the learning-relevant forebrain region mediorostral neostriatum and hyperstriatum ventrale (MNH) and its main glutamatergic input area nucleus dorsomedialis anterior thalami/posterior thalami were morphologically and physiologically characterized. Synaptic contacts of thalamic fibers were light- and electron-microscopically detected on MNH neurons by applying the fluorescence tracer DiI-C18(3) into the thalamus part of the coculture. Most thalamic synapses on MNH neurons were symmetric and located on dendritic shafts, but no correlation between Gray-type ultrastructure and dendritic localization was found. Using intracellular current clamp recordings, we found that the electrophysiological properties, such as input resistance, time constant, action potential threshold, amplitude, and duration of MNH neurons, remain stable for over 30 days in vitro. Pharmacological blockade experiments revealed glutamate as the main neurotransmitter of thalamic synapses on MNH neurons, which were also found on inhibitory neurons. High frequency stimulation of thalamic inputs evoked synaptic potentiation in 22% of MNH neurons. The results indicate that DMA/DMP-MNH cocultures, which can be maintained under stable conditions for at least 4 weeks, provide an attractive in vitro model for investigating synaptic plasticity in the avian brain.

Transport of glutathione into the nucleus.

Science.gov (United States)

Queval, Guillaume; Foyer, Christine

2014-10-01

The tripeptide thiol glutathione (GSH) is present in the nucleus of plant and animal cells. However, the functions of GSH in the nucleus remain poorly characterised. GSH appears to become sequestered in the nucleus at the early stages of the cell cycle. As part of our search for proteins that may be involved in GSH transport into the nucleus, we studied the functions of the nucleoporin called Alacrima Achalasia aDrenal Insufficiency Neurologic disorder (ALADIN). ALADIN is encoded by the Achalasia-Addisonianism-Alacrimia (AAAS) gene in mammalian cells. Defects in ALADIN promote adrenal disorders and lead to the triple A syndrome in humans. The ALADIN protein localizes to the nuclear envelope in Arabidopsis thaliana and interacts with other components of the nuclear pore complex (NPC). We characterised the functions of the ALADIN protein in an Arabidopsis thaliana T-DNA insertion knockout mutant, which shows slow growth compared to the wild type. Copyright © 2014. Published by Elsevier Inc.

Astronomical cycle origin of bedded chert: A middle Triassic bedded chert sequence, Inuyama, Japan

Science.gov (United States)

Ikeda, Masayuki; Tada, Ryuji; Sakuma, Hironobu

2010-09-01

Astronomical forcing is one of the main drivers of climate change, and astronomical cyclicity recorded in sediments provides a clue to understand the dynamics of the global climate system. Bedded cherts consist of rhythmic alternations of chert and shale beds. Although previous studies have hypothesized that the origin of bedded chert is related to astronomical cycles (e.g. Fischer, 1976; Hori et al., 1993), conclusive proof remains elusive. To explore this possibility, we established a continuous, high-resolution lithostratigraphy of middle Triassic bedded chert in Central Japan. The average duration of each chert-shale couplet is 20 kyr, similar to that of the precession cycle. Spectral analysis of a bed number series of thickness variations in chert beds was performed assuming that each chert-shale couplet represents a 20-kyr precession cycle. The results reveal cycles involving approximately 200, 20, 5, and 2-3 beds, corresponding to periodicities of approximately 4000, 400, 100, and 40-60 kyr, respectively. By further assuming that the 20-bed cycle represents a 405-kyr eccentricity cycle of constant and stable periodicity, we converted the bed number series to a time series. Spectral analysis of the time series revealed distinct periodicities of 3600, 117, 97, and 38 kyr, in addition to 405 kyr. Besides 3600 kyr, these periodicities agree well with the 120, 95, and 37 kyr periodicities for eccentricity cycles and the obliquity cycle during the Triassic. Moreover, we detected amplitude modulation of the approximately 100-kyr cycle of thickness variations in chert beds with a 405-kyr periodicity, which may correspond to amplitude modulation of 100-kyr climatic precession cycle with the 405-kyr periodicity. The approximately 3600-kyr periodicity described above and 1800-kyr periodicity manifested as the amplitude modulation of the 405-kyr cycle are correlated to present-day long-term eccentricity cycles of 2400 and 4800 kyr evolved by chaotic behavior of solar

Thalamus and Language: What do we know from vascular and degenerative pathologies.

Science.gov (United States)

Moretti, Rita; Caruso, Paola; Crisman, Elena; Gazzin, Silvia

2018-01-01

Language is a complex cognitive task that is essential in our daily life. For decades, researchers have tried to understand the different role of cortical and subcortical areas in cerebral language representations and language processing. Language-related cortical zones are richly interconnected with other cortical regions (particularly via myelinated fibre tracts), but they also participate in subcortical feedback loops within the basal ganglia (caudate nucleus and putamen) and thalamus. The most relevant thalamic functions are the control and adaptation of cortico-cortical connectivity and bandwidth for information exchange. Despite having the knowledge of thalamic and basal ganglionic involvement in linguistic operations, the specific functions of these subcortical structures remain rather controversial. The aim of this study is to better understand the role of thalamus in language network, exploring the functional configuration of basal network components. The language specificity of subcortical supporting activity and the associated clinical features in thalamic involvement are also highlighted.

Application of CaO-Based Bed Material for Dual Fluidized Bed Steam Biomass Gasification

Science.gov (United States)

Koppatz, S.; Pfeifer, C.; Kreuzeder, A.; Soukup, G.; Hofbauer, H.

Gasification of biomass is a suitable option for decentralized energy supply based on renewable sources in the range of up to 50 MW fuel input. The paper presents the dual fluidized bed (DFB) steam gasification process, which is applied to generate high quality and nitrogen-free product gas. Essential part of the DFB process is the bed material used in the fluidized reactors, which has significant impact on the product gas quality. By the use of catalytically active bed materials the performance of the overall process is increased, since the bed material favors reactions of the steam gasification. In particular, tar reforming reactions are favored. Within the paper, the pilot plant based on the DFB process with 100kW fuel input at Vienna University of Technology, Austria is presented. Actual investigations with focus on CaO-based bed materials (limestone) as well as with natural olivine as bed material were carried out at the pilot plant. The application of CaO-based bed material shows mainly decreased tar content in the product gas in contrast to experiments with olivine as bed material. The paper presents the results of steam gasification experiments with limestone and olivine, whereby the product gas composition as well as the tar content and the tar composition are outlined.

Nucleus management with irrigating vectis

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Srinivasan Aravind

2009-01-01

Full Text Available The main objective in modern cataract surgery is to achieve a better unaided visual acuity with rapid post-surgical recovery and minimal surgery-related complications. Early visual rehabilitation and better unaided vision can be achieved only by reducing the incision size. In manual small incision cataract surgery (MSICS, incision is between 5.5 to 7 mm. Once the nucleus is prolapsed into the anterior chamber, it can be extracted through the tunnel. Nucleus extraction with an irrigating vectis is a very simple technique, which combines mechanical and hydrostatic forces to express out the nucleus. This technique is time-tested with good results and more than 95% of nuclei in MSICS are extracted in this way offering all the merits of phacoemulsification with the added benefits of having wider applicability, better safety, shorter learning curve and lower cost.

Biodegradation of phenolic waste liquors in stirred-tank, packed-bed, and fluidized-bed bioreactors

Energy Technology Data Exchange (ETDEWEB)

Holladay, D W; Hancher, G W; Chilcote, D D; Scott, C D

1978-11-01

The biological degradation of phenolic scrub liquors similar to those that arise in coal conversion processes was studied for symbiotic bacterial populations contained in a continuously stirred tank bioreactor, a three-phase packed-bed bioreactor, and a three-phase, fluidized-bed bioreactor. The conversions of phenol compounds were comparable in the three-phase, packed-bed bioreactor and the continuously stirred tank bioreactor; however, the packed-bed bioreactor degradation rates were as much as twice those in the continuously stirred tank bioreactor, and packed-bed bioreactor retention times were as low as one- tenth those of the continuously stirred tank bioreactors (minimum time was 12 hours).

Thalamic Functional Connectivity in Mild Traumatic Brain Injury: Longitudinal Associations With Patient-Reported Outcomes and Neuropsychological Tests.

Science.gov (United States)

Banks, Sarah D; Coronado, Rogelio A; Clemons, Lori R; Abraham, Christine M; Pruthi, Sumit; Conrad, Benjamin N; Morgan, Victoria L; Guillamondegui, Oscar D; Archer, Kristin R

2016-08-01

(1) To examine differences in patient-reported outcomes, neuropsychological tests, and thalamic functional connectivity (FC) between patients with mild traumatic brain injury (mTBI) and individuals without mTBI and (2) to determine longitudinal associations between changes in these measures. Prospective observational case-control study. Academic medical center. A sample (N=24) of 13 patients with mTBI (mean age, 39.3±14.0y; 4 women [31%]) and 11 age- and sex-matched controls without mTBI (mean age, 37.6±13.3y; 4 women [36%]). Not applicable. Resting state FC (3T magnetic resonance imaging scanner) was examined between the thalamus and the default mode network, dorsal attention network, and frontoparietal control network. Patient-reported outcomes included pain (Brief Pain Inventory), depressive symptoms (Patient Health Questionnaire-9), posttraumatic stress disorder ([PTSD] Checklist - Civilian Version), and postconcussive symptoms (Rivermead Post-Concussion Symptoms Questionnaire). Neuropsychological tests included the Delis-Kaplan Executive Function System Tower test, Trails B, and Hotel Task. Assessments occurred at 6 weeks and 4 months after hospitalization in patients with mTBI and at a single visit for controls. Student t tests found increased pain, depressive symptoms, PTSD symptoms, and postconcussive symptoms; decreased performance on Trails B; increased FC between the thalamus and the default mode network; and decreased FC between the thalamus and the dorsal attention network and between the thalamus and the frontoparietal control network in patients with mTBI as compared with controls. The Spearman correlation coefficient indicated that increased FC between the thalamus and the dorsal attention network from baseline to 4 months was associated with decreased pain and postconcussive symptoms (corrected P<.05). Findings suggest that alterations in thalamic FC occur after mTBI, and improvements in pain and postconcussive symptoms are correlated with

Bed and bed-site reuse by western lowland gorillas (Gorilla g. gorilla) in Moukalaba-Doudou National Park, Gabon.

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Iwata, Yuji; Ando, Chieko

2007-01-01

In this paper we describe bed (nest) and bed-site reuse by western lowland gorillas (Gorilla g. gorilla) in Moukalaba-Doudou National Park, south-eastern Gabon. During an eight-month study 44 bed sites and 506 beds were found. Among these, 38.6% of bed sites and 4.1% of beds were reused. We analyzed the monthly frequency of bed-site reuse in relation to rainfall, fruit abundance, and fruit consumption by the gorillas. The different frequency of bed-site reuse in the rainy and dry seasons was not significant. More bed-site reuse was observed during the fruiting season than during the non-fruiting season. Results from fecal analysis suggested that gorillas ate more fruit in the fruiting season than in the non-fruiting season. The frugivorous diet of western gorillas may possibly cause gorillas to stay in some areas and, consequently, reuse their bed sites. Reuse of bed sites by gorillas suggests their frequent return to an area where preferred fruit is readily available. A higher percentage of arboreal beds may also affect bed-site reuse, because of the shortage of bed material.

Neuropeptide Y in the central nucleus of amygdala regulates the anxiolytic effect of agmatine in rats.

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Taksande, Brijesh G; Kotagale, Nandkishor R; Gawande, Dinesh Y; Bharne, Ashish P; Chopde, Chandrabhan T; Kokare, Dadasaheb M

2014-06-01

In the present study, modulation of anxiolytic action of agmatine by neuropeptide Y (NPY) in the central nucleus of amygdala (CeA) is evaluated employing Vogel's conflict test (VCT) in rats. The intra-CeA administration of agmatine (0.6 and 1.2µmol/rat), NPY (10 and 20pmol/rat) or NPY Y1/Y5 receptors agonist [Leu(31), Pro(34)]-NPY (30 and 60pmol/rat) significantly increased the number of punished drinking licks following 15min of treatment. Combination treatment of subeffective dose of NPY (5pmol/rat) or [Leu(31), Pro(34)]-NPY (15pmol/rat) and agmatine (0.3µmol/rat) produced synergistic anxiolytic-like effect. However, intra-CeA administration of selective NPY Y1 receptor antagonist, BIBP3226 (0.25 and 0.5mmol/rat) produced anxiogenic effect. In separate set of experiment, pretreatment with BIBP3226 (0.12mmol/rat) reversed the anxiolytic effect of agmatine (0.6µmol/rat). Furthermore, we evaluated the effect of intraperitoneal injection of agmatine (40mg/kg) on NPY-immunoreactivity in the nucleus accumbens shell (AcbSh), lateral part of bed nucleus of stria terminalis (BNSTl) and CeA. While agmatine treatment significantly decreased the fibers density in BNSTl, increase was noticed in AcbSh. In addition, agmatine reduced NPY-immunoreactive cells in the AcbSh and CeA. Immunohistochemical data suggest the enhanced transmission of NPY from the AcbSh and CeA. Taken together, this study suggests that agmatine produced anxiolytic effect which might be regulated via modulation of NPYergic system particularly in the CeA. Copyright © 2013 Elsevier B.V. and ECNP. All rights reserved.

The effect of vibration on bed voidage behaviors in fluidized beds with large particles

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H. Jin

2007-09-01

Full Text Available The effects of vibration parameters, operating conditions and material properties on bed voidage were investigated using an optical fiber probe approach in a vibrating fluidized bed with a diameter of 148 mm. Variables studied included frequency (0-282 s-1, amplitude (0 mm-1 mm, bed height (0.1 m-0.4 m as well as four kinds of particles (belonging to Geldart's B and D groups. The axial and radial voidage distribution with vibration is compared with that without vibration, which shows vibration can aid in the fluidization behaviors of particles. For a larger vibration amplitude, the vibration seriously affects bed voidage. The vibration energy can damp out for particle layers with increasing the bed height. According to analysis of experimental data, an empirical correlation for predicting bed voidage, giving good agreement with the experimental data and a deviation within ±15%, was proposed.

Open-nucleus theory for beef cattle breeding systems: A revisitation

International Nuclear Information System (INIS)

Recami, E.; Packer, I.U.; Tenorio Vasconselos, M.

1990-07-01

A theoretical model for Open-Nucleus Systems is herein described in the case of beef cattle breeding. One of the starting points is the observation that the majority of the standard theoretical models for open-nucleus breeding systems were constructed for the case of discrete generations, i.e. for the cases in which the dam average fertility coefficient is f>2. In the case of cattle herds, when only a fraction of the breeding dams can be replaced, it is therefore worthwhile to build up anew a rather rigorous theoretical model, with overlapping generations, and check its predictions. Namely, we apply the new formulae - explicitly depending on β F , ν F , ν M , K and R - to the system in which all breeding sires are in the Nucleus (and are reared in the nucleus itself), and are mated to both Nucleus and Base dams via artificial insemination. Optimal system design has been looked for by the NAG and MINOS computation programs, operated on Vax computers. Opening the nucleus in this situation results to be very effective since the (optimum) asymptotic genetic gain per generation for ''closed nucleus'' systems (x=0) results to be, when e.g. R≡F/M≅200, more than 40% lower than the (optimum) asymptotic genetic gain, G*, for open nucleus systems. Optimal design corresponds to: (i) having a fraction p≅16% of the female population in the nucleus; (ii) replacing practically all the (nucleus) breeding sires by the best (nucleus born) males: ν M =97/98%; (iii) using for dam replacement all (b≅100%) the (base and nucleus born) females; (iv) implementing a high upward gene migration (x≅80%), while all the surplus nucleus-born females are to be used as base replacements. This corresponds to replace, at each generation, also almost all the nucleus dams (ν F ≅95/100%), and the largest possible fraction of base dams (β F ≅30%, a value changing with p). 17 refs

Calculations of nucleus-nucleus microscopic optical potentials at intermediate energies

International Nuclear Information System (INIS)

Hanna, K.M.; Kuhtina, I.N.; Lukyanov, K.V.; Lukyanov, V.K.; Zemlyanaya, E.V.; Slowinski, B.

2006-01-01

Three types of microscopic nucleus-nucleus optical potentials are constructed using three patterns for their real and imaginary parts. Two of these patterns are the real V H and imaginary W H parts of the potential which reproduces the high-energy amplitude of scattering in the microscopic Glauber-Sitenko theory. Another template VDF is calculated within the standard double-folding model with the exchange term included. For either of the three tested potentials, the contribution of real and imaginary patterns is adjusted by introducing two fitted factors. Correspondingly, using numerical code ECIS, the elastic differential cross-sections were fitted to the experimental data on scattering of the 16,17 O heavy-ions at about hundred Mev/nucleon on various target-nuclei. The relativization effect is also included. The tables of the obtained factors which renormalize the strengths of the real and (or) imaginary parts of the calculated microscopic potentials are given

The effects of Thalamic Deep Brain Stimulation on speech dynamics in patients with Essential Tremor: An articulographic study.

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Doris Mücke

Full Text Available Acoustic studies have revealed that patients with Essential Tremor treated with thalamic Deep Brain Stimulation (DBS may suffer from speech deterioration in terms of imprecise oral articulation and reduced voicing control. Based on the acoustic signal one cannot infer, however, whether this deterioration is due to a general slowing down of the speech motor system (e.g., a target undershoot of a desired articulatory goal resulting from being too slow or disturbed coordination (e.g., a target undershoot caused by problems with the relative phasing of articulatory movements. To elucidate this issue further, we here investigated both acoustics and articulatory patterns of the labial and lingual system using Electromagnetic Articulography (EMA in twelve Essential Tremor patients treated with thalamic DBS and twelve age- and sex-matched controls. By comparing patients with activated (DBS-ON and inactivated stimulation (DBS-OFF with control speakers, we show that critical changes in speech dynamics occur on two levels: With inactivated stimulation (DBS-OFF, patients showed coordination problems of the labial and lingual system in terms of articulatory imprecision and slowness. These effects of articulatory discoordination worsened under activated stimulation, accompanied by an additional overall slowing down of the speech motor system. This leads to a poor performance of syllables on the acoustic surface, reflecting an aggravation either of pre-existing cerebellar deficits and/or the affection of the upper motor fibers of the internal capsule.

Loading and Unloading Weaned Pigs: Effects of Bedding Types, Ramp Angle, and Bedding Moisture

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Arlene Garcia

2014-12-01

Full Text Available The use of non-slip surfaces during loading and unloading of weaned pigs plays an important role in animal welfare and economics of the pork industry. Currently, the guidelines available only suggest the use of ramps below 20° to load and unload pigs. Three ramp angles (0°, 10° or 20°, five bedding materials (nothing, sand, feed, wood shavings or wheat straw hay, two moistures (dry or wet bedding; >50% moisture over two seasons (>23.9 °C summer, <23.9 °C winter were assessed for slips/falls/vocalizations (n = 6,000 pig observations. “Score” was calculated by the sum of slips, falls, and vocalizations. With the exception of using feed as a bedding, all beddings provided some protection against elevated slips, falls, and vocalizations (P < 0.01. Providing bedding reduced (P < 0.05 scores regardless of whether the bedding was dry or wet. Scores increased as the slope increased (P < 0.01. Provision of bedding, other than feed, at slopes greater than zero, decreased slips, falls and vocalizations. The total time it took to load and unload pigs was

Experimental studies on the coolability of packed beds. Flooding of hot dry packed beds

International Nuclear Information System (INIS)

Leininger, S.; Kulenovic, R.; Laurien, E.

2013-01-01

In case of a severe accident in a nuclear power plant meltdown of the reactor core can occur and form a packed bed in the lower plenum of the reactor pressure vessel (RPV) after solidification due to contact with water. The removal of after-heat and the long-term coolability is of essential interest. The efficient injection of cooling water into the packed bed has to be assured without endangering the structural integrity of the reactor pressure vessel. The experiments performed aimed to study the dry-out and the quenching (flooding) of hot dry packed beds. Two different inflow variants, bottom- and top-flooding including the variation of the starting temperature of the packed bed and the injection rate were studied. In case of bottom flooding the quenching time increases with increasing packed bed temperature and decreasing injection rate. In case of top flooding the flow pattern is more complex, in a first phase the water flows preferentially toward the RPV wall, the flow paths conduct the water downwards. The flow resistance of the packed bed increases with increasing bed temperatures. The quenching temperatures increase significantly above average.

The momentum distribution inside nucleus

International Nuclear Information System (INIS)

Fujita, T.

1985-01-01

Discussions are made on several reactions which can determine the momentum distribution inside nucleus. The first reaction discussed is the high energy heavy ion collision. This reaction involves many nucleons which interact strongly. Therefore, one must be careful for any possible final state interactions. The expression for the single particle momentum distribution is given. And it can be said that the expression is consistent with the description of the energetic neutrons from muon capture by heavy nucleus. The best way to determine the momentum distribution would be the lepton-nucleus scattering since it does not involve the strong interaction in the initial channel. Another reaction discussed is the backward proton production, which is governed by quite complicated reaction processes. Therefore, the determination of the momentum distribution is only indirect. Noverthless, it is found that this reaction presents a very interesting and important information on the momentum distribution. (Aoki, K.)

Environmental protection stability of river bed and banks using convex, concave, and linear bed sills.

Science.gov (United States)

Keshavarzi, Alireza; Noori, Lila Khaje

2010-12-01

River bed scourings are a major environmental problem for fish and aquatic habitat resources. In this study, to prevent river bed and banks from scouring, different types of bed sills including convex, concave and linear patterns were installed in a movable channel bed in a laboratory flume. The bed sills were tested with nine different arrangements and under different flow conditions. To find the most effective bed sill pattern, the scouring depth was measured downstream of the bed sill for a long experimental duration. The scour depth was measured at the middle and at the end of each experimental test for different ratios of the arch radius to the channel width [r/w]. The experimental results indicated that the convex pattern with r/w=0.35 produced minimum bed scouring depth at the center line whereas the concave pattern with r/w=0.23 produced the minimum scour depth at the wall banks. Therefore, the convex pattern was the most effective configuration for prevention of scouring at the center line of the river while the concave pattern was very effective to prevent scouring at the river banks. These findings can be suggested to be used in practical applications.

Long-Term Potentiation in the Motor Cortex

Science.gov (United States)

Iriki, Atsushi; Pavlides, Constantine; Keller, Asaf; Asanuma, Hiroshi

1989-09-01

Long-term potentiation (LTP) is a model for learning and memory processes. Tetanic stimulation of the sensory cortex produces LTP in motor cortical neurons, whereas tetanization of the ventrolateral nucleus of the thalamus, which also projects to the motor cortex, does not. However, after simultaneous high-frequency stimulation of both the sensory cortex and the ventrolateral nucleus of the thalamus, LTP of thalamic input to motor cortical neurons is induced. This associative LTP occurs only in neurons in the superficial layers of the motor cortex that receive monosynaptic input from both the sensory cortex and the ventrolateral nucleus of the thalamus. Associative LTP in the motor cortex may constitute a basis for the retention of motor skills.

Structural dynamics of the cell nucleus

Science.gov (United States)

Wiegert, Simon; Bading, Hilmar

2011-01-01

Neuronal morphology plays an essential role in signal processing in the brain. Individual neurons can undergo use-dependent changes in their shape and connectivity, which affects how intracellular processes are regulated and how signals are transferred from one cell to another in a neuronal network. Calcium is one of the most important intracellular second messengers regulating cellular morphologies and functions. In neurons, intracellular calcium levels are controlled by ion channels in the plasma membrane such as NMDA receptors (NMDARs), voltage-gated calcium channels (VGCCs) and certain α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs) as well as by calcium exchange pathways between the cytosol and internal calcium stores including the endoplasmic reticulum and mitochondria. Synaptic activity and the subsequent opening of ligand and/or voltage-gated calcium channels can initiate cytosolic calcium transients which propagate towards the cell soma and enter the nucleus via its nuclear pore complexes (NPCs) embedded in the nuclear envelope. We recently described the discovery that in hippocampal neurons the morphology of the nucleus affects the calcium dynamics within the nucleus. Here we propose that nuclear infoldings determine whether a nucleus functions as an integrator or detector of oscillating calcium signals. We outline possible ties between nuclear mophology and transcriptional activity and discuss the importance of extending the approach to whole cell calcium signal modeling in order to understand synapse-to-nucleus communication in healthy and dysfunctional neurons. PMID:21738832

Strangeness production in nucleus-nucleus collisions: An experimental review

International Nuclear Information System (INIS)

Odyniec, G.

1990-12-01

In experiments with oxygen (60 and 200 GeV/N) and sulphur (200 GeV/N) ions at CERNSPS, large energy densities of the order of 2--3 GeV/fm 3 have been observed, which according to QCD calculations, satisfy necessary conditions for the formation of a quark gluon plasma (QGP) phase. Under such conditions, colour would no longer be confined to hadronic dimensions, and quarks and gluons will propagate freely throughout an extended volume. Somehow lower energy densities, of the order of 0.7--1 GeV/fm 3 , were observed in AGS experiments with 15 GeV/N silicon beams and heavy targets. These energy densities might be adequate for investigations of the pre-equilibrium stage, during which the momentum space distribution has been degradated from its initial value but is not yet thermal. First experimental results, available now, show promise of seeing signs of a new phase of matter. In this review the current status of the selective experimental results on strange-particle production, which are relevant to equilibration and QGP formation in nucleus-nucleus collisions, is presented

Applying the elastic model for various nucleus-nucleus fusion

International Nuclear Information System (INIS)

HASSAN, G.S.; RAGAB, H.S.; SEDDEEK, M.K.

2000-01-01

The Elastic Model of two free parameters m,d given by Scalia has been used for wider energy regions to fit the available experimental data for potential barriers and cross sections. In order to generalize Scalia's formula in both sub- and above-barrier regions, we calculated m, d for pairs rather than those given by Scalia and compared the calculated cross sections with the experimental data. This makes a generalization of the Elastic Model in describing fusion process. On the other hand, Scalia's range of interacting systems was 24 ≤ A ≤194 where A is the compound nucleus mass number. Our extension of that model includes an example of the pairs of A larger than his final limit aiming to make it as a general formula for any type of reactants: light, intermediate or heavy systems. A significant point is the comparison of Elastic Model calculations with the well known methods studying complete fusion and compound nucleus formation, namely with the resultants of using Proximity potential with either Sharp or Smooth cut-off approximations

The effect of bed non-uniformities and porosity of particles on dryout in boiling particle beds

International Nuclear Information System (INIS)

Macbeth, R.V.; Mogford, D.J.; Willshire, S.J.

1988-03-01

This report relates to an on-going experimental programme concerned with the coolability of beds of reactor core debris or rubble immersed in a liquid coolant, as might occur in an accident situation. The objectives are to develop experimental techniques, improve the understanding of bed cooling mechanisms, determine dry-out limitations of various bed configurations and particle shapes and sizes and devise ways of improving bed coolability. The report concentrates on a recently discovered effect on bed coolability of particle porosity, such as exists in fragmented UO 2 fuel pellets. It is shown that porosity can lower bed dry-out powers by a factor of 4 or 5. A mechanism which explains the effect is presented. The report also gives results of bed non-uniformities obtained by mixing glass particles with the dielectrically heated 'ferrite' particles used in the experiments. (author)

99mTc-HMPAO SPECT thalamic blood flow study in migraine

International Nuclear Information System (INIS)

Zhang Zhijian; Steiner, T.J.

1995-01-01

The changes of blood flow in the thalamic of migraineurs by 99m Tc-HMPAO SPECT imaging are investigated. 60 cases with migraine were performed by Novo 810 high-resolution SPECT 30 minutes after injection of 99m Tc-HMPAO. The quantitative analysis of SPECT data was based on the irregular ROI% uptake normalized to total slice method. There were significantly increased mean % uptake values in migraine with aura (259.1 +-17.1), and more significantly in those who experienced hemisensory symptoms and hemiparesis during aura (263.8 +- 17.2), compared to that of migraine without aura (249.1 +- 14.9), but there were not statistically significant difference between migraine with only visual disturbance during aura (255.1 +- 16.4) and without aura. The possible explanations for the increased mean % uptake values in migraineurs who experienced hemisensory symptoms and hemiparesis during aura are: (1) the reactive postischemic hyperemia. (2) excepting thalamus, the regional blood flow was decreased. (3) the secondary phenomenon to the various neurogenic and chemical stimuli

GluN2B-containing NMDA receptors blockade rescues bidirectional synaptic plasticity in the bed nucleus of the stria terminalis of cocaine self-administering rats.

Science.gov (United States)

deBacker, Julian; Hawken, Emily R; Normandeau, Catherine P; Jones, Andrea A; Di Prospero, Cynthia; Mechefske, Elysia; Gardner Gregory, James; Hayton, Scott J; Dumont, Éric C

2015-01-01

Drugs of abuse have detrimental effects on homeostatic synaptic plasticity in the motivational brain network. Bidirectional plasticity at excitatory synapses helps keep neural circuits within a functional range to allow for behavioral flexibility. Therefore, impaired bidirectional plasticity of excitatory synapses may contribute to the behavioral hallmarks of addiction, yet this relationship remains unclear. Here we tracked excitatory synaptic strength in the oval bed nucleus of the stria terminalis (ovBNST) using whole-cell voltage-clamp recordings in brain slices from rats self-administering sucrose or cocaine. In the cocaine group, we measured both a persistent increase in AMPA to NMDA ratio (A:N) and slow decay time of NMDA currents throughout the self-administration period and after withdrawal from cocaine. In contrast, the sucrose group exhibited an early increase in A:N ratios (acquisition) that returned toward baseline values with continued self-administration (maintenance) and after withdrawal. The sucrose rats also displayed a decrease in NMDA current decay time with continued self-administration (maintenance), which normalized after withdrawal. Cocaine self-administering rats exhibited impairment in NMDA-dependent long-term depression (LTD) that could be rescued by GluN2B-containing NMDA receptor blockade. Sucrose self-administering rats demonstrated no impairment in NMDA-dependent LTD. During the maintenance period of self-administration, in vivo (daily intraperitoneally for 5 days) pharmacologic blockade of GluN2B-containing NMDA receptors did not reduce lever pressing for cocaine. However, in vivo GluN2B blockade did normalize A:N ratios in cocaine self-administrating rats, and dissociated the magnitude of ovBNST A:N ratios from drug-seeking behavior after protracted withdrawal. Altogether, our data demonstrate when and how bidirectional plasticity at ovBNST excitatory synapses becomes dysfunctional with cocaine self-administration and that NMDA

Corticotropin Releasing Factor in the Bed Nucleus of the Stria Terminalis in Socially Defeated and Non-stressed Mice with a History of Chronic Alcohol Intake

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Lucas Albrechet-Souza

2017-10-01

Full Text Available Stress exposure has been identified as one risk factor for alcohol abuse that may facilitate the transition from social or regulated use to the development of alcohol dependence. Preclinical studies have shown that dysregulation of the corticotropin releasing factor (CRF neurotransmission has been implicated in stress-related psychopathologies such as depression and anxiety, and may affect alcohol consumption. The bed nucleus of the stria terminalis (BNST contains CRF-producing neurons which seem to be sensitive to stress. In this study, adult male C57BL/6 mice previously defeated in resident-intruder confrontations were evaluated in the elevated plus-maze and tail suspension test. Mice were also tested for sweet solution intake before and after social stress. After having had continuous access to ethanol (20% weight/volume for 4 weeks, control and stressed mice had CRF type 1 (CRFR1 or type 2 (CRFR2 receptor antagonists infused into the BNST and then had access to ethanol for 24 h. In separate cohorts of control and stressed mice, we assessed mRNA levels of BNST CRF, CRFR1 and CRFR2. Stressed mice increased their intake of sweet solution after ten sessions of social defeat and showed reduced activity in the open arms of the elevated plus-maze. When tested for ethanol consumption, stressed mice persistently drank significantly more than controls during the 4 weeks of access. Also, social stress induced higher BNST CRF mRNA levels. The selective blockade of BNST CRFR1 with CP376,395 effectively reduced alcohol drinking in non-stressed mice, whereas the selective CRFR2 antagonist astressin2B produced a dose-dependent increase in ethanol consumption in both non-stressed controls and stressed mice. The 10-day episodic defeat stress used here elicited anxiety- but not depressive-like behaviors, and promoted an increase in ethanol drinking. CRF-CRFR1 signaling in the BNST seems to underlie ethanol intake in non-stressed mice, whereas CRFR2 modulates

Corticotropin Releasing Factor in the Bed Nucleus of the Stria Terminalis in Socially Defeated and Non-stressed Mice with a History of Chronic Alcohol Intake.

Science.gov (United States)

Albrechet-Souza, Lucas; Viola, Thiago W; Grassi-Oliveira, Rodrigo; Miczek, Klaus A; de Almeida, Rosa M M

2017-01-01

Stress exposure has been identified as one risk factor for alcohol abuse that may facilitate the transition from social or regulated use to the development of alcohol dependence. Preclinical studies have shown that dysregulation of the corticotropin releasing factor (CRF) neurotransmission has been implicated in stress-related psychopathologies such as depression and anxiety, and may affect alcohol consumption. The bed nucleus of the stria terminalis (BNST) contains CRF-producing neurons which seem to be sensitive to stress. In this study, adult male C57BL/6 mice previously defeated in resident-intruder confrontations were evaluated in the elevated plus-maze and tail suspension test. Mice were also tested for sweet solution intake before and after social stress. After having had continuous access to ethanol (20% weight/volume) for 4 weeks, control and stressed mice had CRF type 1 (CRFR1) or type 2 (CRFR2) receptor antagonists infused into the BNST and then had access to ethanol for 24 h. In separate cohorts of control and stressed mice, we assessed mRNA levels of BNST CRF, CRFR1 and CRFR2 . Stressed mice increased their intake of sweet solution after ten sessions of social defeat and showed reduced activity in the open arms of the elevated plus-maze. When tested for ethanol consumption, stressed mice persistently drank significantly more than controls during the 4 weeks of access. Also, social stress induced higher BNST CRF mRNA levels. The selective blockade of BNST CRFR1 with CP376,395 effectively reduced alcohol drinking in non-stressed mice, whereas the selective CRFR2 antagonist astressin2B produced a dose-dependent increase in ethanol consumption in both non-stressed controls and stressed mice. The 10-day episodic defeat stress used here elicited anxiety- but not depressive-like behaviors, and promoted an increase in ethanol drinking. CRF-CRFR1 signaling in the BNST seems to underlie ethanol intake in non-stressed mice, whereas CRFR2 modulates alcohol

Nucleus-size pinning for determination of nucleation free-energy barriers and nucleus geometry

Science.gov (United States)

Sharma, Abhishek K.; Escobedo, Fernando A.

2018-05-01

Classical Nucleation Theory (CNT) has recently been used in conjunction with a seeding approach to simulate nucleation phenomena at small-to-moderate supersaturation conditions when large free-energy barriers ensue. In this study, the conventional seeding approach [J. R. Espinosa et al., J. Chem. Phys. 144, 034501 (2016)] is improved by a novel, more robust method to estimate nucleation barriers. Inspired by the interfacial pinning approach [U. R. Pedersen, J. Chem. Phys. 139, 104102 (2013)] used before to determine conditions where two phases coexist, the seed of the incipient phase is pinned to a preselected size to iteratively drive the system toward the conditions where the seed becomes a critical nucleus. The proposed technique is first validated by estimating the critical nucleation conditions for the disorder-to-order transition in hard spheres and then applied to simulate and characterize the highly non-trivial (prolate) morphology of the critical crystal nucleus in hard gyrobifastigia. A generalization of CNT is used to account for nucleus asphericity and predict nucleation free-energy barriers for gyrobifastigia. These predictions of nuclei shape and barriers are validated by independent umbrella sampling calculations.

Do migrating cells need a nucleus?

Science.gov (United States)

Hawkins, Rhoda J

2018-03-05

How the nucleus affects cell polarity and migration is unclear. In this issue, Graham et al. (2018. J. Cell Biol. https://doi.org/10.1083/jcb.201706097) show that enucleated cells polarize and migrate in two but not three dimensions and propose that the nucleus is a necessary component of the molecular clutch regulating normal mechanical responses. © 2018 Hawkins.

Study of high energy densities over extended nuclear volumes via nucleus-nucleus collisions at the SPS

CERN Multimedia

2002-01-01

This experiment examines in detail the characteristics of ultra-relativistic nucleus-nucleus interactions using $^{16}$O beams of 200 GeV/A from the SPS. The experiment combines 4$\\pi$ calorimeter coverage with measurements of inclusive particle spectra, two-particle correlations, low and high-mass lepton pairs and photons. A multiwire active target allows maximum interaction rates with a minimum of secondary interactions. Additional data are taken with an emulsion target.

International Halley Watch: Discipline specialists for near-nucleus studies

Science.gov (United States)

Larson, S.; Sekanina, Z.; Rahe, J.

1986-01-01

The purpose of the Near-Nucleus Studies Net is to study the processes taking place in the near-nucleus environment as they relate to the nature of nucleus. This is accomplisghed by measuring the spatial and temporal distribution of dust, gases and ions in the coma on high resolution images taken from many observatories around the world. By modeling the motions of discrete dust features in Comet Halley, it is often possible to determine the locations of the emission sources on the surface and learn about the nucleus structure. In addition to the general goals shared by all IHW nets, the scientific goals of the net has been to determine (1)the gross surface structure of the nucleus, (2)the nucleus spin vector, (3)the distribution and evolution of jet sources and (4)the interrelationships between the gas, dust and ion components of the coma. An additional Comet Giacobini-Zinner watch was carried out by the NNSN in support of the NASA International Cometary Explorer flyby.

Diabatic emission of neutrons: A probe for the energy dissipation mechanism in nucleus-nucleus collisions

International Nuclear Information System (INIS)

Noerenberg, W.; Cassing, W.

1984-05-01

The precompound emission of neutrons in central nucleus-nucleus collisions is investigated within the framework of dissipative diabatic dynamics. For 92 Mo + 92 Mo at bombarding energies between 7.5 and 20 MeV/u the differential neutron multiplicities dMsub(n)/dEsub(n) are estimated from the decay of highly excited diabatic single-particle states. The energy spectra have an almost exponential high-energy tail with effective temperatures up to 10 MeV for 20 MeV/u bombarding energy. (orig.)

Study of Strange and Multistrange Particles in Ultrarelativistic Nucleus-Nucleus Collisions

CERN Multimedia

Vande vyvre, P; Feofilov, G; Snoeys, W; Hetland, K F; Campbell, M; Klempt, W

2002-01-01

% NA57\\\\ \\\\ The goal of the experiment is to study the production of strange and multi-strange particles in nucleus-nucleus collisions. This study was initiated at the OMEGA spectrometer, where three ion experiments have been performed: WA85 (S-W and p-W collisions at 200 A GeV/c), WA94 (S-S and p-S collisions at 200 A GeV/c) and WA97 (Pb-Pb, p-Pb and p-Be collisions at 160 A GeV/c).\\\\ \\\\ The experiment aims at extending the scope of WA97 by:\\\\ \\\\ - investigating the beam energy dependence of the enhancements of multi-strange particle production reported by the previous experiments, and by\\\\ \\\\\\\\ \\\\- measuring the yields of strange and multi-strange particles over an extended centrality range compared with the previous experiments.\\\\ \\\\ The apparatus consists mainly of silicon pixel detector planes.

Decline in verbal fluency after subthalamic nucleus deep brain stimulation in Parkinson's disease: a microlesion effect of the electrode trajectory?

Science.gov (United States)

Le Goff, Floriane; Derrey, Stéphane; Lefaucheur, Romain; Borden, Alaina; Fetter, Damien; Jan, Maryvonne; Wallon, David; Maltête, David

2015-01-01

Decline in verbal fluency (VF) is frequently reported after chronic deep brain stimulation (DBS) of the subthalamic nucleus (STN) in Parkinson disease (PD). We investigated whether the trajectory of the implanted electrode correlate with the VF decline 6 months after surgery. We retrospectively analysed 59 PD patients (mean age, 61.9 ± 7; mean disease duration, 13 ± 4.6) who underwent bilateral STN-DBS. The percentage of VF decline 6 months after STN-DBS in the on-drug/on-stimulation condition was determined in respect of the preoperative on-drug condition. The patients were categorised into two groups (decline and stable) for each VF. Cortical entry angles, intersection with deep grey nuclei (caudate, thalamic or pallidum), and anatomical extent of the STN affected by the electrode pathway, were compared between groups. A significant decline of both semantic and phonemic VF was found after surgery, respectively 14.9% ± 22.1 (P < 0.05) and 14.2% ± 30.3 (P < 0.05). Patients who declined in semantic VF (n = 44) had a left trajectory with a more anterior cortical entry point (56 ± 53 versus 60 ± 55 degree, P = 0.01) passing less frequently trough the thalamus (P = 0.03). Microlesion of left brain regions may contribute to subtle cognitive impairment following STN-DBS in PD.

Bed Bug Infestations and Control Practices in China: Implications for Fighting the Global Bed Bug Resurgence

Directory of Open Access Journals (Sweden)

Changlu Wang

2011-04-01

Full Text Available The bed bug resurgence in North America, Europe, and Australia has elicited interest in investigating the causes of the widespread and increasing infestations and in developing more effective control strategies. In order to extend global perspectives on bed bug management, we reviewed bed bug literature in China by searching five Chinese language electronic databases. We also conducted telephone interviews of 68 pest control firms in two cities during March 2011. In addition, we conducted telephone interviews to 68 pest control companies within two cities in March 2011. Two species of bed bugs (Cimex lectularius L. and Cimex hemipterus (F. are known to occur in China. These were common urban pests before the early1980s. Nationwide “Four-Pest Elimination” campaigns (bed bugs being one of the targeted pests were implemented in China from 1960 to the early 1980s. These campaigns succeeded in the elimination of bed bug infestations in most communities. Commonly used bed bug control methods included applications of hot water, sealing of bed bug harborages, physical removal, and applications of residual insecticides (mainly organophosphate sprays or dusts. Although international and domestic travel has increased rapidly in China over the past decade (2000–2010, there have only been sporadic new infestations reported in recent years. During 1999–2009, all documented bed bug infestations were found in group living facilities (military dormitories, worker dormitories, and prisons, hotels, or trains. One city (Shenzhen city near Hong Kong experienced significantly higher number of bed bug infestations. This city is characterized by a high concentration of migratory factory workers. Current bed bug control practices include educating residents, washing, reducing clutter, putting items under the hot sun in summer, and applying insecticides (pyrethroids or organophosphates. There have not been any studies or reports on bed bug insecticide

Agglomeration of bed material: Influence on efficiency of biofuel fluidized bed boiler

Directory of Open Access Journals (Sweden)

Ryabov Georgy A.

2003-01-01

Full Text Available The successful design and operation of a fluidized bed combustor requires the ability to control and mitigate ash-related problems. The main ash-related problem of biomass filing boiler is agglomeration. The fluidized bed boiler with steam capacity of 66 t/h (4 MPa, 440 °C was started up at the Arkhangelsk Paper-Pi dp-Plant in 2001. This boiler was manufactured by the Russian companies "Energosofin" and "Belenergomash" and installed instead of the existing boiler with mechanical grate. Some constructional elements and steam drum of existing boiler remained unchanged. The primary air fan was installed past the common air fan, which supply part of the air into 24 secondary airports. First operating period shows that the bed material is expanded and then operator should increase the primary air rate, and the boiler efficiency dramatically decreases. Tills paper presents some results of our investigations of fuel, bed and fly ash chemical compositions and other characteristics. Special experiments were carried out to optimize the bed drain flow rate. The influence of secondly air supply improvement on mixing with the main flow and boiler efficiency are given.

Seaweed beds support more juvenile reef fish than seagrass beds in a south-western Atlantic tropical seascape

Science.gov (United States)

Eggertsen, L.; Ferreira, C. E. L.; Fontoura, L.; Kautsky, N.; Gullström, M.; Berkström, C.

2017-09-01

Seascape connectivity is regarded essential for healthy reef fish communities in tropical shallow systems. A number of reef fish species use separate adult and nursery habitats, and hence contribute to nutrient and energy transfer between habitats. Seagrass beds and mangroves often constitute important nursery habitats, with high structural complexity and protection from predation. Here, we investigated if reef fish assemblages in the tropical south-western Atlantic demonstrate ontogenetic habitat connectivity and identify possible nurseries on three reef systems along the eastern Brazilian coast. Fish were surveyed in fore reef, back reef, Halodule wrightii seagrass beds and seaweed beds. Seagrass beds contained lower abundances and species richness of fish than expected, while Sargassum-dominated seaweed beds contained significantly more juveniles than all other habitats (average juvenile fish densities: 32.6 per 40 m2 in Sargassum beds, 11.2 per 40 m2 in back reef, 10.1 per 40 m2 in fore reef, and 5.04 per 40 m2 in seagrass beds), including several species that are found in the reef habitats as adults. Species that in other regions worldwide (e.g. the Caribbean) utilise seagrass beds as nursery habitats were here instead observed in Sargassum beds or back reef habitats. Coral cover was not correlated to adult fish distribution patterns; instead, type of turf was an important variable. Connectivity, and thus pathways of nutrient transfer, seems to function differently in east Brazil compared to many tropical regions. Sargassum-dominated beds might be more important as nurseries for a larger number of fish species than seagrass beds. Due to the low abundance of structurally complex seagrass beds we suggest that seaweed beds might influence adult reef fish abundances, being essential for several keystone species of reef fish in the tropical south-western Atlantic.

Investigation of heat transfer in bed and freeboard of fluidized bed combustors

International Nuclear Information System (INIS)

Mitor, V.V.; Matsnev, V.V.; Sorokin, A.P.

1986-01-01

Experimental results for heat transfer between immersed bundles of bare tubes and fluidized beds are reported. The experimental results are obtained on industrial boilers with a bed area from 2,5 to 4 m/sup 2/ under conditions of long term operation. The bed temperature range has been 1073 0 K-1233 0 K, gas velocity between 1,8-4,5 m/s, mean particle size from 1,5 mm to 6,0 mm, freeboard furnace height of 2,3 and 5 m. The obtained data are compared with experimental results from literature

The picture of the nuclei disintegration mechanism - from nucleus-nucleus collision experimental data at high energies

International Nuclear Information System (INIS)

Strugalska-Gola, E.; Strugalski, Z.

1997-01-01

Experimental data on nuclear collisions at high energies, mainly obtained from photographic emulsions, are considered from the point of view of the picture of the nuclear collision processes mechanisms prompted experimentally. In fact, the disintegration products of each nucleus involved in a nuclear collision, in its own rest-frame, are similar to that produced by the impact of a number of nucleons of velocity equal to that of the moving primary nucleus