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Sample records for left lateral temporal

  1. Left or right? Lateralizing temporal lobe epilepsy by dynamic amygdala fMRI.

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    Ives-Deliperi, Victoria; Butler, James Thomas; Jokeit, Hennric

    2017-05-01

    In this case series, the findings of 85 functional MRI studies employing a dynamic fearful face paradigm are reported. Previous findings have shown the paradigm to generate bilateral amygdala activations in healthy subjects and unilateral activations in patients with MTLE, in the contralateral hemisphere to seizure origin. Such findings suggest ipsilateral limbic pathology and offer collateral evidence in lateralizing MTLE. The series includes 60 patients with TLE, 12 patients with extra-temporal lobe epilepsy, and 13 healthy controls. Functional MRI studies using a 1.5T scanner were conducted over a three-year period at a single epilepsy center and individual results were compared with EEG findings. In the cohort of unilateral TLE patients, lateralized activations of the amygdala were concordant with EEG findings in 76% of patients (77% lTLE, 74% rTLE). The differences in the mean lateralized indices of the lTLE, rTLE, and healthy control groups were all statistically significant. Lateralized amygdala activations were concordant with EEG findings in only 31% of the 12 patients with extra-temporal lobe epilepsy and bilateral amygdala activations were generated in all but one of the healthy control subjects. This case series further endorses the utility of the dynamic fearful face functional MRI paradigm using the widely available 1.5T as an adjunctive investigation to lateralize TLE. Copyright © 2017 Elsevier Inc. All rights reserved.

  2. Lateralization of spatial rather than temporal attention underlies the left hemifield advantage in rapid serial visual presentation.

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    Asanowicz, Dariusz; Kruse, Lena; Śmigasiewicz, Kamila; Verleger, Rolf

    2017-11-01

    In bilateral rapid serial visual presentation (RSVP), the second of two targets, T1 and T2, is better identified in the left visual field (LVF) than in the right visual field (RVF). This LVF advantage may reflect hemispheric asymmetry in temporal attention or/and in spatial orienting of attention. Participants performed two tasks: the "standard" bilateral RSVP task (Exp.1) and its unilateral variant (Exp.1 & 2). In the bilateral task, spatial location was uncertain, thus target identification involved stimulus-driven spatial orienting. In the unilateral task, the targets were presented block-wise in the LVF or RVF only, such that no spatial orienting was needed for target identification. Temporal attention was manipulated in both tasks by varying the T1-T2 lag. The results showed that the LVF advantage disappeared when involvement of stimulus-driven spatial orienting was eliminated, whereas the manipulation of temporal attention had no effect on the asymmetry. In conclusion, the results do not support the hypothesis of hemispheric asymmetry in temporal attention, and provide further evidence that the LVF advantage reflects right hemisphere predominance in stimulus-driven orienting of spatial attention. These conclusions fit evidence that temporal attention is implemented by bilateral parietal areas and spatial attention by the right-lateralized ventral frontoparietal network. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Spontaneous lateral temporal encephalocele.

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    Tuncbilek, Gokhan; Calis, Mert; Akalan, Nejat

    2013-01-01

    A spontaneous encephalocele is one that develops either because of embryological maldevelopment or from a poorly understood postnatal process that permits brain herniation to occur. We here report a rare case of lateral temporal encephalocele extending to the infratemporal fossa under the zygomatic arch. At birth, the infant was noted to have a large cystic mass in the right side of the face. After being operated on initially in another center in the newborn period, the patient was referred to our clinic with a diagnosis of temporal encephalocele. He was 6 months old at the time of admission. Computerized tomography scan and magnetic resonance imaging studies revealed a 8 × 9 cm fluid-filled, multiloculated cystic mass at the right infratemporal fossa. No intracranial pathology or connection is seen. The patient was operated on to reduce the distortion effect of the growing mass. The histopathological examination of the sac revealed well-differentiated mature glial tissue stained with glial fibrillary acid protein. This rare clinical presentation of encephaloceles should be taken into consideration during the evaluation of the lateral facial masses in the infancy period, and possible intracranial connection should be ruled out before surgery to avoid complications.

  4. Differential neuropsychological test sensitivity to left temporal lobe epilepsy.

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    Loring, David W; Strauss, Esther; Hermann, Bruce P; Barr, William B; Perrine, Kenneth; Trenerry, Max R; Chelune, Gordon; Westerveld, Michael; Lee, Gregory P; Meador, Kimford J; Bowden, Stephen C

    2008-05-01

    We examined the sensitivity of the Rey Auditory Verbal Learning Test (AVLT), California Verbal Learning Test (CVLT), Boston Naming Test (BNT), and Multilingual Aphasia Examination Visual Naming subtest (MAE VN) to lateralized temporal lobe epilepsy (TLE) in patients who subsequently underwent anterior temporal lobectomy. For the AVLT (n = 189), left TLE patients performed more poorly than their right TLE counterparts [left TLE = 42.9 (10.6), right TLE = 47.7 (9.9); p LTE = 40.7 (11.1), right TLE = 43.8 (9.9); (p measures of confrontation naming ability [BNT: left LTE = 43.1 (8.9), right TLE = 48.1 (8.9); p < .001 (Cohen's d = .56); MAE VN: left TLE = 42.2, right TLE = 45.6, p = .02 (Cohen's d = .36)]. When these data were modeled in independent logistic regression analyses, the AVLT and BNT both significantly predicted side of seizure focus, although the positive likelihood ratios were modest. In the subset of 108 patients receiving both BNT and AVLT, the AVLT was the only significant predictor of seizure laterality, suggesting individual patient variability regarding whether naming or memory testing may be more sensitive to lateralized TLE.

  5. Age-Dependent Mesial Temporal Lobe Lateralization in Language FMRI

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    Sepeta, Leigh N.; Berl, Madison M.; Wilke, Marko; You, Xiaozhen; Mehta, Meera; Xu, Benjamin; Inati, Sara; Dustin, Irene; Khan, Omar; Austermuehle, Alison; Theodore, William H.; Gaillard, William D.

    2015-01-01

    Objective FMRI activation of the mesial temporal lobe (MTL) may be important for epilepsy surgical planning. We examined MTL activation and lateralization during language fMRI in children and adults with focal epilepsy. Methods 142 controls and patients with left hemisphere focal epilepsy (Pediatric: epilepsy, n = 17, mean age = 9.9 ± 2.0; controls, n = 48; mean age = 9.1 ± 2.6; Adult: epilepsy, n = 20, mean age = 26.7 ± 5.8; controls, n = 57, mean age = 26.2 ± 7.5) underwent 3T fMRI using a language task (auditory description decision task). Image processing and analyses were conducted in SPM8; ROIs included MTL, Broca’s area, and Wernicke’s area. We assessed group and individual MTL activation, and examined degree of lateralization. Results Patients and controls (pediatric and adult) demonstrated group and individual MTL activation during language fMRI. MTL activation was left lateralized for adults but less so in children (p’s < 0.005). Patients did not differ from controls in either age group. Stronger left-lateralized MTL activation was related to older age (p = 0.02). Language lateralization (Broca’s and Wernicke’s) predicted 19% of the variance in MTL lateralization for adults (p = 0.001), but not children. Significance Language fMRI may be used to elicit group and individual MTL activation. The developmental difference in MTL lateralization and its association with language lateralization suggests a developmental shift in lateralization of MTL function, with increased left lateralization across the age span. This shift may help explain why children have better memory outcomes following resection compared to adults. PMID:26696589

  6. Left-handedness and language lateralization in children.

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    Szaflarski, Jerzy P; Rajagopal, Akila; Altaye, Mekibib; Byars, Anna W; Jacola, Lisa; Schmithorst, Vincent J; Schapiro, Mark B; Plante, Elena; Holland, Scott K

    2012-01-18

    This fMRI study investigated the development of language lateralization in left- and righthanded children between 5 and 18 years of age. Twenty-seven left-handed children (17 boys, 10 girls) and 54 age- and gender-matched right-handed children were included. We used functional MRI at 3T and a verb generation task to measure hemispheric language dominance based on either frontal or temporo-parietal regions of interest (ROIs) defined for the entire group and applied on an individual basis. Based on the frontal ROI, in the left-handed group, 23 participants (85%) demonstrated left-hemispheric language lateralization, 3 (11%) demonstrated symmetric activation, and 1 (4%) demonstrated right-hemispheric lateralization. In contrast, 50 (93%) of the right-handed children showed left-hemispheric lateralization and 3 (6%) demonstrated a symmetric activation pattern, while one (2%) demonstrated a right-hemispheric lateralization. The corresponding values for the temporo-parietal ROI for the left-handed children were 18 (67%) left-dominant, 6 (22%) symmetric, 3 (11%) right-dominant and for the right-handed children 49 (91%), 4 (7%), 1 (2%), respectively. Left-hemispheric language lateralization increased with age in both groups but somewhat different lateralization trajectories were observed in girls when compared to boys. The incidence of atypical language lateralization in left-handed children in this study was similar to that reported in adults. We also found similar rates of increase in left-hemispheric language lateralization with age between groups (i.e., independent of handedness) indicating the presence of similar mechanisms for language lateralization in left- and right-handed children. Copyright © 2011 Elsevier B.V. All rights reserved.

  7. Lateralization for dynamic facial expressions in human superior temporal sulcus.

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    De Winter, François-Laurent; Zhu, Qi; Van den Stock, Jan; Nelissen, Koen; Peeters, Ronald; de Gelder, Beatrice; Vanduffel, Wim; Vandenbulcke, Mathieu

    2015-02-01

    Most face processing studies in humans show stronger activation in the right compared to the left hemisphere. Evidence is largely based on studies with static stimuli focusing on the fusiform face area (FFA). Hence, the pattern of lateralization for dynamic faces is less clear. Furthermore, it is unclear whether this property is common to human and non-human primates due to predisposing processing strategies in the right hemisphere or that alternatively left sided specialization for language in humans could be the driving force behind this phenomenon. We aimed to address both issues by studying lateralization for dynamic facial expressions in monkeys and humans. Therefore, we conducted an event-related fMRI experiment in three macaques and twenty right handed humans. We presented human and monkey dynamic facial expressions (chewing and fear) as well as scrambled versions to both species. We studied lateralization in independently defined face-responsive and face-selective regions by calculating a weighted lateralization index (LIwm) using a bootstrapping method. In order to examine if lateralization in humans is related to language, we performed a separate fMRI experiment in ten human volunteers including a 'speech' expression (one syllable non-word) and its scrambled version. Both within face-responsive and selective regions, we found consistent lateralization for dynamic faces (chewing and fear) versus scrambled versions in the right human posterior superior temporal sulcus (pSTS), but not in FFA nor in ventral temporal cortex. Conversely, in monkeys no consistent pattern of lateralization for dynamic facial expressions was observed. Finally, LIwms based on the contrast between different types of dynamic facial expressions (relative to scrambled versions) revealed left-sided lateralization in human pSTS for speech-related expressions compared to chewing and emotional expressions. To conclude, we found consistent laterality effects in human posterior STS but not

  8. Autobiographical memory in temporal lobe epilepsy: role of hippocampal and temporal lateral structures.

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    Herfurth, Kirsten; Kasper, Burkhard; Schwarz, Michael; Stefan, Hermann; Pauli, Elisabeth

    2010-11-01

    The present study was aimed at investigating the impact of hippocampal and temporal cortical lesions on remote autobiographical memories in temporal lobe epilepsy (TLE). Episodic specificity, episodic richness, and personal semantic memory from different life periods were assessed using a modified version of the Autobiographical Memory Interview (AMI) (M.D. Kopelman, A.E. Wilson, A. Baddeley, The autobiographical memory interview. Bury St. Edmunds: Thames Valley Test Co.; 1990) in 47 patients with unilateral mesial or lateral TLE and 38 healthy controls. Patients with TLE performed significantly more poorly than controls. Patients with left and right mTLE were equally moderately impaired, but patients with left lateral TLE had the most severe episodic memory deficits, particularly for childhood memories. With respect to personal semantic memory, patients with left TLE were significantly more impaired than those with right TLE, most pronounced for childhood memories. Both autobiographical memory aspects, episodic and personal semantic memory, were significantly intercorrelated, but both did not correlate with anterograde memory, indicating a structural dissociation between both functions. Copyright © 2010 Elsevier Inc. All rights reserved.

  9. Task-dependent modulation of regions in the left temporal cortex during auditory sentence comprehension.

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    Zhang, Linjun; Yue, Qiuhai; Zhang, Yang; Shu, Hua; Li, Ping

    2015-01-01

    Numerous studies have revealed the essential role of the left lateral temporal cortex in auditory sentence comprehension along with evidence of the functional specialization of the anterior and posterior temporal sub-areas. However, it is unclear whether task demands (e.g., active vs. passive listening) modulate the functional specificity of these sub-areas. In the present functional magnetic resonance imaging (fMRI) study, we addressed this issue by applying both independent component analysis (ICA) and general linear model (GLM) methods. Consistent with previous studies, intelligible sentences elicited greater activity in the left lateral temporal cortex relative to unintelligible sentences. Moreover, responses to intelligibility in the sub-regions were differentially modulated by task demands. While the overall activation patterns of the anterior and posterior superior temporal sulcus and middle temporal gyrus (STS/MTG) were equivalent during both passive and active tasks, a middle portion of the STS/MTG was found to be selectively activated only during the active task under a refined analysis of sub-regional contributions. Our results not only confirm the critical role of the left lateral temporal cortex in auditory sentence comprehension but further demonstrate that task demands modulate functional specialization of the anterior-middle-posterior temporal sub-areas. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  10. Correlation of vocals and lyrics with left temporal musicogenic epilepsy.

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    Tseng, Wei-En J; Lim, Siew-Na; Chen, Lu-An; Jou, Shuo-Bin; Hsieh, Hsiang-Yao; Cheng, Mei-Yun; Chang, Chun-Wei; Li, Han-Tao; Chiang, Hsing-I; Wu, Tony

    2018-03-15

    Whether the cognitive processing of music and speech relies on shared or distinct neuronal mechanisms remains unclear. Music and language processing in the brain are right and left temporal functions, respectively. We studied patients with musicogenic epilepsy (ME) that was specifically triggered by popular songs to analyze brain hyperexcitability triggered by specific stimuli. The study included two men and one woman (all right-handed, aged 35-55 years). The patients had sound-triggered left temporal ME in response to popular songs with vocals, but not to instrumental, classical, or nonvocal piano solo versions of the same song. Sentimental lyrics, high-pitched singing, specificity/familiarity, and singing in the native language were the most significant triggering factors. We found that recognition of the human voice and analysis of lyrics are important causal factors in left temporal ME and provide observational evidence that sounds with speech structure are predominantly processed in the left temporal lobe. A literature review indicated that language-associated stimuli triggered ME in the left temporal epileptogenic zone at a nearly twofold higher rate compared with the right temporal region. Further research on ME may enhance understanding of the cognitive neuroscience of music. © 2018 New York Academy of Sciences.

  11. Ictal spitting in left temporal lobe epilepsy: report of three cases.

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    Caboclo, Luís Otávio Sales Ferreira; Miyashira, Flavia Saori; Hamad, Ana Paula Andrade; Lin, Katia; Carrete, Henrique; Sakamoto, Américo Ceiki; Yacubian, Elza Márcia Targas

    2006-09-01

    Ictal spitting is rarely reported in patients with epilepsy. More often it is observed in patients with temporal lobe epilepsy (TLE) and is presumed to be a lateralizing sign to language nondominant hemisphere. We report three patients with left TLE who had ictal spitting registered during prolonged video-EEG monitoring. Medical charts of all patients with medically refractory partial epilepsy submitted to prolonged video-EEG monitoring in the Epilepsy Unit at UNIFESP during a 3-year period were reviewed, in search of reports of ictal spitting. The clinical, neurophysiological and neuroimaging data of the identified patients were reviewed. Among 136 patients evaluated with prolonged video-EEG monitoring, three (2.2%) presented spitting automatisms during complex partial seizures. All of them were right-handed, and had clear signs of left hippocampal sclerosis on MRI. In two patients, in all seizures in which ictal spitting was observed, EEG seizure onset was seen in the left temporal lobe. In the third patient, ictal onset with scalp electrodes was observed in the right temporal lobe, but semi-invasive monitoring with foramen ovale electrodes revealed ictal onset in the left temporal lobe, confirming false lateralization in surface records. The three patients became seizure-free following left anterior temporal lobectomy. Ictal spitting is a rare finding in patients with epilepsy, and may be considered a localizing sign of seizure onset in the temporal lobe. It may be observed in seizures originating from the left temporal lobe, and thus should not be considered a lateralizing sign of nondominant TLE.

  12. Temporal order processing of syllables in the left parietal lobe.

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    Moser, Dana; Baker, Julie M; Sanchez, Carmen E; Rorden, Chris; Fridriksson, Julius

    2009-10-07

    Speech processing requires the temporal parsing of syllable order. Individuals suffering from posterior left hemisphere brain injury often exhibit temporal processing deficits as well as language deficits. Although the right posterior inferior parietal lobe has been implicated in temporal order judgments (TOJs) of visual information, there is limited evidence to support the role of the left inferior parietal lobe (IPL) in processing syllable order. The purpose of this study was to examine whether the left inferior parietal lobe is recruited during temporal order judgments of speech stimuli. Functional magnetic resonance imaging data were collected on 14 normal participants while they completed the following forced-choice tasks: (1) syllable order of multisyllabic pseudowords, (2) syllable identification of single syllables, and (3) gender identification of both multisyllabic and monosyllabic speech stimuli. Results revealed increased neural recruitment in the left inferior parietal lobe when participants made judgments about syllable order compared with both syllable identification and gender identification. These findings suggest that the left inferior parietal lobe plays an important role in processing syllable order and support the hypothesized role of this region as an interface between auditory speech and the articulatory code. Furthermore, a breakdown in this interface may explain some components of the speech deficits observed after posterior damage to the left hemisphere.

  13. Bilateral generic working memory circuit requires left-lateralized addition for verbal processing.

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    Ray, Manaan Kar; Mackay, Clare E; Harmer, Catherine J; Crow, Timothy J

    2008-06-01

    According to the Baddeley-Hitch model, phonological and visuospatial representations are separable components of working memory (WM) linked by a central executive. The traditional view that the separation reflects the relative contribution of the 2 hemispheres (verbal WM--left; spatial WM--right) has been challenged by the position that a common bilateral frontoparietal network subserves both domains. Here, we test the hypothesis that there is a generic WM circuit that recruits additional specialized regions for verbal and spatial processing. We designed a functional magnetic resonance imaging paradigm to elicit activation in the WM circuit for verbal and spatial information using identical stimuli and applied this in 33 healthy controls. We detected left-lateralized quantitative differences in the left frontal and temporal lobe for verbal > spatial WM but no areas of activation for spatial > verbal WM. We speculate that spatial WM is analogous to a "generic" bilateral frontoparietal WM circuit we inherited from our great ape ancestors that evolved, by recruitment of additional left-lateralized frontal and temporal regions, to accommodate language.

  14. Spatial memory for asymmetrical dot locations predicts lateralization among patients with presurgical mesial temporal lobe epilepsy.

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    Brown, Franklin C; Hirsch, Lawrence J; Spencer, Dennis D

    2015-11-01

    This study examined the ability of an asymmetrical dot location memory test (Brown Location Test, BLT) and two verbal memory tests (Verbal Selective Reminding Test (VSRT) and California Verbal Learning Test, Second Edition (CVLT-II)) to correctly lateralize left (LTLE) or right (RTLE) mesial temporal lobe epilepsy that was confirmed with video-EEG. Subjects consisted of 16 patients with medically refractory RTLE and 13 patients with medically refractory LTLE who were left hemisphere language dominant. Positive predictive values for lateralizing TLE correctly were 87.5% for the BLT, 72.7% for the VSRT, and 80% for the CVLT-II. Binary logistic regression indicated that the BLT alone correctly classified 76.9% of patients with left temporal lobe epilepsy and 87.5% of patients with right temporal lobe epilepsy. Inclusion of the verbal memory tests improved this to 92.3% of patients with left temporal lobe epilepsy and 100% correct classification of patients with right temporal lobe epilepsy. Though of a limited sample size, this study suggests that the BLT alone provides strong laterality information which improves with the addition of verbal memory tests. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Differences in graph theory functional connectivity in left and right temporal lobe epilepsy.

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    Chiang, Sharon; Stern, John M; Engel, Jerome; Levin, Harvey S; Haneef, Zulfi

    2014-12-01

    To investigate lateralized differences in limbic system functional connectivity between left and right temporal lobe epilepsy (TLE) using graph theory. Interictal resting state fMRI was performed in 14 left TLE patients, 11 right TLE patients, and 12 controls. Graph theory analysis of 10 bilateral limbic regions of interest was conducted. Changes in edgewise functional connectivity, network topology, and regional topology were quantified, and then left and right TLE were compared. Limbic edgewise functional connectivity was predominantly reduced in both left and right TLE. More regional connections were reduced in right TLE, most prominently involving reduced interhemispheric connectivity between the bilateral insula and bilateral hippocampi. A smaller number of limbic connections were increased in TLE, more so in left than in right TLE. Topologically, the most pronounced change was a reduction in average network betweenness centrality and concurrent increase in left hippocampal betweenness centrality in right TLE. In contrast, left TLE exhibited a weak trend toward increased right hippocampal betweenness centrality, with no change in average network betweenness centrality. Limbic functional connectivity is predominantly reduced in both left and right TLE, with more pronounced reductions in right TLE. In contrast, left TLE exhibits both edgewise and topological changes that suggest a tendency toward reorganization. Network changes in TLE and lateralized differences thereof may have important diagnostic and prognostic implications. Published by Elsevier B.V.

  16. Orbitotomía lateral mediante abordaje temporal Lateral orbitotomy using a temporal approach

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    H. Herencia Nieto

    2005-12-01

    Full Text Available La orbitotomía lateral sigue siendo en el momento actual la técnica quirúrgica de elección para la biopsia o extirpación de lesiones intraorbitarias laterales al nervio óptico, la biopsia del propio nervio óptico y la extirpación de la glándula lacrimal. Se han descrito múltiples incisiones cutáneas para llevar a cabo esta intervención; la más frecuentemente empleada por el momento es la incisión palpebral, que discurre a nivel de alguna arruga del párpado superior. Aunque los resultados obtenidos con esta incisión suelen ser aceptables, no está exenta de complicaciones, ni estéticas ni funcionales. Por esto, en los últimos años han ido apareciendo nuevas incisiones que intentan evitar estas complicaciones. Entre estas nuevas vías de abordaje a la pared lateral de la órbita se encuentra la incisión temporal. En los últimos 3 años, se ha intervenido en nuestro servicio a cuatro pacientes para llevar a cabo biopsia o extirpación de masas intraorbitarias mediante orbitotomía lateral, siempre a través de una incisión temporal. En todos los casos esta incisión permitió una amplia exposición del campo quirúrgico y la cómoda realización de la intervención, obteniéndose resultados estéticos y funcionales excelentes, y sin ninguna secuela ni complicación permanente. La complicación específica más frecuente de esta incisión es la paresia de la rama frontal del nervio facial. Una técnica de disección cuidadosa suele ser suficiente para evitarla. Todo esto hace que esta incisión, tal y como la describimos aquí, sea de elección para llevar a cabo la orbitotomía lateral, constituyendo en nuestro criterio una alternativa perfectamente válida y a tener en cuenta frente a las incisiones «clásicas», a las que llega a superar en muchos aspectos.The lateral orbitotomy it still the surgical technique of choice for biopsies or the removal of intraorbital lesions that are lateral to the optic nerve, for biopsies of

  17. Functional connectivity between right and left mesial temporal structures.

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    Lacuey, Nuria; Zonjy, Bilal; Kahriman, Emine S; Kaffashi, Farhad; Miller, Jonathan; Lüders, Hans O

    2015-09-01

    The aim of this study is to investigate functional connectivity between right and left mesial temporal structures using cerebrocerebral evoked potentials. We studied seven patients with drug-resistant focal epilepsy who were explored with stereotactically implanted depth electrodes in bilateral hippocampi. In all patients cerebrocerebral evoked potentials evoked by stimulation of the fornix were evaluated as part of a research project assessing fornix stimulation for control of hippocampal seizures. Stimulation of the fornix elicited responses in the ipsilateral hippocampus in all patients with a mean latency of 4.6 ms (range 2-7 ms). Two patients (29 %) also had contralateral hippocampus responses with a mean latency of 7.5 ms (range 5-12 ms) and without involvement of the contralateral temporal neocortex or amygdala. This study confirms the existence of connections between bilateral mesial temporal structures in some patients and explains seizure discharge spreading between homotopic mesial temporal structures without neocortical involvement.

  18. Lateral head turning affects temporal memory.

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    Vicario, Carmelo Mario; Martino, Davide; Pavone, Enea Francesco; Fuggetta, Giorgio

    2011-08-01

    Spatial attention is a key factor in the exploration and processing of the surrounding environment, and plays a role in linking magnitudes such as space, time, and numbers. The present work evaluates whether shifting the coordinates of spatial attention through rotational head movements may affect the ability to estimate the duration of different time intervals. A computer-based implicit timing task was employed, in which participants were asked to concentrate and report verbally on colour changes of sequential stimuli displayed on a computer screen; subsequently, they were required to reproduce the temporal duration (ranging between 5 and 80 sec.) of the perceived stimuli using the computer keyboard. There was statistically significant overestimation of the 80-sec. intervals exclusively on the rightward rotation head posture, whereas head posture did not affect timing performances on shorter intervals. These findings support the hypothesis that the coordinates of spatial attention influence the ability to process time, consistent with the existence of common cortical metrics of space and time in healthy humans.

  19. Multisensory speech perception without the left superior temporal sulcus.

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    Baum, Sarah H; Martin, Randi C; Hamilton, A Cris; Beauchamp, Michael S

    2012-09-01

    Converging evidence suggests that the left superior temporal sulcus (STS) is a critical site for multisensory integration of auditory and visual information during speech perception. We report a patient, SJ, who suffered a stroke that damaged the left tempo-parietal area, resulting in mild anomic aphasia. Structural MRI showed complete destruction of the left middle and posterior STS, as well as damage to adjacent areas in the temporal and parietal lobes. Surprisingly, SJ demonstrated preserved multisensory integration measured with two independent tests. First, she perceived the McGurk effect, an illusion that requires integration of auditory and visual speech. Second, her perception of morphed audiovisual speech with ambiguous auditory or visual information was significantly influenced by the opposing modality. To understand the neural basis for this preserved multisensory integration, blood-oxygen level dependent functional magnetic resonance imaging (BOLD fMRI) was used to examine brain responses to audiovisual speech in SJ and 23 healthy age-matched controls. In controls, bilateral STS activity was observed. In SJ, no activity was observed in the damaged left STS but in the right STS, more cortex was active in SJ than in any of the normal controls. Further, the amplitude of the BOLD response in right STS response to McGurk stimuli was significantly greater in SJ than in controls. The simplest explanation of these results is a reorganization of SJ's cortical language networks such that the right STS now subserves multisensory integration of speech. Copyright © 2012 Elsevier Inc. All rights reserved.

  20. Left fronto-temporal dynamics during agreement processing: evidence for feature-specific computations.

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    Molinaro, Nicola; Barber, Horacio A; Pérez, Alejandro; Parkkonen, Lauri; Carreiras, Manuel

    2013-09-01

    Grammatical agreement is a widespread language phenomenon that indicates formal syntactic relations between words; however, it also conveys basic lexical (e.g. grammatical gender) or semantic (e.g. numerosity) information about a discourse referent. In this study, we focus on the reading of Spanish noun phrases, violating either number or gender determiner-noun agreement compared to grammatical controls. Magnetoencephalographic activity time-locked to the onset of the noun in both types of violation revealed a left-lateralized brain network involving anterior temporal regions (~220 ms) and, later in time, ventro-lateral prefrontal regions (>300 ms). These activations coexist with dependency-specific effects: in an initial step (~170 ms), occipito-temporal regions are employed for fine-grained analysis of the number marking (in Spanish, presence or absence of the suffix '-s'), while anterior temporal regions show increased activation for gender mismatches compared to grammatical controls. The semantic relevance of number agreement dependencies was mainly reflected by left superior temporal increased activity around 340 ms. These findings offer a detailed perspective on the multi-level analyses involved in the initial computation of agreement dependencies, and theoretically support a derivational approach to agreement computation. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. LAPAROSCOPIC LEFT LATERAL SECTIONECTOMY IN LIVING LIVER DONOR

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    S. V. Gautier

    2016-01-01

    Full Text Available Introduction. Living donor liver transplantation has proved to be an effective, safe and radical treatment modality for patients with end-stage liver diseases. Left lateral section (LLS of donor’s liver is used in pediatric recipients. Laparoscopic LLS procurement was fi rst described by D. Cherqui in 2002. At present, this technique is routinely used only by 5 hospitals in the world. However, up to date, some authors consider it to be a new standard to perform such a surgery in living donors.Aim. To analyze the fi rst Russian experience in laparoscopic left lateral sectionectomy (LapLLS in living related donor.Materials and methods. From May to September 2016 fi ve LapLLS were performed in living donors. In all cases donors were women (mothers in 4 cases and aunt in 1 case. Recipients were children aged from 6 months through 3 years with body mass from 5.6 to 12.5 kg. Liver transection was carried out under conditions of maintained blood supply. Parenchymal transection was performed using a harmonic scalpel, bipolar coagulation and ultrasound dissection.Results. Average donor age was 32 ± 5 years. Average operation time was 287 ± 16 min. Average LLS graft weight was 220 ± 16 g. Intraoperative blood loss did not exceed 100 ml (95 ± 5 ml. Donors were discharged on the 3rd–4th post-op day. There were no postoperative complications in donors. Recipients were also characterized by a standard course of the postoperative period.Conclusion. LapLLS is an effective and safe method with several advantages. Primarily, these are early rehabilitation of the donors and shortening of the hospital stay, which are important for the quick return to normal way of live. Excellent visualization of anatomical structures, including vascular and biliary ones, allows performing precise selection. In addition, good cosmetic effect is also an important aspect.

  2. Left hemisphere lateralization for lexical and acoustic pitch processing in Cantonese speakers as revealed by mismatch negativity.

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    Gu, Feng; Zhang, Caicai; Hu, Axu; Zhao, Guoping

    2013-12-01

    For nontonal language speakers, speech processing is lateralized to the left hemisphere and musical processing is lateralized to the right hemisphere (i.e., function-dependent brain asymmetry). On the other hand, acoustic temporal processing is lateralized to the left hemisphere and spectral/pitch processing is lateralized to the right hemisphere (i.e., acoustic-dependent brain asymmetry). In this study, we examine whether the hemispheric lateralization of lexical pitch and acoustic pitch processing in tonal language speakers is consistent with the patterns of function- and acoustic-dependent brain asymmetry in nontonal language speakers. Pitch contrast in both speech stimuli (syllable /ji/ in Experiment 1) and nonspeech stimuli (harmonic tone in Experiment 1; pure tone in Experiment 2) was presented to native Cantonese speakers in passive oddball paradigms. We found that the mismatch negativity (MMN) elicited by lexical pitch contrast was lateralized to the left hemisphere, which is consistent with the pattern of function-dependent brain asymmetry (i.e., left hemisphere lateralization for speech processing) in nontonal language speakers. However, the MMN elicited by acoustic pitch contrast was also left hemisphere lateralized (harmonic tone in Experiment 1) or showed a tendency for left hemisphere lateralization (pure tone in Experiment 2), which is inconsistent with the pattern of acoustic-dependent brain asymmetry (i.e., right hemisphere lateralization for acoustic pitch processing) in nontonal language speakers. The consistent pattern of function-dependent brain asymmetry and the inconsistent pattern of acoustic-dependent brain asymmetry between tonal and nontonal language speakers can be explained by the hypothesis that the acoustic-dependent brain asymmetry is the consequence of a carryover effect from function-dependent brain asymmetry. Potential evolutionary implication of this hypothesis is discussed. © 2013.

  3. Multimodal imaging of language reorganization in patients with left temporal lobe epilepsy.

    Science.gov (United States)

    Chang, Yu-Hsuan A; Kemmotsu, Nobuko; Leyden, Kelly M; Kucukboyaci, N Erkut; Iragui, Vicente J; Tecoma, Evelyn S; Kansal, Leena; Norman, Marc A; Compton, Rachelle; Ehrlich, Tobin J; Uttarwar, Vedang S; Reyes, Anny; Paul, Brianna M; McDonald, Carrie R

    2017-07-01

    This study explored the relationships among multimodal imaging, clinical features, and language impairment in patients with left temporal lobe epilepsy (LTLE). Fourteen patients with LTLE and 26 controls underwent structural MRI, functional MRI, diffusion tensor imaging, and neuropsychological language tasks. Laterality indices were calculated for each imaging modality and a principal component (PC) was derived from language measures. Correlations were performed among imaging measures, as well as to the language PC. In controls, better language performance was associated with stronger left-lateralized temporo-parietal and temporo-occipital activations. In LTLE, better language performance was associated with stronger right-lateralized inferior frontal, temporo-parietal, and temporo-occipital activations. These right-lateralized activations in LTLE were associated with right-lateralized arcuate fasciculus fractional anisotropy. These data suggest that interhemispheric language reorganization in LTLE is associated with alterations to perisylvian white matter. These concurrent structural and functional shifts from left to right may help to mitigate language impairment in LTLE. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Study on memories of temporal lobes and the principles of lateralization using near infrared spectroscopy

    Science.gov (United States)

    Kamakura, Katsutoshi

    2007-01-01

    In this study we measured the variation of brain blood quantity (Oxy-Hb, Deoxy-Hb and Total-Hb) in the temporal lobes using near infrared spectroscopy (NIRS) when the tasks of the memories were presented to the subjects. The memories are classified into the short-term memory (STM) and the long-term memory (LTM) including the episodic and semantic memories. The subjects joined in this study are 11 persons who are university students including graduate students. We used the language task of letter-number sequencing, also reverse sequencing to measure STM and the task of the episodic memory to measure LTM. As a result of analysis, concerning the episodic memory, the variation of Oxy-Hb in the left temporal lobe was larger than that of Oxy-Hb in the right temporal lobe. The result might suggest that the episodic memory has a relationship with cerebral dominance concerning language area in the left temporal lobe. It seems that the episodic memory meditated with the function of language used in this study is much stored in the left temporal lobe than in the right temporal lobe. This result coincides with the principles of lateralization. The variation of Oxy-Hb in the language task of letter-number sequencing was smaller than that of Oxy-Hb in the language task of the episodic memory.

  5. Task activation and functional connectivity show concordant memory laterality in temporal lobe epilepsy.

    Science.gov (United States)

    Sideman, Noah; Chaitanya, Ganne; He, Xiaosong; Doucet, Gaelle; Kim, Na Young; Sperling, Michael R; Sharan, Ashwini D; Tracy, Joseph I

    2018-04-01

    In epilepsy, asymmetries in the organization of mesial temporal lobe (MTL) functions help determine the cognitive risk associated with procedures such as anterior temporal lobectomy. Past studies have investigated the change/shift in a visual episodic memory laterality index (LI) in mesial temporal lobe structures through functional magnetic resonance imaging (fMRI) task activations. Here, we examine whether underlying task-related functional connectivity (FC) is concordant with such standard fMRI laterality measures. A total of 56 patients with temporal lobe epilepsy (TLE) (Left TLE [LTLE]: 31; Right TLE [RTLE]: 25) and 34 matched healthy controls (HC) underwent fMRI scanning during performance of a scene encoding task (SET). We assessed an activation-based LI of the hippocampal gyrus (HG) and parahippocampal gyrus (PHG) during the SET and its correspondence with task-related FC measures. Analyses involving the HG and PHG showed that the patients with LTLE had a consistently higher LI (right-lateralized) than that of the HC and group with RTLE, indicating functional reorganization. The patients with RTLE did not display a reliable contralateral shift away from the pathology, with the mesial structures showing quite distinct laterality patterns (HG, no laterality bias; PHG, no evidence of LI shift). The FC data for the group with LTLE provided confirmation of reorganization effects, revealing that a rightward task LI may be based on underlying connections between several left-sided regions (middle/superior occipital and left medial frontal gyri) and the right PHG. The FCs between the right HG and left anterior cingulate/medial frontal gyri were also observed in LTLE. Importantly, the data demonstrate that the areas involved in the LTLE task activation shift to the right hemisphere showed a corresponding increase in task-related FCs between the hemispheres. Altered laterality patterns based on mesial temporal lobe epilepsy (MTLE) pathology manifest as several

  6. Left preference for sport tasks does not necessarily indicate left-handedness: sport-specific lateral preferences, relationship with handedness and implications for laterality research in behavioural sciences.

    Directory of Open Access Journals (Sweden)

    Florian Loffing

    Full Text Available In the elite domain of interactive sports, athletes who demonstrate a left preference (e.g., holding a weapon with the left hand in fencing or boxing in a 'southpaw' stance seem overrepresented. Such excess indicates a performance advantage and was also interpreted as evidence in favour of frequency-dependent selection mechanisms to explain the maintenance of left-handedness in humans. To test for an overrepresentation, the incidence of athletes' lateral preferences is typically compared with an expected ratio of left- to right-handedness in the normal population. However, the normal population reference values did not always relate to the sport-specific tasks of interest, which may limit the validity of reports of an excess of 'left-oriented' athletes. Here we sought to determine lateral preferences for various sport-specific tasks (e.g., baseball batting, boxing in the normal population and to examine the relationship between these preferences and handedness. To this end, we asked 903 participants to indicate their lateral preferences for sport-specific and common tasks using a paper-based questionnaire. Lateral preferences varied considerably across the different sport tasks and we found high variation in the relationship between those preferences and handedness. In contrast to unimanual tasks (e.g., fencing or throwing, for bimanually controlled actions such as baseball batting, shooting in ice hockey or boxing the incidence of left preferences was considerably higher than expected from the proportion of left-handedness in the normal population and the relationship with handedness was relatively low. We conclude that (i task-specific reference values are mandatory for reliably testing for an excess of athletes with a left preference, (ii the term 'handedness' should be more cautiously used within the context of sport-related laterality research and (iii observation of lateral preferences in sports may be of limited suitability for the

  7. Left preference for sport tasks does not necessarily indicate left-handedness: sport-specific lateral preferences, relationship with handedness and implications for laterality research in behavioural sciences.

    Science.gov (United States)

    Loffing, Florian; Sölter, Florian; Hagemann, Norbert

    2014-01-01

    In the elite domain of interactive sports, athletes who demonstrate a left preference (e.g., holding a weapon with the left hand in fencing or boxing in a 'southpaw' stance) seem overrepresented. Such excess indicates a performance advantage and was also interpreted as evidence in favour of frequency-dependent selection mechanisms to explain the maintenance of left-handedness in humans. To test for an overrepresentation, the incidence of athletes' lateral preferences is typically compared with an expected ratio of left- to right-handedness in the normal population. However, the normal population reference values did not always relate to the sport-specific tasks of interest, which may limit the validity of reports of an excess of 'left-oriented' athletes. Here we sought to determine lateral preferences for various sport-specific tasks (e.g., baseball batting, boxing) in the normal population and to examine the relationship between these preferences and handedness. To this end, we asked 903 participants to indicate their lateral preferences for sport-specific and common tasks using a paper-based questionnaire. Lateral preferences varied considerably across the different sport tasks and we found high variation in the relationship between those preferences and handedness. In contrast to unimanual tasks (e.g., fencing or throwing), for bimanually controlled actions such as baseball batting, shooting in ice hockey or boxing the incidence of left preferences was considerably higher than expected from the proportion of left-handedness in the normal population and the relationship with handedness was relatively low. We conclude that (i) task-specific reference values are mandatory for reliably testing for an excess of athletes with a left preference, (ii) the term 'handedness' should be more cautiously used within the context of sport-related laterality research and (iii) observation of lateral preferences in sports may be of limited suitability for the verification of

  8. Left Preference for Sport Tasks Does Not Necessarily Indicate Left-Handedness: Sport-Specific Lateral Preferences, Relationship with Handedness and Implications for Laterality Research in Behavioural Sciences

    Science.gov (United States)

    Loffing, Florian; Sölter, Florian; Hagemann, Norbert

    2014-01-01

    In the elite domain of interactive sports, athletes who demonstrate a left preference (e.g., holding a weapon with the left hand in fencing or boxing in a ‘southpaw’ stance) seem overrepresented. Such excess indicates a performance advantage and was also interpreted as evidence in favour of frequency-dependent selection mechanisms to explain the maintenance of left-handedness in humans. To test for an overrepresentation, the incidence of athletes' lateral preferences is typically compared with an expected ratio of left- to right-handedness in the normal population. However, the normal population reference values did not always relate to the sport-specific tasks of interest, which may limit the validity of reports of an excess of ‘left-oriented’ athletes. Here we sought to determine lateral preferences for various sport-specific tasks (e.g., baseball batting, boxing) in the normal population and to examine the relationship between these preferences and handedness. To this end, we asked 903 participants to indicate their lateral preferences for sport-specific and common tasks using a paper-based questionnaire. Lateral preferences varied considerably across the different sport tasks and we found high variation in the relationship between those preferences and handedness. In contrast to unimanual tasks (e.g., fencing or throwing), for bimanually controlled actions such as baseball batting, shooting in ice hockey or boxing the incidence of left preferences was considerably higher than expected from the proportion of left-handedness in the normal population and the relationship with handedness was relatively low. We conclude that (i) task-specific reference values are mandatory for reliably testing for an excess of athletes with a left preference, (ii) the term ‘handedness’ should be more cautiously used within the context of sport-related laterality research and (iii) observation of lateral preferences in sports may be of limited suitability for the

  9. Temporal reliability and lateralization of the resting-state language network.

    Science.gov (United States)

    Zhu, Linlin; Fan, Yang; Zou, Qihong; Wang, Jue; Gao, Jia-Hong; Niu, Zhendong

    2014-01-01

    The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.

  10. Temporal reliability and lateralization of the resting-state language network.

    Directory of Open Access Journals (Sweden)

    Linlin Zhu

    Full Text Available The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability.

  11. Temporal Reliability and Lateralization of the Resting-State Language Network

    Science.gov (United States)

    Zou, Qihong; Wang, Jue; Gao, Jia-Hong; Niu, Zhendong

    2014-01-01

    The neural processing loop of language is complex but highly associated with Broca's and Wernicke's areas. The left dominance of these two areas was the earliest observation of brain asymmetry. It was demonstrated that the language network and its functional asymmetry during resting state were reproducible across institutions. However, the temporal reliability of resting-state language network and its functional asymmetry are still short of knowledge. In this study, we established a seed-based resting-state functional connectivity analysis of language network with seed regions located at Broca's and Wernicke's areas, and investigated temporal reliability of language network and its functional asymmetry. The language network was found to be temporally reliable in both short- and long-term. In the aspect of functional asymmetry, the Broca's area was found to be left lateralized, while the Wernicke's area is mainly right lateralized. Functional asymmetry of these two areas revealed high short- and long-term reliability as well. In addition, the impact of global signal regression (GSR) on reliability of the resting-state language network was investigated, and our results demonstrated that GSR had negligible effect on the temporal reliability of the resting-state language network. Our study provided methodology basis for future cross-culture and clinical researches of resting-state language network and suggested priority of adopting seed-based functional connectivity for its high reliability. PMID:24475058

  12. Right away: A late, right-lateralized category effect complements an early, left-lateralized category effect in visual search.

    Science.gov (United States)

    Constable, Merryn D; Becker, Stefanie I

    2017-10-01

    According to the Sapir-Whorf hypothesis, learned semantic categories can influence early perceptual processes. A central finding in support of this view is the lateralized category effect-namely, the finding that categorically different colors (e.g., blue and green hues) can be discriminated faster than colors within the same color category (e.g., different hues of green), especially when they are presented in the right visual field. Because the right visual field projects to the left hemisphere, this finding has been popularly couched in terms of the left-lateralization of language. However, other studies have reported bilateral category effects, which has led some researchers to question the linguistic origins of the effect. Here we examined the time course of lateralized and bilateral category effects in the classical visual search paradigm by means of eyetracking and RT distribution analyses. Our results show a bilateral category effect in the manual responses, which is combined of an early, left-lateralized category effect and a later, right-lateralized category effect. The newly discovered late, right-lateralized category effect occurred only when observers had difficulty locating the target, indicating a specialization of the right hemisphere to find categorically different targets after an initial error. The finding that early and late stages of visual search show different lateralized category effects can explain a wide range of previously discrepant findings.

  13. How Auditory Experience Differentially Influences the Function of Left and Right Superior Temporal Cortices.

    Science.gov (United States)

    Twomey, Tae; Waters, Dafydd; Price, Cathy J; Evans, Samuel; MacSweeney, Mairéad

    2017-09-27

    To investigate how hearing status, sign language experience, and task demands influence functional responses in the human superior temporal cortices (STC) we collected fMRI data from deaf and hearing participants (male and female), who either acquired sign language early or late in life. Our stimuli in all tasks were pictures of objects. We varied the linguistic and visuospatial processing demands in three different tasks that involved decisions about (1) the sublexical (phonological) structure of the British Sign Language (BSL) signs for the objects, (2) the semantic category of the objects, and (3) the physical features of the objects.Neuroimaging data revealed that in participants who were deaf from birth, STC showed increased activation during visual processing tasks. Importantly, this differed across hemispheres. Right STC was consistently activated regardless of the task whereas left STC was sensitive to task demands. Significant activation was detected in the left STC only for the BSL phonological task. This task, we argue, placed greater demands on visuospatial processing than the other two tasks. In hearing signers, enhanced activation was absent in both left and right STC during all three tasks. Lateralization analyses demonstrated that the effect of deafness was more task-dependent in the left than the right STC whereas it was more task-independent in the right than the left STC. These findings indicate how the absence of auditory input from birth leads to dissociable and altered functions of left and right STC in deaf participants. SIGNIFICANCE STATEMENT Those born deaf can offer unique insights into neuroplasticity, in particular in regions of superior temporal cortex (STC) that primarily respond to auditory input in hearing people. Here we demonstrate that in those deaf from birth the left and the right STC have altered and dissociable functions. The right STC was activated regardless of demands on visual processing. In contrast, the left STC was

  14. Socintigraphic evaluation of lateral segment of the left lobe of the liver

    International Nuclear Information System (INIS)

    Oyama, Kazuyuki; Hayashi, Sanshin; Kogure, Takashi; Hirakawa, Ken; Akaike, Akira

    1979-01-01

    Lateral segment of left lobe of the liver is clearly demarcated on sup(99m) Tc-labeled cholescintigram. With analysis of 112 sup(99m) Tc-pyridoxylideneisoleucine scintigrams about lateral border of left lobe, there are some variants in 22 cases (19.7%) in shape in lateral segment of Type 4 left lobe in morphologic classification. Of lateral segment of left lobe, there are classified into five types in the anterior view according to the degeneration; Type 1 is gradually elongated tapered type in 8 cases (36.4%), Type 2 is laterally elongated type as rod shape or island shape in 5 cases (22.7%), Type 3 is lobulated type in 1 case (4.6%), Type 4 is narrowing type in 5 cases (22.7%), Type 5 is indentation type in 3 cases (13.6%). Using colloidal radiopharmaceuticals in liver scintigraphy, lateral segment of left lobe often overlapps with the spleen, which disturb to interpret the abnormality in left lobe of the liver and in the spleen. This analysis depends upon the recent advances in sup(99m) Tc-labeled hepatobiliary radiopharmaceuticals and equipment, and there has never discussed about the shape of lateral segment of left lobe in roentgenologic and scintigraphic evaluations. (author)

  15. Comparative Lateralizing Ability of Multimodality MRI in Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Karabekir Ercan

    2016-01-01

    Full Text Available Purpose. The objective is to compare lateralizing ability of three quantitative MR (qMRI modalities to depict changes of hippocampal architecture with clinical entities in temporal lobe epilepsy. Methods. We evaluated 14 patients with clinical and EEG proven diagnosis of unilateral TLE and 15 healthy volunteers. T1-weighted 3D dataset for volumetry, single-voxel 1H MR spectroscopy (MRS, and diffusion tensor imaging (DTI were performed for bilateral hippocampi of all subjects. Results. Individual volumetric measurements provided accurate lateralization in 85% of the patients, spectroscopy in 57%, and DTI in 57%. Higher lateralization ratios were acquired combining volumetry-spectroscopy (85%, spectroscopy-DTI (85%, and volumetry-DTI (100%. Significantly decreased NAA/(Cho+Cr ratios (p=0.002 and increased FA (p=0.001 values were obtained in ipsilateral to epileptogenic hippocampus. Duration of epilepsy and FA values showed a significant negative correlation (p=0.016, r=-0.847. The history of febrile convulsion associated with ipsilateral increased ADC values (p=0.015, r=0.851 and reduced NAA/(Cho+Cr ratios (p=0.047, r=-761. Conclusion. Volumetry, MRS, and DTI studies provide complementary information of hippocampal pathology. For lateralization of epileptogenic focus and preoperative examination, volumetry-DTI combination may be indicative of diagnostic accuracy.

  16. Asymmetry of medial and lateral temporal regional glucose metabolism in temporal lobe epilepsy by F-18-FDG PET

    International Nuclear Information System (INIS)

    Lee, Dong Soo; Yeo, Jeong Seok; Song, Ho Cheon; Lee, Sang Kun; Kim, Hyun Jip; Chung, June Key; Lee, Myung Chul

    1999-01-01

    We investigated the difference of glucose metabolism of medial and lateral temporal lobes of patients with temporal lobe epilepsy (TLE) utilizing quantitative comparison of regional metabolic activities using asymmetric index. We studied 19 pathologically proven mesial TLE and 25 lateral TLE patients. Lateral TLE patients were either normal on magnetic resonance imaging (cryptogenic: n=14) or had structural lesions (lesional: n=11). Asymmetric index (ASI) was calculated as [(ipsilateral contralateral)/(ipsilateral + contralateral )]x200. ASI of medial and lateral lobes of mesial TLE was decreased (-16.4±8.3 and -12.7± 5.5, respectively). In cryptogenic lateral TLE, ASI of lateral temporal lobe was decreased (-11.8± 4.7), whereas that of medial temporal lobe was not decreased (-4.6±6.3). ASI of medial lobe of lesional lateral TLE was -7.3±9.1, which was significantly different from that of mesial TLE (p<0.05). Patients with lesional lateral TLE had evident metabolic defects or decrease (ASI: -22±10.5) in lateral temporal lobe. While we could not find the difference of metabolic activity in lateral temporal lobes between cryptogenic lateral TLE and mesial TLE patients, the difference of metabolic activity was significant in medial temporal lobes which was revealed by ASI quantitation. Asymmetric decrease of metabolic activity in both medial and lateral temporal lobes indicates medial temporal epilepsy. Symmetry of metabolic activity in medial temporal lobe combined with asymmetry of that in lateral temporal lobe may give hints that the epileptogenic zone is lateral

  17. Temporal Lobe White Matter Asymmetry and Language Laterality in Epilepsy Patients

    Science.gov (United States)

    Ellmore, Timothy M.; Beauchamp, Michael S.; Breier, Joshua I.; Slater, Jeremy D.; Kalamangalam, Giridhar P.; O’Neill, Thomas J.; Disano, Michael A.; Tandon, Nitin

    2009-01-01

    Recent studies using diffusion tensor imaging (DTI) have advanced our knowledge of the organization of white matter subserving language function. It remains unclear, however, how DTI may be used to predict accurately a key feature of language organization: its asymmetric representation in one cerebral hemisphere. In this study of epilepsy patients with unambiguous lateralization on Wada testing (19 left and 4 right lateralized subjects; no bilateral subjects), the predictive value of DTI for classifying the dominant hemisphere for language was assessed relative to the existing standard - the intra-carotid Amytal (Wada) procedure. Our specific hypothesis is that language laterality in both unilateral left- and right-hemisphere language dominant subjects may be predicted by hemispheric asymmetry in the relative density of three white matter pathways terminating in the temporal lobe implicated in different aspects of language function: the arcuate (AF), uncinate (UF), and inferior longitudinal fasciculi (ILF). Laterality indices computed from asymmetry of high anisotropy AF pathways, but not the other pathways, classified the majority (19 of 23) of patients using the Wada results as the standard. A logistic regression model incorporating information from DTI of the AF, fMRI activity in Broca’s area, and handedness was able to classify 22 of 23 (95.6%) patients correctly according to their Wada score. We conclude that evaluation of highly anisotropic components of the AF alone has significant predictive power for determining language laterality, and that this markedly asymmetric distribution in the dominant hemisphere may reflect enhanced connectivity between frontal and temporal sites to support fluent language processes. Given the small sample reported in this preliminary study, future research should assess this method on a larger group of patients, including subjects with bihemispheric dominance. PMID:19874899

  18. Subliminal semantic priming changes the dynamic causal influence between the left frontal and temporal cortex.

    Science.gov (United States)

    Matsumoto, Atsushi; Kakigi, Ryusuke

    2014-01-01

    Recent neuroimaging experiments have revealed that subliminal priming of a target stimulus leads to the reduction of neural activity in specific regions concerned with processing the target. Such findings lead to questions about the degree to which the subliminal priming effect is based only on decreased activity in specific local brain regions, as opposed to the influence of neural mechanisms that regulate communication between brain regions. To address this question, this study recorded EEG during performance of a subliminal semantic priming task. We adopted an information-based approach that used independent component analysis and multivariate autoregressive modeling. Results indicated that subliminal semantic priming caused significant modulation of alpha band activity in the left inferior frontal cortex and modulation of gamma band activity in the left inferior temporal regions. The multivariate autoregressive approach confirmed significant increases in information flow from the inferior frontal cortex to inferior temporal regions in the early time window that was induced by subliminal priming. In the later time window, significant enhancement of bidirectional causal flow between these two regions underlying subliminal priming was observed. Results suggest that unconscious processing of words influences not only local activity of individual brain regions but also the dynamics of neural communication between those regions.

  19. The evolutionary psychology of left and right: costs and benefits of lateralization.

    Science.gov (United States)

    Vallortigara, Giorgio

    2006-09-01

    Why do the left and right sides of the vertebrate brain play different functions? Having a lateralized brain, in which each hemisphere carries out different functions, is ubiquitous among vertebrates. The different specialization of the left and right side of the brain may increase brain efficiency--and some evidence for that is reported here. However, lateral biases due to brain lateralization (such as preferences in the use of a limb or, in animals with laterally placed eyes, of a visual hemifield) usually occur at the population level, with most individuals showing similar direction of bias. Individual brain efficiency does not require the alignment of lateralization in the population. Why then are not left--and right-type individuals equally common? Not only humans, but most vertebrates show a similar pattern. For instance, in the paper I report evidence that most toads, chickens, and fish react faster when a predator approaches from the left. I argue that invoking individual brain efficiency (lateralization may increase fitness), evolutionary chance or direct genetic mechanisms cannot explain this widespread pattern. Instead, using concepts from mathematical theory of games, I show that alignment of lateralization at the population level may arise as an "evolutionarily stable strategy" when individually asymmetrical organisms must coordinate their behavior with that of other asymmetrical organisms. Thus, the population structure of lateralization may result from genes specifying the direction of asymmetries which have been selected under "social" pressures.

  20. Surgery in temporal lobe epilepsy patients without cranial MRI lateralization.

    Science.gov (United States)

    Gomceli, Y B; Erdem, A; Bilir, E; Kutlu, G; Kurt, S; Erden, E; Karatas, A; Erbas, C; Serdaroglu, A

    2006-03-01

    High resolution MRI is very important in the evaluations of patients with intractable temporal lobe epilepsy in preoperative investigations. Morphologic abnormalities on cranial MRI usually indicate the epileptogenic focus. Intractable TLE patients who have normal cranial MRI or bilateral hippocampal atrophy may have a chance for surgery if a certain epileptogenic focus is determined. We evaluated the patients who were monitorized in Gazi University Medical Faculty Epilepsy Center from October 1997 to April 2004. Seventy three patients, who had a temporal epileptogenic focus, underwent anterior temporal lobectomy at Ankara University Medical Faculty Department of Neurosurgery. Twelve of them (16, 4%), did not have any localizing structural lesion on cranial MRI. Of the 12 patients examined 6 had normal findings and 6 had bilateral hippocampal atrophy. Of these 12 patients, 6 (50%) were women and 6 (50%) were men. The ages of patients ranged from 7 to 37 (mean: 24.5). Preoperatively long-term scalp video-EEG monitoring, cranial MRI, neuropsychological tests, and Wada test were applied in all patients. Five patients, whose investigations resulted in conflicting data, underwent invasive monitoring by the use of subdural strips. The seizure outcome of patients were classified according to Engel with postsurgical follow-up ranging from 11 to 52 (median: 35.7) months. Nine patients (75%) were classified into Engel's Class I and the other 3 patients (25%) were placed into Engel's Class II. One patient who was classified into Engel's Class II had additional psychiatric problems. The other patient had two different epileptogenic foci independent from each other in her ictal EEG. One of them localized in the right anterior temporal area, the other was in the right frontal lobe. She was classified in Engel's Class II and had no seizure originating from temporal epileptic focus, but few seizures originating from the frontal region continued after the surgery. In conclusion

  1. Left Superior Temporal Gyrus Is Coupled to Attended Speech in a Cocktail-Party Auditory Scene.

    Science.gov (United States)

    Vander Ghinst, Marc; Bourguignon, Mathieu; Op de Beeck, Marc; Wens, Vincent; Marty, Brice; Hassid, Sergio; Choufani, Georges; Jousmäki, Veikko; Hari, Riitta; Van Bogaert, Patrick; Goldman, Serge; De Tiège, Xavier

    2016-02-03

    Using a continuous listening task, we evaluated the coupling between the listener's cortical activity and the temporal envelopes of different sounds in a multitalker auditory scene using magnetoencephalography and corticovocal coherence analysis. Neuromagnetic signals were recorded from 20 right-handed healthy adult humans who listened to five different recorded stories (attended speech streams), one without any multitalker background (No noise) and four mixed with a "cocktail party" multitalker background noise at four signal-to-noise ratios (5, 0, -5, and -10 dB) to produce speech-in-noise mixtures, here referred to as Global scene. Coherence analysis revealed that the modulations of the attended speech stream, presented without multitalker background, were coupled at ∼0.5 Hz to the activity of both superior temporal gyri, whereas the modulations at 4-8 Hz were coupled to the activity of the right supratemporal auditory cortex. In cocktail party conditions, with the multitalker background noise, the coupling was at both frequencies stronger for the attended speech stream than for the unattended Multitalker background. The coupling strengths decreased as the Multitalker background increased. During the cocktail party conditions, the ∼0.5 Hz coupling became left-hemisphere dominant, compared with bilateral coupling without the multitalker background, whereas the 4-8 Hz coupling remained right-hemisphere lateralized in both conditions. The brain activity was not coupled to the multitalker background or to its individual talkers. The results highlight the key role of listener's left superior temporal gyri in extracting the slow ∼0.5 Hz modulations, likely reflecting the attended speech stream within a multitalker auditory scene. When people listen to one person in a "cocktail party," their auditory cortex mainly follows the attended speech stream rather than the entire auditory scene. However, how the brain extracts the attended speech stream from the whole

  2. [Left lateral gaze paresis due to subcortical hematoma in the right precentral gyrus].

    Science.gov (United States)

    Sato, K; Takamori, M

    1998-03-01

    We report a case of transient left lateral gaze paresis due to a hemorrhagic lesion restricted in the right precentral gyrus. A 74-year-old female experienced a sudden clumsiness of the left upper extremity. A neurological examination revealed a left central facial paresis, distal dominant muscle weakness in the left upper limb and left lateral gaze paresis. There were no other focal neurological signs. Laboratory data were all normal. Brain CTs and MRIs demonstrated a subcortical hematoma in the right precentral gyrus. The neurological symptoms and signs disappeared over seven days. A recent physiological study suggested that the human frontal eye field (FEF) is located in the posterior part of the middle frontal gyrus (Brodmann's area 8) and the precentral gyrus around the precentral sulcus. More recent studies stressed the role of the precentral sulcus and the precentral gyrus. Our case supports those physiological findings. The hematoma affected both the FEF and its underlying white matter in our case. We assume the lateral gaze paresis is attributable to the disruption of the fibers from the FEF. It is likely that fibers for motor control of the face, upper extremity, and lateral gaze lie adjacently in the subcortical area.

  3. Increased cortical thickness and altered functional connectivity of the right superior temporal gyrus in left-handers.

    Science.gov (United States)

    Li, Meiling; Chen, Heng; Wang, Junping; Liu, Feng; Wang, Yifeng; Lu, Fengmei; Yu, Chunshui; Chen, Huafu

    2015-01-01

    Altered structure in the temporal cortex has been implicated in the variable language laterality of left-handers (LH). The neuroanatomy of language lateralization and the corresponding synchronous functional connectivity (FC) in handedness cohorts are not, however, fully understood. We used structural and resting-state functional magnetic resonance imaging (fMRI) data to investigate the effect of altered cortical thickness on FC in LH and right-handers (RH). Whole-brain cortical thickness was calculated and compared between the LH and RH. We observed increased cortical thickness in the right superior temporal gyrus (STG) in the LH. A further FC analysis was conducted between the right STG and the remaining voxels in the brain. Compared with RH, the LH showed significantly higher FC in the left STG, right occipital cortex, and lower FC in the left inferior frontal gyrus and supramarginal gyrus. Our findings suggest that LH have atypical connectivity in the language network, with an enhanced role of the STG, findings which provide novel insights into the structural and functional substrates underlying the atypical language development of left-handed individuals. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Mesial temporal lobe epilepsy lateralization using SPHARM-based features of hippocampus and SVM

    Science.gov (United States)

    Esmaeilzadeh, Mohammad; Soltanian-Zadeh, Hamid; Jafari-Khouzani, Kourosh

    2012-02-01

    This paper improves the Lateralization (identification of the epileptogenic hippocampus) accuracy in Mesial Temporal Lobe Epilepsy (mTLE). In patients with this kind of epilepsy, usually one of the brain's hippocampi is the focus of the epileptic seizures, and resection of the seizure focus is the ultimate treatment to control or reduce the seizures. Moreover, the epileptogenic hippocampus is prone to shrinkage and deformation; therefore, shape analysis of the hippocampus is advantageous in the preoperative assessment for the Lateralization. The method utilized for shape analysis is the Spherical Harmonics (SPHARM). In this method, the shape of interest is decomposed using a set of bases functions and the obtained coefficients of expansion are the features describing the shape. To perform shape comparison and analysis, some pre- and post-processing steps such as "alignment of different subjects' hippocampi" and the "reduction of feature-space dimension" are required. To this end, first order ellipsoid is used for alignment. For dimension reduction, we propose to keep only the SPHARM coefficients with maximum conformity to the hippocampus shape. Then, using these coefficients of normal and epileptic subjects along with 3D invariants, specific lateralization indices are proposed. Consequently, the 1536 SPHARM coefficients of each subject are summarized into 3 indices, where for each index the negative (positive) value shows that the left (right) hippocampus is deformed (diseased). Employing these indices, the best achieved lateralization accuracy for clustering and classification algorithms are 85% and 92%, respectively. This is a significant improvement compared to the conventional volumetric method.

  5. Intracerebral stimulation of left and right ventral temporal cortex during object naming.

    Science.gov (United States)

    Bédos Ulvin, Line; Jonas, Jacques; Brissart, Hélène; Colnat-Coulbois, Sophie; Thiriaux, Anne; Vignal, Jean-Pierre; Maillard, Louis

    2017-12-01

    While object naming is traditionally considered asa left hemisphere function, neuroimaging studies have reported activations related to naming in the ventral temporal cortex (VTC) bilaterally. Our aim was to use intracerebral electrical stimulation to specifically compare left and right VTC in naming. In twenty-three epileptic patients tested for visual object naming during stimulation, the proportion of naming impairments was significantly higher in the left than in the right VTC (31.3% vs 13.6%). The highest proportions of positive naming sites were found in the left fusiform gyrus and occipito-temporal sulcus (47.5% and 31.8%). For 17 positive left naming sites, an additional semantic picture matching was carried out, always successfully performed. Our results showed the enhanced role of the left compared to the right VTC in naming and suggest that it may be involved in lexical retrieval rather than in semantic processing. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Computer aided diagnosis and localization of lateralized temporal lobe epilepsy using interictal FDG-PET

    Directory of Open Access Journals (Sweden)

    Wesley Thomas Kerr

    2013-04-01

    Full Text Available Interictal FDG-PET (iPET is a core tool for localizing the epileptogenic focus, potentially before structural MRI, that does not require rare and transient epileptiform discharges or seizures on EEG. The visual interpretation of iPET is challenging and requires years of epilepsy-specific expertise. We have developed an automated computer-aided diagnostic (CAD tool that has the potential to work both independent of and synergistically with expert analysis. Our tool operates on distributed metabolic changes across the whole brain measured by iPET to both diagnose and lateralize temporal lobe epilepsy. When diagnosing left temporal lobe epilepsy (LTLE or right TLE (RTLE versus non-epileptic seizures (NES, our accuracy in reproducing the results of the gold standard long term video-EEG monitoring was 82% (95% confidence interval [CI] 69-90% or 88% (95% CI 76-94%, respectively. The classifier that both diagnosed and lateralized the disease had overall accuracy of 76% (95% CI 66-84%, where 89% (95% CI 77-96% of patients correctly identified with epilepsy were correctly lateralized. When identifying LTLE, our CAD tool utilized metabolic changes across the entire brain. By contrast, only temporal regions and the right frontal lobe cortex, were needed to identify RTLE accurately, a finding consistent with clinical observations and indicative of a potential pathophysiological difference between RTLE and LTLE. The goal of CADs is to complement—not replace—expert analysis. In our dataset, the accuracy of manual analysis of iPET (~80% was similar to CAD. The square correlation between our CAD tool and manual analysis, however, was only 30%, indicating that our CAD tool does not recreate manual analysis. The addition of clinical information to our CAD, however, did not substantively change performance. These results suggest that automated analysis might provide clinically valuable information to focus treatment more effectively.

  7. Laparoscopic left lateral sectionectomy with the use of Habib 4X: technical aspects.

    Science.gov (United States)

    Zacharoulis, Dimitris; Sioka, Eleni; Tzovaras, George; Jiao, Long R; Habib, Nagy

    2013-06-01

    Various techniques and energy-based devices have been used to minimize the blood loss during transection of the liver parenchyma laparoscopically. The laparoscopic Habib™ 4X sealer (Rita Medical Systems, Inc., Fremont, CA) is a promising device using bipolar radiofrequency energy. The purpose of the study was to test the safety and the efficiency of the device in laparoscopic left lateral sectionectomy. Five patients underwent laparoscopic left lateral sectionectomy using the laparoscopic Habib 4X in a period of 12 months. Indications for liver resection were hepatocellular carcinoma in 2 cirrhotic patients and colorectal cancer liver metastasis in 3 patients. Technical aspects were analyzed. All the patients underwent formal laparoscopic left lateral sectionectomy. The Pringle maneuver was not applied in any of the patients. Mean operative time was 75 minutes (range, 60-90 minutes). Bleeding control along the transection line was satisfactory. No conversion to laparotomy was required. Operative blood loss was minimal. No blood transfusion was recorded. The postoperative period was uneventful. Median hospital stay was 3 days (range, 2-5 days). Histopathology revealed that the margins were disease free. Laparoscopic left lateral segmentectomy with the use of Habib 4X proved safe and efficient. This technique may be an initial step for surgeons shifting to laparoscopic liver surgery provided they have previous experience in laparoscopic and liver surgery. Well-designed controlled randomized studies are needed in order to evaluate further the role of the device used in the present study in minimally invasive liver surgery.

  8. Beyond Hemispheric Dominance: Brain Regions Underlying the Joint Lateralization of Language and Arithmetic to the Left Hemisphere

    Science.gov (United States)

    Pinel, Philippe; Dehaene, Stanislas

    2010-01-01

    Language and arithmetic are both lateralized to the left hemisphere in the majority of right-handed adults. Yet, does this similar lateralization reflect a single overall constraint of brain organization, such an overall "dominance" of the left hemisphere for all linguistic and symbolic operations? Is it related to the lateralization of specific…

  9. [Effects of acupuncture at left and right Hegu (LI 4) for cerebral function laterality].

    Science.gov (United States)

    Wang, Linying; Xu, Chunsheng; Zhu, Yifang; Li, Chuanfu; Yang, Jun

    2015-08-01

    To explore the cerebral function laterality of acupuncture at left and right Hegu (LI 4) by using functional magnetic resonance imaging (fMRI) and provide objective evidences for side selection of Hegu (LI 4) in the clinical application. Eighty healthy volunteers were randomly divided into a left-acupoint group and a right-acupoint group, and they were treated with acupuncture at left Hegu (LI 4) and right Hegu (LI 4) respectively. After the arrival of qi, the task-state fMRI data in both groups was collected, and analysis of functional neuroimages (AFNI) software was used to perform intra-group and between-group comparisons. After acupuncture, acupuncture feelings were recorded and MGH acupuncture sensation scale (MASS) was recorded. The difference of MASS between the two groups was not significant (P>0. 05). The result of left-acupoint group showed an increased signal on right cerebral hemisphere, while the right-acupoint group showed extensive signal changes in both cerebral hemispheres. The analysis between left-acupoint group and retroflex right-acupoint group showed differences in brain areas. The central effect of acupuncture at left and right Hegu (LI 4) is dissymmetry, indicating right hemisphere laterality. The right lobus insularis and cingulate gyrus may be the key regions in the acupuncture at Hegu (LI 4).

  10. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

    Energy Technology Data Exchange (ETDEWEB)

    Uchida, R.R.; Del-Ben, C.M.; Araujo, D.; Crippa, J.A.; Graeff, F.G. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Neurologia e Psicologia Medica]. E-mail: fgraeff@keynet.com.br; Santos, A.C. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Clinica Medica; Guimaraes, F.S. [Sao Paulo Univ., Ribeirao Preto, SP (Brazil). Dept. de Farmacologia

    2003-07-01

    Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t{sub 21} = 2.37, P = 0.028). In addition, there was a trend (P values between 0.05 and 0.10) to smaller volumes of the right temporal lobe (7%, t{sub 21} = 1.99, P = 0.06), right amygdala (8%, t{sub 21} = 1.83, P = 0.08), left amygdala (5%, t{sub 21} = 1.78, P 0.09) and left hippocampus (9%, t{sub 21} = 1.93, P = 0.07) in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025), with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures. (author)

  11. Decreased left temporal lobe volume of panic patients measured by magnetic resonance imaging

    International Nuclear Information System (INIS)

    Uchida, R.R.; Del-Ben, C.M.; Araujo, D.; Crippa, J.A.; Graeff, F.G.; Santos, A.C.; Guimaraes, F.S.

    2003-01-01

    Reported neuroimaging studies have shown functional and morphological changes of temporal lobe structures in panic patients, but only one used a volumetric method. The aim of the present study was to determine the volume of temporal lobe structures in patients with panic disorder, measured by magnetic resonance imaging. Eleven panic patients and eleven controls matched for age, sex, handedness, socioeconomic status and years of education participated in the study. The mean volume of the left temporal lobe of panic patients was 9% smaller than that of controls (t 21 = 2.37, P = 0.028). In addition, there was a trend (P values between 0.05 and 0.10) to smaller volumes of the right temporal lobe (7%, t 21 = 1.99, P = 0.06), right amygdala (8%, t 21 = 1.83, P = 0.08), left amygdala (5%, t 21 = 1.78, P 0.09) and left hippocampus (9%, t 21 = 1.93, P = 0.07) in panic patients compared to controls. There was a positive correlation between left hippocampal volume and duration of panic disorder (r = 0.67, P = 0.025), with recent cases showing more reduction than older cases. The present results show that panic patients have a decreased volume of the left temporal lobe and indicate the presence of volumetric abnormalities of temporal lobe structures. (author)

  12. Automatic interpretation of F-18-FDG brain PET using artificial neural network: discrimination of medial and lateral temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jae Sung; Lee, Dong Soo; Kim, Seok Ki; Park, Kwang Suk; Lee, Sang Kun; Chung, June Key; Lee, Myung Chul [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2004-06-01

    We developed a computer-aided classifier using artificial neural network (ANN) to discriminate the cerebral metabolic pattern of medial and lateral temporal lobe epilepsy (TLE). We studied brain F-18-FDG PET images of 113 epilepsy patients surgically and pathologically proven as medial TLE (left 41, right 42) or lateral TLE (left 14, right 16). PET images were spatially transformed onto a standard template and normalized to the mean counts of cortical regions. Asymmetry indices for predefined 17 mirrored regions to hemispheric midline and those for medial and lateral temporal lobes were used as input features for ANN. ANN classifier was composed of 3 independent multi-layered perceptions (1 for left/right lateralization and 2 for medial/lateral discrimination) and trained to interpret metabolic patterns and produce one of 4 diagnoses (L/R medial TLE or L/R lateral TLE). Randomly selected 8 images from each group were used to train the ANN classifier and remaining 81 images were used as test sets. The accuracy of the diagnosis with ANN was estimated by averaging the agreement rates of independent 50 trials and compared to that of nuclear medicine experts. The accuracy in lateralization was 89% by the human experts and 90% by the ANN classifier. Overall accuracy in localization of epileptogenic zones by the ANN classifier was 69%, which was comparable to that by the human experts (72%). We conclude that ANN classifier performed as well as human experts and could be potentially useful supporting tool for the differential diagnosis of TLE.

  13. Automatic interpretation of F-18-FDG brain PET using artificial neural network: discrimination of medial and lateral temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Lee, Jae Sung; Lee, Dong Soo; Kim, Seok Ki; Park, Kwang Suk; Lee, Sang Kun; Chung, June Key; Lee, Myung Chul

    2004-01-01

    We developed a computer-aided classifier using artificial neural network (ANN) to discriminate the cerebral metabolic pattern of medial and lateral temporal lobe epilepsy (TLE). We studied brain F-18-FDG PET images of 113 epilepsy patients surgically and pathologically proven as medial TLE (left 41, right 42) or lateral TLE (left 14, right 16). PET images were spatially transformed onto a standard template and normalized to the mean counts of cortical regions. Asymmetry indices for predefined 17 mirrored regions to hemispheric midline and those for medial and lateral temporal lobes were used as input features for ANN. ANN classifier was composed of 3 independent multi-layered perceptions (1 for left/right lateralization and 2 for medial/lateral discrimination) and trained to interpret metabolic patterns and produce one of 4 diagnoses (L/R medial TLE or L/R lateral TLE). Randomly selected 8 images from each group were used to train the ANN classifier and remaining 81 images were used as test sets. The accuracy of the diagnosis with ANN was estimated by averaging the agreement rates of independent 50 trials and compared to that of nuclear medicine experts. The accuracy in lateralization was 89% by the human experts and 90% by the ANN classifier. Overall accuracy in localization of epileptogenic zones by the ANN classifier was 69%, which was comparable to that by the human experts (72%). We conclude that ANN classifier performed as well as human experts and could be potentially useful supporting tool for the differential diagnosis of TLE

  14. Insights into Intrinsic Brain Networks based on Graph Theory and PET in right- compared to left-sided Temporal Lobe Epilepsy

    OpenAIRE

    Thomas Vanicek; Andreas Hahn; Tatjana Traub-Weidinger; Eva Hilger; Marie Spies; Wolfgang Wadsak; Rupert Lanzenberger; Ekaterina Pataraia; Susanne Asenbaum-Nan

    2016-01-01

    The human brain exhibits marked hemispheric differences, though it is not fully understood to what extent lateralization of the epileptic focus is relevant. Preoperative [18F]FDG-PET depicts lateralization of seizure focus in patients with temporal lobe epilepsy and reveals dysfunctional metabolic brain connectivity. The aim of the present study was to compare metabolic connectivity, inferred from inter-regional [18F]FDG PET uptake correlations, in right-sided (RTLE; n?=?30) and left-sided TL...

  15. A functional MRI study of language networks in left medial temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Yu Aihong; Wang Xiaoyi; Xu Guoqing; Li Yongjie; Qin Wen; Li Kuncheng; Wang, Yuping

    2011-01-01

    Purpose: The purpose of this study was to investigate the abnormality of language networks in left medial temporal lobe epilepsy (MTLE) using fMRI. Materials and methods: Eight patients with left MTLE and 15 healthy subjects were evaluated. An auditory semantic judgment (AJ) paradigm was used. The fMRI data were collected on a 3T MR system and analyzed by AFNI (analysis of functional neuroimages) to generate the activation map. Results: Behavioral data showed that the reaction time of the left MTLE patients was significantly longer than that of controls on the AJ task (t = -3.396, P < 0.05). The left MTLE patients also exhibited diffusively decreased activation in the AJ task. Right hemisphere dominance of Broca's and Wernicke's areas was demonstrated in left MTLE patients. Conclusions: Long-term activation of spikes in left MTLE patients results in language impairment, which is associated with an abnormality of the brain neural network.

  16. Left hemispheric dominance of vestibular processing indicates lateralization of cortical functions in rats.

    Science.gov (United States)

    Best, Christoph; Lange, Elena; Buchholz, Hans-Georg; Schreckenberger, Mathias; Reuss, Stefan; Dieterich, Marianne

    2014-11-01

    Lateralization of cortical functions such as speech dominance, handedness and processing of vestibular information are present not only in humans but also in ontogenetic older species, e.g. rats. In human functional imaging studies, the processing of vestibular information was found to be correlated with the hemispherical dominance as determined by the handedness. It is located mainly within the right hemisphere in right handers and within the left hemisphere in left handers. Since dominance of vestibular processing is unknown in animals, our aim was to study the lateralization of cortical processing in a functional imaging study applying small-animal positron emission tomography (microPET) and galvanic vestibular stimulation in an in vivo rat model. The cortical and subcortical network processing vestibular information could be demonstrated and correlated with data from other animal studies. By calculating a lateralization index as well as flipped region of interest analyses, we found that the vestibular processing in rats follows a strong left hemispheric dominance independent from the "handedness" of the animals. These findings support the idea of an early hemispheric specialization of vestibular cortical functions in ontogenetic older species.

  17. [Two cases of mesial temporal lobe epilepsy associated with old intracerebral hemorrhage in the lateral temporal lobe without "dual pathology"].

    Science.gov (United States)

    Morioka, T; Nishio, S; Hisada, K; Muraishi, M; Ishibashi, H; Mamiya, K; Ohfu, M; Fukui, M

    1998-05-01

    Two cases of intractable temporal lobe epilepsy associated with old intracerebral hemorrhage in the lateral temporal lobe were reported. Although preoperative magnetic resonance imaging (MRI) failed to reveal hippocampal atrophy with T2 hyperintensity, electrocorticographic (ECoG) recording with chronic invasive subdural electrodes indicated the mesial temporal lobe to be an ictal onset zone. After anterior temporal lobectomy involving the lesion and hippocampectomy, the patients became seizure-free. Hippocampal sclerosis, namely "dual pathology", was not noted on histological examination. Careful ECoG recording with chronic subdural electrodes is mandatory even when the preoperative MRI does not demonstrate the radiological hippocampal sclerosis.

  18. Nonvisual spatial navigation fMRI lateralizes mesial temporal lobe epilepsy in a patient with congenital blindness.

    Science.gov (United States)

    Toller, Gianina; Adhimoolam, Babu; Grunwald, Thomas; Huppertz, Hans-Jürgen; König, Kristina; Jokeit, Hennric

    2015-01-01

    Nonvisual spatial navigation functional magnetic resonance imaging (fMRI) may help clinicians determine memory lateralization in blind individuals with refractory mesial temporal lobe epilepsy (MTLE). We report on an exceptional case of a congenitally blind woman with late-onset left MTLE undergoing presurgical memory fMRI. To activate mesial temporal structures despite the lack of visual memory, the patient was requested to recall familiar routes using nonvisual multisensory and verbal cues. Our findings demonstrate the diagnostic value of a nonvisual fMRI task to lateralize MTLE despite congenital blindness and may therefore contribute to the risk assessment for postsurgical amnesia in rare cases with refractory MTLE and accompanying congenital blindness.

  19. Resting-state functional connectivity predicts the strength of hemispheric lateralization for language processing in temporal lobe epilepsy and normals.

    Science.gov (United States)

    Doucet, Gaëlle E; Pustina, Dorian; Skidmore, Christopher; Sharan, Ashwini; Sperling, Michael R; Tracy, Joseph I

    2015-01-01

    In temporal lobe epilepsy (TLE), determining the hemispheric specialization for language before surgery is critical to preserving a patient's cognitive abilities post-surgery. To date, the major techniques utilized are limited by the capacity of patients to efficiently realize the task. We determined whether resting-state functional connectivity (rsFC) is a reliable predictor of language hemispheric dominance in right and left TLE patients, relative to controls. We chose three subregions of the inferior frontal cortex (pars orbitalis, pars triangularis, and pars opercularis) as the seed regions. All participants performed both a verb generation task and a resting-state fMRI procedure. Based on the language task, we computed a laterality index (LI) for the resulting network. This revealed that 96% of the participants were left-hemisphere dominant, although there remained a large degree of variability in the strength of left lateralization. We tested whether LI correlated with rsFC values emerging from each seed. We revealed a set of regions that was specific to each group. Unique correlations involving the epileptic mesial temporal lobe were revealed for the right and left TLE patients, but not for the controls. Importantly, for both TLE groups, the rsFC emerging from a contralateral seed was the most predictive of LI. Overall, our data depict the broad patterns of rsFC that support strong versus weak left hemisphere language laterality. This project provides the first evidence that rsFC data may potentially be used on its own to verify the strength of hemispheric dominance for language in impaired or pathologic populations. © 2014 Wiley Periodicals, Inc.

  20. Accelerated long-term forgetting in temporal lobe epilepsy: evidence of improvement after left temporal pole lobectomy.

    Science.gov (United States)

    Gallassi, Roberto; Sambati, Luisa; Poda, Roberto; Stanzani Maserati, Michelangelo; Oppi, Federico; Giulioni, Marco; Tinuper, Paolo

    2011-12-01

    Accelerated long term forgetting (ALF) is a characteristic cognitive aspect in patients affected by temporal lobe epilepsy that is probably due to an impairment of memory consolidation and retrieval caused by epileptic activity in hippocampal and parahippocampal regions. We describe a case of a patient with TLE who showed improvement in ALF and in remote memory impairment after an anterior left temporal pole lobectomy including the uncus and amygdala. Our findings confirm that impairment of hippocampal functioning leads to pathological ALF, whereas restoration of hippocampal functioning brings ALF to a level comparable to that of controls. Copyright © 2011 Elsevier Inc. All rights reserved.

  1. Predicting the laterality of temporal lobe epilepsy from PET, MRI, and DTI: A multimodal study

    Directory of Open Access Journals (Sweden)

    Dorian Pustina

    2015-01-01

    Full Text Available Pre-surgical evaluation of patients with temporal lobe epilepsy (TLE relies on information obtained from multiple neuroimaging modalities. The relationship between modalities and their combined power in predicting the seizure focus is currently unknown. We investigated asymmetries from three different modalities, PET (glucose metabolism, MRI (cortical thickness, and diffusion tensor imaging (DTI; white matter anisotropy in 28 left and 30 right TLE patients (LTLE and RTLE. Stepwise logistic regression models were built from each modality separately and from all three combined, while bootstrapped methods and split-sample validation verified the robustness of predictions. Among all multimodal asymmetries, three PET asymmetries formed the best predictive model (100% success in full sample, >95% success in split-sample validation. The combinations of PET with other modalities did not perform better than PET alone. Probabilistic classifications were obtained for new clinical cases, which showed correct lateralization for 7/7 new TLE patients (100% and for 4/5 operated patients with discordant or non-informative PET reports (80%. Metabolism showed closer relationship with white matter in LTLE and closer relationship with gray matter in RTLE. Our data suggest that metabolism is a powerful modality that can predict seizure laterality with high accuracy, and offers high value for automated predictive models. The side of epileptogenic focus can affect the relationship of metabolism with brain structure. The data and tools necessary to obtain classifications for new TLE patients are made publicly available.

  2. Temporal lobe pathology in amyotrophic lateral sclerosis. Do amyotrophic lateral sclerosis and Alzheimer's disease share a common etiological factor?

    NARCIS (Netherlands)

    Smitt, P. A.; Troost, D.; Louwerse, E. S.; de Jong, J. M.; van Kessel, D. T.; de Leeuw, M. A.

    1993-01-01

    An autopsy study was performed on temporal lobe samples from 20 non-demented patients with amyotrophic lateral sclerosis (ALS), 17 age-matched non-demented controls and 4 Alzheimer's disease (AD) patients. Formalin fixed, paraffin embedded sections from the hippocampus with adjacent parahippocampal

  3. BOLD Response to Motion Verbs in Left Posterior Middle Temporal Gyrus during Story Comprehension

    Science.gov (United States)

    Wallentin, Mikkel; Nielsen, Andreas Hojlund; Vuust, Peter; Dohn, Anders; Roepstorff, Andreas; Lund, Torben Ellegaard

    2011-01-01

    A primary focus within neuroimaging research on language comprehension is on the distribution of semantic knowledge in the brain. Studies have shown that the left posterior middle temporal gyrus (LPMT), a region just anterior to area MT/V5, is important for the processing of complex action knowledge. It has also been found that motion verbs cause…

  4. Choosing words: left hemisphere, right hemisphere, or both? Perspective on the lateralization of word retrieval

    Science.gov (United States)

    Ries, Stephanie K.; Dronkers, Nina F.; Knight, Robert T.

    2015-01-01

    Language is considered to be one of the most lateralized human brain functions. Left hemisphere dominance for language has been consistently confirmed in clinical and experimental settings and constitutes one of the main axioms of neurology and neuroscience. However, functional neuroimaging studies are finding that the right hemisphere also plays a role in diverse language functions. Critically, the right hemisphere may also compensate for the loss or degradation of language functions following extensive stroke-induced damage to the left hemisphere. Here, we review studies that focus on our ability to choose words as we speak. Although fluidly performed in individuals with intact language, this process is routinely compromised in aphasic patients. We suggest that parceling word retrieval into its sub-processes—lexical activation and lexical selection—and examining which of these can be compensated for after left hemisphere stroke can advance the understanding of the lateralization of word retrieval in speech production. In particular, the domain-general nature of the brain regions associated with each process may be a helpful indicator of the right hemisphere's propensity for compensation. PMID:26766393

  5. Processing of Words and Faces by Patients with Left and Right Temporal Lobe Epilepsy

    Directory of Open Access Journals (Sweden)

    Andrew W. Ellis

    1991-01-01

    Full Text Available Tests of word and face processing were given to patients with complex partial epilepsy focussed on the left or right temporal lobe, and to non-epileptic control subjects. The left TLE group showed the greatest impairment on object naming and on reading tests, but the right TLE group also showed a lesser impairment relative to the normal control subjects on both tests. The right TLE group was selectively impaired on distinguishing famous from non-famous faces while the left TLE group was impaired at naming famous faces they had successfully recognized as familiar. There was no significant difference between the three groups on recognition memory for words. The implications of the results for theories of the role of the temporal lobes in word and face processing, and the possible neural mechanisms responsible for the deficits in TLE patients, are discussed.

  6. Investigation of left and right lateral fluid percussion injury in C57BL6/J mice: In vivo functional consequences.

    Science.gov (United States)

    Schurman, Lesley D; Smith, Terry L; Morales, Anthony J; Lee, Nancy N; Reeves, Thomas M; Phillips, Linda L; Lichtman, Aron H

    2017-07-13

    Although rodent models of traumatic brain injury (TBI) reliably produce cognitive and motor disturbances, behavioral characterization resulting from left and right hemisphere injuries remains unexplored. Here we examined the functional consequences of targeting the left versus right parietal cortex in lateral fluid percussion injury, on Morris water maze (MWM) spatial memory tasks (fixed platform and reversal) and neurological motor deficits (neurological severity score and rotarod). In the MWM fixed platform task, right lateral injury produced a small delay in acquisition rate compared to left. However, injury to either hemisphere resulted in probe trial deficits. In the MWM reversal task, left-right performance deficits were not evident, though left lateral injury produced mild acquisition and probe trial deficits compared to sham controls. Additionally, left and right injury produced similar neurological motor task deficits, impaired righting times, and lesion volumes. Injury to either hemisphere also produced robust ipsilateral, and modest contralateral, morphological changes in reactive microglia and astrocytes. In conclusion, left and right lateral TBI impaired MWM performance, with mild fixed platform acquisition rate differences, despite similar motor deficits, histological damage, and glial cell reactivity. Thus, while both left and right lateral TBI produce cognitive deficits, laterality in mouse MWM learning and memory merits consideration in the investigation of TBI-induced cognitive consequences. Copyright © 2017. Published by Elsevier B.V.

  7. Reduced sensitivity of the N400 and late positive component to semantic congruity and word repetition in left temporal lobe epilepsy.

    Science.gov (United States)

    Olichney, John M; Riggins, Brock R; Hillert, Dieter G; Nowacki, Ralph; Tecoma, Evelyn; Kutas, Marta; Iragui, Vicente J

    2002-07-01

    We studied 14 patients with well-characterized refractory temporal lobe epilepsy (TLE), 7 with right temporal lobe epilepsy (RTE) and 7 with left temporal lobe epilepsy (LTE), on a word repetition ERP experiment. Much prior literature supports the view that patients with left TLE are more likely to develop verbal memory deficits, often attributable to left hippocampal sclerosis. Our main objectives were to test if abnormalities of the N400 or Late Positive Component (LPC, P600) were associated with a left temporal seizure focus, or left temporal lobe dysfunction. A minimum of 19 channels of EEG/EOG data were collected while subjects performed a semantic categorization task. Auditory category statements were followed by a visual target word, which were 50% "congruous" (category exemplars) and 50% "incongruous" (non-category exemplars) with the preceding semantic context. These auditory-visual pairings were repeated pseudo-randomly at time intervals ranging from approximately 10-140 seconds later. The ERP data were submitted to repeated-measures ANOVAs, which showed the RTE group had generally normal effects of word repetition on the LPC and the N400. Also, the N400 component was larger to incongruous than congruous new words, as is normally the case. In contrast, the LTE group did not have statistically significant effects of either word repetition or congruity on their ERPs (N400 or LPC), suggesting that this ERP semantic categorization paradigm is sensitive to left temporal lobe dysfunction. Further studies are ongoing to determine if these ERP abnormalities predict hippocampal sclerosis on histopathology, or outcome after anterior temporal lobectomy.

  8. Multivariate pattern analysis reveals anatomical connectivity differences between the left and right mesial temporal lobe epilepsy

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    Peng Fang

    2015-01-01

    Full Text Available Previous studies have demonstrated differences of clinical signs and functional brain network organizations between the left and right mesial temporal lobe epilepsy (mTLE, but the anatomical connectivity differences underlying functional variance between the left and right mTLE remain uncharacterized. We examined 43 (22 left, 21 right mTLE patients with hippocampal sclerosis and 39 healthy controls using diffusion tensor imaging. After the whole-brain anatomical networks were constructed for each subject, multivariate pattern analysis was applied to classify the left mTLE from the right mTLE and extract the anatomical connectivity differences between the left and right mTLE patients. The classification results reveal 93.0% accuracy for the left mTLE versus the right mTLE, 93.4% accuracy for the left mTLE versus controls and 90.0% accuracy for the right mTLE versus controls. Compared with the right mTLE, the left mTLE exhibited a different connectivity pattern in the cortical-limbic network and cerebellum. The majority of the most discriminating anatomical connections were located within or across the cortical-limbic network and cerebellum, thereby indicating that these disease-related anatomical network alterations may give rise to a portion of the complex of emotional and memory deficit between the left and right mTLE. Moreover, the orbitofrontal gyrus, cingulate cortex, hippocampus and parahippocampal gyrus, which exhibit high discriminative power in classification, may play critical roles in the pathophysiology of mTLE. The current study demonstrated that anatomical connectivity differences between the left mTLE and the right mTLE may have the potential to serve as a neuroimaging biomarker to guide personalized diagnosis of the left and right mTLE.

  9. Multivariate pattern analysis reveals anatomical connectivity differences between the left and right mesial temporal lobe epilepsy.

    Science.gov (United States)

    Fang, Peng; An, Jie; Zeng, Ling-Li; Shen, Hui; Chen, Fanglin; Wang, Wensheng; Qiu, Shijun; Hu, Dewen

    2015-01-01

    Previous studies have demonstrated differences of clinical signs and functional brain network organizations between the left and right mesial temporal lobe epilepsy (mTLE), but the anatomical connectivity differences underlying functional variance between the left and right mTLE remain uncharacterized. We examined 43 (22 left, 21 right) mTLE patients with hippocampal sclerosis and 39 healthy controls using diffusion tensor imaging. After the whole-brain anatomical networks were constructed for each subject, multivariate pattern analysis was applied to classify the left mTLE from the right mTLE and extract the anatomical connectivity differences between the left and right mTLE patients. The classification results reveal 93.0% accuracy for the left mTLE versus the right mTLE, 93.4% accuracy for the left mTLE versus controls and 90.0% accuracy for the right mTLE versus controls. Compared with the right mTLE, the left mTLE exhibited a different connectivity pattern in the cortical-limbic network and cerebellum. The majority of the most discriminating anatomical connections were located within or across the cortical-limbic network and cerebellum, thereby indicating that these disease-related anatomical network alterations may give rise to a portion of the complex of emotional and memory deficit between the left and right mTLE. Moreover, the orbitofrontal gyrus, cingulate cortex, hippocampus and parahippocampal gyrus, which exhibit high discriminative power in classification, may play critical roles in the pathophysiology of mTLE. The current study demonstrated that anatomical connectivity differences between the left mTLE and the right mTLE may have the potential to serve as a neuroimaging biomarker to guide personalized diagnosis of the left and right mTLE.

  10. Learning and memory and its relationship with the lateralization of epileptic focus in subjects with temporal lobe epilepsy

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    Daniel Fuentes

    2014-04-01

    Full Text Available Background : In medial temporal lobe epilepsy (MTLE, previous studies addressing the hemispheric laterality of epileptogenic focus and its relationship with learning and memory processes have reported controversial findings. Objective : To compare the performance of MTLE patients according to the location of the epileptogenic focus on the left (MTLEL or right temporal lobe (MTLER on tasks of episodic learning and memory for verbal and visual content. Methods : One hundred patients with MTLEL and one hundred patients with MTLER were tested with the following tasks: the Rey Auditory Verbal Learning Test (RAVLT and the Logical Memory-WMS-R to evaluate verbal learning and memory; and the Rey Visual Design Learning Test (RVDLT and the Visual Reproduction-WMS-R to evaluate visual learning and memory. Results : The MTLEL sample showed significantly worse performance on the RAVLT (p < 0.005 and on the Logical Memory tests (p < 0.01 than MTLER subjects. However, there were no significant between-group differences in regard to the visual memory tests. Discussion : Our findings suggest that verbal learning and memory abilities are dependent on the structural and functional integrity of the left temporal lobe, while visual abilities are less dependent on the right temporal lobe.

  11. Laparoscopic left lateral segmentectomy for metachronic metastases of small intestine adenocarcinoma: a case report

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    Sergio Renato Pais-Costa

    2011-12-01

    Full Text Available Hepatectomy has been the standard treatment for metachronic metastases of non-colorectal (NCR origin, mainly when the disease-free interval is more than two years. Laparoscopic hepatectomy has become the golden standard mainly for left side resections, due to lower morbidity, shorter hospital stay, early recovery and good cosmetic outcome. The authors report the case of a female patient with two metachronic metastases (ten years of disease-free survival, of non-colorectal origin (adenocarcinoma of small intestine, treated by laparoscopic left lateral segmentectomy (left hepatic lobectomy with success. The postoperative progress was satisfactory. To date, the patient has presented no tumoral recurrence (six months of follow-up period. Laparoscopic left lateral segmentectomy can be satisfactorily performed in selected cases of hepatic metastasis. This approach presents low morbidity and good cosmetic result. The lack of alternative treatments and the poor prognosis of untreated cases have justified surgical resection in order to increase overall survival. Nevertheless, this approach should be performed by hepatic surgery expertise teams trained on advanced laparoscopic procedures.A hepatectomia tem sido o tratamento padrão para metástase de origem não colorretal (NCR metacrônica, principalmente quando o intervalo livre de doença é maior do que dois anos. A hepatectomia por laparoscopia tem se tornado padrão principalmente para as ressecções à esquerda, haja vista a menor morbidade, menor tempo de internação, reabilitação precoce e melhor resultado estético. Os autores relatam um caso de paciente com duas metástases metacrônicas (10 anos de sobrevida livre de doença, de etiologia não colorretal (adenocarcinoma de intestino delgado, tratada com segmentectomia lateral esquerda (lobectomia hepática esquerda laparoscópica. Paciente apresentou boa evolução pós-operatória sem recidiva (seis meses de seguimento. Segmentectomia

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

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    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.

  13. White-matter microstructure and language lateralization in left-handers: a whole-brain MRI analysis.

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    Perlaki, Gabor; Horvath, Reka; Orsi, Gergely; Aradi, Mihaly; Auer, Tibor; Varga, Eszter; Kantor, Gyongyi; Altbäcker, Anna; John, Flora; Doczi, Tamas; Komoly, Samuel; Kovacs, Norbert; Schwarcz, Attila; Janszky, Jozsef

    2013-08-01

    Most people are left-hemisphere dominant for language. However the neuroanatomy of language lateralization is not fully understood. By combining functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI), we studied whether language lateralization is associated with cerebral white-matter (WM) microstructure. Sixteen healthy, left-handed women aged 20-25 were included in the study. Left-handers were targeted in order to increase the chances of involving subjects with atypical language lateralization. Language lateralization was determined by fMRI using a verbal fluency paradigm. Tract-based spatial statistics analysis of DTI data was applied to test for WM microstructural correlates of language lateralization across the whole brain. Fractional anisotropy and mean diffusivity were used as indicators of WM microstructural organization. Right-hemispheric language dominance was associated with reduced microstructural integrity of the left superior longitudinal fasciculus and left-sided parietal lobe WM. In left-handed women, reduced integrity of the left-sided language related tracts may be closely linked to the development of right hemispheric language dominance. Our results may offer new insights into language lateralization and structure-function relationships in human language system. Copyright © 2013 Elsevier Inc. All rights reserved.

  14. Disentangling the cognitive components supporting Austin Maze performance in left versus right temporal lobe epilepsy.

    Science.gov (United States)

    Hocking, Julia; Thomas, Hannah J; Dzafic, Ilvana; Williams, Rebecca J; Reutens, David C; Spooner, Donna M

    2013-12-01

    Neuropsychological tests requiring patients to find a path through a maze can be used to assess visuospatial memory performance in temporal lobe pathology, particularly in the hippocampus. Alternatively, they have been used as a task sensitive to executive function in patients with frontal lobe damage. We measured performance on the Austin Maze in patients with unilateral left and right temporal lobe epilepsy (TLE), with and without hippocampal sclerosis, compared to healthy controls. Performance was correlated with a number of other neuropsychological tests to identify the cognitive components that may be associated with poor Austin Maze performance. Patients with right TLE were significantly impaired on the Austin Maze task relative to patients with left TLE and controls, and error scores correlated with their performance on the Block Design task. The performance of patients with left TLE was also impaired relative to controls; however, errors correlated with performance on tests of executive function and delayed recall. The presence of hippocampal sclerosis did not have an impact on maze performance. A discriminant function analysis indicated that the Austin Maze alone correctly classified 73.5% of patients as having right TLE. In summary, impaired performance on the Austin Maze task is more suggestive of right than left TLE; however, impaired performance on this visuospatial task does not necessarily involve the hippocampus. The relationship of the Austin Maze task with other neuropsychological tests suggests that differential cognitive components may underlie performance decrements in right versus left TLE. © 2013.

  15. Cardiovascular responses to the change from the left lateral to the upright position in pregnant hypertensives.

    Science.gov (United States)

    Dyer, R A; Anthony, J; Ledeboer, Q; James, M F

    2004-03-01

    To evaluate by non-invasive means, the autonomically mediated changes in heart rate and blood pressure in response to postural change in pregnancy. Ninety-one patients were studied, of whom 17 were non-pregnant controls, 21 were normotensive parturients, 22 had non-proteinuric hypertension, and 31 were pre-eclamptics. In all patients the heart rate and blood pressure response to the change from the left lateral to the erect position was measured non-invasively, during the third trimester in the pregnant groups. The change from the left lateral to the erect position induced significantly greater mean changes (increases) in systolic blood pressure in the normotensive pregnant (PC) women than all other groups (Pchanges when comparing the PC, NP and H groups. The PE group exhibited a significantly greater increase in heart rate on adopting the erect position than all other groups. Pre-eclamptics exhibit smaller changes in blood pressure than normotensive pregnant patients and non-proteinuric hypertensives on standing, while producing an exaggerated heart rate response, indicating altered autonomic compensatory mechanisms in these patients.

  16. Hemispheric lateralization in an analysis of speech sounds. Left hemisphere dominance replicated in Japanese subjects.

    Science.gov (United States)

    Koyama, S; Gunji, A; Yabe, H; Oiwa, S; Akahane-Yamada, R; Kakigi, R; Näätänen, R

    2000-09-01

    Evoked magnetic responses to speech sounds [R. Näätänen, A. Lehtokoski, M. Lennes, M. Cheour, M. Huotilainen, A. Iivonen, M. Vainio, P. Alku, R.J. Ilmoniemi, A. Luuk, J. Allik, J. Sinkkonen and K. Alho, Language-specific phoneme representations revealed by electric and magnetic brain responses. Nature, 385 (1997) 432-434.] were recorded from 13 Japanese subjects (right-handed). Infrequently presented vowels ([o]) among repetitive vowels ([e]) elicited the magnetic counterpart of mismatch negativity, MMNm (Bilateral, nine subjects; Left hemisphere alone, three subjects; Right hemisphere alone, one subject). The estimated source of the MMNm was stronger in the left than in the right auditory cortex. The sources were located posteriorly in the left than in the right auditory cortex. These findings are consistent with the results obtained in Finnish [R. Näätänen, A. Lehtokoski, M. Lennes, M. Cheour, M. Huotilainen, A. Iivonen, M.Vainio, P.Alku, R.J. Ilmoniemi, A. Luuk, J. Allik, J. Sinkkonen and K. Alho, Language-specific phoneme representations revealed by electric and magnetic brain responses. Nature, 385 (1997) 432-434.][T. Rinne, K. Alho, P. Alku, M. Holi, J. Sinkkonen, J. Virtanen, O. Bertrand and R. Näätänen, Analysis of speech sounds is left-hemisphere predominant at 100-150 ms after sound onset. Neuroreport, 10 (1999) 1113-1117.] and English [K. Alho, J.F. Connolly, M. Cheour, A. Lehtokoski, M. Huotilainen, J. Virtanen, R. Aulanko and R.J. Ilmoniemi, Hemispheric lateralization in preattentive processing of speech sounds. Neurosci. Lett., 258 (1998) 9-12.] subjects. Instead of the P1m observed in Finnish [M. Tervaniemi, A. Kujala, K. Alho, J. Virtanen, R.J. Ilmoniemi and R. Näätänen, Functional specialization of the human auditory cortex in processing phonetic and musical sounds: A magnetoencephalographic (MEG) study. Neuroimage, 9 (1999) 330-336.] and English [K. Alho, J. F. Connolly, M. Cheour, A. Lehtokoski, M. Huotilainen, J. Virtanen, R. Aulanko

  17. Modulating phonemic fluency performance in healthy subjects with transcranial magnetic stimulation over the left or right lateral frontal cortex.

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    Smirni, Daniela; Turriziani, Patrizia; Mangano, Giuseppa Renata; Bracco, Martina; Oliveri, Massimiliano; Cipolotti, Lisa

    2017-07-28

    A growing body of evidence have suggested that non-invasive brain stimulation techniques, such as transcranial magnetic stimulation (TMS) and transcranial direct current stimulation (tDCS), can improve the performance of aphasic patients in language tasks. For example, application of inhibitory rTMS or tDCs over the right frontal lobe of dysphasic patients resulted in improved naming abilities. Several studies have also reported that in healthy controls (HC) tDCS application over the left prefrontal cortex (PFC) improve performance in naming and semantic fluency tasks. The aim of this study was to investigate in HC, for the first time, the effects of inhibitory repetitive TMS (rTMS) over left and right lateral frontal cortex (BA 47) on two phonemic fluency tasks (FAS or FPL). 44 right-handed HCs were administered rTMS or sham over the left or right lateral frontal cortex in two separate testing sessions, with a 24h interval, followed by the two phonemic fluency tasks. To account for possible practice effects, an additional 22 HCs were tested on only the phonemic fluency task across two sessions with no stimulation. We found that rTMS-inhibition over the left lateral frontal cortex significantly worsened phonemic fluency performance when compared to sham. In contrast, rTMS-inhibition over the right lateral frontal cortex significantly improved phonemic fluency performance when compared to sham. These results were not accounted for practice effects. We speculated that rTMS over the right lateral frontal cortex may induce plastic neural changes to the left lateral frontal cortex by suppressing interhemispheric inhibitory interactions. This resulted in an increased excitability (disinhibition) of the contralateral unstimulated left lateral frontal cortex, consequently enhancing phonemic fluency performance. Conversely, application of rTMS over the left lateral frontal cortex may induce a temporary, virtual lesion, with effects similar to those reported in left frontal

  18. Potential role of a cognitive rehabilitation program following left temporal lobe epilepsy surgery

    Directory of Open Access Journals (Sweden)

    Camila de Vasconcelos Geraldi

    Full Text Available ABSTRACT Research into memory and epilepsy has focused on measuring problems and exploring causes with limited attention directed at the role of neuropsychological rehabilitation in alleviating post-operative memory difficulties. Objectives To assess the effects of a memory rehabilitation program in patients with left temporal lobe epilepsy following surgery. Methods Twenty-four patients agreed to participate and 18 completed the study; nine received memory rehabilitation while nine had no input and were designated as controls. Verbal learning efficiency, naming abilities, memory subjective ratings, ecological activity measures and a language fMRI paradigm were used as outcome measures. Results Improved verbal learning and naming test performance, increase in memory strategy use and improved self-perception were observed following the rehabilitation. Changes in fMRI activation patterns were seen in the rehabilitation group over the long term. Conclusion The findings support the potential role of a cognitive rehabilitation program following left temporal lobe surgery.

  19. A functional MRI study of language networks in left medial temporal lobe epilepsy

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    Yu Aihong, E-mail: yuaihong163@tom.com [Department of Radiology, the 4th Medical College of Peking University, Beijing Jishuitan Hospital, Beijing 100035 (China); Wang Xiaoyi; Xu Guoqing [Beijing Normal University, State Key Laboratory of Cognitive Neuroscience and Learning, Beijing 100875 (China); Li Yongjie [Beijing Institute of Functional Neurosurgery, Xuanwu Hospital, Capital University of Medical Sciences, Beijing 100053 (China); Qin Wen; Li Kuncheng [Department of Radiology, Xuanwu Hospital, Capital University of Medical Sciences (China); Wang, Yuping [Department of Neurology, Xuanwu Hospital, Capital University of Medical Sciences (China)

    2011-11-15

    Purpose: The purpose of this study was to investigate the abnormality of language networks in left medial temporal lobe epilepsy (MTLE) using fMRI. Materials and methods: Eight patients with left MTLE and 15 healthy subjects were evaluated. An auditory semantic judgment (AJ) paradigm was used. The fMRI data were collected on a 3T MR system and analyzed by AFNI (analysis of functional neuroimages) to generate the activation map. Results: Behavioral data showed that the reaction time of the left MTLE patients was significantly longer than that of controls on the AJ task (t = -3.396, P < 0.05). The left MTLE patients also exhibited diffusively decreased activation in the AJ task. Right hemisphere dominance of Broca's and Wernicke's areas was demonstrated in left MTLE patients. Conclusions: Long-term activation of spikes in left MTLE patients results in language impairment, which is associated with an abnormality of the brain neural network.

  20. Can FDG PET predict verbal specific memory decline after surgery for left temporal lobe epilepsy when MRI is normal?

    International Nuclear Information System (INIS)

    Sagona, J.A.; Rowe, C.C.; Thomas, D.; Dickinson-Rowe, K.L.

    2002-01-01

    Full text: Temporal lobectomy gives excellent control of seizures in over 80% of patients with temporal lobe epilepsy. The left temporal lobe, particularly the left hippocampus, is primarily responsible for verbal memory. In most patients, the hippocampus which lies in the medial temporal lobe is abnormal and can be removed without loss of memory function. However, removal of the left hippocampus when it appears normal on MRI, often causes a significant decline in verbal specific memory (VSM) function. This paper explores the significance of pre-operative FDG-PET asymmetry in temporal lobe metabolism in predicting the VSM outcome after left temporal lobectomy when MRI demonstrates a normal hippocampus. Fifteen patients between 1993 and 2000, underwent left temporal lobectomy including left hippocampal resection, Pre-operatively all patients underwent 1.5T MRI, FDG PET and neuropsychological assessment. Neuropsychological assessment was repeated post-operatively. The left hippocampus was normal on MRI in nine and demonstrated mild T2 signal change without atrophy in six. FDG PET demonstrated temporal lobe hypometabolism in 12 patients. Post-operatively, neuropsychological evaluation documented a decline in verbal specific memory function in six patients, three with normal MRI and three with mild T2 change. We found that all patients with normal FDG PET studies (n=3) demonstrated significant verbal memory deterioration post-operatively. Nine of twelve patients (75%) with left temporal lobe hypometabolism did not show new verbal memory deficits. FDG PET improves the risk stratification for verbal specific memory decline with left temporal lobectomy in patients with normal hippocampi on MRI. Copyright (2002) The Australian and New Zealand Society of Nuclear Medicine Inc

  1. Large-scale brain networks are distinctly affected in right and left mesial temporal lobe epilepsy.

    Science.gov (United States)

    de Campos, Brunno Machado; Coan, Ana Carolina; Lin Yasuda, Clarissa; Casseb, Raphael Fernandes; Cendes, Fernando

    2016-09-01

    Mesial temporal lobe epilepsy (MTLE) with hippocampus sclerosis (HS) is associated with functional and structural alterations extending beyond the temporal regions and abnormal pattern of brain resting state networks (RSNs) connectivity. We hypothesized that the interaction of large-scale RSNs is differently affected in patients with right- and left-MTLE with HS compared to controls. We aimed to determine and characterize these alterations through the analysis of 12 RSNs, functionally parceled in 70 regions of interest (ROIs), from resting-state functional-MRIs of 99 subjects (52 controls, 26 right- and 21 left-MTLE patients with HS). Image preprocessing and statistical analysis were performed using UF(2) C-toolbox, which provided ROI-wise results for intranetwork and internetwork connectivity. Intranetwork abnormalities were observed in the dorsal default mode network (DMN) in both groups of patients and in the posterior salience network in right-MTLE. Both groups showed abnormal correlation between the dorsal-DMN and the posterior salience, as well as between the dorsal-DMN and the executive-control network. Patients with left-MTLE also showed reduced correlation between the dorsal-DMN and visuospatial network and increased correlation between bilateral thalamus and the posterior salience network. The ipsilateral hippocampus stood out as a central area of abnormalities. Alterations on left-MTLE expressed a low cluster coefficient, whereas the altered connections on right-MTLE showed low cluster coefficient in the DMN but high in the posterior salience regions. Both right- and left-MTLE patients with HS have widespread abnormal interactions of large-scale brain networks; however, all parameters evaluated indicate that left-MTLE has a more intricate bihemispheric dysfunction compared to right-MTLE. Hum Brain Mapp 37:3137-3152, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. © 2016 The Authors Human Brain Mapping Published by

  2. Effects of dual pathology on cognitive outcome following left anterior temporal lobectomy for treatment of epilepsy.

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    Prayson, B E; Prayson, R A; Kubu, C S; Bingaman, W; Najm, I M; Busch, R M

    2013-09-01

    The objective of this retrospective study was to determine if dual pathology [DUAL - focal cortical dysplasia (FCD) and mesial temporal sclerosis (MTS)] in patients with left temporal lobe epilepsy is associated with greater risk for cognitive decline following temporal lobectomy than single pathology (MTS only). Sixty-three adults (Mage=36.5years, female: 52.4%) who underwent left anterior temporal lobectomy for treatment of epilepsy (MTS=28; DUAL=35) completed preoperative and postoperative neuropsychological evaluations. The base rate of dual pathology was 55.5%. Repeated measures ANOVAs yielded significant 2-way interactions (group×time) on most measures of language and memory with generally moderate effect sizes. Specifically, patients with MTS only demonstrated postoperative declines, while those with dual pathology remained unchanged or improved. Results suggest that dual pathology may be associated with better cognitive outcome following epilepsy surgery than MTS alone, possibly reflecting limited functionality of the resected tissue or intrahemispheric reorganization of function in the context of a developmental lesion. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. AN INVESTIGATION OF IMPLICIT MEMORY THROUGH LEFT TEMPORAL LOBECTOMY FOR EPILEPSY

    Science.gov (United States)

    Tracy, Joseph I.; Osipowicz, Karol; Godofsky, Samuel; Shah, Atif; Khan, Waseem; Sharan, Ashwini; Sperling, Michael R.

    2012-01-01

    Temporal lobe epilepsy patients have demonstrated a relative preservation in the integrity of implicit memory procedures. We examined performance in a verbal implicit and explicit memory task in left anterior temporal lobectomy patients (LATL) and healthy normal controls (NC) while undergoing fMRI. We hypothesized that despite the relative integrity of implicit memory in both the LATL patients and normal controls, the two groups would show distinct functional neuroanatomic profiles during implicit memory. LATLs and NCs performed Jacoby’s Process Dissociation Process (PDP) procedure during fMRI, requiring completion of word stems based on the previously studied words or new/unseen words. Measures of automaticity and recollection provided uncontaminated indices of implicit and explicit memory, respectively. The behavioral data showed that in the face of temporal lobe pathology implicit memory can be carried out, suggesting implicit verbal memory retrieval is non-mesial temporal in nature. Compared to NCs, the LATL patients showed reliable activation, not deactivation, during implicit (automatic) responding. The regions mediating this response were cortical (left medial frontal and precuneus) and striatal. The active regions in LATL patients have the capacity to implement associative, conditioned responses that might otherwise be carried out by a healthy temporal lobe, suggesting this represented a compensatory activity. Because the precuneus has also been implicated in explicit memory, the data suggests this structure may have a highly flexible functionality, capable of supporting implementation of either explicit memory, or automatic processes such as implicit memory retrieval. Our data suggest that a healthy mesial/anterior temporal lobe may be needed for generating the posterior deactivation perceptual priming response seen in normals. PMID:22981890

  4. EDUCATIONAL PECULIARITIES AND DIFFICULTIES OF CHILDREN WITH LEFT-SIDED LATERALITY: THE TECHNOLOGICAL SOLUTION OF THE PROBLEM

    Directory of Open Access Journals (Sweden)

    Maria Sitnikova

    2011-09-01

    Full Text Available Nowadays there is a significant increase of the incidence of left-handedness and sinistrality among schoolchildren. Theydemonstrate a large number of left-sided motor and sensory preferences which are considered as external markers offunctional hemispheric asymmetry of the brain. The purposes of this study are to investigate gender peculiarities and specificityof age-related dynamics of laterality pattern’s formation in junior schoolchildren and to find out educational peculiarities anddifficulties of left-handed children. The findings show that left-handers differ greatly in their mental development by havingsome peculiarities of intelligence, world’s perception and prevailing thinking strategies, ways of memorization, specificity ofemotional-affective expression. The main problems of left-handed children in school performance are academic failure, lack ofperseverance, anxiety neurosis, and extreme emotional lability. Integrated development of the left hemisphere and the righthemisphere thinking of left-handed schoolchildren is a favorable condition for harmonious personal and intellectualdevelopment and effective mastering of various modules of the school curriculum. The technological solution of the problem ofteaching the children with left-sided laterality is to include in educational programs some special exercises to developimagination, emotional sensitivity, integrity of perception, global view to the problems, creativeness, and original approachesto tasks’ solving. So a complex program for the intensive development of the right hemisphere of children who demonstrateleft-sided laterality to overcome the possible failure at primary school is proposed in this paper.

  5. Incipient preoperative reorganization processes of verbal memory functions in patients with left temporal lobe epilepsy.

    Science.gov (United States)

    Milian, Monika; Zeltner, Lena; Erb, Michael; Klose, Uwe; Wagner, Kathrin; Frings, Lars; Veil, Cornelia; Rona, Sabine; Lerche, Holger; Klamer, Silke

    2015-01-01

    We previously reported nonlinear correlations between verbal episodic memory performance and BOLD signal in memory fMRI in healthy subjects. The purpose of the present study was to examine this observation in patients with left mesial temporal lobe epilepsy (mTLE) who often experience memory decline and need reliable prediction tools before epilepsy surgery with hippocampectomy. Fifteen patients with left mTLE (18-57years, nine females) underwent a verbal memory fMRI paradigm. Correlations between BOLD activity and neuropsychological data were calculated for the i) hippocampus (HC) as well as ii) extrahippocampal mTL structures. Memory performance was systematically associated with activations within the right HC as well as with activations within the left extrahippocampal mTL regions (amygdala and parahippocampal gyrus). As hypothesized, the analyses revealed cubic relationships, with one peak in patients with marginal memory performance and another peak in patients with very good performance. The nonlinear correlations between memory performance and activations might reflect the compensatory recruitment of neural resources to maintain memory performance in patients with ongoing memory deterioration. The present data suggest an already incipient preoperative reorganization process of verbal memory in non-amnesic patients with left mTLE by simultaneously tapping the resources of the right HC and left extrahippocampal mTL regions. Thus, in the preoperative assessment, both neuropsychological performance and memory fMRI should be considered together. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Tempering Proactive Cognitive Control by Transcranial Direct Current Stimulation of the Right (but Not the Left Lateral Prefrontal Cortex

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    Carlos J. Gómez-Ariza

    2017-05-01

    Full Text Available Behavioral and neuroimaging data support the distinction of two different modes of cognitive control: proactive, which involves the active and sustained maintenance of task-relevant information to bias behavior in accordance with internal goals; and reactive, which entails the detection and resolution of interference at the time it occurs. Both control modes may be flexibly deployed depending on a variety of conditions (i.e., age, brain alterations, motivational factors, prior experience. Critically, and in line with specific predictions derived from the dual mechanisms of control account (Braver, 2012, findings from neuroimaging studies indicate that the same lateral prefrontal regions (i.e., left dorsolateral cortex and right inferior frontal junction may implement different control modes on the basis of temporal dynamics of activity, which would be modulated in response to external or internal conditions. In the present study, we aimed to explore whether transcraneal direct current stimulation over either the left dorsolateral prefrontal cortex or the right inferior frontal junction would differentially modulate performance on the AX-CPT, a well-validated task that provides sensitive and reliable behavioral indices of proactive/reactive control. The study comprised six conditions of real stimulation [3 (site: left dorsolateral, right dorsolateral and right inferior frontal junction × 2 (polarity: anodal and cathodal], and one sham condition. The reference electrode was always placed extracephalically. Performance on the AX-CPT was assessed through two blocks of trials. The first block took place while stimulation was being delivered, whereas the second block was administered after stimulation completion. The results indicate that both offline cathodal stimulation of the right dorsolateral prefrontal cortex and online anodal stimulation of the right inferior frontal junction led participants to be much less proactive, with such a dissociation

  7. Temporal Fourier transform of digital angiograms for left ventricular regional wall motion analysis

    International Nuclear Information System (INIS)

    Katayama, Kazuhiro; Guth, B.D.; Widmann, T.F.; Lee, Jong-Dae; Seitelberger, R.; Peterson, K.L.

    1988-01-01

    To determine whether or not the first harmonic of a temporal Fourier transform, applied pixel-by-pixel on time-intensity curves, can detect the subtle wall motion abnormalities due to ischemia, 6 dogs were instrumented with a micromanometer in the left ventricles, a hydraulic cuff occluder around the circumflex coronary artery, and sonomicrometers on the inferior (ischemic) and anterior (non-ischemic) walls. Left ventricular images, obtained after contrast injection via the pulmonary artery, were compared with dimension signals in control and 3 progressive levels of coronary stenosis (Stenosis I, II and III). Normalized, digital functional images (512 x 512 matrix, 256 shades of gray/pixel) were divided into anterior, apical, and inferior areas to acquire regional mean phase (degrees) and amplitude (intensity units) values. After inducing stenosis, phase in ischemic region significantly increased at all 3 levels of stenosis, whereas amplitude significantly decreased at Stenosis II and III. However, amplitude images showed clearly the topographic site of ischemia. There was a progressive increase in phase and decrease in amplitude in ischemic areas as the percent wall thickening (%WTh) fell (phase vs. %WTh: r = -0.55, p < 0.005; amplitude vs. %WTh: r = 0.71, p < 0.001). Heart rate and peak systolic pressure showed no significant changes during stenoses. We conclude that quantitative functional images, generated from a temporal Fourier transform, are sensitive to the detection of left ventricular regional wall motion abnormalities during mild, moderate, and severe degrees of ischemia. (author)

  8. Composing lexical versus functional adjectives: Evidence for uniformity in the left temporal lobe.

    Science.gov (United States)

    Zhang, Linmin; Pylkkänen, Liina

    2018-04-24

    Featural information (e.g., color or shape) allows interlocutors to focus their attention on the specific items under discussion from the vast set of possibilities in the environment. Intriguingly, when they are used to modify and restrict nouns, adjectives can either carry featural information themselves (e.g., green car) or retrieve featural information from the context (e.g., somebody points at a car and claims that she has the same car or a different car). Do the processing of same/different car and green car share neural correlates? For the composition of nouns with feature-carrying adjectives, prior work revealed early compositional effects (roughly 200 ms after noun onset) in the left anterior temporal lobe. However, although we know that such effects do not extend to cases of numeral quantification, which add no conceptual features to the noun (e.g., two boats), we do not know whether they extend to functional adjectives that themselves introduce no features, but instead reference features in the context. To address this question, we measured magnetoencephalography (MEG) during the processing of five types of noun phrases (NPs): same NPs (e.g., same star), different NPs (e.g., different star), color NPs (e.g., green star), comparative NPs (e.g., larger star), and another NPs (e.g., another star). Our main finding was that between 185 to 240 ms after noun onset, same and different NPs patterned with the color NPs in their elicited left temporal lobe activity, and same NPs even trended toward higher amplitudes than the color NPs. This shows that the mechanism driving combinatory effects in the left temporal cortex does not require the input words to directly name conceptual features, as long as the words reference featural information in the context, and that overlapping neural correlates underlie the composition of featural information from both linguistic and nonlinguistic sources.

  9. Ictal postictal and interictal single-photon emission tomography in the lateralization of temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Newton, M.R.; Berkovic, S.F.; Austin, M.C.; Rowe, C.C.; McKay, W.J.; Bladin, P.F.

    1994-01-01

    Single-photon emission tomography (SPET) using radioligands that are fixed on first pass through the cerebral circulation shows distinctive and rapidly changing blood flow patterns accompanying temporal lobe seizures. We sought to determine the optimal time to perform SPET studies for clinical seizure lateralization in temporal lobe epilepsy. Interictal, ictal and postictal SPET scans of 73 consecutively studied patients with unilateral temporal lobe epilepsy were read by three blinded observers to assess the accuracy of lateralization in each condition. The blinded observers correctly identified the side of focus in 97% of ictal studies, 72% of postictal studies and 50% of interictal studies. No incorrect scores were made in the ictal studies, whilst 5% of postictal and 12% of interictal studies were lateralized to the wrong side. Inter-observer agreement was best with the ictal studies. The dramatic perfusion changes of ictal SPET provide consistent, reliable and easily interpretable information that is superior to that provided by interictal and postictal studies. Injection of ligand during seizures is therefore the method of choice for SPET to aid the non-invasive lateralization of temporal seizure foci. (orig.)

  10. Memory outcome following left anterior temporal lobectomy in patients with a failed Wada test.

    Science.gov (United States)

    Rathore, Chaturbhuj; Alexander, Aley; Sarma, P Sankara; Radhakrishnan, Kurupath

    2015-03-01

    This study aimed to compare the memory outcome following left anterior temporal lobectomy (ATL) between patients with a failed Wada test and patients who passed the Wada test. From 1996 to 2002, we performed the Wada test on all patients with unilateral left mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS) and concordant electroclinical data before ATL. We used a 12-item recognition paradigm for memory testing and awarded a score of +1 for each correct response and -0.5 for each incorrect response. No patient was denied surgery on the basis of Wada scores. We assessed cognitive and memory functions using the Wechsler Adult Intelligence Scale and the Wechsler Memory Scale preoperatively and at one year after ATL. We compared the number of patients who showed decline in memory scores, as per the published reliable change indices, between the patients with a failed Wada test and the patients who passed the Wada test. Out of the 116 eligible patients with left MTLE-HS, 88 underwent bilateral Wada test, while 28 underwent ipsilateral Wada test. None of them developed postoperative amnesia. Approximately, one-third of patients with a failed Wada memory test when the failure was defined as a contralateral score of 8, and as an asymmetry score of failed Wada memory test and the group who passed the Wada memory test. The results remained the same when analyses were repeated at various other cutoff points. The patients with left MTLE-HS with concordant electroclinical, MRI, and neuropsychological data should not be denied ATL solely on the basis of Wada memory test results. Copyright © 2015 Elsevier Inc. All rights reserved.

  11. Attention that covers letters is necessary for the left-lateralization of an early print-tuned ERP in Japanese hiragana.

    Science.gov (United States)

    Okumura, Yasuko; Kasai, Tetsuko; Murohashi, Harumitsu

    2015-03-01

    Extensive experience with reading develops expertise in acquiring information from print, and this is reflected in specific enhancement of the left-lateralized N170 component in event-related potentials. The N170 is generally considered to reflect visual/orthographic processing; while modulations of its left-lateralization related to phonological processes have also been indicated. However, in our previous study, N170-like response to Hiragana strings lacked left-lateralization when the stimuli were completely task-irrelevant in rapid-presentation sequences [Okumura et al. (2014). Early print-tuned ERP response with minimal involvement of linguistic processing in Japanese Hiragana strings. Neuroreport 25, 410-414]. This suggests that, despite the highly transparent character-to-syllable correspondence, the phonological mapping of Hiragana strings requires some kind of attention toward print. To verify this notion, the present study examined ERPs under the same experimental condition as in the previous study, except that the task required attention to a stimulus attribute (i.e., color). As a result, Hiragana words and nonwords elicited left-lateralized negative deflection in the occipito-temporal region during 130-170ms post-stimulus in comparison to symbol strings, but only when the print had a narrow intercharacter spacing. Moreover, we observed the enhancement of very early occipital ERP in response to words during 70-100ms. The present results suggest that visual attention plays a role in early print processing, which may contribute to our understanding of the mechanisms that underlie expert as well as impaired reading. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Reading words and other people: A comparison of exception word, familiar face and affect processing in the left and right temporal variants of primary progressive aphasia.

    Science.gov (United States)

    Binney, Richard J; Henry, Maya L; Babiak, Miranda; Pressman, Peter S; Santos-Santos, Miguel A; Narvid, Jared; Mandelli, Maria Luisa; Strain, Paul J; Miller, Bruce L; Rankin, Katherine P; Rosen, Howard J; Gorno-Tempini, Maria Luisa

    2016-09-01

    Semantic variant primary progressive aphasia (svPPA) typically presents with left-hemisphere predominant rostral temporal lobe (rTL) atrophy and the most significant complaints within the language domain. Less frequently, patients present with right-hemisphere predominant temporal atrophy coupled with marked impairments in processing of famous faces and emotions. Few studies have objectively compared these patient groups in both domains and therefore it is unclear to what extent the syndromes overlap. Clinically diagnosed svPPA patients were characterized as left- (n = 21) or right-predominant (n = 12) using imaging and compared along with 14 healthy controls. Regarding language, our primary focus was upon two hallmark features of svPPA; confrontation naming and surface dyslexia. Both groups exhibited naming deficits and surface dyslexia although the impairments were more severe in the left-predominant group. Familiarity judgments on famous faces and affect processing were more profoundly impaired in the right-predominant group. Our findings suggest that the two syndromes overlap significantly but that early cases at the tail ends of the continuum constitute a challenge for current clinical criteria. Correlational neuroimaging analyses implicated a mid portion of the left lateral temporal lobe in exception word reading impairments in line with proposals that this region is an interface between phonology and semantic knowledge. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Lateral chest radiographic findings in lobar collapse of the left lung : the distance between both upper lobe bronchi

    International Nuclear Information System (INIS)

    Chin, G. H.; Sung, D. W.; Yoon, Y.; Kim, H. C.

    1996-01-01

    To evaluate the distance between both upper love bronchi on lateral radiographs and its change in left upper or lower lobe collapse. 144 true lateral radiographs were analyzed on which both upper lobe bronchi were clearly identified. They included 116 normal cases, 11 cases of left upper lobe collapse, 13 of left lower lobe collapse, and 4 cases of left lower lobe lobectomy. Line A was drawn parallel to the vertebral end plate through the upper margin of the lift upper lobe bronchus. Line B was drawn parallel to line A through the upper margin of the right upper love bronchus. The shortest distance between line A and line B was measured as the distance between both upper lobe bronchi. In normal cases, the mean value of the distance was 2.19 cm ± S.D. 0.37 cm on right and on right and 2.16 cm ± S.D. 0.40 cm on left lateral radiographs ; these results were not significantly different(P=0.79). In cases of collapse, the mean value of the distance was 0.43 cm ± S.D. 0.99 cm in upper lobe collapse and 3.56 cm ± S.D. 0.72 cm in lower lobe collapse, results which were significantly different from those of normal cases(p<0.01). In eight cases(73%) of left upper lobe collapse, the distance was less than 1 cm and in 10 cases(77%) of left lower lobe collapse, the distance was more than 3 cm. The distance between both upper lobe bronchi varies markedly in case of lobar collapse. A distance of less than 1 cm suggests collapse of the left upper lobe and a distance more than 3 cm suggests collapse of the left lower lobe

  14. Selective activation around the left occipito-temporal sulcus for words relative to pictures: Individual variability or false positives?

    NARCIS (Netherlands)

    Wright, Nicholas D.; Mechelli, Andrea; Noppeney, Uta; Veltman, Dick J.; Rombouts, Serge A. R. B.; Glensman, Janice; Haynes, John-Dylan; Price, Cathy J.

    2008-01-01

    We used high-resolution fMRI to investigate claims that learning to read r !sults in greater left occipito-temporal (OT) activation for written words relative to pictures of objects. In tl e first experiment, 9/16 subjects performing a one-back task showed activation in >= 1 left OT voxel for word:

  15. Focal epileptic seizures with secondary generalization in cortical atrophy and gliosis dysplasia in the left temporal lobe and hemimegalencephaly in the left occipital lobe

    International Nuclear Information System (INIS)

    Manchev, I.; Mancheva-Ganeva, V.; Manolova, T.; Manchev, L.

    2016-01-01

    It is a case of an eight-year-old patient with cortical dysplasia and gliosis in the left temporal lobe clinically manifested with focal epileptic seizures with secondary generalization. Signs of mental retardation and a number of somatic complications - diabetes, etc., were found. The complex therapy with anticonvulsant medications, immunovenin, plasmaphoresis and anti-diabetic drugs was partially effective

  16. Genetic underpinnings of left superior temporal gyrus thickness in patients with schizophrenia.

    Science.gov (United States)

    Wolthusen, Rick P F; Hass, Johanna; Walton, Esther; Turner, Jessica A; Rössner, Veit; Sponheim, Scott R; Ho, Beng-Choon; Holt, Daphne J; Gollub, Randy L; Calhoun, Vince; Ehrlich, Stefan

    2015-08-07

    Schizophrenia is a highly disabling psychiatric disorder with a heterogeneous phenotypic appearance. We aimed to further the understanding of some of the underlying genetics of schizophrenia, using left superior temporal gyrus (STG) grey matter thickness reduction as an endophenoptype in a genome-wide association (GWA) study. Structural magnetic resonance imaging (MRI) and genetic data of the Mind Clinical Imaging Consortium (MCIC) study of schizophrenia were used to analyse the interaction effects between 1,067,955 single nucleotide polymorphisms (SNPs) and disease status on left STG thickness in 126 healthy controls and 113 patients with schizophrenia. We next used a pathway approach to detect underlying pathophysiological pathways that may be related to schizophrenia. No SNP by diagnosis interaction effect reached genome-wide significance (5 × 10 -8 ) in our GWA study, but 10 SNPs reached P-values less than 10 -6 . The most prominent pathways included those involved in insulin, calcium, PI3K-Akt and MAPK signalling. Our strongest findings in the GWA study and pathway analysis point towards an involvement of glucose metabolism in left STG thickness reduction in patients with schizophrenia only. These results are in line with recently published studies, which showed an increased prevalence of psychosis among patients with metabolic syndrome-related illnesses including diabetes.

  17. Anterior & lateral extension of optic radiation & safety of amygdalohippocampectomy through middle temporal gyrus: a cadaveric study of 11 cerebral hemispheres.

    Science.gov (United States)

    Chowdhury, F H; Khan, A H

    2010-01-01

    This is a cadaveric anatomical study on the localization of the optic radiation within the temporal lobe and to find whether surgical intervention to the temporal lobe, especially amygdalohippocampectomy, can damage the optic radiation or not. 11 cadaveric cerebral hemispheres were used for the study. A 2 cm long antero-posterior incision was done with a sharp knife, on middle temporal gyrus, starting 3 cm posterior to temporal pole. The incision was deepened perpendicular to surface of the gyrus to reach the temporal horn. The optic radiation was dissected under operating microscope using Klinger's fiber dissection technique and measurements were taken to define the anterior and lateral extension of optic radiation. The optic radiation in each hemispehere was inspected for any incision related damage. No damage to the optic radiation was found, caused by the 2 cm long anterior-posterior incision on middle temporal gyrus 3 cm posterior to temporal pole. Most anterior 9mm (8-10mm) of the Meyer loop was completely on the roof and there was no extension over lateral wall of the temporal horn. In next posterior 17.5mm (16-20 mm) it extended over lateral wall of temporal horn with gradual progression. The most anterior extension of optic radiation was 26mm (23-31mm) posterior to temporal pole. Amygdalohippocampectomy through a 2 cm long horizontal incision on the middle temporal gyrus, starting 3 cm posterior to the temporal pole, to enter into the temporal horn through the lower aspect of the lateral wall is unlikely to cause damage to the Meyer's loop. Any entry from the superior aspect of the temporal horn and any temporal lobectomy inclusive of the superior temporal gyrus to enter the temporal horn is likely to cause Meyer's loop injury. The findings support the fact that the more inferior the surgical trajectory to the temporal horn of the lateral ventricle, the lover is the risk of visual field damage.

  18. Embryonic left-right separation mechanism allows confinement of mutation-induced phenotypes to one lateral body half of bilaterians.

    Science.gov (United States)

    Ma, Kun

    2013-12-01

    A fundamental question in developmental biology is how a chimeric animal such as a bilateral gynandromorphic animal can have different phenotypes confined to different lateral body halves, and how mutation-induced phenotypes, such as genetic diseases, can be confined to one lateral body half in patients. Here, I propose that embryos of many, if not all, bilaterian animals are divided into left and right halves at a very early stage (which may vary among different types of animals), after which the descendants of the left-sided and right-sided cells will almost exclusively remain on their original sides, respectively, throughout the remaining development. This embryonic left-right separation mechanism allows (1) mutations and the mutation-induced phenotypes to be strictly confined to one lateral body half in animals and humans; (2) mothers with bilateral hereditary primary breast cancer to transmit their disease to their offspring at twofold of the rate compared to mothers with unilateral hereditary breast cancer; and (3) a mosaic embryo carrying genetic or epigenetic mutations to develop into either an individual with the mutation-induced phenotype confined unilaterally, or a pair of twins displaying complete, partial, or mirror-image discordance for the phenotype. Further, this left-right separation mechanism predicts that the two lateral halves of a patient carrying a unilateral genetic disease can each serve as a case and an internal control, respectively, for genetic and epigenetic comparative studies to identify the disease causations. © 2013 Wiley Periodicals, Inc.

  19. Temporal Lobe Encephalocele in the Lateral Recess of the Sphenoid Sinus Presenting with Intraventricular Tension Pneumocephalus

    OpenAIRE

    Ohkawa, Toshika; Nakao, Naoyuki; Uematsu, Yuji; Itakura, Toru

    2010-01-01

    A basal encephalocele often shows an insidious clinical course. Only two cases of temporal lobe encephalocele accompanied with tension pneumocephalus have previously been reported. In this paper, we describe a case of lateral sphenoid sinus encephalocele presenting with intraventricular tension pneumocephalus. A 54-year-old man was referred to our institution presenting with intraventricular tension pneumocephalus. He had undergone ventriculoperitoneal shunt placement for postmeningitis hydro...

  20. Language development at 2 years is correlated to brain microstructure in the left superior temporal gyrus at term equivalent age: a diffusion tensor imaging study.

    Science.gov (United States)

    Aeby, Alec; De Tiège, Xavier; Creuzil, Marylise; David, Philippe; Balériaux, Danielle; Van Overmeire, Bart; Metens, Thierry; Van Bogaert, Patrick

    2013-09-01

    This study aims at testing the hypothesis that neurodevelopmental abilities at age 2 years are related with local brain microstructure of preterm infants at term equivalent age. Forty-one preterm infants underwent brain MRI with diffusion tensor imaging sequences to measure mean diffusivity (MD), fractional anisotropy (FA), longitudinal and transverse diffusivity (λ// and λ[perpendicular]) at term equivalent age. Neurodevelopment was assessed at 2 years corrected age using the Bayley III scale. A voxel-based analysis approach, statistical parametric mapping (SPM8), was used to correlate changes of the Bayley III scores with the regional distribution of MD, FA, λ// and λ[perpendicular]. We found that language abilities are negatively correlated to MD, λ// and λ[perpendicular] in the left superior temporal gyrus in preterm infants. These findings suggest that higher MD, λ// and λ[perpendicular] values at term-equivalent age in the left superior temporal gyrus are associated with poorer language scores in later childhood. Consequently, it highlights the key role of the left superior temporal gyrus for the development of language abilities in children. Further studies are needed to assess on an individual basis and on the long term the prognostic value of brain DTI at term equivalent age for the development of language. Copyright © 2013 Elsevier Inc. All rights reserved.

  1. BOLD response to motion verbs in left posterior middle temporal gyrus during story comprehension

    DEFF Research Database (Denmark)

    Wallentin, Mikkel; Nielsen, Andreas Højlund; Vuust, Peter

    2011-01-01

    A primary focus within neuroimaging research on language comprehension is on the distribution of semantic knowledge in the brain. Studies have shown that the left posterior middle temporal gyrus (LPMT), a region just anterior to area MT/V5, is important for the processing of complex action...... knowledge. It has also been found that motion verbs cause activation in LPMT. In this experiment we investigated whether this effect could be replicated in a setting resembling real life language comprehension, i.e. without any overt behavioral task during passive listening to a story. During f......, clauses containing motion verbs were accompanied by a robust activation of LPMT with no other significant effects, consistent with the hypothesis that this brain region is important for processing motion knowledge, even during naturalistic language comprehension conditions....

  2. Graded representations of emotional expressions in the left superior temporal sulcus

    Directory of Open Access Journals (Sweden)

    Christopher P Said

    2010-03-01

    Full Text Available Perceptual categorization is a fundamental cognitive process that gives meaning to an often graded sensory environment. Previous research has subdivided the visual pathway into posterior regions that processes the physical properties of a stimulus, and frontal regions that process more abstract properties such as category information. The superior temporal sulcus (STS is known to be involved in face and emotion perception, but the nature of its processing remains unknown. Here, we used targeted fMRI measurements of the STS to investigate whether its representations of facial expressions are categorical or noncategorical. Multivoxel pattern analysis showed that even though subjects were performing a categorization task, the left STS contained graded, noncategorical representations. In the right STS, representations showed evidence for both stimulus-related gradations and a categorical boundary.

  3. Material specific lateralization of medial temporal lobe function: An fMRI investigation.

    Science.gov (United States)

    Dalton, Marshall A; Hornberger, Michael; Piguet, Olivier

    2016-03-01

    The theory of material specific lateralization of memory function posits that left and right MTL regions are asymmetrically involved in mnemonic processing of verbal and nonverbal material respectively. Lesion and functional imaging (fMRI) studies provide robust evidence for a left MTL asymmetry in the verbal memory domain. Evidence for a right MTL/nonverbal asymmetry is not as robust. A handful of fMRI studies have investigated this issue but have generally utilised nonverbal stimuli which are amenable to semantic elaboration. This fMRI study aimed to investigate the neural correlates of recognition memory processing in 20 healthy young adults (mean age = 26 years) for verbal stimuli and nonverbal stimuli that were specifically designed to minimize verbalisation. Analyses revealed that the neural correlates of recognition memory processing for verbal and nonverbal stimuli were differentiable and asymmetrically recruited the left and right MTL respectively. The right perirhinal cortex and hippocampus were preferentially involved in successful recognition memory of items devoid of semantic information. In contrast, the left anterior hippocampus was preferentially involved in successful recognition memory of stimuli which contained semantic meaning. These results suggest that the left MTL is preferentially involved in mnemonic processing of verbal/semantic information. In contrast, the right MTL is preferentially involved in visual/non-semantic mnemonic processing. We propose that during development, the left MTL becomes specialised for verbal mnemonic processing due to its proximity with left lateralised cortical language processing areas while visual/non-semantic mnemonic processing gets 'crowded out' to become predominantly, but not completely, the domain of the right MTL. © 2015 Wiley Periodicals, Inc.

  4. Spatio-temporal dynamics and laterality effects of face inversion, feature presence and configuration, and face outline

    Directory of Open Access Journals (Sweden)

    Ksenija eMarinkovic

    2014-11-01

    Full Text Available Although a crucial role of the fusiform gyrus in face processing has been demonstrated with a variety of methods, converging evidence suggests that face processing involves an interactive and overlapping processing cascade in distributed brain areas. Here we examine the spatio-temporal stages and their functional tuning to face inversion, presence and configuration of inner features, and face contour in healthy subjects during passive viewing. Anatomically-constrained magnetoencephalography (aMEG combines high-density whole-head MEG recordings and distributed source modeling with high-resolution structural MRI. Each person's reconstructed cortical surface served to constrain noise-normalized minimum norm inverse source estimates. The earliest activity was estimated to the occipital cortex at ~100 ms after stimulus onset and was sensitive to an initial coarse level visual analysis. Activity in the right-lateralized ventral temporal area (inclusive of the fusiform gyrus peaked at ~160ms and was largest to inverted faces. Images containing facial features in the veridical and rearranged configuration irrespective of the facial outline elicited intermediate level activity. The M160 stage may provide structural representations necessary for downstream distributed areas to process identity and emotional expression. However, inverted faces additionally engaged the left ventral temporal area at ~180 ms and were uniquely subserved by bilateral processing. This observation is consistent with the dual route model and spared processing of inverted faces in prosopagnosia. The subsequent deflection, peaking at ~240ms in the anterior temporal areas bilaterally, was largest to normal, upright faces. It may reflect initial engagement of the distributed network subserving individuation and familiarity. These results support dynamic models suggesting that processing of unfamiliar faces in the absence of a cognitive task is subserved by a distributed and

  5. Morphometry of Left Frontal and Temporal Poles Predicts Analogical Reasoning Abilities.

    Science.gov (United States)

    Aichelburg, Clarisse; Urbanski, Marika; Thiebaut de Schotten, Michel; Humbert, Frederic; Levy, Richard; Volle, Emmanuelle

    2016-03-01

    Analogical reasoning is critical for making inferences and adapting to novelty. It can be studied experimentally using tasks that require creating similarities between situations or concepts, i.e., when their constituent elements share a similar organization or structure. Brain correlates of analogical reasoning have mostly been explored using functional imaging that has highlighted the involvement of the left rostrolateral prefrontal cortex (rlPFC) in healthy subjects. However, whether inter-individual variability in analogical reasoning ability in a healthy adult population is related to differences in brain architecture is unknown. We investigated this question by employing linear regression models of performance in analogy tasks and voxel-based morphometry in 54 healthy subjects. Our results revealed that the ability to reason by analogy was associated with structural variability in the left rlPFC and the anterior part of the inferolateral temporal cortex. Tractography of diffusion-weighted images suggested that these 2 regions have a different set of connections but may exchange information via the arcuate fasciculus. These results suggest that enhanced integrative and semantic abilities supported by structural variation in these areas (or their connectivity) may lead to more efficient analogical reasoning. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  6. Effect of invasive EEG monitoring on cognitive outcome after left temporal lobe epilepsy surgery.

    Science.gov (United States)

    Busch, Robyn M; Love, Thomas E; Jehi, Lara E; Ferguson, Lisa; Yardi, Ruta; Najm, Imad; Bingaman, William; Gonzalez-Martinez, Jorge

    2015-10-27

    The objective of this cohort study was to compare neuropsychological outcomes following left temporal lobe resection (TLR) in patients with epilepsy who had or had not undergone prior invasive monitoring. Data were obtained from an institutional review board-approved, neuropsychology registry for patients who underwent epilepsy surgery at Cleveland Clinic between 1997 and 2013. A total of 176 patients (45 with and 131 without invasive EEG) met inclusion criteria. Primary outcome measures were verbal memory and language scores. Other cognitive outcomes were also examined. Outcomes were assessed using difference in scores from before to after surgery and by presence/absence of clinically meaningful decline using reliable change indices (RCIs). Effect of invasive EEG on cognitive outcomes was estimated using weighting and propensity score adjustment to account for differences in baseline characteristics. Linear and logistic regression models compared surgical groups on all cognitive outcomes. Patients with invasive monitoring showed greater declines in confrontation naming; however, when RCIs were used to assess clinically meaningful change, there was no significant treatment effect on naming performance. No difference in verbal memory was observed, regardless of how the outcome was measured. In secondary outcomes, patients with invasive monitoring showed greater declines in working memory, which were no longer apparent using RCIs to define change. There were no outcome differences on other cognitive measures. Results suggest that invasive EEG monitoring conducted prior to left TLR is not associated with greater cognitive morbidity than left TLR alone. This information is important when counseling patients regarding cognitive risks associated with this elective surgery. © 2015 American Academy of Neurology.

  7. ERP measures of partial semantic knowledge: left temporal indices of skill differences and lexical quality.

    Science.gov (United States)

    Frishkoff, Gwen A; Perfetti, Charles A; Westbury, Chris

    2009-01-01

    This study examines the sensitivity of early event-related potentials (ERPs) to degrees of word semantic knowledge. Participants with strong, average, or weak vocabulary skills made speeded lexical decisions to letter strings. To represent the full spectrum of word knowledge among adult native-English speakers, we used rare words that were orthographically matched with more familiar words and with pseudowords. Since the lexical decision could not reliably be made on the basis of word form, subjects were obliged to use semantic knowledge to perform the task. A d' analysis suggested that high-skilled subjects adopted a more conservative strategy in response to rare versus more familiar words. Moreover, the high-skilled participants showed a trend towards an enhanced "N2c" to rare words, and a similar posterior temporal effect reached significance approximately 650 ms. Generators for these effects were localized to left temporal cortex. We discuss implications of these results for word learning and for theories of lexical semantic access.

  8. Thirty Years Later: Evolution of Treatment for Acute Left Main Coronary Artery Occlusion

    Directory of Open Access Journals (Sweden)

    Moshe Y. Flugelman

    2016-01-01

    Full Text Available Acute occlusion of left main coronary artery is a catastrophic event. We describe two patients with acute occlusion of the left main coronary artery treated thirty years apart. The first patient was treated in 1982 and survived the event without revascularization but developed severe heart failure. His survival was so unusual that it merited a case report at that time. The second patient was treated at the end of 2015. Early revascularization resulted in myocardial reperfusion and near normal left ventricular function. These patients exemplify the progress in therapeutic cardiology over the last 30 years.

  9. Insights into Intrinsic Brain Networks based on Graph Theory and PET in right- compared to left-sided Temporal Lobe Epilepsy.

    Science.gov (United States)

    Vanicek, Thomas; Hahn, Andreas; Traub-Weidinger, Tatjana; Hilger, Eva; Spies, Marie; Wadsak, Wolfgang; Lanzenberger, Rupert; Pataraia, Ekaterina; Asenbaum-Nan, Susanne

    2016-06-28

    The human brain exhibits marked hemispheric differences, though it is not fully understood to what extent lateralization of the epileptic focus is relevant. Preoperative [(18)F]FDG-PET depicts lateralization of seizure focus in patients with temporal lobe epilepsy and reveals dysfunctional metabolic brain connectivity. The aim of the present study was to compare metabolic connectivity, inferred from inter-regional [(18)F]FDG PET uptake correlations, in right-sided (RTLE; n = 30) and left-sided TLE (LTLE; n = 32) with healthy controls (HC; n = 31) using graph theory based network analysis. Comparing LTLE and RTLE and patient groups separately to HC, we observed higher lobar connectivity weights in RTLE compared to LTLE for connections of the temporal and the parietal lobe of the contralateral hemisphere (CH). Moreover, especially in RTLE compared to LTLE higher local efficiency were found in the temporal cortices and other brain regions of the CH. The results of this investigation implicate altered metabolic networks in patients with TLE specific to the lateralization of seizure focus, and describe compensatory mechanisms especially in the CH of patients with RTLE. We propose that graph theoretical analysis of metabolic connectivity using [(18)F]FDG-PET offers an important additional modality to explore brain networks.

  10. Reduced parahippocampal and lateral temporal GABAA-[11C]flumazenil binding in major depression: preliminary results

    International Nuclear Information System (INIS)

    Klumpers, Ursula M.H.; Veltman, Dick J.; Drent, Madeleine L.; Boellaard, Ronald; Lammertsma, Adriaan A.; Comans, Emile F.I.; Meynen, Gerben; Hoogendijk, Witte J.G.

    2010-01-01

    Major depressive disorder (MDD) has been related to both a dysfunctional γ-amino butyric acid (GABA) system and to hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA). Although GABA has been suggested to inhibit HPA axis activity, their relationship has never been studied at the level of the central GABA A -benzodiazepine receptor in depressed patients or in relation to antidepressant treatment. Eleven depressed outpatients were compared, before and after treatment with citalopram, with nine age-matched healthy controls. The subjects were scanned using the positron emission tomography (PET) tracer [ 11 C]flumazenil ([ 11 C]FMZ). Parametric voxel-by-voxel Logan plots were compared with methods based on regions of interest (ROI), to provide volume of distribution (V T ) and binding potential (BP ND ) values. Plasma GABA levels were determined and a dexamethasone-corticotropin releasing hormone (DEX-CRH) test was performed. In MDD, parametric voxel-by-voxel Logan plots showed bilateral reduced [ 11 C]FMZ binding in the parahippocampal gyrus and right lateral superior temporal gyrus (p uncorrected ≤0.001). In the temporal area, [ 11 C]FMZ binding showed a strong inverse correlation with HPA axis activity. Plasma GABA did not discriminate MDD from controls, but correlated inversely with [ 11 C]FMZ binding in the right insula. Following treatment with citalopram, voxel-based analysis revealed reduced binding in the right lateral temporal gyrus and dorsolateral prefrontal cortex. The bilateral reduction in limbic parahippocampal and right temporal [ 11 C]FMZ binding found in MDD indicates decreased GABA A -benzodiazepine receptor complex affinity and/or number. The inverse relationship between GABA A binding in the temporal lobe and HPA axis activity, suggests that HPA axis hyperactivity is partly due to reduced GABA-ergic inhibition. (orig.)

  11. The cognitive profile of occipital lobe epilepsy and the selective association of left temporal lobe hypometabolism with verbal memory impairment.

    Science.gov (United States)

    Knopman, Alex A; Wong, Chong H; Stevenson, Richard J; Homewood, Judi; Mohamed, Armin; Somerville, Ernest; Eberl, Stefan; Wen, Lingfeng; Fulham, Michael; Bleasel, Andrew F

    2014-08-01

    We investigated the cognitive profile of structural occipital lobe epilepsy (OLE) and whether verbal memory impairment is selectively associated with left temporal lobe hypometabolism on [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET). Nine patients with OLE, ages 8-29 years, completed presurgical neuropsychological assessment. Composite measures were calculated for intelligence quotient (IQ), speed, attention, verbal memory, nonverbal memory, and executive functioning. In addition, the Wisconsin Card Sorting Test (WCST) was used as a specific measure of frontal lobe functioning. Presurgical FDG-PET was analyzed with statistical parametric mapping in 8 patients relative to 16 healthy volunteers. Mild impairments were evident for IQ, speed, attention, and executive functioning. Four patients demonstrated moderate or severe verbal memory impairment. Temporal lobe hypometabolism was found in seven of eight patients. Poorer verbal memory was associated with left temporal lobe hypometabolism (p = 0.002), which was stronger (p = 0.03 and p = 0.005, respectively) than the association of left temporal lobe hypometabolism with executive functioning or with performance on the WCST. OLE is associated with widespread cognitive comorbidity, suggesting cortical dysfunction beyond the occipital lobe. Verbal memory impairment is selectively associated with left temporal lobe hypometabolism in OLE, supporting a link between neuropsychological dysfunction and remote hypometabolism in focal epilepsy. Wiley Periodicals, Inc. © 2014 International League Against Epilepsy.

  12. Transcranial Magnetic Stimulation over Left Inferior Frontal and Posterior Temporal Cortex Disrupts Gesture-Speech Integration.

    Science.gov (United States)

    Zhao, Wanying; Riggs, Kevin; Schindler, Igor; Holle, Henning

    2018-02-21

    Language and action naturally occur together in the form of cospeech gestures, and there is now convincing evidence that listeners display a strong tendency to integrate semantic information from both domains during comprehension. A contentious question, however, has been which brain areas are causally involved in this integration process. In previous neuroimaging studies, left inferior frontal gyrus (IFG) and posterior middle temporal gyrus (pMTG) have emerged as candidate areas; however, it is currently not clear whether these areas are causally or merely epiphenomenally involved in gesture-speech integration. In the present series of experiments, we directly tested for a potential critical role of IFG and pMTG by observing the effect of disrupting activity in these areas using transcranial magnetic stimulation in a mixed gender sample of healthy human volunteers. The outcome measure was performance on a Stroop-like gesture task (Kelly et al., 2010a), which provides a behavioral index of gesture-speech integration. Our results provide clear evidence that disrupting activity in IFG and pMTG selectively impairs gesture-speech integration, suggesting that both areas are causally involved in the process. These findings are consistent with the idea that these areas play a joint role in gesture-speech integration, with IFG regulating strategic semantic access via top-down signals acting upon temporal storage areas. SIGNIFICANCE STATEMENT Previous neuroimaging studies suggest an involvement of inferior frontal gyrus and posterior middle temporal gyrus in gesture-speech integration, but findings have been mixed and due to methodological constraints did not allow inferences of causality. By adopting a virtual lesion approach involving transcranial magnetic stimulation, the present study provides clear evidence that both areas are causally involved in combining semantic information arising from gesture and speech. These findings support the view that, rather than being

  13. [An autopsied case of dominantly affecting upper motor neuron with atrophy of the frontal and temporal lobes--with special reference to primary lateral sclerosis].

    Science.gov (United States)

    Konagaya, M; Sakai, M; Iida, M; Hashizume, Y

    1995-04-01

    In this paper, the autopsy findings of a 78-year-old man mimicking primary lateral sclerosis (PLS) are reported. His clinical symptoms were slowly progressive spasticity, pseudobulbar palsy and character change. He died of sepsis 32 months after protracting the disease. The autopsy revealed severe atrophy of the frontal and temporal lobes. The histological findings were severe neuronal loss with gliosis in the precentral gyrus and left temporal lobe tip, loss of Betz cell, prominent demyelination throughout of the corticospinal tract, axonal swelling in the cerebral peduncule, severe degeneration of the amygdala, mild degeneration of the Ammon horn, normal substantia nigra, a few neuronal cells with central chromatolysis in the facial nerve nucleus and very mild neuronal cell loss in the spinal anterior horn. The anterior horn cell only occasionally demonstrated Bunina body by H & E and cystatin-C stainings, as well as, skein-like inclusion by ubiquitin staining. Thus, this is a case of uncommon amyotrophic lateral sclerosis (ALS) dominantly affecting the upper motor neuron including the motor cortex and temporal limbic system. In analysis of nine cases of putative primary lateral sclerosis in the literature, six cases showed loss of Betz cell in the precentral gyrus, and four cases very mild involvement of the lower motor neuron such as central chromatolysis and eosinophilic inclusion body. Degeneration of the limbic system was observed in two cases. We indicated a possible subgroup with concomitant involvement in the motor cortex and temporal lobe in motor neuron disease dominantly affecting the upper motor neuron.

  14. Increased spatial granularity of left brain activation and unique age/gender signatures: a 4D frequency domain approach to cerebral lateralization at rest.

    Science.gov (United States)

    Agcaoglu, O; Miller, R; Mayer, A R; Hugdahl, K; Calhoun, V D

    2016-12-01

    Cerebral lateralization is a well-studied topic. However, most of the research to date in functional magnetic resonance imaging (fMRI) has been carried out on hemodynamic fluctuations of voxels, networks, or regions of interest (ROIs). For example, cerebral differences can be revealed by comparing the temporal activation of an ROI in one hemisphere with the corresponding homotopic region in the other hemisphere. While this approach can reveal significant information about cerebral organization, it does not provide information about the full spatiotemporal organization of the hemispheres. The cerebral differences revealed in literature suggest that hemispheres have different spatiotemporal organization in the resting state. In this study, we evaluate cerebral lateralization in the 4D spatiotemporal frequency domain to compare the hemispheres in the context of general activation patterns at different spatial and temporal scales. We use a gender-balanced resting fMRI dataset comprising over 600 healthy subjects ranging in age from 12 to 71, that have previously been studied with a network specific voxel-wise and global analysis of lateralization (Agcaoglu, et al. NeuroImage, 2014). Our analysis elucidates significant differences in the spatiotemporal organization of brain activity between hemispheres, and generally more spatiotemporal fluctuation in the left hemisphere especially in the high spatial frequency bands, and more power in the right hemisphere in the low and middle spatial frequencies. Importantly, the identified effects are not visible in the context of a typical assessment of voxelwise, regional, or even global laterality, thus our study highlights the value of 4D spatiotemporal frequency domain analyses as a complementary and powerful tool for studying brain function.

  15. Dissociating Effects of Scrambling and Topicalization within the Left Frontal and Temporal Language Areas: An fMRI Study in Kaqchikel Maya.

    Science.gov (United States)

    Ohta, Shinri; Koizumi, Masatoshi; Sakai, Kuniyoshi L

    2017-01-01

    Some natural languages grammatically allow different types of changing word orders, such as object scrambling and topicalization. Scrambling and topicalization are more related to syntax and semantics/phonology, respectively. Here we hypothesized that scrambling should activate the left frontal regions, while topicalization would affect the bilateral temporal regions. To examine such distinct effects in our functional magnetic resonance imaging study, we targeted the Kaqchikel Maya language, a Mayan language spoken in Guatemala. In Kaqchikel, the syntactically canonical word order is verb-object-subject (VOS), but at least three non-canonical word orders (i.e., SVO, VSO, and OVS) are also grammatically allowed. We used a sentence-picture matching task, in which the participants listened to a short Kaqchikel sentence and judged whether a picture matched the meaning of the sentence. The advantage of applying this experimental paradigm to an understudied language such as Kaqchikel is that it will allow us to validate the universality of linguistic computation in the brain. We found that the conditions with scrambled sentences [+scrambling] elicited significant activation in the left inferior frontal gyrus and lateral premotor cortex, both of which have been proposed as grammar centers, indicating the effects of syntactic loads. In contrast, the conditions without topicalization [-topicalization] resulted in significant activation in bilateral Heschl's gyrus and superior temporal gyrus, demonstrating that the syntactic and phonological processes were clearly dissociated within the language areas. Moreover, the pre-supplementary motor area and left superior/middle temporal gyri were activated under relatively demanding conditions, suggesting their supportive roles in syntactic or semantic processing. To exclude any semantic/phonological effects of the object-subject word orders, we performed direct comparisons while making the factor of topicalization constant, and

  16. Cerebral lateralization for the processing of spatial coordinates and categories in left-and right-handers.

    Science.gov (United States)

    LAENG, B; PETERS, M

    1995-04-01

    Subjects judged whether a tachistoscopially lateralized drawing was identical or different to a drawing seen immediately before in free vision. The drawings depicted natural objects (e.g. animals). On half of the trials the tachistoscopic drawing presented the same objects but either the categorical or the coordinate spatial relations (according to Kosslyn's definitions [23]) between the objects were transformed. In the first experiment 38 right-handed subjects (half males and half females) were tested. Categorical judgements were faster when the match drawing appeared in the right visual field, whereas coordinate judgements were faster when the match drawing appeared in the left visual field. In the second experiment 26 right-handed and 40 left-handed subjects participated. Almost all the subjects were female. Right-handed subjects replicated the findings of the subjects in the first experiment. However, the LHs did not show any difference in response times between spatial conditions and visual fields. These findings support Kosslyn's hypothesis that the left and right hemispheres are specialized respectively for processing categorical and coordinate spatial relations. Moreover, they also suggest that this lateralization pattern is not typical of left-handers.

  17. Selective Activation Around the Left Occipito-Temporal Sulcus for Words Relative to Pictures: Individual Variability or False Positives?

    OpenAIRE

    Wright, Nicholas D; Mechelli, Andrea; Noppeney, Uta; Veltman, Dick J; Rombouts, Serge ARB; Glensman, Janice; Haynes, John-Dylan; Price, Cathy J

    2007-01-01

    We used high-resolution fMRI to investigate claims that learning to read results in greater left occipito-temporal (OT) activation for written words relative to pictures of objects. In the first experiment, 9/16 subjects performing a one-back task showed activation in ?1 left OT voxel for words relative to pictures (P < 0.05 uncorrected). In a second experiment, another 9/15 subjects performing a semantic decision task activated ?1 left OT voxel for words relative to pictures. However, at thi...

  18. Differentiation of cryptogenic lateral from mesial temporal lobe epilepsy using regional asymmetric index of F-18-FDG PET

    International Nuclear Information System (INIS)

    Song, H. C.; Lee, D. S.; Lee, S. K.; Jeong, J. M.; Jeong, Z. K.; Lee, M. C.; Ko, C. S.

    1997-01-01

    We tried to find the possibility of utilization of F-18-FDG PET to differentiate lateral (neocortical) from mesial temporal lobe epilepsy(TLE) if we adopted quantitative comparison of regional metabolic activities using asymmetric index. We studied 22 pathologically proven mesial TLE(group C in Figure), and 27 lateral TLE patients. Lateral TLE patients were normal on MR(cryptogenic: 15; group A) or had structural lesions (12: group B). Asymmetric index (AI) was calculated as (ipsilateral -contralateral) / (ipsilateral + contralateral ) x 200. AI of medial lobe of cryptogenic lateral TLE was not decreased (-4.66.2, > 0.05) and AI of medial lobe of cryptogenic lateral TLE was not decreased (-4.66.2, >0.05) and AI of lateral lobe was decreased (-13.68.9). AI of medial and lateral lobes of mesial TLE was decreased (-3.44.7 and -16.58.9, respectively). AI of medial lobe of lesional lateral TLE was -7.39.1 (p<0.05 compared with mesial TEL). It was evident that lateral lobe of lesional lateral TLE had metabolic defect or decrease (AI: -21.410.4). While we could not find difference of metabolic activity in lateral temporal lobes between cryptogenic lateral TLE and mesial TLE patients, the difference of metabolic activity was significant in medial temporal lobes which was revealed by AI quantitation. An AI value larger than -10 (cutoff: AI) predicted positively for lateral TLE(PPV:80%) and negatively for mesial TLE(NPV:77%). Asymmetry of metabolic activity in medial and not in lateral lobe of temporal lobe could give hints about whether the epileptogenic zones were mesial or lateral

  19. Right-to-left-shunt detected by c-TCD using the orbital window in comparison with temporal bone windows.

    Science.gov (United States)

    Kobayashi, Kazuto; Kimura, Kazumi; Iguchi, Yasuyuki; Sakai, Kenichirou; Aoki, Junya; Iwanaga, Takeshi; Shibazaki, Kensaku

    2012-01-01

    There have been some reports on right-to-left shunt as a cause of cryptogenic stroke. Although contrast transcranial Doppler (c-TCD) can detect RLS, an insufficient temporal window has occasionally restricted its applicability. Thus, we compared the rates of detecting RLS among temporal windows for the middle cerebral arteries (MCAs) and the orbital window for the internal carotid artery (ICA) on c-TCD. We used c-TCD to detect RLS in patients with suspected ischemic stroke. We enrolled patients who had both sufficient bilateral temporal windows for MCAs and a right orbital window for ICA and performed c-TCD using all three windows simultaneously. We enrolled 106 consecutive patients and identified microembolic signals (MES) in 30 (28%) of them. Among these 30 patients, 15 had MES from all 3 windows. When these 30 patients were defined as being positive for RLS, the rates of detection were 67%, 73%, and 80% from the right temporal, left temporal, and right orbital windows, respectively (P= .795). The right orbital window as well as the temporal window for c-TCD could detect RLS. Insonation from the orbital window should be useful for patients who lack temporal windows. Copyright © 2010 by the American Society of Neuroimaging.

  20. The Medial Temporal Lobe and the Left Inferior Prefrontal Cortex Jointly Support Interference Resolution in Verbal Working Memory

    Science.gov (United States)

    Oztekin, Ilke; Curtis, Clayton E.; McElree, Brian

    2009-01-01

    During working memory retrieval, proactive interference (PI) can be induced by semantic similarity and episodic familiarity. Here, we used fMRI to test hypotheses about the role of the left inferior frontal gyrus (LIFG) and the medial temporal lobe (MTL) regions in successful resolution of PI. Participants studied six-word lists and responded to a…

  1. Treatment for Alexia with Agraphia Following Left Ventral Occipito-Temporal Damage: Strengthening Orthographic Representations Common to Reading and Spelling

    Science.gov (United States)

    Kim, Esther S.; Rising, Kindle; Rapcsak, Steven Z.; Beeson, Pélagie M.

    2015-01-01

    Purpose: Damage to left ventral occipito-temporal cortex can give rise to written language impairment characterized by pure alexia/letter-by-letter (LBL) reading, as well as surface alexia and agraphia. The purpose of this study was to examine the therapeutic effects of a combined treatment approach to address concurrent LBL reading with surface…

  2. The Impact of Sex and Language Dominance on Material-Specific Memory Before and After Left Temporal Lobe Surgery

    Science.gov (United States)

    Helmstaedter, C.; Brosch, T.; Kurthen, M.; Elger, C. E.

    2004-01-01

    Recent findings raised evidence that in early-onset left temporal lobe epilepsy, women show greater functional plasticity for verbal memory than men. In particular, women with lesion- or epilepsy-driven atypical language dominance show an advantage over men. The question asked in this study was whether there is evidence of sex- and language…

  3. Dynamic changes during evacuation of a left temporal abscess in open MRI: technical case report

    Energy Technology Data Exchange (ETDEWEB)

    Bernays, R.L.; Yonekawa, Y. [Department of Neurosurgery, University Hospital, Zurich (Switzerland); Kollias, S.S. [Institute of Neuroradiology, University Hospital of Zurich (Switzerland)

    2002-05-01

    We demonstrate the usefulness of ''near real-time'' neuro-navigation by open MRI systems for guidance of stereotactic evacuation of intracranial abscesses. A 70-year-old patient was referred to our institution with an intracranial left temporal abscess. He presented with headache, senso-motor aphasia and mild right hemiparesis. The abscess (35 x 25 mm) was stereotactically evacuated under MRI guidance, and a recurrence of a daughter abscess was again evacuated on the 9th postoperative day. ''Near real-time'' imaging showed an indentation of the abscess wall of 11 mm along the trajectory. A thermosensitive MRI protocol demonstrated a higher temperature around the abscess capsule than in the brain tissue more distant to the capsule, demonstrating the inflammatory process. The patient had 6 weeks of antibiotic therapy for gram-negative bacteria and was discharged with improved clinical symptoms 5 weeks after admission. Follow-up CT 2 months postoperatively showed a complete resolution of the abscess. Open MRI-guided interventions with ''near real-time'' imaging demonstrate the anatomical changes during an ongoing procedure and can be accommodated for enhancing the overall precision of stereotactic procedures. Thermosensitive MRI protocols are capable of revealing temperature gradients around inflammatory processes. (orig.)

  4. The role of the left anterior temporal lobe in semantic composition vs. semantic memory.

    Science.gov (United States)

    Westerlund, Masha; Pylkkänen, Liina

    2014-05-01

    The left anterior temporal lobe (LATL) is robustly implicated in semantic processing by a growing body of literature. However, these results have emerged from two distinct bodies of work, addressing two different processing levels. On the one hand, the LATL has been characterized as a 'semantic hub׳ that binds features of concepts across a distributed network, based on results from semantic dementia and hemodynamic findings on the categorization of specific compared to basic exemplars. On the other, the LATL has been implicated in combinatorial operations in language, as shown by increased activity in this region associated with the processing of sentences and of basic phrases. The present work aimed to reconcile these two literatures by independently manipulating combination and concept specificity within a minimal MEG paradigm. Participants viewed simple nouns that denoted either low specificity (fish) or high specificity categories (trout) presented in either combinatorial (spotted fish/trout) or non-combinatorial contexts (xhsl fish/trout). By combining these paradigms from the two literatures, we directly compared the engagement of the LATL in semantic memory vs. semantic composition. Our results indicate that although noun specificity subtly modulates the LATL activity elicited by single nouns, it most robustly affects the size of the composition effect when these nouns are adjectivally modified, with low specificity nouns eliciting a much larger effect. We conclude that these findings are compatible with an account in which the specificity and composition effects arise from a shared mechanism of meaning specification. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Quantification of the temporal component of left ventricular asynergy by gated cardiac blood pool scans

    International Nuclear Information System (INIS)

    Solot, G.; Chevigne, M.; Rigo, P.

    1985-01-01

    Fourier analysis (F) has demonstrated that left ventricular (LV) dysfunction can be analyzed in two separate component: an amplitude (AM) and a temporal (T) component. Although the former dominates in hypokinesis and akinesis, and the latter in dyskinesis, they are almost always associated and combine to determine the clinical form of asynergy (AS). The mechanical consequences of the T component cannot be assessed continuously by F which requires setting of a threshold. In this study, the authors have analyzed the potential of a new index; the stroke volume efficiency (SV Eff) to evaluate the importance of T AS in patients (pts) with coronary artery disease studied by gated blood pool scans. The authors have studied 14 controls, 8 pts with coronary artery disease without infarction, 56 pts with myocardial infarction (MI) and 21 pts with LV aneurysm. The SV Eff was calculated as follows after normalization and smoothing of the series: maximum and minimum images were created first and a LV region of interest was traced using the F AM image. The SV Eff ratio was calculated within the LV region of interest as ''diastolic counts - systolic counts/maximum counts - minimum counts''. The SV Eff in controls was 94% +- 2. The authors conclude that SV Eff provides a quantitative measurement of T component of LV dysfunction and an estimate of the dyskinetic component in pts with LV aneurysm. It should prove useful to study these patients serially

  6. Dynamic changes during evacuation of a left temporal abscess in open MRI: technical case report

    International Nuclear Information System (INIS)

    Bernays, R.L.; Yonekawa, Y.; Kollias, S.S.

    2002-01-01

    We demonstrate the usefulness of ''near real-time'' neuro-navigation by open MRI systems for guidance of stereotactic evacuation of intracranial abscesses. A 70-year-old patient was referred to our institution with an intracranial left temporal abscess. He presented with headache, senso-motor aphasia and mild right hemiparesis. The abscess (35 x 25 mm) was stereotactically evacuated under MRI guidance, and a recurrence of a daughter abscess was again evacuated on the 9th postoperative day. ''Near real-time'' imaging showed an indentation of the abscess wall of 11 mm along the trajectory. A thermosensitive MRI protocol demonstrated a higher temperature around the abscess capsule than in the brain tissue more distant to the capsule, demonstrating the inflammatory process. The patient had 6 weeks of antibiotic therapy for gram-negative bacteria and was discharged with improved clinical symptoms 5 weeks after admission. Follow-up CT 2 months postoperatively showed a complete resolution of the abscess. Open MRI-guided interventions with ''near real-time'' imaging demonstrate the anatomical changes during an ongoing procedure and can be accommodated for enhancing the overall precision of stereotactic procedures. Thermosensitive MRI protocols are capable of revealing temperature gradients around inflammatory processes. (orig.)

  7. A comparison of brain activity associated with language production in brain tumor patients with left and right sided language laterality.

    Science.gov (United States)

    Jansma, J M; Ramsey, N; Rutten, G J

    2015-12-01

    Language dominance is an important factor for clinical decision making in brain tumor surgery. Functional MRI can provide detailed information about the organization of language in the brain. One often used measure derived from fMRI data is the laterality index (LI). The LI is typically based on the ratio between left and right brain activity in a specific region associated with language. Nearly all fMRI language studies show language-related activity in both hemispheres, and as a result the LI shows a large range of values. The clinical significance of the variation in language laterality as measured with the LI is still under debate. In this study, we tested two hypotheses in relation to the LI, measured in Broca's region, and it's right hemisphere homologue: 1: the level of activity in Broca's and it's right hemisphere homologue is mirrored for subjects with an equal but opposite LI; 2: the whole brain language activation pattern differs between subjects with an equal but opposite LI. One hundred sixty-three glioma and meningioma patients performed a verb generation task as part of a standard clinical protocol. We calculated the LI in the pars orbitalis, pars triangularis and pars opercularis of the left inferior frontal gyrus, referred to as Broca's region from here on. In our database, 21 patients showed right lateralized activity, with a moderate average level (-0.32). A second group of 21 patients was selected from the remaining group, for equal but opposite LI (0.32). We compared the level and distribution of activity associated with language production in the left and right hemisphere in these two groups. Patients with left sided laterality showed a significantly higher level of activity in Broca's region than the patients with right sided laterality. However, both groups showed no difference in level of activity in Broca's homologue region in the right hemisphere. Also, we did not see any difference in the pattern of activity between patients with left

  8. Correlation of neuropsychological and metabolic changes after epilepsy surgery in patients with left mesial temporal lobe epilepsy with hippocampal sclerosis.

    Science.gov (United States)

    Güvenç, Canan; Dupont, Patrick; Van den Stock, Jan; Seynaeve, Laura; Porke, Kathleen; Dries, Eva; Van Bouwel, Karen; van Loon, Johannes; Theys, Tom; Goffin, Karolien E; Van Paesschen, Wim

    2018-04-12

    Epilepsy surgery often causes changes in cognition and cerebral glucose metabolism. Our aim was to explore relationships between pre- and postoperative cerebral metabolism as measured with 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) and neuropsychological test scores in patients with left mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS), who were rendered seizure-free after epilepsy surgery. Thirteen patients were included. All had neuropsychological testing and an interictal FDG-PET scan of the brain pre- and postoperative. Correlations between changes in neuropsychological test scores and metabolism were examined using statistical parametric mapping (SPM). There were no significant changes in the neuropsychological test scores pre- and postoperatively at the group level. Decreased metabolism was observed in the left mesial temporal regions and occipital lobe. Increased metabolism was observed in the bi-frontal and right parietal lobes, temporal lobes, occipital lobes, thalamus, cerebellum, and vermis. In these regions, we did not find a correlation between changes in metabolism and neuropsychological test scores. A significant negative correlation, however, was found between metabolic changes in the precuneus and Boston Naming Test (BNT) scores. There are significant metabolic decreases in the left mesial temporal regions and increases in the bi-frontal lobes; right parietal, temporal, and occipital lobes; right thalamus; cerebellum; and vermis in patients with left MTLE-HS who were rendered seizure-free after epilepsy surgery. We could not confirm that these changes translate into significant cognitive changes. A significant negative correlation was found between changes in confrontation naming and changes in metabolism in the precuneus. We speculate that the precuneus may play a compensatory role in patients with postoperative naming difficulties after left TLE surgery. Understanding of these neural mechanisms may aid in

  9. Distinctive Structural and Effective Connectivity Changes of Semantic Cognition Network across Left and Right Mesial Temporal Lobe Epilepsy Patients

    Directory of Open Access Journals (Sweden)

    Xiaotong Fan

    2016-01-01

    Full Text Available Occurrence of language impairment in mesial temporal lobe epilepsy (mTLE patients is common and left mTLE patients always exhibit a primary problem with access to names. To explore different neuropsychological profiles between left and right mTLE patients, the study investigated both structural and effective functional connectivity changes within the semantic cognition network between these two groups and those from normal controls. We found that gray matter atrophy of left mTLE patients was more severe than that of right mTLE patients in the whole brain and especially within the semantic cognition network in their contralateral hemisphere. It suggested that seizure attacks were rather targeted than random for patients with hippocampal sclerosis (HS in the dominant hemisphere. Functional connectivity analysis during resting state fMRI revealed that subregions of the anterior temporal lobe (ATL in the left HS patients were no longer effectively connected. Further, we found that, unlike in right HS patients, increased causal linking between ipsilateral regions in the left HS epilepsy patients cannot make up for their decreased contralateral interaction. It suggested that weakened contralateral connection and disrupted effective interaction between subregions of the unitary, transmodal hub of the ATL may be the primary cause of anomia in the left HS patients.

  10. Distinctive Structural and Effective Connectivity Changes of Semantic Cognition Network across Left and Right Mesial Temporal Lobe Epilepsy Patients

    Science.gov (United States)

    Fan, Xiaotong; Shang, Kun; Wang, Xiaocui; Wang, Peipei; Shan, Yongzhi; Lu, Jie

    2016-01-01

    Occurrence of language impairment in mesial temporal lobe epilepsy (mTLE) patients is common and left mTLE patients always exhibit a primary problem with access to names. To explore different neuropsychological profiles between left and right mTLE patients, the study investigated both structural and effective functional connectivity changes within the semantic cognition network between these two groups and those from normal controls. We found that gray matter atrophy of left mTLE patients was more severe than that of right mTLE patients in the whole brain and especially within the semantic cognition network in their contralateral hemisphere. It suggested that seizure attacks were rather targeted than random for patients with hippocampal sclerosis (HS) in the dominant hemisphere. Functional connectivity analysis during resting state fMRI revealed that subregions of the anterior temporal lobe (ATL) in the left HS patients were no longer effectively connected. Further, we found that, unlike in right HS patients, increased causal linking between ipsilateral regions in the left HS epilepsy patients cannot make up for their decreased contralateral interaction. It suggested that weakened contralateral connection and disrupted effective interaction between subregions of the unitary, transmodal hub of the ATL may be the primary cause of anomia in the left HS patients. PMID:28018680

  11. Weighing the value of memory loss in the surgical evaluation of left temporal lobe epilepsy: a decision analysis.

    Science.gov (United States)

    Akama-Garren, Elliot H; Bianchi, Matt T; Leveroni, Catherine; Cole, Andrew J; Cash, Sydney S; Westover, M Brandon

    2014-11-01

    Anterior temporal lobectomy is curative for many patients with disabling medically refractory temporal lobe epilepsy, but carries an inherent risk of disabling verbal memory loss. Although accurate prediction of iatrogenic memory loss is becoming increasingly possible, it remains unclear how much weight such predictions should have in surgical decision making. Here we aim to create a framework that facilitates a systematic and integrated assessment of the relative risks and benefits of surgery versus medical management for patients with left temporal lobe epilepsy. We constructed a Markov decision model to evaluate the probabilistic outcomes and associated health utilities associated with choosing to undergo a left anterior temporal lobectomy versus continuing with medical management for patients with medically refractory left temporal lobe epilepsy. Three base-cases were considered, representing a spectrum of surgical candidates encountered in practice, with varying degrees of epilepsy-related disability and potential for decreased quality of life in response to post-surgical verbal memory deficits. For patients with moderately severe seizures and moderate risk of verbal memory loss, medical management was the preferred decision, with increased quality-adjusted life expectancy. However, the preferred choice was sensitive to clinically meaningful changes in several parameters, including quality of life impact of verbal memory decline, quality of life with seizures, mortality rate with medical management, probability of remission following surgery, and probability of remission with medical management. Our decision model suggests that for patients with left temporal lobe epilepsy, quantitative assessment of risk and benefit should guide recommendation of therapy. In particular, risk for and potential impact of verbal memory decline should be carefully weighed against the degree of disability conferred by continued seizures on a patient-by-patient basis. Wiley

  12. Evaluation of lateral margin of left lobe of the liver on CT scan : focus on perisplenic extension

    International Nuclear Information System (INIS)

    Seo, Chang Hye; Cha, Seong Sook; Lee, Byung Jin; Choi, Jae Young; Choi, Seok Jin; Eun, Choong Ki

    1996-01-01

    The perisplenic extension of the left lobe of the liver can be misinterpreted as a splenic or perisplenic lesion on ultrasonography(US) and computed tomography(CT). The purpose of our study is to classify the lateral margin of the left lobe of the liver into three types and to evaluate the incidence and the relationship between each type and abnormal liver on CT scan. A total of 515 abdominal CT scans from patients over 15 years old were retrospectively evaluated. Liver contours were divided into three types on the basis of degree of the left lateral extension of the left lobe of the liver. Type A was defined as the lateral extension of the left lobe of liver to the medial portion of the stomach, type C as the perisplenic portion, and type B as between the two types. Each type was further divided into normal and abnormal liver groups based on clinical, CT, surgical and patholigic findings and evaluated on its ratio of normal and abnormal liver, intrahepatic diseases associated with an abnormal liver and statistical significance between a normal and abnormal liver. The incidence of the three types of liver among the 515 patients was 360(69.9%), 121(23.5%) and 34(6.6%) patients in type A, B and C, respectively. Type C showed normal liver in six patients, which was 2.7% of all normal livers(221/515) and abnormal liver in 28 patients, which was 9.5% of all abnormal livers(294/515). Type A showed normal liver in 49.7%, abnormal liver in 50.3% and there was not statistically significant difference between normal and abnormal liver(p>0.05). Type B showed normal liver in 29.8% and abnormal liver in 70.2%;type C showed normal liver in 17.6%, abnormal liver in 82.4% and there was a statistically significant difference between normal and abnormal liver(P<0.001). The space occupying lesion(SOL) was most common(52.6%) in all the abnormal livers and hepatoma was the most common disease in the SOL(47.2%). In the abnormal type C liver, SOL(58%) and diffuse hepatopathy(32.8%) were

  13. Lesions to the left lateral prefrontal cortex impair decision threshold adjustment for lexical selection.

    Science.gov (United States)

    Anders, Royce; Riès, Stéphanie; Van Maanen, Leendert; Alario, F-Xavier

    Patients with lesions in the left prefrontal cortex (PFC) have been shown to be impaired in lexical selection, especially when interference between semantically related alternatives is increased. To more deeply investigate which computational mechanisms may be impaired following left PFC damage due to stroke, a psychometric modelling approach is employed in which we assess the cognitive parameters of the patients from an evidence accumulation (sequential information sampling) modelling of their response data. We also compare the results to healthy speakers. Analysis of the cognitive parameters indicates an impairment of the PFC patients to appropriately adjust their decision threshold, in order to handle the increased item difficulty that is introduced by semantic interference. Also, the modelling contributes to other topics in psycholinguistic theory, in which specific effects are observed on the cognitive parameters according to item familiarization, and the opposing effects of priming (lower threshold) and semantic interference (lower drift) which are found to depend on repetition. These results are developed for the blocked-cyclic picture naming paradigm, in which pictures are presented within semantically homogeneous (HOM) or heterogeneous (HET) blocks, and are repeated several times per block. Overall, the results are in agreement with a role of the left PFC in adjusting the decision threshold for lexical selection in language production.

  14. Lateralization in the invertebrate brain: left-right asymmetry of olfaction in bumble bee, Bombus terrestris.

    Directory of Open Access Journals (Sweden)

    Gianfranco Anfora

    Full Text Available Brain and behavioural lateralization at the population level has been recently hypothesized to have evolved under social selective pressures as a strategy to optimize coordination among asymmetrical individuals. Evidence for this hypothesis have been collected in Hymenoptera: eusocial honey bees showed olfactory lateralization at the population level, whereas solitary mason bees only showed individual-level olfactory lateralization. Here we investigated lateralization of odour detection and learning in the bumble bee, Bombus terrestris L., an annual eusocial species of Hymenoptera. By training bumble bees on the proboscis extension reflex paradigm with only one antenna in use, we provided the very first evidence of asymmetrical performance favouring the right antenna in responding to learned odours in this species. Electroantennographic responses did not reveal significant antennal asymmetries in odour detection, whereas morphological counting of olfactory sensilla showed a predominance in the number of olfactory sensilla trichodea type A in the right antenna. The occurrence of a population level asymmetry in olfactory learning of bumble bee provides new information on the relationship between social behaviour and the evolution of population-level asymmetries in animals.

  15. Temporal Changes in Left Ventricular Mechanics: Impact of Bed Rest and Exercise

    Science.gov (United States)

    Scott, Jessica M.; Matz, Timothy; Caine, Timothy; Martin, David S.; Downs, Meghan; Ploutz-Snyder, Lori

    2014-01-01

    BACKGROUND Current techniques used to assess cardiac function following spaceflight or head-down tilt bed rest (HDTBR) involve invasive and time consuming procedures such as Swan-Ganz catheterization or cardiac magnetic resonance imaging. An alternative approach, echocardiography, can monitor cardiac morphology and function via sequential measurements of left ventricular (LV) mass and ejection fraction (EF). However, LV mass and EF are insensitive measures of early (subclinical) cardiac deconditioning, and a decrease in LV mass and EF become evident only once significant deconditioning has already occurred. The use of more sensitive and specific echocardiographic techniques such as speckle tracking imaging may address the current limitations of conventional cardiac imaging techniques to provide insight into the magnitude and time course of cardiac deconditioning. METHODS Speckle tracking assessment of longitudinal, radial, and circumferential strain and twist was used to evaluate the impact of 70 days of HDTBR (n=7) and HDTBR + exercise (n=11) on temporal changes in LV mechanics. Echocardiograms were performed pre (BR-2), during (BR31, 70), and following (BR+4hr) HDTBR. Multi-level modeling was used to evaluate the effect of HDTBR condition (Control, Exercise) on cardiac variables. RESULTS Compared to BR-2, longitudinal (BR-2: - 19.0 +/- 1.8%; BR31: -15.9 +/- 2.4%; BR70: -14.9 +/- 2.4%; BR+4hr: -16.0 +/- 2.1%) and radial (BR-2: 15.0 +/- 1.9%; BR31: 12.3 +/- 2.4%; BR70: 11.3 +/- 2.2%; BR+4hr: 13.5 +/- 2.5% ) strains were significantly impaired during and following bed rest (pmechanics for longitudinal strain (BR-2: -19.1 +/- 1.5%; BR 31: -19.0 +/- 2.4%; BR70: -19.1 +/- 2.7%; BR+4hr: -17.8 +/- 2.1%), radial strain (BR-2: 13.8 +/- 2.4; BR31: 14.7 +/- 2.4; BR70: 14.4 +/- 1.6; BR+4hr: 14.4 +/- 2.4), and twist (BR-2: 17.8 +/- 3.6deg; BR31: 18.0 +/- 3.6deg; BR70: 18.2 +/- 5.9deg; BR+4hr: 18.3 +/- 4.2deg). CONCLUSIONS Speckle-tracking echocardiography provides important

  16. Positive schizotypy scores correlate with left visual field interference for negatively valenced emotional words: A lateralized emotional Stroop study.

    Science.gov (United States)

    Van Strien, Jan W; Van Kampen, Dirk

    2009-10-30

    Fourteen men scoring high and 14 men scoring low on a positive schizotypy scale participated in a lateralized emotional Stroop task. Vocal reaction times for color naming of neutral, positive and negative emotional words were recorded. Across participants, the color naming of neutral and emotional words was slightly faster to right than to left visual field presentations. In men with high scores on positive schizotypy, the presentation of negative words to the left visual field (right hemisphere) resulted in significant affective interference with color naming, which was significantly larger than in men with low scores. Correlational analysis also showed that positive schizotypy was significantly associated with emotional interference in response to LVF negative words. The outcome is discussed in terms of right hemispheric engagement in negative emotions in high positive schizotypic men.

  17. Composition of complex numbers: Delineating the computational role of the left anterior temporal lobe.

    Science.gov (United States)

    Blanco-Elorrieta, Esti; Pylkkänen, Liina

    2016-01-01

    What is the neurobiological basis of our ability to create complex messages with language? Results from multiple methodologies have converged on a set of brain regions as relevant for this general process, but the computational details of these areas remain to be characterized. The left anterior temporal lobe (LATL) has been a consistent node within this network, with results suggesting that although it rather systematically shows increased activation for semantically complex structured stimuli, this effect does not extend to number phrases such as 'three books.' In the present work we used magnetoencephalography to investigate whether numbers in general are an invalid input to the combinatory operations housed in the LATL or whether the lack of LATL engagement for stimuli such as 'three books' is due to the quantificational nature of such phrases. As a relevant test case, we employed complex number terms such as 'twenty-three', where one number term is not a quantifier of the other but rather, the two terms form a type of complex concept. In a number naming paradigm, participants viewed rows of numbers and depending on task instruction, named them as complex number terms ('twenty-three'), numerical quantifications ('two threes'), adjectival modifications ('blue threes') or non-combinatory lists (e.g., 'two, three'). While quantificational phrases failed to engage the LATL as compared to non-combinatory controls, both complex number terms and adjectival modifications elicited a reliable activity increase in the LATL. Our results show that while the LATL does not participate in the enumeration of tokens within a set, exemplified by the quantificational phrases, it does support conceptual combination, including the composition of complex number concepts. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  18. Case report 400: Unilateral fusion of odontoid to lateral mass of C1 with pseudoarthrosis on left

    Energy Technology Data Exchange (ETDEWEB)

    Nyska, M; Margulies, J Y; Gomori, J M; Beauvoir, G

    1986-11-01

    A case is described of a 19-year-old woman who presented with pain in the neck of several months duration. Torticolis and limitation of rotation of the head and neck to the right were observed. Plain films of the cervical spine were interpreted as normal, but plain film tomography and CT studies demonstrated an unusual anomaly, consisting of fusion of the odontoid process to the right lateral mass of C1 and a pseudoarthrosis in the anterior mass on the left side. (orig./SHA).

  19. Strong rightward lateralization of the dorsal attentional network in left-handers with right sighting-eye: an evolutionary advantage.

    Science.gov (United States)

    Petit, Laurent; Zago, Laure; Mellet, Emmanuel; Jobard, Gaël; Crivello, Fabrice; Joliot, Marc; Mazoyer, Bernard; Tzourio-Mazoyer, Nathalie

    2015-03-01

    Hemispheric lateralization for spatial attention and its relationships with manual preference strength and eye preference were studied in a sample of 293 healthy individuals balanced for manual preference. Functional magnetic resonance imaging was used to map this large sample while performing visually guided saccadic eye movements. This activated a bilateral distributed cortico-subcortical network in which dorsal and ventral attentional/saccadic pathways elicited rightward asymmetrical activation depending on manual preference strength and sighting eye. While the ventral pathway showed a strong rightward asymmetry irrespective of both manual preference strength and eye preference, the dorsal frontoparietal network showed a robust rightward asymmetry in strongly left-handers, even more pronounced in left-handed subjects with a right sighting-eye. Our findings brings support to the hypothesis that the origin of the rightward hemispheric dominance for spatial attention may have a manipulo-spatial origin neither perceptual nor motor per se but rather reflecting a mechanism by which a spatial context is mapped onto the perceptual and motor activities, including the exploration of the spatial environment with eyes and hands. Within this context, strongly left-handers with a right sighting-eye may benefit from the advantage of having the same right hemispheric control of their dominant hand and visuospatial attention processing. We suggest that this phenomenon explains why left-handed right sighting-eye athletes can outperform their competitors in sporting duels and that the prehistoric and historical constancy of the left-handers ratio over the general population may relate in part on the hemispheric specialization of spatial attention. © 2014 Wiley Periodicals, Inc.

  20. Differentiation of medial or lateral temporal lobe epilepsy by F-18-fluorodeoxyglucose positron emission tomography: comparative study with magnetic resonance imaging in 113 surgically and pathologically proven patients

    International Nuclear Information System (INIS)

    Lee, Dong Soo; Lee, Sang Kun; Chang, Ki Hyun; Chung, Chun Kee; Choi, Ki Young; Chung, June Key; Lee, Myung Chul

    1999-01-01

    As mesial temporal lobe epilepsy (TLE) shows hypometabolism of medial and lateral temporal lobe, we investigated whether symmetric uptake of F-18-FDG in medial temporal lobes can differentiate mesial from lateral TLE. In 113 patients (83 mesial TLE, 30 lateral TLE) who underwent anterior temporal lobectomy and/or corticectomy with good surgical outcome, we performed F-18-FDG PET and compared F-18-FDG uptake of medial and lateral temporal lobes. All the patients with mesial TLE had hippocampal sclerosis except one congenital abnormal hippocampus. Patients with lateral TLE revealed cerebromalacia, microdysgenesis, arteriovenous malformation, old contusion, and cortical dysplasia. Sensitivity of F-18-FDG PET and MR for mesial TLE was 84% (70/83) and 73% (62/83), respectively. Sensitivity of F-18-FDG PET and MR for lateral TLE was 90% (27/30) and 66% (20/30), respectively. Twelve patients were normal on F-18-FDG PET. 101 patients had hypometabolism of lateral temporal lobe. Among 88 patients who showed hypometabolism of medial temporal lobe as well as lateral temporal lobe, 70 were mesial TLE patients and 18 were lateral TLE on pathologic examination. Positive predictive value of medial temporal hypometabolism for mesial TLE was 80%. Among 13 patients who showed hypometabolism of only lateral temporal lobe, 4 were mesial TLE and 9 were lateral TLE. Positive predictive value of hypometabolism of lateral temporal lobe for the diagnosis of lateral TLE was 69% (9/ 13). Normal MR findings stood against medial TLE, whose negative predictive value was 66%. Lateral temporal lobe epilepsy should be suspected when there is decreased F-18-FDG uptake in lateral temporal lobe with normal uptake in medial temporal lobe

  1. Exposure to lateral collision in signalized intersections with protected left turn under different traffic control strategies.

    Science.gov (United States)

    Midenet, Sophie; Saunier, Nicolas; Boillot, Florence

    2011-11-01

    This paper proposes an original definition of the exposure to lateral collision in signalized intersections and discusses the results of a real world experiment. This exposure is defined as the duration of situations where the stream that is given the right-of-way goes through the conflict zone while road users are waiting in the cross-traffic approach. This measure, obtained from video sensors, makes it possible to compare different operating conditions such as different traffic signal strategies. The data from a real world experiment is used, where the adaptive real-time strategy CRONOS (ContRol Of Networks by Optimization of Switchovers) and a time-plan strategy with vehicle-actuated ranges alternately controlled an isolated intersection near Paris. Hourly samples with similar traffic volumes are compared and the exposure to lateral collision is different in various areas of the intersection and various traffic conditions for the two strategies. The total exposure under peak hour traffic conditions drops by roughly 5 min/h with the CRONOS strategy compared to the time-plan strategy, which occurs mostly on entry streams. The results are analyzed through the decomposition of cycles in phase sequences and recommendations are made for traffic control strategies. Copyright © 2011 Elsevier Ltd. All rights reserved.

  2. Pulmonary Hypertension with Left Heart Disease: Prevalence, Temporal Shifts in Etiologies and Outcome.

    Science.gov (United States)

    Weitsman, Tatyana; Weisz, Giora; Farkash, Rivka; Klutstein, Marc; Butnaru, Adi; Rosenmann, David; Hasin, Tal

    2017-11-01

    Pulmonary hypertension has many causes. While it is conventionally thought that the most prevalent is left heart disease, little information about its proportion, causes, and implications on outcome is available. Between 1993 and 2015, 12,115 of 66,949 (18%) first adult transthoracic echocardiograms were found to have tricuspid incompetence gradient ≥40 mm Hg, a pulmonary hypertension surrogate. Left heart disease was identified in 8306 (69%) and included valve malfunction in 4115 (49%), left ventricular systolic dysfunction in 2557 (31%), and diastolic dysfunction in 1776 (21%). Patients with left heart disease, as compared with those without left heart disease, were of similar age, fewer were females (50% vs 63% P pulmonary hypertension with left heart disease. Independent predictors of mortality were age (hazard ratio [HR] 1.05; 95% CI, 1.04-1.05; P pulmonary hypertension but without left heart disease (HR 1.30; 95% CI, 1.20-1.42 and HR 1.44; 95% CI, 1.33-1.55, respectively; P Pulmonary hypertension was found to be associated with left heart disease in 69% of patients. Among these patients, valve malfunction and diastolic dysfunction emerged as prominent causes. Left ventricular dysfunction carries additional risk to patients with pulmonary hypertension. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Atypical temporal activation pattern and central-right brain compensation during semantic judgment task in children with early left brain damage.

    Science.gov (United States)

    Chang, Yi-Tzu; Lin, Shih-Che; Meng, Ling-Fu; Fan, Yang-Teng

    In this study we investigated the event-related potentials (ERPs) during the semantic judgment task (deciding if the two Chinese characters were semantically related or unrelated) to identify the timing of neural activation in children with early left brain damage (ELBD). The results demonstrated that compared with the controls, children with ELBD had (1) competitive accuracy and reaction time in the semantic judgment task, (2) weak operation of the N400, (3) stronger, earlier and later compensational positivities (referred to the enhanced P200, P250, and P600 amplitudes) in the central and right region of the brain to successfully engage in semantic judgment. Our preliminary findings indicate that temporally postlesional reorganization is in accordance with the proposed right-hemispheric organization of speech after early left-sided brain lesion. During semantic processing, the orthography has a greater effect on the children with ELBD, and a later semantic reanalysis (P600) is required due to the less efficient N400 at the former stage for semantic integration. Copyright © 2018 Elsevier Inc. All rights reserved.

  4. Left temporal and temporoparietal brain activity depends on depth of word encoding: a magnetoencephalographic study in healthy young subjects.

    Science.gov (United States)

    Walla, P; Hufnagl, B; Lindinger, G; Imhof, H; Deecke, L; Lang, W

    2001-03-01

    Using a 143-channel whole-head magnetoencephalograph (MEG) we recorded the temporal changes of brain activity from 26 healthy young subjects (14 females) related to shallow perceptual and deep semantic word encoding. During subsequent recognition tests, the subjects had to recognize the previously encoded words which were interspersed with new words. The resulting mean memory performances across all subjects clearly mirrored the different levels of encoding. The grand averaged event-related fields (ERFs) associated with perceptual and semantic word encoding differed significantly between 200 and 550 ms after stimulus onset mainly over left superior temporal and left superior parietal sensors. Semantic encoding elicited higher brain activity than perceptual encoding. Source localization procedures revealed that neural populations of the left temporal and temporoparietal brain areas showed different activity strengths across the whole group of subjects depending on depth of word encoding. We suggest that the higher brain activity associated with deep encoding as compared to shallow encoding was due to the involvement of more neural systems during the processing of visually presented words. Deep encoding required more energy than shallow encoding but for all that led to a better memory performance. Copyright 2001 Academic Press.

  5. Language localization in cases of left temporal lobe arachnoid cyst : Evidence against interhemispheric reorganization

    NARCIS (Netherlands)

    Stowe, LA; Go, KG; Pruim, J; den Dunnen, W; Meiners, LC; Paans, AMJ

    2000-01-01

    We investigated whether left-hemisphere arachnoid cysts lead to reorganization of the language function using PET. A group analysis demonstrated that patients showed no more right-hemisphere activation than a matched control group. Several patients had clear language localizations in the left

  6. The regional neuronal activity in left posterior middle temporal gyrus is correlated with the severity of chronic aphasia.

    Science.gov (United States)

    Li, Jianlin; Du, Dunren; Gao, Wei; Sun, Xichun; Xie, Haizhu; Zhang, Gang; Li, Jian; Li, Honglun; Li, Kefeng

    2017-01-01

    Aphasia is one of the most disabling cognitive deficits affecting >2 million people in the USA. The neuroimaging characteristics of chronic aphasic patients (>6 months post onset) remain largely unknown. The objective of this study was to investigate the regional signal changes of spontaneous neuronal activity of brain and the inter-regional connectivity in chronic aphasia. Resting-state blood oxygenation level-dependent functional magnetic resonance imaging (fMRI) was used to obtain fMRI data from 17 chronic aphasic patients and 20 healthy control subjects in a Siemens Verio 3.0T MR Scanner. The amplitude of low-frequency fluctuation (ALFF) was determined, which directly reflects the regional neuronal activity. The functional connectivity (FC) of fMRI was assessed using a seed voxel linear correlation approach. The severity of aphasia was evaluated by aphasia quotient (AQ) scores obtained from Western Aphasia Battery test. Compared with normal subjects, aphasic patients showed decreased ALFF values in the regions of left posterior middle temporal gyrus (PMTG), left medial prefrontal gyrus, and right cerebellum. The ALFF values in left PMTG showed strong positive correlation with the AQ score (coefficient r =0.79, P temporal gyrus (BA20), fusiform gyrus (BA37), and inferior frontal gyrus (BA47\\45\\44). Left PMTG might play an important role in language dysfunction of chronic aphasia, and ALFF value might be a promising indicator to evaluate the severity of aphasia.

  7. Functional substrate for memory function differences between patients with left and right mesial temporal lobe epilepsy associated with hippocampal sclerosis.

    Science.gov (United States)

    Jin, Seung-Hyun; Chung, Chun Kee

    2015-10-01

    Little is known about the functional substrate for memory function differences in patients with left or right mesial temporal lobe epilepsy (mTLE) associated with hippocampal sclerosis (HS) from an electrophysiological perspective. To characterize these differences, we hypothesized that hippocampal theta connectivity in the resting-state might be different between patients with left and right mTLE with HS and be correlated with memory performance. Resting-state hippocampal theta connectivity, identified via whole-brain magnetoencephalography, was evaluated. Connectivity and memory function in 41 patients with mTLE with HS (left mTLE=22; right mTLE=19) were compared with those in 46 age-matched healthy controls and 28 patients with focal cortical dysplasia (FCD) but without HS. Connectivity between the right hippocampus and the left middle frontal gyrus was significantly stronger in patients with right mTLE than in patients with left mTLE. Moreover, this connectivity was positively correlated with delayed verbal recall and recognition scores in patients with mTLE. Patients with left mTLE had greater delayed recall impairment than patients with right mTLE and FCD. Similarly, delayed recognition performance was worse in patients with left mTLE than in patients with right mTLE and FCD. No significant differences in memory function between patients with right mTLE and FCD were detected. Patients with right mTLE showed significantly stronger hippocampal theta connectivity between the right hippocampus and left middle frontal gyrus than patients with FCD and left mTLE. Our results suggest that right hippocampal-left middle frontal theta connectivity could be a functional substrate that can account for differences in memory function between patients with left and right mTLE. This functional substrate might be related to different compensatory mechanisms against the structural hippocampal lesions in left and right mTLE groups. Given the positive correlation between

  8. Decreased left middle temporal gyrus volume in antipsychotic drug-naive, first-episode schizophrenia patients and their healthy unaffected siblings.

    Science.gov (United States)

    Hu, Maorong; Li, Jun; Eyler, Lisa; Guo, Xiaofeng; Wei, Qingling; Tang, Jingsong; Liu, Feng; He, Zhong; Li, Lihua; Jin, Hua; Liu, Zhening; Wang, Juan; Liu, Fang; Chen, Huafu; Zhao, Jingping

    2013-03-01

    The shared neuropathological characteristics of patients with schizophrenia and their siblings might represent intermediate phenotypes that could be used to investigate genetic susceptibility to the illness. We sought to discover gray matter volume differences in patients with schizophrenia and their unaffected siblings with voxel-based morphometry (VBM). We recruited antipsychotic drug-naive, first-episode schizophrenia (FES) patients, their unaffected siblings and age-, sex- and handedness-matched healthy controls. We used VBM to investigate differences in gray matter volume among the 3 groups. There were significant gray matter volumetric differences among the 3 groups in bilateral hippocampal and parahippocampal gyri, bilateral middle temporal gyri, and superior temporal gyri (FDR ptemporal gyrus, and volume of this region was not different between siblings and patients. Our findings confirm and extend previous VBM analyses in schizophrenia and it indicate that schizophrenia may be characterized by an abnormal development of cerebral lateralization. Furthermore, these data argue that patients and their unaffected siblings might share decreases in the gray matter volume of the left middle temporal gyrus, and this regional reduction might be a potential endophenotype for schizophrenia. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Spontaneous neural activity in the right superior temporal gyrus and left middle temporal gyrus is associated with insight level in obsessive-compulsive disorder.

    Science.gov (United States)

    Fan, Jie; Zhong, Mingtian; Gan, Jun; Liu, Wanting; Niu, Chaoyang; Liao, Haiyan; Zhang, Hongchun; Tan, Changlian; Yi, Jinyao; Zhu, Xiongzhao

    2017-01-01

    Insight into illness is an important issue for psychiatry disorder. Although the existence of a poor insight subtype of obsessive-compulsive disorder (OCD) was recognized in the DSM-IV, and the insight level in OCD was specified further in DSM-V, the neural underpinnings of insight in OCD have been rarely explored. The present study was designed to bridge this research gap by using resting-state functional magnetic resonance imaging (fMRI). Spontaneous neural activity were examined in 19 OCD patients with good insight (OCD-GI), 18 OCD patients with poor insight (OCD-PI), and 25 healthy controls (HC) by analyzing the amplitude of low-frequency fluctuation (ALFF) in the resting state. Pearson correlation analysis was performed between regional ALFFs and insight levels among OCD patients. OCD-GI and OCD-PI demonstrated overlapping and distinct brain alterations. Notably, compared with OCD-GI, tOCD-PI had reduced ALFF in left middle temporal gyrus (MTG) and right superior temporal gyrus (STG), as well as increased ALFF in right middle occipital gyrus. Further analysis revealed that ALFF values for the left MTG and right STG were correlated negatively with insight level in patients with OCD. Relatively small sample size and not all patients were un-medicated are our major limitations. Spontaneous brain activity in left MTG and right STG may be neural underpinnings of insight in OCD. Our results suggest the great role of human temporal brain regions in understanding insight, and further underscore the importance of considering insight presentation in understanding the clinical heterogeneity of OCD. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Hyperfamiliarity for unknown faces after left lateral temporo-occipital venous infarction: a double dissociation with prosopagnosia.

    Science.gov (United States)

    Vuilleumier, Patrik; Mohr, Christine; Valenza, Nathalie; Wetzel, Corinne; Landis, Theodor

    2003-04-01

    Right hemisphere dominance in face processing is well established and unilateral right inferior temporo-occipital damage can result in prosopagnosia. Here, we describe a 21-year-old right-handed woman with acute impairment in face recognition that selectively concerned unfamiliar faces, following a focal left lateral temporo-occipital venous infarct. She was severely impaired in discerning that unknown people seen in everyday life were unfamiliar, although she had no difficulty recognizing familiar people. Thus, she had no prosopagnosia, but abnormal 'hyperfamiliarity' for unknown faces. Her difficulty was not accompanied by delusions or deficits in discrimination, identification or memory for faces. Standard neuropsychological testing showed that her recognition of familiar faces was entirely normal. By contrast, her sense of personally knowing faces was severely impaired when unknown faces evoked weak signals of familiarity based on spurious cues, to the extent that she would misattribute fame to faces that were unknown but to which she had been incidentally exposed on a prior occasion. Priming experiments also revealed that, unlike normal subjects, she made familiarity judgements without accessing semantic identity representations. Moreover, in face recognition tests, she generally showed bias in that she relied more on right-hemisphere strategies to identify global traits and less on left-hemisphere processes compared with healthy subjects. This case provides novel evidence for a differential contribution of the two hemispheres to face recognition. Hyperfamiliarity for unknown faces might arise from an imbalance between reciprocal hemispheric functions in face recognition, with relative hypoactivation of left hemisphere processes but hyperactivation of right-hemisphere processes for retrieving stored associations about people, linking seen faces to representations of affective and personal relevance. Hence, abnormal bias in attributing some personal meaning to

  11. Examining Brain-Cognition Effects of Ginkgo Biloba Extract: Brain Activation in the Left Temporal and Left Prefrontal Cortex in an Object Working Memory Task

    Directory of Open Access Journals (Sweden)

    R. B. Silberstein

    2011-01-01

    Full Text Available Ginkgo Biloba extract (GBE is increasingly used to alleviate symptoms of age related cognitive impairment, with preclinical evidence pointing to a pro-cholinergic effect. While a number of behavioral studies have reported improvements to working memory (WM associated with GBE, electrophysiological studies of GBE have typically been limited to recordings during a resting state. The current study investigated the chronic effects of GBE on steady state visually evoked potential (SSVEP topography in nineteen healthy middle-aged (50-61 year old male participants whilst completing an object WM task. A randomized double-blind crossover design was employed in which participants were allocated to receive 14 days GBE and 14 days placebo in random order. For both groups, SSVEP was recorded from 64 scalp electrode sites during the completion of an object WM task both pre- and 14 days post-treatment. GBE was found to improve behavioural performance on the WM task. GBE was also found to increase the SSVEP amplitude at occipital and frontal sites and increase SSVEP latency at left temporal and left frontal sites during the hold component of the WM task. These SSVEP changes associated with GBE may represent more efficient processing during WM task completion.

  12. Automated volumetry of temporal horn of lateral ventricle for detection of Alzheimer's disease in CT scan

    Science.gov (United States)

    Takahashi, Noriyuki; Kinoshita, Toshibumi; Ohmura, Tomomi; Matsuyama, Eri; Toyoshima, Hideto

    2018-02-01

    The rapid increase in the incidence of Alzheimer's disease (AD) has become a critical issue in low and middle income countries. In general, MR imaging has become sufficiently suitable in clinical situations, while CT scan might be uncommonly used in the diagnosis of AD due to its low contrast between brain tissues. However, in those countries, CT scan, which is less costly and readily available, will be desired to become useful for the diagnosis of AD. For CT scan, the enlargement of the temporal horn of the lateral ventricle (THLV) is one of few findings for the diagnosis of AD. In this paper, we present an automated volumetry of THLV with segmentation based on Bayes' rule on CT images. In our method, first, all CT data sets are normalized into an atlas by using linear affine transformation and non-linear wrapping techniques. Next, a probability map of THLV is constructed in the normalized data. Then, THLV regions are extracted based on Bayes' rule. Finally, the volume of the THLV is evaluated. This scheme was applied to CT scans from 20 AD patients and 20 controls to evaluate the performance of the method for detecting AD. The estimated THLV volume was markedly increased in the AD group compared with the controls (P < .0001), and the area under the receiver operating characteristic curve (AUC) was 0.921. Therefore, this computerized method may have the potential to accurately detect AD on CT images.

  13. Differential contribution of right and left temporo-occipital and anterior temporal lesions to face recognition disorders

    Directory of Open Access Journals (Sweden)

    Guido eGainotti

    2011-06-01

    Full Text Available In the study of prosopagnosia, several issues (such as the specific or non-specific manifestations of prosopagnosia, the unitary or non-unitary nature of this syndrome and the mechanisms underlying face recognition disorders are still controversial. Two main sources of variance partially accounting for these controversies could be the qualitative differences between the face recognition disorders observed in patients with prevalent lesions of the right or left hemisphere and in those with lesions encroaching upon the temporo-occipital or the (right anterior temporal cortex.Results of our review seem to confirm these suggestions. Indeed, they show that (a the most specific forms of prosopagnosia are due to lesions of a right posterior network including the OFA and the FFA, whereas (b the face identification defects observed in patients with left temporo-occipital lesions seem due to a semantic defect impeding access to person-specific semantic information from the visual modality. Furthermore, face recognition defects resulting from right anterior temporal lesions can usually be considered as part of a multimodal people recognition disorder.The implications of our review are, therefore, the following: (1 to consider the components of visual agnosia often observed in prosopagnosic patients with bilateral temporo-occipital lesions as part of a semantic defect, resulting from left-sided lesions (and not from prosopagnosia proper; (2 to systematically investigate voice recognition disorders in patients with right anterior temporal lesions to determine whether the face recognition defect should be considered a form of ‘associative prosopagnosia’ or a form of the ‘multimodal people recognition disorder’.

  14. Disrupted topological properties of brain white matter networks in left temporal lobe epilepsy: a diffusion tensor imaging study.

    Science.gov (United States)

    Xu, Y; Qiu, S; Wang, J; Liu, Z; Zhang, R; Li, S; Cheng, L; Liu, Z; Wang, W; Huang, R

    2014-10-24

    Mesial temporal lobe epilepsy (mTLE) is the most common drug-refractory focal epilepsy in adults. Although previous functional and morphological studies have revealed abnormalities in the brain networks of mTLE, the topological organization of the brain white matter (WM) networks in mTLE patients is still ambiguous. In this study, we constructed brain WM networks for 14 left mTLE patients and 22 age- and gender-matched normal controls using diffusion tensor tractography and estimated the alterations of network properties in the mTLE brain networks using graph theoretical analysis. We found that networks for both the mTLE patients and the controls exhibited prominent small-world properties, suggesting a balanced topology of integration and segregation. However, the brain WM networks of mTLE patients showed a significant increased characteristic path length but significant decreased global efficiency, which indicate a disruption in the organization of the brain WM networks in mTLE patients. Moreover, we found significant between-group differences in the nodal properties in several brain regions, such as the left superior temporal gyrus, left hippocampus, the right occipital and right temporal cortices. The robustness analysis showed that the results were likely to be consistent for the networks constructed with different definitions of node and edge weight. Taken together, our findings may suggest an adverse effect of epileptic seizures on the organization of large-scale brain WM networks in mTLE patients. Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.

  15. Auditory verbal hallucinations are related to cortical thinning in the left middle temporal gyrus of patients with schizophrenia.

    Science.gov (United States)

    Cui, Y; Liu, B; Song, M; Lipnicki, D M; Li, J; Xie, S; Chen, Y; Li, P; Lu, L; Lv, L; Wang, H; Yan, H; Yan, J; Zhang, H; Zhang, D; Jiang, T

    2018-01-01

    Auditory verbal hallucinations (AVHs) are one of the most common and severe symptoms of schizophrenia, but the neuroanatomical abnormalities underlying AVHs are not well understood. The present study aims to investigate whether AVHs are associated with cortical thinning. Participants were schizophrenia patients from four centers across China, 115 with AVHs and 93 without AVHs, as well as 261 healthy controls. All received 3 T T1-weighted brain scans, and whole brain vertex-wise cortical thickness was compared across groups. Correlations between AVH severity and cortical thickness were also determined. The left middle part of the middle temporal gyrus (MTG) was significantly thinner in schizophrenia patients with AVHs than in patients without AVHs and healthy controls. Inferences were made using a false discovery rate approach with a threshold at p < 0.05. Left MTG thickness did not differ between patients without AVHs and controls. These results were replicated by a meta-analysis showing them to be consistent across the four centers. Cortical thickness of the left MTG was also found to be inversely correlated with hallucination severity across all schizophrenia patients. The results of this multi-center study suggest that an abnormally thin left MTG could be involved in the pathogenesis of AVHs in schizophrenia.

  16. Selective activation around the left occipito-temporal sulcus for words relative to pictures: individual variability or false positives?

    Science.gov (United States)

    Wright, Nicholas D; Mechelli, Andrea; Noppeney, Uta; Veltman, Dick J; Rombouts, Serge A R B; Glensman, Janice; Haynes, John-Dylan; Price, Cathy J

    2008-08-01

    We used high-resolution fMRI to investigate claims that learning to read results in greater left occipito-temporal (OT) activation for written words relative to pictures of objects. In the first experiment, 9/16 subjects performing a one-back task showed activation in > or =1 left OT voxel for words relative to pictures (P or =1 left OT voxel for words relative to pictures. However, at this low statistical threshold false positives need to be excluded. The semantic decision paradigm was therefore repeated, within subject, in two different scanners (1.5 and 3 T). Both scanners consistently localised left OT activation for words relative to fixation and pictures relative to words, but there were no consistent effects for words relative to pictures. Finally, in a third experiment, we minimised the voxel size (1.5 x 1.5 x 1.5 mm(3)) and demonstrated a striking concordance between the voxels activated for words and pictures, irrespective of task (naming vs. one-back) or script (English vs. Hebrew). In summary, although we detected differential activation for words relative to pictures, these effects: (i) do not withstand statistical rigour; (ii) do not replicate within or between subjects; and (iii) are observed in voxels that also respond to pictures of objects. Our findings have implications for the role of left OT activation during reading. More generally, they show that studies using low statistical thresholds in single subject analyses should correct the statistical threshold for the number of comparisons made or replicate effects within subject. (c) 2007 Wiley-Liss, Inc.

  17. Computer-assisted lateralization of unilateral temporal lobe epilepsy using Z-score parametric F-18 FDG PET images

    International Nuclear Information System (INIS)

    Wong, Ching-yee Oliver; Gannon, James; Bong, Jeffrey; Wong, Christiana O; Saha, Gopal B

    2007-01-01

    To evaluate the use of unbiased computer-assisted lateralization of temporal lobe epilepsy (TLE) by z-score parametric PET imaging (ZPET). 38 patients with histologically proven unilateral TLE due to pure hippocampal sclerosis, referred for pre-surgical PET evaluation of intractable seizure over a 5-year period, were included. The F-18 FDG images were oriented along temporal long axis and then transformed into ZPET images on a voxel by voxel basis. Multiple regions of interests (21 in total) were placed on cortical, subcortical and cerebellar structures on twenty-eight out of 38 patients with totally seizure-free (class I) outcome. Paired t-tests with Bonferroni correction were used to determine the location of the most asymmetric regions as variables for subsequent discriminant analysis of the entire group of the patients. The computer program identified the anterior half of the temporal lobe (p < 0.0005) and thalami (p = 0.021) as the most asymmetric regions in TLE patients with Class I outcome. Discriminant analysis using z-scores from a total of 8 ROIs (in 4 pairs) on these structures correctly lateralized thirty-seven out of 38 (97%) patients (sensitivity = 94%; specificity = 100%). The only false localization came from a patient with equivocal z-scores on the temporal lobes and this patient turned out to have poor outcome. The computer-assisted lateralization of TLE using ZPET provides an accurate, fast and objective way of seizure evaluation

  18. The left middle temporal gyrus in the middle of an impaired social-affective communication network in social anxiety disorder.

    Science.gov (United States)

    Yun, Je-Yeon; Kim, Jae-Chang; Ku, Jeonghun; Shin, Jung-Eun; Kim, Jae-Jin; Choi, Soo-Hee

    2017-05-01

    Previous studies on patients diagnosed with social anxiety disorder (SAD) reported changed patterns of the resting-state functional connectivity network (rs-FCN) between the prefrontal cortices and other prefrontal, amygdalar or striatal regions. Using a graph theory approach, this study explored the modularity-based community profile and patterns of inter-/intra-modular communication for the rs-FCN in SAD. In total, for 28 SAD patients and 27 healthy controls (HC), functional magnetic resonance imaging (fMRI) data were acquired in resting-state and subjected to a graph theory analysis. The within-module degree z-score for a hub region [out of a total of 10 hub regions ranked using the participation coefficient] named left middle temporal gyrus was impaired in SAD compared to HC, proportional to the severity of clinician-scored and patient-reported functional impairment in SAD. Most of participants included in this study were undergraduate students in their early-to-mid 20's. This study showed the importance of functional communication from the left middle temporal gyrus with other opercular-insular-subcortical regions for better objective functioning and lesser subjective disability in SAD. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  19. Effect of the left lateral recumbent position compared with the supine and upright positions on placental blood flow in normal late pregnancy.

    Science.gov (United States)

    Suonio, S; Simpanen, A L; Olkkonen, H; Haring, P

    1976-02-01

    The placental blood flow was assessed by the 99mTc accumulation method in 10 normal pregnancies in the left lateral recumbent position accomplished by a 15 degree wedge and in the supine position. The postural change caused a 17% decrease in the mean placental accumulation rate, which was not statistically significant. Ten patients were moved from the left lateral recumbent position to the upright position, which caused a statistically significant 23% decrease in the mean accumulation rate. Other haemodynamic variables studied were the maternal heart rate and the systolic and diastolic blood pressures. The clinical significance of the haemodynamic changes produced by alterations in posture are briefly discussed.

  20. Abnormal left superior temporal gyrus volumes in children and adolescents with bipolar disorder: a magnetic resonance imaging study.

    Science.gov (United States)

    Chen, Hua Hsua; Nicoletti, Mark A; Hatch, John P; Sassi, Roberto B; Axelson, David; Brambilla, Paolo; Monkul, E Serap; Keshavan, Matcheri S; Ryan, Neal D; Birmaher, Boris; Soares, Jair C

    2004-06-03

    Abnormalities in left superior temporal gyrus (STG) have been reported in adult bipolar patients. However, it is not known whether such abnormalities are already present early in the course of this illness. Magnetic resonance imaging (MRI) morphometric analysis of STG was performed in 16 DSM-IV children and adolescents with bipolar disorder (mean age+/-SD 15.5+/-3.4 years) and 21 healthy controls (mean age+/-SD 16.9+/-3.8 years). Subjects underwent a 3D spoiled gradient recalled acquisition MRI examination. Using analysis of covariance with age, gender and intra-cranial brain volume as covariates, we found significantly smaller left total STG volumes in bipolar patients (12.5+/-1.5 cm(3)) compared with healthy controls (13.6+/-2.5 cm(3)) (F=4.45, d.f.=1, 32, P=0.04). This difference was accounted for by significantly smaller left and right STG white matter volumes in bipolar patients. Decreased white matter connections may be the core of abnormalities in STG, which is an important region for speech, language and communication, and could possibly underlie neurocognitive deficits present in bipolar patients.

  1. Effects of Time-Compressed Speech Training on Multiple Functional and Structural Neural Mechanisms Involving the Left Superior Temporal Gyrus.

    Science.gov (United States)

    Maruyama, Tsukasa; Takeuchi, Hikaru; Taki, Yasuyuki; Motoki, Kosuke; Jeong, Hyeonjeong; Kotozaki, Yuka; Nakagawa, Seishu; Nouchi, Rui; Iizuka, Kunio; Yokoyama, Ryoichi; Yamamoto, Yuki; Hanawa, Sugiko; Araki, Tsuyoshi; Sakaki, Kohei; Sasaki, Yukako; Magistro, Daniele; Kawashima, Ryuta

    2018-01-01

    Time-compressed speech is an artificial form of rapidly presented speech. Training with time-compressed speech (TCSSL) in a second language leads to adaptation toward TCSSL. Here, we newly investigated the effects of 4 weeks of training with TCSSL on diverse cognitive functions and neural systems using the fractional amplitude of spontaneous low-frequency fluctuations (fALFF), resting-state functional connectivity (RSFC) with the left superior temporal gyrus (STG), fractional anisotropy (FA), and regional gray matter volume (rGMV) of young adults by magnetic resonance imaging. There were no significant differences in change of performance of measures of cognitive functions or second language skills after training with TCSSL compared with that of the active control group. However, compared with the active control group, training with TCSSL was associated with increased fALFF, RSFC, and FA and decreased rGMV involving areas in the left STG. These results lacked evidence of a far transfer effect of time-compressed speech training on a wide range of cognitive functions and second language skills in young adults. However, these results demonstrated effects of time-compressed speech training on gray and white matter structures as well as on resting-state intrinsic activity and connectivity involving the left STG, which plays a key role in listening comprehension.

  2. Clinical and eeg analysis of mesial and lateral temporal lobe seizures Análise clínica e eletrencefalográfica de crises epilépticas temporais de origem mesial e lateral

    Directory of Open Access Journals (Sweden)

    FÁBIO GALVÃO DANTAS

    1998-09-01

    Full Text Available The analysis of the temporal lobe seizures through video-EEG systems shows that they often consist of a sequence of clinical and EEG features which may suggest the localization and the lateralization of the epileptogenic lobe. We analyzed clinical and EEG features of 50 temporal lobe seizures which were separated in group 1 with 25 patients (related to mesial temporal sclerosis and group 2 with 25 patients (other neocortical temporal lesions. Among the auras, the epigastric type was the most frequent and predominated in group 1. There were differences between the two groups, considering dystonic and tonic posturing and versive head and eye movements. Dystonic posturing was always contralateral to the ictal onset and was considered the most useful lateralizing clinical feature. Ictal speech, spitting and blinking automatisms, prolonged disorientation for place and a greatest percentage of postictal language preservation occurred in right temporal seizures. Postictal aphasia and global disorientation predominated in left temporal seizures. EEG was important for lateralizing the epileptogenic lobe, specially considering rhythmic ictal activity and postictal findings.As crises epilépticas do lobo temporal tendem a seguir uma sequência previsível de eventos clínicos e eletrencefalográficos, cuja análise, preferencialmente através de sistemas de vídeo-EEG, sugere a localização e a lateralização do lobo epileptogênico. Para este estudo, foram analisadas 50 crises epilépticas do lobo temporal, do ponto de vista clínico e eletrencefalográfico, sendo 25 relacionadas a esclerose mesial (grupo 1 e 25 a patologias neocorticais (grupo 2. Auras abdominais foram as mais frequentes, predominando no grupo 1. Houve diferenças entre os dois grupos, quanto à instalação e duração da postura distônica, à postura tônica e à versão oculocefálica. Postura distônica unilateral foi o mais importante fenômeno clínico lateralizatório, sempre

  3. Function Lateralization via Measuring Coherence Laterality

    Science.gov (United States)

    Wang, Ze; Mechanic-Hamilton, Dawn; Pluta, John; Glynn, Simon; Detre, John A.

    2009-01-01

    A data-driven approach for lateralization of brain function based on the spatial coherence difference of functional MRI (fMRI) data in homologous regions-of-interest (ROI) in each hemisphere is proposed. The utility of using coherence laterality (CL) to determine function laterality was assessed first by examining motor laterality using normal subjects’ data acquired both at rest and with a simple unilateral motor task and subsequently by examining mesial temporal lobe memory laterality in normal subjects and patients with temporal lobe epilepsy. The motor task was used to demonstrate that CL within motor ROI correctly lateralized functional stimulation. In patients with unilateral epilepsy studied during a scene-encoding task, CL in a hippocampus-parahippocampus-fusiform (HPF) ROI was concordant with lateralization based on task activation, and the CL index (CLI) significantly differentiated the right side group to the left side group. By contrast, normal controls showed a symmetric HPF CLI distribution. Additionally, similar memory laterality prediction results were still observed using CL in epilepsy patients with unilateral seizures after the memory encoding effect was removed from the data, suggesting the potential for lateralization of pathological brain function based on resting fMRI data. A better lateralization was further achieved via a combination of the proposed approach and the standard activation based approach, demonstrating that assessment of spatial coherence changes provides a complementary approach to quantifying task-correlated activity for lateralizing brain function. PMID:19345736

  4. Compressed sensing cine imaging with high spatial or high temporal resolution for analysis of left ventricular function.

    Science.gov (United States)

    Goebel, Juliane; Nensa, Felix; Schemuth, Haemi P; Maderwald, Stefan; Gratz, Marcel; Quick, Harald H; Schlosser, Thomas; Nassenstein, Kai

    2016-08-01

    To assess two compressed sensing cine magnetic resonance imaging (MRI) sequences with high spatial or high temporal resolution in comparison to a reference steady-state free precession cine (SSFP) sequence for reliable quantification of left ventricular (LV) volumes. LV short axis stacks of two compressed sensing breath-hold cine sequences with high spatial resolution (SPARSE-SENSE HS: temporal resolution: 40 msec, in-plane resolution: 1.0 × 1.0 mm(2) ) and high temporal resolution (SPARSE-SENSE HT: temporal resolution: 11 msec, in-plane resolution: 1.7 × 1.7 mm(2) ) and of a reference cine SSFP sequence (standard SSFP: temporal resolution: 40 msec, in-plane resolution: 1.7 × 1.7 mm(2) ) were acquired in 16 healthy volunteers on a 1.5T MR system. LV parameters were analyzed semiautomatically twice by one reader and once by a second reader. The volumetric agreement between sequences was analyzed using paired t-test, Bland-Altman plots, and Passing-Bablock regression. Small differences were observed between standard SSFP and SPARSE-SENSE HS for stroke volume (SV; -7 ± 11 ml; P = 0.024), ejection fraction (EF; -2 ± 3%; P = 0.019), and myocardial mass (9 ± 9 g; P = 0.001), but not for end-diastolic volume (EDV; P = 0.079) and end-systolic volume (ESV; P = 0.266). No significant differences were observed between standard SSFP and SPARSE-SENSE HT regarding EDV (P = 0.956), SV (P = 0.088), and EF (P = 0.103), but for ESV (3 ± 5 ml; P = 0.039) and myocardial mass (8 ± 10 ml; P = 0.007). Bland-Altman analysis showed good agreement between the sequences (maximum bias ≤ -8%). Two compressed sensing cine sequences, one with high spatial resolution and one with high temporal resolution, showed good agreement with standard SSFP for LV volume assessment. J. Magn. Reson. Imaging 2016;44:366-374. © 2016 Wiley Periodicals, Inc.

  5. Bilingual language processing after a lesion in the left thalamic and temporal regions. A case report with early childhood onset

    International Nuclear Information System (INIS)

    van Lieshout, P.; Renier, W.; Eling, P.; de Bot, K.; Slis, I.

    1990-01-01

    This case study concerns an 18-year-old bilingual girl who suffered a radiation lesion in the left (dominant) thalamic and temporal region when she was 4 years old. Language and memory assessment revealed deficits in auditory short-term memory, auditory word comprehension, nonword repetition, syntactic processing, word fluency, and confrontation naming tasks. Both languages (English and Dutch) were found to be affected in a similar manner, despite the fact that one language (English) was acquired before and the other (Dutch) after the period of lesion onset. Most of the deficits appear to be related to verbal (short-term) memory dysfunction. Several hypotheses of subcortical involvement in memory processes are discussed with reference to existing theories in this area

  6. Top-down regulation of left temporal cortex by hypnotic amusia for rhythm: a pilot study on mismatch negativity.

    Science.gov (United States)

    Facco, Enrico; Ermani, Mario; Rampazzo, Patrizia; Tikhonoff, Valérie; Saladini, Marina; Zanette, Gastone; Casiglia, Edoardo; Spiegel, David

    2014-01-01

    To evaluate the effect of hypnotically induced amusia for rhythm (a condition in which individuals are unable to recognize melodies or rhythms) on mismatch negativity (MMN), 5 highly (HH) and 5 poorly (LH) hypnotizable nonmusician volunteers underwent MMN recording before and during a hypnotic suggestion for amusia. MMN amplitude was recorded using a 19-channel montage and then processed using the low-resolution electromagnetic tomography (LORETA) to localize its sources. MMN amplitude was significantly decreased during hypnotic amusia (p < .04) only in HH, where the LORETA maps of MMN showed a decreased source amplitude in the left temporal lobe, suggesting a hypnotic top-down regulation of activity of these areas and that these changes can be assessed by neurophysiological investigations.

  7. The relationship between enlargement of the temporal horns of the lateral ventricles and dementia in aging patients with Down syndrome

    International Nuclear Information System (INIS)

    LeMay, M.; Alvarez, N.

    1990-01-01

    Head CT studies of patients with Alzheimer's disease (AD) show global atrophic changes. Tissue loss is especially prominent in the temporal lobes, with widening of the temporal horns of the lateral ventricles and, usually, widening of the temporal sulci. Some recent studies have found a familial form of AD to be mapped to chromosome 21. Down syndrome (DS) results from the inheritance of three chromosomes 21, and it has been shown that after the age of 35 the brains of patients with DS commonly show neuropathological changes similar to those in patients with AD. CT studies of 25 patients with DS (ages 29-64 years) were examined for tissue loss in the temporal regions, and this was compared to the findings commonly seen in patients with AD. The widths of CSF spaces varied considerably in patients with DS, but after the age of 50 most of them showed significant widening of the temporal horns. In some patients the horns were large enough to suggest obstructive hydrocephalus. Because of a new trend toward deinstitutionalization of patients with DS, radiologists will be seeing more studies on these patients and should familiarize themselves with the unique ways in which they manifest the aging process. (orig.)

  8. Success of Anomia Treatment in Aphasia Is Associated With Preserved Architecture of Global and Left Temporal Lobe Structural Networks.

    Science.gov (United States)

    Bonilha, Leonardo; Gleichgerrcht, Ezequiel; Nesland, Travis; Rorden, Chris; Fridriksson, Julius

    2016-03-01

    Targeted speech therapy can lead to substantial naming improvement in some subjects with anomia following dominant-hemisphere stroke. We investigated whether treatment-induced improvement in naming is associated with poststroke preservation of structural neural network architecture. Twenty-four patients with poststroke chronic aphasia underwent 30 hours of speech therapy over a 2-week period and were assessed at baseline and after therapy. Whole brain maps of neural architecture were constructed from pretreatment diffusion tensor magnetic resonance imaging to derive measures of global brain network architecture (network small-worldness) and regional network influence (nodal betweenness centrality). Their relationship with naming recovery was evaluated with multiple linear regressions. Treatment-induced improvement in correct naming was associated with poststroke preservation of global network small worldness and of betweenness centrality in temporal lobe cortical regions. Together with baseline aphasia severity, these measures explained 78% of the variability in treatment response. Preservation of global and left temporal structural connectivity broadly explains the variability in treatment-related naming improvement in aphasia. These findings corroborate and expand on previous classical lesion-symptom mapping studies by elucidating some of the mechanisms by which brain damage may relate to treated aphasia recovery. Favorable naming outcomes may result from the intact connections between spared cortical areas that are functionally responsive to treatment. © The Author(s) 2015.

  9. Electrophysiological and auditory behavioral evaluation of individuals with left temporal lobe epilepsy Avaliação eletrofisiológica e comportamental da audição em individuos com epilepsia em lobo temporal esquerdo

    Directory of Open Access Journals (Sweden)

    Caroline Nunes Rocha

    2010-02-01

    Full Text Available The purpose of this study was to determine the repercussions of left temporal lobe epilepsy (TLE for subjects with left mesial temporal sclerosis (LMTS in relation to the behavioral test-Dichotic Digits Test (DDT, event-related potential (P300, and to compare the two temporal lobes in terms of P300 latency and amplitude. We studied 12 subjects with LMTS and 12 control subjects without LMTS. Relationships between P300 latency and P300 amplitude at sites C3A1,C3A2,C4A1, and C4A2, together with DDT results, were studied in inter-and intra-group analyses. On the DDT, subjects with LMTS performed poorly in comparison to controls. This difference was statistically significant for both ears. The P300 was absent in 6 individuals with LMTS. Regarding P300 latency and amplitude, as a group, LMTS subjects presented trend toward greater P300 latency and lower P300 amplitude at all positions in relation to controls, difference being statistically significant for C3A1 and C4A2. However, it was not possible to determine laterality effect of P300 between affected and unaffected hemispheres.O objetivo deste estudo foi determinar a repercussão da epilepsia de lobo temporal esquerdo (LTE em indivíduos com esclerose mesial temporal esquerda (EMTE em relação à avaliação auditiva comportamental-Teste Dicótico de Dígitos (TDD, ao Potencial Evocado Auditivo de Longa Latência (P300 e comparar o P300 do lobo temporal esquerdo e direito. Estudamos 12 indivíduos com EMTE (grupo estudo e 12 indivíduos controle com desenvolvimento típico. Analisamos as relações entre a latência e amplitude do P300, obtidos nas posições C3A1,C3A2,C4A1 e C4A2 e os resultados obtidos no TDD. No TDD, o grupo estudo apresentou pior desempenho em relação ao grupo controle, sendo esta diferença estatisticamente significante em ambas as orelhas. Para o P300, observamos que em seis indivíduos com EMTE o potencial foi ausente. Para a latência e amplitude, verificamos que estes

  10. Altered Connectivity of the Anterior Cingulate and the Posterior Superior Temporal Gyrus in a Longitudinal Study of Later-life Depression

    Directory of Open Access Journals (Sweden)

    Kenichiro Harada

    2018-02-01

    Full Text Available Patients with later-life depression (LLD show abnormal gray matter (GM volume, white matter (WM integrity and functional connectivity in the anterior cingulate cortex (ACC and posterior superior temporal gyrus (pSTG, but it remains unclear whether these abnormalities persist over time. We examined whether structural and functional abnormalities in these two regions are present within the same subjects during depressed vs. remitted phases. Sixteen patients with LLD and 30 healthy subjects were studied over a period of 1.5 years. Brain images obtained with a 3-Tesla magnetic resonance imaging (MRI system were analyzed by voxel-based morphometry of the GM volume, and diffusion tensor imaging (DTI and resting-state functional MRI were used to assess ACC–pSTG connectivity. Patients with LLD in the depressed and remitted phases showed significantly smaller GM volume in the left ACC and left pSTG than healthy subjects. Both patients with LLD in the depressed and remitted phases had significantly higher diffusivities in the WM tract of the left ACC–pSTG than healthy subjects. Remitted patients with LLD showed lower functional ACC–pSTG connectivity compared to healthy subjects. No difference was found in the two regions between depressed and remitted patients in GM volume, structural or functional connectivity. Functional ACC–pSTG connectivity was positively correlated with lower global function during remission. Our preliminary data show that structural and functional abnormalities of the ACC and pSTG occur during LLD remission. Our findings tentatively reveal the brain pathophysiology involved in LLD and may aid in developing neuroanatomical biomarkers for this condition.

  11. Altered Connectivity of the Anterior Cingulate and the Posterior Superior Temporal Gyrus in a Longitudinal Study of Later-life Depression.

    Science.gov (United States)

    Harada, Kenichiro; Ikuta, Toshikazu; Nakashima, Mami; Watanuki, Toshio; Hirotsu, Masako; Matsubara, Toshio; Yamagata, Hirotaka; Watanabe, Yoshifumi; Matsuo, Koji

    2018-01-01

    Patients with later-life depression (LLD) show abnormal gray matter (GM) volume, white matter (WM) integrity and functional connectivity in the anterior cingulate cortex (ACC) and posterior superior temporal gyrus (pSTG), but it remains unclear whether these abnormalities persist over time. We examined whether structural and functional abnormalities in these two regions are present within the same subjects during depressed vs. remitted phases. Sixteen patients with LLD and 30 healthy subjects were studied over a period of 1.5 years. Brain images obtained with a 3-Tesla magnetic resonance imaging (MRI) system were analyzed by voxel-based morphometry of the GM volume, and diffusion tensor imaging (DTI) and resting-state functional MRI were used to assess ACC-pSTG connectivity. Patients with LLD in the depressed and remitted phases showed significantly smaller GM volume in the left ACC and left pSTG than healthy subjects. Both patients with LLD in the depressed and remitted phases had significantly higher diffusivities in the WM tract of the left ACC-pSTG than healthy subjects. Remitted patients with LLD showed lower functional ACC-pSTG connectivity compared to healthy subjects. No difference was found in the two regions between depressed and remitted patients in GM volume, structural or functional connectivity. Functional ACC-pSTG connectivity was positively correlated with lower global function during remission. Our preliminary data show that structural and functional abnormalities of the ACC and pSTG occur during LLD remission. Our findings tentatively reveal the brain pathophysiology involved in LLD and may aid in developing neuroanatomical biomarkers for this condition.

  12. The central retinal artery occlusion in the right eye followed by a branch retinal artery occlusion in the left eye four days later

    Directory of Open Access Journals (Sweden)

    Cagatay Caglar

    2013-01-01

    Full Text Available A 65-year-old woman was admitted to our clinic with complaints of sudden, painless, decrease in vision, and sectoral visual field defect in the left eye and later presented to our clinic again with a history of sudden loss of vision in her right eye. In this case study we reported that the patient had branch retinal artery occlusion (BRAO in the left eye and at the same time progressing central retinal artery occlusion (CRAO in the right eye.

  13. Mapping auditory core, lateral belt, and parabelt cortices in the human superior temporal gyrus

    DEFF Research Database (Denmark)

    Sweet, Robert A; Dorph-Petersen, Karl-Anton; Lewis, David A

    2005-01-01

    The goal of the present study was to determine whether the architectonic criteria used to identify the core, lateral belt, and parabelt auditory cortices in macaque monkeys (Macaca fascicularis) could be used to identify homologous regions in humans (Homo sapiens). Current evidence indicates...

  14. Differentiation of the lateral compartment of the cochlea requires a temporally restricted FGF20 signal.

    Directory of Open Access Journals (Sweden)

    Sung-Ho Huh

    2012-01-01

    Full Text Available A large proportion of age-related hearing loss is caused by loss or damage to outer hair cells in the organ of Corti. The organ of Corti is the mechanosensory transducing apparatus in the inner ear and is composed of inner hair cells, outer hair cells, and highly specialized supporting cells. The mechanisms that regulate differentiation of inner and outer hair cells are not known. Here we report that fibroblast growth factor 20 (FGF20 is required for differentiation of cells in the lateral cochlear compartment (outer hair and supporting cells within the organ of Corti during a specific developmental time. In the absence of FGF20, mice are deaf and lateral compartment cells remain undifferentiated, postmitotic, and unresponsive to Notch-dependent lateral inhibition. These studies identify developmentally distinct medial (inner hair and supporting cells and lateral compartments in the developing organ of Corti. The viability and hearing loss in Fgf20 knockout mice suggest that FGF20 may also be a deafness-associated gene in humans.

  15. Escape tectonism in the Gulf of Thailand: Paleogene left-lateral pull-apart rifting in the Vietnamese part of the Malay Basin

    DEFF Research Database (Denmark)

    Fyhn, Michael B.W.; Boldreel, Lars Ole; Nielsen, Lars H

    2010-01-01

    The Malay Basin represents one of the largest rift basins of SE Asia. Based on a comprehensive 2-D seismic database tied to wells covering mainly Vietnamese acreage, the evolution of the Vietnamese part of the basin is outlined and a new tectonic model is proposed for the development of the basin....... The Vietnamese part of the Malay Basin comprises a large and deep Paleogene pull-apart basin formed through Middle or Late Eocene to Oligocene left-lateral strike-slip along NNW-trending fault zones. The Tho Chu Fault Zone constitutes a significant Paleogene left-lateral strike-slip zone most likely associated......–Strending faults in the central part of the basin. However, the lack of inversion in Vietnamese territory only seems to merit a few kilometers of dextral inversion....

  16. Study of the lateral and temporal distributions of particles in the extensive air shower front

    International Nuclear Information System (INIS)

    Toma, G.; Brancus, I. M.; Mitrica, B.; Badea, A. F.; Rebel, H.; Haungs, A.; Sima, O.

    2004-01-01

    To understand the influence of the primary particle (mass and energy) on the development of the Extensive Air Showers (EAS) a study has been performed on simulated events. A number of showers have been simulated using CORSIKA simulation program for different primary particles (p, C, Fe) and different energies (5.62x10 16 and 10 17 eV). The arrival time distributions of particles arriving at ground (detector level) have been studied for different primary energies and masses. Arrival time quartiles have been calculated and compared for different primaries. Arrival time distributions for different distances to shower core and different threshold energies have been compared. To obtain information about the influence of the primary particle on the shape of the lateral distribution of detected shower particles, the simulated lateral density distribution has been approximated with a parametric Lateral Density Function (LDF). The interaction of the shower particles with the detectors has been simulated and the energy deposited in the detectors has been evaluated. This method was used for obtaining the reconstructed (equivalent to the experimental) lateral density distribution, afterwards approximated with the same LDF. To check the quality of the fit and to investigate the sensitivity to fitting conditions, the study was done for three radial ranges, 40-200 m, 350-650 m, 0-1000 m. The total number of particles in the shower front and the truncated number of particles (in the fitting range) have been reconstructed to be compared with the real number of particles from CORSIKA simulations and to investigate the potential use of these parameters in a multiparametric study of extensive air showers. (authors)

  17. Temporal Entropy Generation in the Viscous Layers of Laterally-converging Duct Flows

    International Nuclear Information System (INIS)

    McEligot, Donald M.; Brodkey, Robert S.; Eckelmann, Helmut

    2008-01-01

    Since insight into entropy generation is a key to increasing efficiency and thereby reducing fuel consumption and/or waste and--for wall-bounded flows--most entropy is generated in the viscous layer, we examine the transient behavior of its dominant contributor there for a non-canonical flow. New measurements in oil flow are presented for the effects of favorable streamwise mean pressure gradients on temporal entropy generation rates and, in the process, on key Reynolds-stress-producing events such as sweep front passage and on the deceleration/outflow phase of the overall bursting process. Two extremes have been considered: (1) a high pressure gradient, nearing 'laminarization', and (2), for comparison, a low pressure gradient corresponding to many earlier experiments. In both cases, the peak temporal entropy generation rate occurs shortly after passage of the ejection/sweep interface. Whether sweep and ejection rates appear to decrease or increase with the pressure gradient depends on the feature examined and the manner of sampling. When compared using wall coordinates for velocities, distances and time, the trends and magnitudes of the transient behaviors are mostly the same. The main effects of the higher pressure gradient are (1) changes in the time lag between detections--representing modification of the shape of the sweep front and the sweep angle with the wall, (2) modification of the magnitude of an instantaneous Reynolds shear stress with wall distance and (3) enlarging the sweeps and ejections. Results new for both low and high pressure gradients are the temporal behaviors of the dominant contribution to entropy generation; it is found to be much more sensitive to distance from the wall than to streamwise pressure gradient

  18. Selective hypertrophy of the lobus caudatus as a novel approach enabling extended right hepatectomy in the presence of a non-perfused left lateral liver lobe.

    Science.gov (United States)

    Atanasov, Georgi; Schmelzle, Moritz; Thelen, Armin; Wiltberger, Georg; Hau, Hans-Michael; Krenzien, Felix; Petersen, Tim-Ole; Moche, Michael; Jonas, Sven

    2014-08-01

    Portal vein embolization (PVE) is a well-established technique to enhance functional hepatic reserves of segments II and III before curative extended right hepatectomy for tumors of the right liver lobe. However, an adequate hepatopetal flow of the left lateral portal vein branches is required for a sufficient PVE-associated hypertrophy. Here, we report a 65-year old patient suffering from a locally advanced intrahepatic cholangiocarcinoma in the right liver lobe and segment IV. A curative extended right hepatectomy after preoperative PVE of liver segments IV-VIII was initially impossible because of partial thrombosis of the left lateral portal vein branches resulting in an ischemic-type atrophy of segments II and III. However, due to a massive hypertrophy of the caudate lobe following PVE of liver segments IV-VIII, subsequent extended right hepatectomy with intraoperative thrombectomy of segments II and III was made possible. To our knowledge this is the first case in which an extended right hepatectomy for a liver malignancy, in the presence of atrophic left lateral section, was made possible by a massive PVE-associated hypertrophy of the caudate lobe.

  19. Cerebral and cerebellar language organization in a right-handed subject with a left temporal porencephalic cyst : An fMRI study

    NARCIS (Netherlands)

    De Coninck, Mattias; Van Hecke, Wim; Crols, Roe; van Dun, Kim; Van Dam, Debby; De Deyn, Peter P.; Brysbaert, Marc; Marien, Peter

    To test the hypothesis of crossed cerebro-cerebellar language dominance (Marien, Engelborghs, Fabbro, & De Deyn, 2001) in atypical populations, the pattern of cerebral and cerebellar language organization in a right-handed woman with a large porencephalic cyst in the left temporal lobe with no

  20. Analysis of the asymmetrically expressed Ablim1 locus reveals existence of a lateral plate Nodal-independent left sided signal and an early, left-right independent role for nodal flow

    Directory of Open Access Journals (Sweden)

    Hilton Helen

    2010-05-01

    Full Text Available Abstract Background Vertebrates show clear asymmetry in left-right (L-R patterning of their organs and associated vasculature. During mammalian development a cilia driven leftwards flow of liquid leads to the left-sided expression of Nodal, which in turn activates asymmetric expression of the transcription factor Pitx2. While Pitx2 asymmetry drives many aspects of asymmetric morphogenesis, it is clear from published data that additional asymmetrically expressed loci must exist. Results A L-R expression screen identified the cytoskeletally-associated gene, actin binding lim protein 1 (Ablim1, as asymmetrically expressed in both the node and left lateral plate mesoderm (LPM. LPM expression closely mirrors that of Nodal. Significantly, Ablim1 LPM asymmetry was detected in the absence of detectable Nodal. In the node, Ablim1 was initially expressed symmetrically across the entire structure, resolving to give a peri-nodal ring at the headfold stage in a flow and Pkd2-dependent manner. The peri-nodal ring of Ablim1 expression became asymmetric by the mid-headfold stage, showing stronger right than left-sided expression. Node asymmetry became more apparent as development proceeded; expression retreated in an anticlockwise direction, disappearing first from the left anterior node. Indeed, at early somite stages Ablim1 shows a unique asymmetric expression pattern, in the left lateral plate and to the right side of the node. Conclusion Left LPM Ablim1 is expressed in the absence of detectable LPM Nodal, clearly revealing existence of a Pitx2 and Nodal-independent left-sided signal in mammals. At the node, a previously unrecognised action of early nodal flow and Pkd2 activity, within the pit of the node, influences gene expression in a symmetric manner. Subsequent Ablim1 expression in the peri-nodal ring reveals a very early indication of L-R asymmetry. Ablim1 expression analysis at the node acts as an indicator of nodal flow. Together these results make

  1. Left ventricular filling pressure by septal and lateral E/e' equally predict cardiovascular events in the general population

    DEFF Research Database (Denmark)

    Wang, Joanna Nan; Biering-Sørensen, Tor; Jørgensen, Peter Godsk

    2017-01-01

    /e'lateral were equally strong predictors of cardiac events; in age- and sex-adjusted models they did not differ in AUC (septal: 0.8385, lateral: 0.8389; p = 0.94) or in continuous NRI (p = 0.84). Models using E/e'average did not improve AUC or NRI, and the intra-individual difference between sites had...... no predictive value (p = 0.79). E/e'septal was generally higher than E/e'lateral, thus age- and sex-specific normal values were reported for both sites for a population free of cardiac events during 10 years of follow-up. CONCLUSIONS: Septal and lateral E/e' are equally useful in predicting cardiac events...

  2. Application of T2 relaxometry in lateralization and localization of mesial temporal lobe epilepsy and corresponding comparison with MR volumetry.

    Science.gov (United States)

    Chen, Hui; Yu, Guilian; Wang, Jiangtao; Li, Feng; Li, Guangming

    2016-09-01

    Magnetic resonance (MR) volumetry is insensitive to subtle mesial temporal sclerosis (MTS), while T2 relaxometry is potential useful in detecting MTS, especially MTS in early course. To explore and compare the feasibility of T2 relaxometry and MR volumetry in evaluation of mesial temporal lobe epilepsy (MTLE) and lateralization of the epileptogenic zone, so as to optimize and enhance lesion depiction. For the 17 unilateral MTLE patients and 14 normal participants, the hippocampus and amygdala were contoured on axial T2-weighted (T2W) images and then co-registered onto T2 relaxation maps. Abnormal is defined as an elevated asymmetric ratio of larger than 2 SD. Visual and quantitative volumetric assessment were combined as outcomes of MR volumetry to distinguish MR-positive and MR-negative lesions. Operative and pathological findings were used as gold standard. T2 values of lesions were significantly elevated. In lateralizing the epileptogenic zones, T2 relaxometry yielded an overall accuracy of 94.1% (sensitivity 92.6%, specificity 100%), and MR volumetry yielded an overall accuracy of 82.4% (sensitivity 88.9%, specificity 57.1%), meaning a better performance of T2 relaxometry (P volumetry. MR volumetry wrongly discerned three normal regions as MTS, while one MR-negative sclerotic hippocampus was detected by T2 relaxometry. T2 relaxometry is feasible in non-invasive lateralization of epileptogenic zone, and more advantaged than MR volumetry in detecting MR-negative lesions, facilitating prompt diagnosis and longitudinal disease monitoring. © The Foundation Acta Radiologica 2015.

  3. Cerebral lateralization of the face-cortical network in left-handers: only the FFA does not get it right

    OpenAIRE

    Bukowski, Henryk; Rossion, Bruno; Schiltz, Christine; Hanseeuw; Dricot, Laurence

    2010-01-01

    Face processing is a function that is highly lateralized in humans, as supported by original evidence from brain lesion studies (Hecaen & Anguerlergues, 1962), followed by studies using divided visual field presentations (Heller & Levy, 1981), neuroimaging (Sergent et al., 1992) and event-related potentials (Bentin et al., 1996). Studies in non-human primates (Perrett et al., 1988; Zangenehpour & Chaudhuri, 2005), or other mammals (Peirce & Kendrick, 2001) support the right lateralization of ...

  4. Cosmetic appreciation of lateralization of peripheral facial palsy: 'preference for left or right, true or mirror image?'.

    Science.gov (United States)

    Pouwels, Sjaak; Ingels, Koen; van Heerbeek, Niels; Beurskens, Carien

    2014-09-01

    There have been several studies in the past depicting asymmetry in 'normal' human faces. Evidence supports the fact that the right hemisphere is superior in the recognition of emotions expressed by the human face and indicates a right hemispheric specialization for processing emotional information. The primary aim of this study is to determine whether there is a difference in cosmetic appreciation of a left peripheral facial palsy compared to a right peripheral facial palsy? Pictures of patients with a facial palsy with House-Brackmann II-VI were reversed as a mirror image and offered as a pair of pictures, together with the true image. Forty-two patients and 24 medical professionals familiar with facial palsy were asked to choose the most attractive photograph. The primary 'end' point was the most attractive side in the pictures chosen by medical professionals and patients. The secondary 'end' points consisted of the preferences for the mirror or true image, and influences of the House-Brackmann score and age. Medical professionals preferred the photographs from patients with a right and left peripheral facial palsy (PFP) in, respectively, a mean of 44 % (41-48 %) and 56 % (52-59 %) of the pictures (p = 0.02). When comparing mirror and true image, patients with a left-sided facial palsy chose their mirror and true image as most attractive in 90 and 10 %, respectively (p 0.05). Subanalysis of patients with a PFP House-Brackmann score V and VI showed that medical professionals did not have a significant preference for a left nor right-sided facial palsy. Patients with a left-sided facial palsy chose their mirror image in all cases and patients with a right-sided palsy chose their mirror and true image in resp. 33 and 67 %. The House-Brackmann score (p = 0.52) and age (p = 0.73) of the patients did not influence preferences. This study, demonstrating that medical professionals find a right-sided facial palsy cosmetically less attractive than a left-sided, has

  5. A method for the automated assessment of temporal characteristics of functional hemispheric lateralization by transcranial Doppler sonography.

    Science.gov (United States)

    Deppe, M; Knecht, S; Lohmann, H; Ringelstein, E B

    2004-07-01

    Transcranial Doppler sonography (TCD) can guide and complement investigations based on functional magnetic resonance and positron emission tomography imaging by providing continuous information on cerebral perfusion changes correlated to cerebral activation. So far, however, the role of functional TCD has been limited by a lack of sensitivity. Here, the authors present an outline of a method that increases the potential of TCD to detect perfusion changes within a vascular territory. Sensitivity on the order of 1% can be achieved by transformation of Doppler envelope curves, which accounts for systemic quasi-periodic and irregular spontaneous blood flow modulations and artificial disturbances related to the recording. A statistical technique is introduced that allows the automatic detection of time periods of significant hemispheric lateralization in evoked flow studies. Furthermore, an index of laterality is defined quantifying the extent of hemispheric dominance during stimulus processing. The analysis technique described in this article has been successfully employed in recent examinations on vision, motor activation, language, language recovery, and other cognitive tasks. The novel functional TCD technique permits valid and reproducible assessments of the temporal characteristics of functional hemispheric lateralization.

  6. Coronary perfusion pressure and compression quality in maternal cardiopulmonary resuscitation in supine and left-lateral tilt positions: A prospective, crossover study using mannequins and swine models.

    Science.gov (United States)

    Dohi, Satoshi; Ichizuka, Kiyotake; Matsuoka, Ryu; Seo, Kohei; Nagatsuka, Masaaki; Sekizawa, Akihiko

    2017-09-01

    The risk of maternal and fetal mortality is high if cardiopulmonary arrest occurs during pregnancy. To assess the best position for maternal cardiopulmonary resuscitation (CPR), a prospective randomized crossover study was undertaken, involving basic life support mannequin-based simulation (BLS-MS) and a swine model of pulseless electrical activity (an unstable cardiac state) incorporating a fetal mannequin (PEA-FM). The BLS-MS (performed by certified rescuers) served to evaluate the quality of chest compressions in 30° left lateral tilt (LLT) and supine positions. Based on a 5-point scale, each rescuer subjectively graded their experience. The PEA-FM model was used to compare coronary perfusion pressure readings during CPR in supine, supine with left uterine displacement, 30° LLT, and 30° right lateral tilt positions. Compression rate and correctness of hand position, compression depth, and recoil were measures of compression quality (BLS-MS). Compared with LLT position, supine position enabled correct hand position (rate: 0.99 vs 0.88; p<0.05) and compression depth (rate: 0.76 vs 0.36; p<0.001) significantly more often. Moreover, BLS-MS rescuers found chest compressions significantly easier to perform with the mannequin in supine (vs LLT) position (difficulty score: 1.75 vs 3.95; p<0.001). In the PEA-FM study arm, supine position with left uterine displacement and right lateral tilt positions had the highest and lowest recorded coronary perfusion pressure readings, respectively. Supine position with left uterine displacement is optimal for maternal CPR. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

  7. Network-wise cerebral blood flow redistribution after 20 Hz rTMS on left dorso-lateral prefrontal cortex.

    Science.gov (United States)

    Shang, Yuan-Qi; Xie, Jun; Peng, Wei; Zhang, Jian; Chang, Da; Wang, Ze

    2018-04-01

    The repetitive application of transcranial magnetic stimulation (rTMS) on left dorsolateral prefrontal cortex (DLPFC) has been consistently shown to be beneficial for treating various neuropsychiatric or neuropsychological disorders, but its neural mechanisms still remain unclear. The purpose of this study was to measure the effects of high-frequency left DLPFC rTMS using cerebral blood flow (CBF) collected from 40 young healthy subjects before and after applying 20 Hz left DLPFC rTMS or SHAM stimulations. Relative CBF (rCBF) changes before and after 20 Hz rTMS or SHAM were assessed with paired-t test. The results show that 20 Hz DLPFC rTMS induced CBF redistribution in the default mode network, including increased rCBF in left medial temporal cortex (MTC)/hippocampus, but reduced rCBF in precuneus and cerebellum. Meanwhile, SHAM stimulation didn't produce any rCBF changes. After controlling SHAM effects, only the rCBF increase in MTC/hippocampus remained. Those data suggest that the beneficial effects of high-frequency rTMS may be through a within-network rCBF redistribution. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. The lateralized arcuate fasciculus in developmental pitch disorders among mandarin amusics: left for speech and right for music.

    Science.gov (United States)

    Chen, Xizhuo; Zhao, Yanxin; Zhong, Suyu; Cui, Zaixu; Li, Jiaqi; Gong, Gaolang; Dong, Qi; Nan, Yun

    2018-05-01

    The arcuate fasciculus (AF) is a neural fiber tract that is critical to speech and music development. Although the predominant role of the left AF in speech development is relatively clear, how the AF engages in music development is not understood. Congenital amusia is a special neurodevelopmental condition, which not only affects musical pitch but also speech tone processing. Using diffusion tensor tractography, we aimed at understanding the role of AF in music and speech processing by examining the neural connectivity characteristics of the bilateral AF among thirty Mandarin amusics. Compared to age- and intelligence quotient (IQ)-matched controls, amusics demonstrated increased connectivity as reflected by the increased fractional anisotropy in the right posterior AF but decreased connectivity as reflected by the decreased volume in the right anterior AF. Moreover, greater fractional anisotropy in the left direct AF was correlated with worse performance in speech tone perception among amusics. This study is the first to examine the neural connectivity of AF in the neurodevelopmental condition of amusia as a result of disrupted music pitch and speech tone processing. We found abnormal white matter structural connectivity in the right AF for the amusic individuals. Moreover, we demonstrated that the white matter microstructural properties of the left direct AF is modulated by lexical tone deficits among the amusic individuals. These data support the notion of distinctive pitch processing systems between music and speech.

  9. Rapid-Sequence Intubation in the Left-Lateral Tilt Position in a Pregnant Woman with Premature Placental Abruption Utilizing a Videolaryngoscope

    Directory of Open Access Journals (Sweden)

    Kenta Nakao

    2015-04-01

    Full Text Available Case - A 24-year-old pregnant woman was admitted to our hospital with decreased fetal heart rate. Obstetric examination revealed premature placental abruption; emergent caesarean section was planned under general anesthesia. On entering the operating room, the patient showed severe vital sign deterioration (blood pressure, 75/45 mm Hg; heart rate, 142 beats per minute. As left uterine displacement may worsen the premature placental abruption, the patient was placed in the left-lateral tilt position by rotating the operating table to release compression on the inferior vena cava by theuterus. To avoid circulatory collapse, rapid-sequence intubation was performed in this position. Tracheal intubation was performed with the Pentax-AWS Airwayscope (AWS videolaryngoscope, AWS; HOYA, Japan to obtain a good laryngeal view and minimize stress from laryngoscopy. After sufficient oxygenation, 120 mg of thiopental was administered. A second anesthesiologist performed cricoid pressure and 50 mg of rocuronium was administered after confirming loss of consciousness. This was followed by insertion of the AWS with a thin intlock into the mouth. Tracheal intubation was performed uneventfully. Discussion - Rapid-sequence intubation in the left-lateral tilted position with the AWS videolaryngoscope may be beneficial for pregnant women with vital sign deterioration.

  10. Left atrial appendage segmentation and quantitative assisted diagnosis of atrial fibrillation based on fusion of temporal-spatial information.

    Science.gov (United States)

    Jin, Cheng; Feng, Jianjiang; Wang, Lei; Yu, Heng; Liu, Jiang; Lu, Jiwen; Zhou, Jie

    2018-05-01

    In this paper, we present an approach for left atrial appendage (LAA) multi-phase fast segmentation and quantitative assisted diagnosis of atrial fibrillation (AF) based on 4D-CT data. We take full advantage of the temporal dimension information to segment the living, flailed LAA based on a parametric max-flow method and graph-cut approach to build 3-D model of each phase. To assist the diagnosis of AF, we calculate the volumes of 3-D models, and then generate a "volume-phase" curve to calculate the important dynamic metrics: ejection fraction, filling flux, and emptying flux of the LAA's blood by volume. This approach demonstrates more precise results than the conventional approaches that calculate metrics by area, and allows for the quick analysis of LAA-volume pattern changes of in a cardiac cycle. It may also provide insight into the individual differences in the lesions of the LAA. Furthermore, we apply support vector machines (SVMs) to achieve a quantitative auto-diagnosis of the AF by exploiting seven features from volume change ratios of the LAA, and perform multivariate logistic regression analysis for the risk of LAA thrombosis. The 100 cases utilized in this research were taken from the Philips 256-iCT. The experimental results demonstrate that our approach can construct the 3-D LAA geometries robustly compared to manual annotations, and reasonably infer that the LAA undergoes filling, emptying and re-filling, re-emptying in a cardiac cycle. This research provides a potential for exploring various physiological functions of the LAA and quantitatively estimating the risk of stroke in patients with AF. Copyright © 2018 Elsevier Ltd. All rights reserved.

  11. A conceptual lemon: theta burst stimulation to the left anterior temporal lobe untangles object representation and its canonical color.

    Science.gov (United States)

    Chiou, Rocco; Sowman, Paul F; Etchell, Andrew C; Rich, Anina N

    2014-05-01

    Object recognition benefits greatly from our knowledge of typical color (e.g., a lemon is usually yellow). Most research on object color knowledge focuses on whether both knowledge and perception of object color recruit the well-established neural substrates of color vision (the V4 complex). Compared with the intensive investigation of the V4 complex, we know little about where and how neural mechanisms beyond V4 contribute to color knowledge. The anterior temporal lobe (ATL) is thought to act as a "hub" that supports semantic memory by integrating different modality-specific contents into a meaningful entity at a supramodal conceptual level, making it a good candidate zone for mediating the mappings between object attributes. Here, we explore whether the ATL is critical for integrating typical color with other object attributes (object shape and name), akin to its role in combining nonperceptual semantic representations. In separate experimental sessions, we applied TMS to disrupt neural processing in the left ATL and a control site (the occipital pole). Participants performed an object naming task that probes color knowledge and elicits a reliable color congruency effect as well as a control quantity naming task that also elicits a cognitive congruency effect but involves no conceptual integration. Critically, ATL stimulation eliminated the otherwise robust color congruency effect but had no impact on the numerical congruency effect, indicating a selective disruption of object color knowledge. Neither color nor numerical congruency effects were affected by stimulation at the control occipital site, ruling out nonspecific effects of cortical stimulation. Our findings suggest that the ATL is involved in the representation of object concepts that include their canonical colors.

  12. MEG evidence for conceptual combination but not numeral quantification in the left anterior temporal lobe during language production

    Directory of Open Access Journals (Sweden)

    Paul eDel Prato

    2014-06-01

    Full Text Available The left anterior temporal lobe (LATL has risen as a leading candidate for a brain locus of composition in language; yet the computational details of its function are unknown. Although most literature discusses it as a combinatory region in very general terms, it has also been proposed to reflect the more specific function of conceptual combination, which in the classic use of this term mainly pertains to the combination of open class words with obvious conceptual contributions. We aimed to distinguish between these two possibilities by contrasting plural nouns in contexts where they were either preceded by a color modifier (red cups, eliciting conceptual combination, or by a number word (two cups, eliciting numeral quantification but no conceptual combination. This contrast was chosen because within a production task, it allows the manipulation of composition type while keeping the physical stimulus constant: a display of two red cups can be named as two cups or red cups depending on the task instruction. These utterances were compared to productions of two-word number and color lists, intended as noncombinatory control conditions. MEG activity was recorded during the planning for production, prior to motion artifacts. As expected on the basis of comprehension studies, color modification elicited increased LATL activity as compared to color lists, demonstrating that this basic combinatory effect is strongly crossmodal. However, numeral quantification did not elicit a parallel effect, suggesting that the function of the LATL is (i semantic and not syntactic (given that both color modification and numeral quantification involve syntactic composition and (ii corresponds more closely to the classical psychological notion of conceptual combination as opposed to a more general semantic combinatory function.

  13. A comparison of brain activity associated with language production in brain tumor patients with left and right sided language laterality

    NARCIS (Netherlands)

    Jansma, J. M.; Ramsey, N.; Rutten, G.J.M.

    2015-01-01

    Aim. Language dominance is an important factor for clinical decision making in brain tumor surgery. Functional MM can provide detailed information about the organization of language in the brain. One often used measure derived from fMRI data is the laterality index (LI). The LI is typically based on

  14. Positive schizotypy scores correlate with left visual field interference for negatively valenced emotional words: A lateralized emotional stroop study

    NARCIS (Netherlands)

    Strien, J.W.; van Kampen, D.

    2010-01-01

    Fourteen men scoring high and 14 men scoring low on a positive schizotypy scale participated in a lateralized emotional Stroop task. Vocal reaction times for color naming of neutral, positive and negative emotional words were recorded. Across participants, the color naming of neutral and emotional

  15. Temporal Fine-Structure Coding and Lateralized Speech Perception in Normal-Hearing and Hearing-Impaired Listeners

    DEFF Research Database (Denmark)

    Locsei, Gusztav; Pedersen, Julie Hefting; Laugesen, Søren

    2016-01-01

    This study investigated the relationship between speech perception performance in spatially complex, lateralized listening scenarios and temporal fine-structure (TFS) coding at low frequencies. Young normal-hearing (NH) and two groups of elderly hearing-impaired (HI) listeners with mild or moderate...... hearing loss above 1.5 kHz participated in the study. Speech reception thresholds (SRTs) were estimated in the presence of either speech-shaped noise, two-, four-, or eight-talker babble played reversed, or a nonreversed two-talker masker. Target audibility was ensured by applying individualized linear...... threshold nor the interaural phase difference threshold tasks showed a correlation with the SRTs or with the amount of masking release due to binaural unmasking, respectively. The results suggest that, although HI listeners with normal hearing thresholds below 1.5 kHz experienced difficulties with speech...

  16. Repeated measurements of cerebral blood flow in the left superior temporal gyrus reveal tonic hyperactivity in patients with auditory verbal hallucinations: A possible trait marker

    Directory of Open Access Journals (Sweden)

    Philipp eHoman

    2013-06-01

    Full Text Available Background: The left superior temporal gyrus (STG has been suggested to play a key role in auditory verbal hallucinations in patients with schizophrenia. Methods: Eleven medicated subjects with schizophrenia and medication-resistant auditory verbal hallucinations and 19 healthy controls underwent perfusion magnetic resonance imaging with arterial spin labeling. Three additional repeated measurements were conducted in the patients. Patients underwent a treatment with transcranial magnetic stimulation (TMS between the first 2 measurements. The main outcome measure was the pooled cerebral blood flow (CBF, which consisted of the regional CBF measurement in the left superior temporal gyrus (STG and the global CBF measurement in the whole brain.Results: Regional CBF in the left STG in patients was significantly higher compared to controls (p < 0.0001 and to the global CBF in patients (p < 0.004 at baseline. Regional CBF in the left STG remained significantly increased compared to the global CBF in patients across time (p < 0.0007, and it remained increased in patients after TMS compared to the baseline CBF in controls (p < 0.0001. After TMS, PANSS (p = 0.003 and PSYRATS (p = 0.01 scores decreased significantly in patients.Conclusions: This study demonstrated tonically increased regional CBF in the left STG in patients with schizophrenia and auditory hallucinations despite a decrease in symptoms after TMS. These findings were consistent with what has previously been termed a trait marker of auditory verbal hallucinations in schizophrenia.

  17. Experimental study of essential hypertension related to neurovascular compression established by fixation of balloon at the left lateral medulla

    International Nuclear Information System (INIS)

    Shen Jialin; Xu Jianrong; Luo Qizhong; Zhang Xiaohua; Li Shanquan; Chen Kemin

    2002-01-01

    Objective: To explore the possible mechanisms of neurogenic hypertension. Methods: With the guide of modern imaging, the hypertensive animal model of pulsatile neurovascular compression was established by fixation of balloon at the entry zone of the ninth and tenth cranial nerves of the left ventrolateral medulla oblongata. Blood pressure and heart rate data were collected at preoperation and one hour, 2 weeks, 4 weeks, and 6 weeks of postoperation. Results: The results showed that SBP at postoperation rose by 27.3%, 26.1%, 25.4% and 27.4%, respectively; DBP rose by 18.8%, 20.8%, 20.0% and 20.2%, respectively; MAP rose by 24.2%, 24.1%, 23.2% and 24.8%, respectively; HR rose by 34.9%, 26.7%, 26.9% and 26.1% respectively. Statistically, SBP, DAP, MAP and HR of postoperation significantly increased compared with that of preoperation in hypertension group (F = 9.044, 12,679, 11.306, 16.536, P 0.05). Conclusion: Essential hypertension may by caused by neurovascular compression of ninth and tenth cranial nerves of the left ventrolateral medulla oblongata at the REZ

  18. Alteration of Interictal Brain Activity in Patients with Temporal Lobe Epilepsy in the Left Dominant Hemisphere: A Resting-State MEG Study

    Directory of Open Access Journals (Sweden)

    Haitao Zhu

    2014-01-01

    Full Text Available Resting MEG activities were compared between patients with left temporal lobe epilepsy (LTLE and normal controls. Using SAMg2, the activities of MEG data were reconstructed and normalized. Significantly elevated SAMg2 signals were found in LTLE patients in the left temporal lobe and medial structures. Marked decreases of SAMg2 signals were found in the wide extratemporal lobe regions, such as the bilateral visual cortex. The study also demonstrated a positive correlation between the seizure frequency and brain activities of the abnormal regions after the multiple linear regression analysis. These results suggested that the aberrant brain activities not only were related to the epileptogenic zones, but also existed in other extratemporal regions in patients with LTLE. The activities of the aberrant regions could be further damaged with the increase of the seizure frequency. Our findings indicated that LTLE could be a multifocal disease, including complex epileptic networks and brain dysfunction networks.

  19. Left dorso-lateral repetitive transcranial magnetic stimulation affects cortical excitability and functional connectivity, but does not impair cognition in major depression.

    Science.gov (United States)

    Shajahan, Polash M; Glabus, Mike F; Steele, J Douglas; Doris, Alan B; Anderson, Kay; Jenkins, Jenny A; Gooding, Patricia A; Ebmeier, Klaus P

    2002-06-01

    Transcranial magnetic stimulation (TMS) has been used for over a decade to investigate cortical function. More recently, it has been employed to treat conditions such as major depression. This study was designed to explore the effects of differential treatment parameters, such as stimulation frequency. In addition, the data were examined to determine whether a change in connectivity occurred following TMS. Fifteen patients with major depression were entered into a combined imaging and treatment experiment with single photon emission computed tomography (SPECT) and repetitive transcranial magnetic stimulation (rTMS) over left dorso-lateral prefrontal cortex (DLPFC). Brain perfusion during a verbal fluency task was compared between pre- and poststimulation conditions. Patients were then treated with 80% of motor threshold for a total of 10 days, using 5000 stimuli at 5, 10 or 20 Hz. Tests of cortical excitability and neuropsychological tests were done throughout the trial. Patients generally improved with treatment. There was no perceptible difference between stimulation frequencies, which may have reflected low study power. An increase in rostral anterior cingulate activation after the treatment day was associated with increased functional connectivity in the dorso-lateral frontal loop on the left and the limbic loop on both sides. No noticeable deterioration in neuropsychological function was observed. TMS at the stimulation frequencies used seems to be safe over a course of 5000 stimuli. It appears to have an activating effect in anterior limbic structures and increase functional connectivity in the neuroanatomical networks under the stimulation coil within an hour of stimulation.

  20. Comparative study of body surface isopotential map, left ventriculogram and thallium-201 myocardial scintigram in patients with old lateral myocardial infarction

    International Nuclear Information System (INIS)

    Matsumoto, Naoyuki

    1988-01-01

    In 16 patients with old lateral myocardial infarction, body surface isopotential maps and 12 lead electrocardiograms were compared with left ventriculographic findings. In addition 8 of these subjects were performed thallium-201 myocardial scintigraphy in order to determine the location and extent of myocardial necrosis. Common 12 lead electrocardiographic findings of the subjects were initial Q waves more than 30 msec and inverted T waves in only aVL lead. The patients were classified into 4 groups according to the location and extent of ventricular wall motion abnormalities group I (6 cases) showed hypokinesis in the anterior segment, group II (5 cases): akinesis in the anterior segment and hypokinesis in the seg. 6, group III (4 cases): hypokinesis in the anterior segment and seg. 7, group IV (1 case): hypokinesis in the anterior segment and seg. 4, 7. And each of the 4 groups demonstrated characteristic findings of surface isopotential maps. Group II with coexisting hypokinesis in the seg. 6 showed surface isopotential maps additional pattern of anterior myocardial infarction, and group III with coexisting hypokinesis in the seg. 7 showed additional patterns of posterior myocardial infarction. The classification according to the abnormality of ventricular wall motion was also conformed with the thallium-201 myocardial scintigraphic findings except one case. These results suggest that body surface isopotential map is more useful than the 12 lead electrocardiogram in detecting the location and extent of left ventricular wall motion abnormality in patients with old lateral myocardial infarction. (author) 53 refs

  1. Anterior temporal lobe white matter abnormal signal (ATLAS) as an indicator of seizure focus laterality in temporal lobe epilepsy: comparison of double inversion recovery, FLAIR and T2W MR imaging

    Energy Technology Data Exchange (ETDEWEB)

    Morimoto, Emiko; Kanagaki, Mitsunori; Okada, Tomohisa; Yamamoto, Akira; Togashi, Kaori [Kyoto University Graduate School of Medicine, Department of Diagnostic Imaging and Nuclear Medicine, Kyoto (Japan); Mori, Nobuyuki [Tenri Hospital, Department of Radiology, Tenri, Nara (Japan); Matsumoto, Riki; Ikeda, Akio; Takahashi, Ryosuke [Kyoto University Graduate School of Medicine, Department of Neurology, Kyoto (Japan); Mikuni, Nobuhiro [Sapporo Medical University, Department of Neurosurgery, Sapporo, Hokkaido (Japan); Kunieda, Takeharu; Miyamoto, Susumu [Kyoto University Graduate School of Medicine, Department of Neurosurgery, Kyoto (Japan); Paul, Dominik [Siemens AG Healthcare Sector, Erlangen (Germany)

    2013-01-15

    To investigate the diagnostic capability of anterior temporal lobe white matter abnormal signal (ATLAS) for determining seizure focus laterality in temporal lobe epilepsy (TLE) by comparing different MR sequences. This prospective study was approved by the institutional review board and written informed consent was obtained. Three 3D sequences (double inversion recovery (DIR), fluid-attenuated inversion recovery (FLAIR) and T2-weighted imaging (T2WI)) and two 2D sequences (FLAIR and T2WI) were acquired at 3 T. Signal changes in the anterior temporal white matter of 21 normal volunteers were evaluated. ATLAS laterality was evaluated in 21 TLE patients. Agreement of independent evaluations by two neuroradiologists was assessed using {kappa} statistics. Differences in concordance between ATLAS laterality and clinically defined seizure focus laterality were analysed using McNemar's test with multiple comparisons. Pre-amygdala high signals (PAHS) were detected in all volunteers only on 3D-DIR. Inter-evaluator agreement was moderate to almost perfect for each sequence. Correct diagnosis of seizure laterality was significantly more frequent on 3D-DIR than on any other sequences (P {<=} 0.031 for each evaluator). The most sensitive sequence for detecting ATLAS laterality was 3D-DIR. ATLAS laterality on 3D-DIR can be a good indicator for determining seizure focus localization in TLE. (orig.)

  2. Anterior temporal lobe white matter abnormal signal (ATLAS) as an indicator of seizure focus laterality in temporal lobe epilepsy: comparison of double inversion recovery, FLAIR and T2W MR imaging

    International Nuclear Information System (INIS)

    Morimoto, Emiko; Kanagaki, Mitsunori; Okada, Tomohisa; Yamamoto, Akira; Togashi, Kaori; Mori, Nobuyuki; Matsumoto, Riki; Ikeda, Akio; Takahashi, Ryosuke; Mikuni, Nobuhiro; Kunieda, Takeharu; Miyamoto, Susumu; Paul, Dominik

    2013-01-01

    To investigate the diagnostic capability of anterior temporal lobe white matter abnormal signal (ATLAS) for determining seizure focus laterality in temporal lobe epilepsy (TLE) by comparing different MR sequences. This prospective study was approved by the institutional review board and written informed consent was obtained. Three 3D sequences (double inversion recovery (DIR), fluid-attenuated inversion recovery (FLAIR) and T2-weighted imaging (T2WI)) and two 2D sequences (FLAIR and T2WI) were acquired at 3 T. Signal changes in the anterior temporal white matter of 21 normal volunteers were evaluated. ATLAS laterality was evaluated in 21 TLE patients. Agreement of independent evaluations by two neuroradiologists was assessed using κ statistics. Differences in concordance between ATLAS laterality and clinically defined seizure focus laterality were analysed using McNemar's test with multiple comparisons. Pre-amygdala high signals (PAHS) were detected in all volunteers only on 3D-DIR. Inter-evaluator agreement was moderate to almost perfect for each sequence. Correct diagnosis of seizure laterality was significantly more frequent on 3D-DIR than on any other sequences (P ≤ 0.031 for each evaluator). The most sensitive sequence for detecting ATLAS laterality was 3D-DIR. ATLAS laterality on 3D-DIR can be a good indicator for determining seizure focus localization in TLE. (orig.)

  3. Peri-ictal water drinking and other ictal vegetative symptoms: Localizing and lateralizing the epileptogenic zone in temporal lobe epilepsy? Two case reports and review of the literature.

    Science.gov (United States)

    Errguig, L; Lahjouji, F; Belaidi, H; Jiddane, M; Elkhamlichi, A; Dakka, T; Ouazzani, R

    2013-11-01

    Peri-ictal behavior disorders can be helpful in localizing and lateralizing seizure onset in partial epilepsies, especially those originating in the temporal lobe. In this paper, we present the case of two right-handed women aged 36 and 42 years who presented with partial seizures of mesial temporal type. Both of the patients had drug resistant epilepsy and undergone presurgical evaluation tests including brain magnetic resonance imaging, video-EEG monitoring and neuropsychological testing. The two patients had hippocampal sclerosis in the right temporal lobe and exhibited PIWD behavior concomitant with right temporal lobe discharges documented during video-EEG recordings. Anterior temporal lobectomy was performed in one case with an excellent outcome after surgery. The patient was free of seizures at 3 years follow-up. We reviewed other publications of peri-ictal autonomic symptoms considered to have a lateralizing significance, such as peri-ictal vomiting, urinary urge, ictal pilo-erection. Clinicians should search for these symptoms, even if not spontaneously reported by the patient, because they are often under-estimated, both by the patients themselves and by physicians. Additionally, patients with lateralizing auras during seizures have a significantly better outcome after epilepsy surgery than those without lateralizing features. Copyright © 2013. Published by Elsevier Masson SAS.

  4. Multiple sclerosis: Left advantage for auditory laterality in dichotic tests of central auditory processing and relationship of psychoacoustic tests with the Multiple Sclerosis Disability Scale-EDSS.

    Science.gov (United States)

    Peñaloza López, Yolanda Rebeca; Orozco Peña, Xóchitl Daisy; Pérez Ruiz, Santiago Jesús

    2018-04-03

    To evaluate the central auditory processing disorders in patients with multiple sclerosis, emphasizing auditory laterality by applying psychoacoustic tests and to identify their relationship with the Multiple Sclerosis Disability Scale (EDSS) functions. Depression scales (HADS), EDSS, and 9 psychoacoustic tests to study CAPD were applied to 26 individuals with multiple sclerosis and 26 controls. Correlation tests were performed between the EDSS and psychoacoustic tests. Seven out of 9 psychoacoustic tests were significantly different (P<.05); right or left (14/19 explorations) with respect to control. In dichotic digits there was a left-ear advantage compared to the usual predominance of RDD. There was significant correlation in five psychoacoustic tests and the specific functions of EDSS. The left-ear advantage detected and interpreted as an expression of deficient influences of the corpus callosum and attention in multiple sclerosis should be investigated. There was a correlation between psychoacoustic tests and specific EDSS functions. Copyright © 2018 Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. Seeking homeostasis: Temporal trends in respiration, oxidation, and calcium in SOD1 G93A Amyotrophic Lateral Sclerosis mice

    Directory of Open Access Journals (Sweden)

    Cameron W Irvin

    2015-07-01

    Full Text Available Impairments in mitochondria, oxidative regulation, and calcium homeostasis have been well documented in numerous amyotrophic lateral sclerosis (ALS experimental models, especially in the superoxide dismutase 1 glycine 93 to alanine (SOD1 G93A transgenic mouse. However, the timing of these deficiencies has been debatable. In a systematic review of 45 articles, we examine experimental measurements of cellular respiration, mitochondrial mechanisms, oxidative markers, and calcium regulation. We evaluate the quantitative magnitude and statistical temporal trend of these aggregated assessments in high transgene copy SOD1 G93A mice compared to wild type mice. Analysis of overall trends reveals cellular respiration, intracellular ATP, and corresponding mitochondrial elements (Cox, cytochrome c, complex I, enzyme activity are depressed for the entire lifespan of the SOD1 G93A mouse. Oxidant markers (H2O2, 8OH2’dG, MDA are initially similar to wild type but are double that of wild type by the time of symptom onset despite early post-natal elevation of protective heat shock proteins. All aspects of calcium regulation show early disturbances, although a notable and likely compensatory convergence to near wild type levels appears to occur between 40-80 days (pre-onset, followed by a post-onset elevation in intracellular calcium. The identified temporal trends and compensatory fluctuations provide evidence that the cause of ALS may lay within failed homeostatic regulation, itself, rather than any one particular perturbing event or cellular mechanism. We discuss the vulnerabilities of motoneurons to regulatory instability and possible hypotheses regarding failed regulation and its potential treatment in ALS.

  6. Temporal auditory processing at 17 months of age is associated with preliterate language comprehension and later word reading fluency : An ERP study

    NARCIS (Netherlands)

    van Zuijen, Titia L.; Plakas, Anna; Maassen, Ben A. M.; Been, Pieter; Maurits, Natasha M.; Krikhaar, Evelien; van Driel, Joram; van der Leij, Aryan

    2012-01-01

    Dyslexia is heritable and associated with auditory processing deficits. We investigate whether temporal auditory processing is compromised in young children at-risk for dyslexia and whether it is associated with later language and reading skills. We recorded EEG from 17 months-old children with or

  7. Temporal auditory processing at 17 months of age is associated with preliterate language comprehension and later word reading fluency: An ERP study

    NARCIS (Netherlands)

    Van Zuijen, Titia L.; Plakas, Anna; Maassen, Ben A M; Been, Pieter; Maurits, Natasha M.; Krikhaar, Evelien; van Driel, Joram; van der Leij, Aryan

    2012-01-01

    Dyslexia is heritable and associated with auditory processing deficits. We investigate whether temporal auditory processing is compromised in young children at-risk for dyslexia and whether it is associated with later language and reading skills. We recorded EEG from 17 months-old children with or

  8. Evidence for Mojave-Sonora megashear-Systematic left-lateral offset of Neoproterozoic to Lower Jurassic strata and facies, western United States and northwestern Mexico

    Science.gov (United States)

    Stewart, John H.

    2005-01-01

    Major successions as well as individual units of Neoproterozoic to Lower Jurassic strata and facies appear to be systematically offset left laterally from eastern California and western Nevada in the western United States to Sonora, Mexico. This pattern is most evident in units such as the "Johnnie oolite," a 1- to 2-m-thick oolite of the Neoproterozoic Rainstorm Member of the Johnnie Formation in the western United States and of the Clemente Formation in Sonora. The pattern is also evident in the Lower Cambrian Zabriskie Quartzite of the western United States and the correlative Proveedora Quartzite in Sonora. Matching of isopach lines of the Zabriskie Quartzite and Proveedora Quartzite suggests ???700-800 km of left-lateral offset. The offset pattern is also apparent in the distribution of distinctive lithologic types, unconformities, and fossil assemblages in other rocks ranging in age from Neoproterozoic to Early Jurassic. In the western United States, the distribution of facies in Neoproterozoic and Paleozoic strata indicates that the Cordilleran miogeocline trends north-south. A north-south trend is also suggested in Sonora, and if so is compatible with offset of the miogeocline but not with the ideas that the miogeocline wrapped around the continental margin and trends east-west in Sonora. An imperfect stratigraphic match of supposed offset segments along the megashear is apparent. Some units, such as the "Johnnie oolite" and Zabriskie-Proveedora, show almost perfect correspondence, but other units are significantly different. The differences seem to indicate that the indigenous succession of the western United States and offset segments in Mexico were not precisely side by side before offset but were separated by an area-now buried, eroded, or destroyed-that contained strata of intermediate facies. ?? 2005 Geological Society of America.

  9. Activation and Functional Connectivity of the Left Inferior Temporal Gyrus during Visual Speech Priming in Healthy Listeners and Listeners with Schizophrenia.

    Science.gov (United States)

    Wu, Chao; Zheng, Yingjun; Li, Juanhua; Zhang, Bei; Li, Ruikeng; Wu, Haibo; She, Shenglin; Liu, Sha; Peng, Hongjun; Ning, Yuping; Li, Liang

    2017-01-01

    Under a "cocktail-party" listening condition with multiple-people talking, compared to healthy people, people with schizophrenia benefit less from the use of visual-speech (lipreading) priming (VSP) cues to improve speech recognition. The neural mechanisms underlying the unmasking effect of VSP remain unknown. This study investigated the brain substrates underlying the unmasking effect of VSP in healthy listeners and the schizophrenia-induced changes in the brain substrates. Using functional magnetic resonance imaging, brain activation and functional connectivity for the contrasts of the VSP listening condition vs. the visual non-speech priming (VNSP) condition were examined in 16 healthy listeners (27.4 ± 8.6 years old, 9 females and 7 males) and 22 listeners with schizophrenia (29.0 ± 8.1 years old, 8 females and 14 males). The results showed that in healthy listeners, but not listeners with schizophrenia, the VSP-induced activation (against the VNSP condition) of the left posterior inferior temporal gyrus (pITG) was significantly correlated with the VSP-induced improvement in target-speech recognition against speech masking. Compared to healthy listeners, listeners with schizophrenia showed significantly lower VSP-induced activation of the left pITG and reduced functional connectivity of the left pITG with the bilateral Rolandic operculum, bilateral STG, and left insular. Thus, the left pITG and its functional connectivity may be the brain substrates related to the unmasking effect of VSP, assumedly through enhancing both the processing of target visual-speech signals and the inhibition of masking-speech signals. In people with schizophrenia, the reduced unmasking effect of VSP on speech recognition may be associated with a schizophrenia-related reduction of VSP-induced activation and functional connectivity of the left pITG.

  10. Temporal trend of amyotrophic lateral sclerosis incidence in southern Europe: a population study in the health district of Ferrara, Italy.

    Science.gov (United States)

    Govoni, Vittorio; Cesnik, Edward; Casetta, Ilaria; Tugnoli, Valeria; Tola, Maria Rosaria; Granieri, Enrico

    2012-08-01

    Data about the temporal trend of amyotrophic lateral sclerosis (ALS) incidence in southern Europe are scarce. Incidence studies on ALS have been carried out in the health district of Ferrara, Italy, since 1960s. We expanded the previous studies from 1964 to 2009. The study was prospective with a subsequent retrospective intensive survey of multiple sources of case ascertainment. All patients with a definite and probable ALS according to the original El Escorial criteria were selected. There were 130 incident cases in the years 1964-2009 giving an average annual crude incidence of 1.82 per 100,000 population (95% CI 1.53-2.17). An incidence increase during the study period was estimated in women (χ(2) test for trend = 7.19, p < 0.01) and in the elderly (χ(2) test for trend = 7.803, p < 0.01). The age-adjusted incidence was stable over time in both women (1.19 per 100,000, 95% CI 0.90-1.52) and men (1.45 per 100,000, 95% CI 0.12-1.84). The annual number of new ALS cases in the study population followed the Poisson distribution in both sexes as well as in the elderly group of the population. The present findings suggest that ALS incidence is nearly stable over time. The crude incidence increase we estimated over time among women is mainly explained by population ageing. The increasing incidence in the elderly population was likely the consequence of an increasing precision in ALS diagnosis in the elderly since the increasing attention and care over time of neurologic elderly patients that likely concern elderly women more than previous time periods rather than better case ascertainment of diagnosed patients. The present findings do not support the role of specific environmental factors in ALS pathogenesis.

  11. Speech-induced striatal dopamine release is left lateralized and coupled to functional striatal circuits in healthy humans: A combined PET, fMRI and DTI study

    Science.gov (United States)

    Simonyan, Kristina; Herscovitch, Peter; Horwitz, Barry

    2013-01-01

    Considerable progress has been recently made in understanding the brain mechanisms underlying speech and language control. However, the neurochemical underpinnings of normal speech production remain largely unknown. We investigated the extent of striatal endogenous dopamine release and its influences on the organization of functional striatal speech networks during production of meaningful English sentences using a combination of positron emission tomography (PET) with the dopamine D2/D3 receptor radioligand [11C]raclopride and functional MRI (fMRI). In addition, we used diffusion tensor tractography (DTI) to examine the extent of dopaminergic modulatory influences on striatal structural network organization. We found that, during sentence production, endogenous dopamine was released in the ventromedial portion of the dorsal striatum, in its both associative and sensorimotor functional divisions. In the associative striatum, speech-induced dopamine release established a significant relationship with neural activity and influenced the left-hemispheric lateralization of striatal functional networks. In contrast, there were no significant effects of endogenous dopamine release on the lateralization of striatal structural networks. Our data provide the first evidence for endogenous dopamine release in the dorsal striatum during normal speaking and point to the possible mechanisms behind the modulatory influences of dopamine on the organization of functional brain circuits controlling normal human speech. PMID:23277111

  12. Timing of metamorphism of the Lansang gneiss and implications for left-lateral motion along the Mae Ping (Wang Chao) strike-slip fault, Thailand

    Science.gov (United States)

    Palin, R. M.; Searle, M. P.; Morley, C. K.; Charusiri, P.; Horstwood, M. S. A.; Roberts, N. M. W.

    2013-10-01

    The Mae Ping fault (MPF), western Thailand, exhibits dominantly left-lateral strike-slip motion and stretches for >600 km, reportedly branching off the right-lateral Sagaing fault in Myanmar and extending southeast towards Cambodia. Previous studies have suggested that the fault assisted the large-scale extrusion of Sundaland that occurred during the Late Eocene-Early Oligocene, with a geological offset of ˜120-150 km estimated from displaced high-grade gneisses and granites of the Chiang Mai-Lincang belt. Exposures of high-grade orthogneiss in the Lansang National Park, part of this belt, locally contain strong mylonitic textures and are bounded by strike-slip ductile shear zones and brittle faults. Geochronological analysis of monazite from a sample of sheared biotite-K-feldspar orthogneiss suggests two episodes of crystallization, with core regions documenting Th-Pb ages between c. 123 and c. 114 Ma and rim regions documenting a significantly younger age range between c. 45-37 Ma. These data are interpreted to represent possible magmatic protolith emplacement for the Lansang orthogneiss during the Early Cretaceous, with a later episode of metamorphism occurring during the Eocene. Textural relationships provided by in situ analysis suggest that ductile shearing along the MPF occurred during the latter stages of, or after, this metamorphic event. In addition, monazite analyzed from an undeformed garnet-two-mica granite dyke intruding metamorphic units at Bhumipol Lake outside of the Mae Ping shear zone produced a Th-Pb age of 66.2 ± 1.6 Ma. This age is interpreted to date the timing of dyke emplacement, implying that the MPF cuts through earlier formed magmatic and high-grade metamorphic rocks. These new data, when combined with regional mapping and earlier geochronological work, show that neither metamorphism, nor regional cooling, was directly related to strike-slip motion.

  13. Crossed cerebellar hyperperfusion on ictal Tc-99m HMPAO brain SPECT: clinical significance for differentiation of mesial or lateral temporal lobe epilepsy and related factors for development

    International Nuclear Information System (INIS)

    Park, Soon Ah; Sohn, Myung Hee; Lim, Seok Tae; Lee, Dong Soo; Lee, Sang Gun; Kim, Seok Ki; Jang, Myoung Jin; Chung, June Key; Lee, Myung Chul

    2000-01-01

    The aim of this study was to determine whether crossed cerebellar hyperperfusion (CCH) was helpful in discriminating mesial from lateral temporal lobe epilepsy (TLE) and what other factors were related in the development of CCH on ictal brain SPECT. We conducted retrospective analysis in 59 patients with TLE (M:41, F:18; 27.4±7.8 years old; mesial TLE: 51, lateral TLE: 8), which was confirmed by invasive EEG and surgical outcome (Engel class 1, 2). All the patients underwent ictal Tc-99m HMPAO brain SPECT and their injection time from ictal EEG onset on video EEG monitoring ranged from 11 sec to 75 sec (32.6±19.5 sec) in 39 patients. Multiple factors including age, TLE subtype (mesial TLE or lateral TLE), propatation pattern (hyperperfusion localized to temporal lobes, spread to adjacent lobes or contralateral hemisphere) and injection time were evaluated for their relationship with CCH using multiple logistic regression analysis CCH was observed in 18 among 59 patients. CCH developed in 29% (15/51) of mesial TLE patients and 38% (3/8) of lateral TLE patients. CCH was associated with propagation pattern; no CCH (0/13) in patients with hyperperfusion localized to temporal lobe, 30% (7/23) in patients with propagation to adjacent lobes, 48% (11/23) to contralateral hemisphere. Multiple logistic regression analysis revealed that propagation pattern (p=3D0.01) and age (p=3D0.02) were related to the development of CCH. Crossed cerebellar hyperperfusion in ictal brain SPECT did not help differentiate mesial from lateral remporal lobe epilepsy. Crossed cerebellar hyperperfusion was associated with propagation pattern of temporal lobe epilepsy and age.=20

  14. Crossed cerebellar hyperperfusion on ictal Tc-99m HMPAO brain SPECT: clinical significance for differentiation of mesial or lateral temporal lobe epilepsy and related factors for development

    Energy Technology Data Exchange (ETDEWEB)

    Park, Soon Ah; Sohn, Myung Hee; Lim, Seok Tae [Chonbuk National Univ. School of Medicine, Chonju (Korea, Republic of); Lee, Dong Soo; Lee, Sang Gun; Kim, Seok Ki; Jang, Myoung Jin; Chung, June Key; Lee, Myung Chul [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2000-08-01

    The aim of this study was to determine whether crossed cerebellar hyperperfusion (CCH) was helpful in discriminating mesial from lateral temporal lobe epilepsy (TLE) and what other factors were related in the development of CCH on ictal brain SPECT. We conducted retrospective analysis in 59 patients with TLE (M:41, F:18; 27.4{+-}7.8 years old; mesial TLE: 51, lateral TLE: 8), which was confirmed by invasive EEG and surgical outcome (Engel class 1, 2). All the patients underwent ictal Tc-99m HMPAO brain SPECT and their injection time from ictal EEG onset on video EEG monitoring ranged from 11 sec to 75 sec (32.6{+-}19.5 sec) in 39 patients. Multiple factors including age, TLE subtype (mesial TLE or lateral TLE), propatation pattern (hyperperfusion localized to temporal lobes, spread to adjacent lobes or contralateral hemisphere) and injection time were evaluated for their relationship with CCH using multiple logistic regression analysis CCH was observed in 18 among 59 patients. CCH developed in 29% (15/51) of mesial TLE patients and 38% (3/8) of lateral TLE patients. CCH was associated with propagation pattern; no CCH (0/13) in patients with hyperperfusion localized to temporal lobe, 30% (7/23) in patients with propagation to adjacent lobes, 48% (11/23) to contralateral hemisphere. Multiple logistic regression analysis revealed that propagation pattern (p=3D0.01) and age (p=3D0.02) were related to the development of CCH. Crossed cerebellar hyperperfusion in ictal brain SPECT did not help differentiate mesial from lateral remporal lobe epilepsy. Crossed cerebellar hyperperfusion was associated with propagation pattern of temporal lobe epilepsy and age.

  15. Top-down and bottom-up influences on the left ventral occipito-temporal cortex during visual word recognition: an analysis of effective connectivity.

    Science.gov (United States)

    Schurz, Matthias; Kronbichler, Martin; Crone, Julia; Richlan, Fabio; Klackl, Johannes; Wimmer, Heinz

    2014-04-01

    The functional role of the left ventral occipito-temporal cortex (vOT) in visual word processing has been studied extensively. A prominent observation is higher activation for unfamiliar but pronounceable letter strings compared to regular words in this region. Some functional accounts have interpreted this finding as driven by top-down influences (e.g., Dehaene and Cohen [2011]: Trends Cogn Sci 15:254-262; Price and Devlin [2011]: Trends Cogn Sci 15:246-253), while others have suggested a difference in bottom-up processing (e.g., Glezer et al. [2009]: Neuron 62:199-204; Kronbichler et al. [2007]: J Cogn Neurosci 19:1584-1594). We used dynamic causal modeling for fMRI data to test bottom-up and top-down influences on the left vOT during visual processing of regular words and unfamiliar letter strings. Regular words (e.g., taxi) and unfamiliar letter strings of pseudohomophones (e.g., taksi) were presented in the context of a phonological lexical decision task (i.e., "Does the item sound like a word?"). We found no differences in top-down signaling, but a strong increase in bottom-up signaling from the occipital cortex to the left vOT for pseudohomophones compared to words. This finding can be linked to functional accounts which assume that the left vOT contains neurons tuned to complex orthographic features such as morphemes or words [e.g., Dehaene and Cohen [2011]: Trends Cogn Sci 15:254-262; Kronbichler et al. [2007]: J Cogn Neurosci 19:1584-1594]: For words, bottom-up signals converge onto a matching orthographic representation in the left vOT. For pseudohomophones, the propagated signals do not converge, but (partially) activate multiple orthographic word representations, reflected in increased effective connectivity. Copyright © 2013 Wiley Periodicals, Inc.

  16. Evaluation of focus laterality in temporal lobe epilepsy: a quantitative study comparing double inversion-recovery MR imaging at 3T with FDG-PET.

    Science.gov (United States)

    Morimoto, Emiko; Okada, Tomohisa; Kanagaki, Mitsunori; Yamamoto, Akira; Fushimi, Yasutaka; Matsumoto, Riki; Takaya, Shigetoshi; Ikeda, Akio; Kunieda, Takeharu; Kikuchi, Takayuki; Paul, Dominik; Miyamoto, Susumu; Takahashi, Ryosuke; Togashi, Kaori

    2013-12-01

    To quantitatively compare the diagnostic capability of double inversion-recovery (DIR) with F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) for detection of seizure focus laterality in temporal lobe epilepsy (TLE). This study was approved by the institutional review board, and written informed consent was obtained. Fifteen patients with TLE and 38 healthy volunteers were enrolled. All magnetic resonance (MR) images were acquired using a 3T-MRI system. Voxel-based analysis (VBA) was conducted for FDG-PET images and white matter segments of DIR images (DIR-WM) focused on the whole temporal lobe (TL) and the anterior part of the temporal lobe (ATL). Distribution of hypometabolic areas on FDG-PET and increased signal intensity areas on DIR-WM were evaluated, and their laterality was compared with clinically determined seizure focus laterality. Correct diagnostic rates of laterality were evaluated, and agreement between DIR-WM and FDG-PET was assessed using κ statistics. Increased signal intensity areas on DIR-WM were located at the vicinity of the hypometabolic areas on FDG-PET, especially in the ATL. Correct diagnostic rates of seizure focus laterality for DIR-WM (0.80 and 0.67 for the TL and the ATL, respectively) were slightly higher than those for FDG-PET (0.67 and 0.60 for the TL and the ATL, respectively). Agreement of laterality between DIR-WM and FDG-PET was substantial for the TL and almost perfect for the ATL (κ = 0.67 and 0.86, respectively). High agreement in localization between DIR-WM and FDG-PET and nearly equivalent detectability of them show us an additional role of MRI in TLE. Wiley Periodicals, Inc. © 2013 International League Against Epilepsy.

  17. Connectivity and tissue microstructural alterations in right and left temporal lobe epilepsy revealed by diffusion spectrum imaging

    Directory of Open Access Journals (Sweden)

    Alia Lemkaddem

    2014-01-01

    Global connectivity, hub architecture and regional connectivity patterns were altered in TLE patients and showed different characteristics in RTLE vs LTLE with stronger abnormalities in RTLE. The microstructural analysis suggested that disturbed axonal density contributed more than fiber orientation to the connectivity changes affecting the temporal lobes whereas fiber orientation changes were more involved in extratemporal lobe changes. Our study provides further structural evidence that RTLE and LTLE are not symmetrical entities and DSI-based imaging could help investigate the microstructural correlate of these imaging abnormalities.

  18. A comparison of prone SPET and left lateral (decubitus) planar imaging for inferior wall attenuation artefact in 201Tl myocardial imaging

    International Nuclear Information System (INIS)

    O'Donnell, M.; Jenkin, B.; Van Every, B.; Kelly, M.J.; Kalff, V.

    1999-01-01

    Full text: Inferior wall attenuation artefacts are a major problem in supine SPET (S-S) myocardial perfusion imaging. SPET imaging with the patient lying in the prone position (P-S) and left lateral planar imaging with the patient lying in the right lateral decubitus position (LL) ameliorate this artefact. This study attempts to define the clinical role of P-S and LL imaging in characterizing S-S inferior wall defects. 21 patients with an inferior wall defect on S-S then had LL and rapid P-S imaging. All images were performed with a GE Optima NX gamma camera using GENIE acquisition and processing. All SPETs used 16 stops (32 frames) through 90 deg, with 40 s per stop for SS and 14 s per stop for P-S. LL images were acquired for 150 s. All images were assessed for adequacy and inferior wall scored for 0 = no, 1 mild, 2 moderate and 3 = severe defects. Statistical analysis was performed using the Wilcoxon rank sum test for matched pairs. All images were adequate for analysis. Significantly fewer defects were seen in P-S vs S-S, LL vs S-S (P 0.88); however; there was a difference (P < 0.05) in the subgroup (n = 7) with moderate defects on S-S imaging but no LL defect. In conclusion, most inferior wall defects seen on S-S imaging can be attributed to either attenuation or true perfusion defects with the use of LL imaging. Prone imaging may only be helpful where the inferior defect is of moderate severity but no LL defect is seen

  19. Clinical utility of the Wechsler Memory Scale--Fourth Edition (WMS-IV) in predicting laterality of temporal lobe epilepsy among surgical candidates.

    Science.gov (United States)

    Soble, Jason R; Eichstaedt, Katie E; Waseem, Hena; Mattingly, Michelle L; Benbadis, Selim R; Bozorg, Ali M; Vale, Fernando L; Schoenberg, Mike R

    2014-12-01

    This study evaluated the accuracy of the Wechsler Memory Scale--Fourth Edition (WMS-IV) in identifying functional cognitive deficits associated with seizure laterality in localization-related temporal lobe epilepsy (TLE) relative to a previously established measure, the Rey Auditory Verbal Learning Test (RAVLT). Emerging WMS-IV studies have highlighted psychometric improvements that may enhance its ability to identify lateralized memory deficits. Data from 57 patients with video-EEG-confirmed unilateral TLE who were administered the WMS-IV and RAVLT as part of a comprehensive presurgical neuropsychological evaluation for temporal resection were retrospectively reviewed. We examined the predictive accuracy of the WMS-IV not only in terms of verbal versus visual composite scores but also using individual subtests. A series of hierarchal logistic regression models were developed, including the RAVLT, WMS-IV delayed subtests (Logical Memory, Verbal Paired Associates, Designs, Visual Reproduction), and a WMS-IV verbal-visual memory difference score. Analyses showed that the RAVLT significantly predicted laterality with overall classification rates of 69.6% to 70.2%, whereas neither the individual WMS-IV subtests nor the verbal-visual memory difference score accounted for additional significant variance. Similar to previous versions of the WMS, findings cast doubt as to whether the WMS-IV offers significant incremental validity in discriminating seizure laterality in TLE beyond what can be obtained from the RAVLT. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Reduced parahippocampal and lateral temporal GABA{sub A}-[{sup 11}C]flumazenil binding in major depression: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Klumpers, Ursula M.H. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); GGZ inGeest, partner of VUmc, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Veltman, Dick J. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Drent, Madeleine L. [VU University Medical Center, Department of Endocrinology, Amsterdam (Netherlands); Boellaard, Ronald; Lammertsma, Adriaan A. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands); Comans, Emile F.I. [VU University Medical Center, Department of Nuclear Medicine and PET Research, Amsterdam (Netherlands); Meynen, Gerben [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); Hoogendijk, Witte J.G. [VU University Medical Center, Department of Psychiatry, Amsterdam (Netherlands); VU University Medical Center, Center for Neurogenomics and Cognitive Research, Amsterdam (Netherlands); VU University Medical Center, Neuroscience Campus Amsterdam, Amsterdam (Netherlands)

    2010-03-15

    Major depressive disorder (MDD) has been related to both a dysfunctional {gamma}-amino butyric acid (GABA) system and to hyperactivity of the hypothalamic-pituitary-adrenal axis (HPA). Although GABA has been suggested to inhibit HPA axis activity, their relationship has never been studied at the level of the central GABA{sub A}-benzodiazepine receptor in depressed patients or in relation to antidepressant treatment. Eleven depressed outpatients were compared, before and after treatment with citalopram, with nine age-matched healthy controls. The subjects were scanned using the positron emission tomography (PET) tracer [{sup 11}C]flumazenil ([{sup 11}C]FMZ). Parametric voxel-by-voxel Logan plots were compared with methods based on regions of interest (ROI), to provide volume of distribution (V{sub T}) and binding potential (BP{sub ND}) values. Plasma GABA levels were determined and a dexamethasone-corticotropin releasing hormone (DEX-CRH) test was performed. In MDD, parametric voxel-by-voxel Logan plots showed bilateral reduced [{sup 11}C]FMZ binding in the parahippocampal gyrus and right lateral superior temporal gyrus (p uncorrected {<=}0.001). In the temporal area, [{sup 11}C]FMZ binding showed a strong inverse correlation with HPA axis activity. Plasma GABA did not discriminate MDD from controls, but correlated inversely with [{sup 11}C]FMZ binding in the right insula. Following treatment with citalopram, voxel-based analysis revealed reduced binding in the right lateral temporal gyrus and dorsolateral prefrontal cortex. The bilateral reduction in limbic parahippocampal and right temporal [{sup 11}C]FMZ binding found in MDD indicates decreased GABA{sub A}-benzodiazepine receptor complex affinity and/or number. The inverse relationship between GABA{sub A} binding in the temporal lobe and HPA axis activity, suggests that HPA axis hyperactivity is partly due to reduced GABA-ergic inhibition. (orig.)

  1. Using of Remote Sensing Techniques for Monitoring the Earthquakes Activities Along the Northern Part of the Syrian Rift System (LEFT-LATERAL),SYRIA

    Science.gov (United States)

    Dalati, Moutaz

    Earthquake mitigation can be achieved with a better knowledge of a region's infra-and substructures. High resolution Remote Sensing data can play a significant role to implement Geological mapping and it is essential to learn about the tectonic setting of a region. It is an effective method to identify active faults from different sources of Remote Sensing and compare the capability of some satellite sensors in active faults survey. In this paper, it was discussed a few digital image processing approaches to be used for enhancement and feature extraction related to faults. Those methods include band ratio, filtering and texture statistics . The experimental results show that multi-spectral images have great potentials in large scale active faults investigation. It has also got satisfied results when deal with invisible faults. Active Faults have distinct features in satellite images. Usually, there are obvious straight lines, circular structures and other distinct patterns along the faults locations. Remotely Sensed imagery Landsat ETM and SPOT XS /PAN are often used in active faults mapping. Moderate and high resolution satellite images are the best choice, because in low resolution images, the faults features may not be visible in most cases. The area under study is located Northwest of Syria that is part of one of the very active deformation belt on the Earth today. This area and the western part of Syria are located along the great rift system (Left-Lateral or African- Syrian Rift System). Those areas are tectonically active and caused a lot of seismically events. The AL-Ghab graben complex is situated within this wide area of Cenozoic deformation. The system formed, initially, as a result of the break up of the Arabian plate from the African plate. This action indicates that these sites are active and in a continual movement. In addition to that, the statistic analysis of Thematic Mapper data and the features from a digital elevation model ( DEM )produced from

  2. Connectivity and tissue microstructural alterations in right and left temporal lobe epilepsy revealed by diffusion spectrum imaging.

    Science.gov (United States)

    Lemkaddem, Alia; Daducci, Alessandro; Kunz, Nicolas; Lazeyras, François; Seeck, Margitta; Thiran, Jean-Philippe; Vulliémoz, Serge

    2014-01-01

    Focal epilepsy is increasingly recognized as the result of an altered brain network, both on the structural and functional levels and the characterization of these widespread brain alterations is crucial for our understanding of the clinical manifestation of seizure and cognitive deficits as well as for the management of candidates to epilepsy surgery. Tractography based on Diffusion Tensor Imaging allows non-invasive mapping of white matter tracts in vivo. Recently, diffusion spectrum imaging (DSI), based on an increased number of diffusion directions and intensities, has improved the sensitivity of tractography, notably with respect to the problem of fiber crossing and recent developments allow acquisition times compatible with clinical application. We used DSI and parcellation of the gray matter in regions of interest to build whole-brain connectivity matrices describing the mutual connections between cortical and subcortical regions in patients with focal epilepsy and healthy controls. In addition, the high angular and radial resolution of DSI allowed us to evaluate also some of the biophysical compartment models, to better understand the cause of the changes in diffusion anisotropy. Global connectivity, hub architecture and regional connectivity patterns were altered in TLE patients and showed different characteristics in RTLE vs LTLE with stronger abnormalities in RTLE. The microstructural analysis suggested that disturbed axonal density contributed more than fiber orientation to the connectivity changes affecting the temporal lobes whereas fiber orientation changes were more involved in extratemporal lobe changes. Our study provides further structural evidence that RTLE and LTLE are not symmetrical entities and DSI-based imaging could help investigate the microstructural correlate of these imaging abnormalities.

  3. Lateralization of temporal lobe epilepsy using a novel uncertainty analysis of MR diffusion in hippocampus, cingulum, and fornix, and hippocampal volume and FLAIR intensity.

    Science.gov (United States)

    Nazem-Zadeh, Mohammad-Reza; Schwalb, Jason M; Elisevich, Kost V; Bagher-Ebadian, Hassan; Hamidian, Hajar; Akhondi-Asl, Ali-Reza; Jafari-Khouzani, Kourosh; Soltanian-Zadeh, Hamid

    2014-07-15

    To analyze the utility of a quantitative uncertainty analysis approach for evaluation and comparison of various MRI findings for the lateralization of epileptogenicity in mesial temporal lobe epilepsy (mTLE), including novel diffusion-based analyses. We estimated the hemispheric variation uncertainty (HVU) of hippocampal T1 volumetry and FLAIR (Fluid Attenuated Inversion Recovery) intensity. Using diffusion tensor images of 23 nonepileptic subjects, we estimated the HVU levels of mean diffusivity (MD) in the hippocampus, and fractional anisotropy (FA) in the posteroinferior cingulum and crus of fornix. Imaging from a retrospective cohort of 20 TLE patients who had undergone surgical resection with Engel class I outcomes was analyzed to determine whether asymmetry of preoperative volumetrics, FLAIR intensities, and MD values in hippocampi, as well as FA values in posteroinferior cingula and fornix crura correctly predicted laterality of seizure onset. Ten of the cohort had pathologically proven mesial temporal sclerosis (MTS). Seven of these patients had undergone extraoperative electrocorticography (ECoG) for lateralization or to rule out extra-temporal foci. HVU was estimated to be 3.1×10(-5) for hippocampal MD, 0.027 for FA in posteroinferior cingulum, 0.018 for FA in crus of fornix, 0.069 for hippocampal normalized volume, and 0.099 for hippocampal normalized FLAIR intensity. Using HVU analysis, a higher hippocampal MD value, lower FA within the posteroinferior cingulum and crus of fornix, shrinkage in hippocampal volume, and higher hippocampal FLAIR intensity were observed beyond uncertainty on the side ipsilateral to seizure onset for 10, 10, 9, 9, and 10 out of 10 pathology-proven MTS patients, respectively. Considering all 20 TLE patients, these numbers were 18, 15, 14, 13, and 16, respectively. However, consolidating the lateralization results of HVU analysis on these quantities by majority voting has detected the epileptogenic side for 19 out of 20 cases

  4. Lateralization of the human mirror neuron system.

    Science.gov (United States)

    Aziz-Zadeh, Lisa; Koski, Lisa; Zaidel, Eran; Mazziotta, John; Iacoboni, Marco

    2006-03-15

    A cortical network consisting of the inferior frontal, rostral inferior parietal, and posterior superior temporal cortices has been implicated in representing actions in the primate brain and is critical to imitation in humans. This neural circuitry may be an evolutionary precursor of neural systems associated with language. However, language is predominantly lateralized to the left hemisphere, whereas the degree of lateralization of the imitation circuitry in humans is unclear. We conducted a functional magnetic resonance imaging study of imitation of finger movements with lateralized stimuli and responses. During imitation, activity in the inferior frontal and rostral inferior parietal cortex, although fairly bilateral, was stronger in the hemisphere ipsilateral to the visual stimulus and response hand. This ipsilateral pattern is at variance with the typical contralateral activity of primary visual and motor areas. Reliably increased signal in the right superior temporal sulcus (STS) was observed for both left-sided and right-sided imitation tasks, although subthreshold activity was also observed in the left STS. Overall, the data indicate that visual and motor components of the human mirror system are not left-lateralized. The left hemisphere superiority for language, then, must be have been favored by other types of language precursors, perhaps auditory or multimodal action representations.

  5. Verbal memory after temporal lobe epilepsy surgery in children: Do only mesial structures matter?

    Science.gov (United States)

    Law, Nicole; Benifla, Mony; Rutka, James; Smith, Mary Lou

    2017-02-01

    Previous findings have been mixed regarding verbal memory outcome after left temporal lobectomy in children, and there are few studies comparing verbal memory change after lateral versus mesial temporal lobe resections. We compared verbal memory outcome associated with sparing or including the mesial structures in children who underwent left or right temporal lobe resection. We also investigated predictors of postsurgical verbal memory change. We retrospectively assessed verbal memory change approximately 1 year after unilateral temporal lobe epilepsy surgery using a list learning task. Participants included 23 children who underwent temporal lobe surgery with sparing of the mesial structures (13 left), and 40 children who had a temporal lobectomy that included resection of mesial structures (22 left). Children who underwent resection from the left lateral and mesial temporal lobe were the only group to show decline in verbal memory. Furthermore, when we considered language representation in the left temporal resection group, patients with left language representation and spared mesial structures showed essentially no change in verbal memory from preoperative to follow-up, whereas those with left language representation and excised mesial structures showed a decline. Postoperative seizure status had no effect on verbal memory change in children after left temporal lobe surgery. Finally, we found that patients with intact preoperative verbal memory experienced a significant decline compared to those with below average preoperative verbal memory. Our findings provide evidence of significant risk factors for verbal memory decline in children, specific to left mesial temporal lobe epilepsy. Children who undergo left temporal lobe surgery that includes mesial structures may be most vulnerable for verbal memory decline, especially when language representation is localized to the left hemisphere and when preoperative verbal memory is intact. Wiley Periodicals, Inc.

  6. The processing of semantic relatedness in the brain: Evidence from associative and categorical false recognition effects following transcranial direct current stimulation of the left anterior temporal lobe.

    Science.gov (United States)

    Díez, Emiliano; Gómez-Ariza, Carlos J; Díez-Álamo, Antonio M; Alonso, María A; Fernandez, Angel

    2017-08-01

    A dominant view of the role of the anterior temporal lobe (ATL) in semantic memory is that it serves as an integration hub, specialized in the processing of semantic relatedness by way of mechanisms that bind together information from different brain areas to form coherent amodal representations of concepts. Two recent experiments, using brain stimulation techniques along with the Deese-Roediger-McDermott (DRM) paradigm, have found a consistent false memory reduction effect following stimulation of the ATL, pointing to the importance of the ATL in semantic/conceptual processing. To more precisely identify the specific process being involved, we conducted a DRM experiment in which transcranial direct current stimulation (anode/cathode/sham) was applied over the participants' left ATL during the study of lists of words that were associatively related to their non-presented critical words (e.g., rotten, worm, red, tree, liqueur, unripe, cake, food, eden, peel, for the critical item apple) or categorically related (e.g., pear, banana, peach, orange, cantaloupe, watermelon, strawberry, cherry, kiwi, plum, for the same critical item apple). The results showed that correct recognition was not affected by stimulation. However, an interaction between stimulation condition and type of relation for false memories was found, explained by a significant false recognition reduction effect in the anodal condition for associative lists that was not observed for categorical lists. Results are congruent with previous findings and, more importantly, they help to clarify the nature and locus of false memory reduction effects, suggesting a differential role of the left ATL, and providing critical evidence for understanding the creation of semantic relatedness-based memory illusions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Screening LGI1 in a cohort of 26 lateral temporal lobe epilepsy patients with auditory aura from Turkey detects a novel de novo mutation.

    Science.gov (United States)

    Kesim, Yesim F; Uzun, Gunes Altiokka; Yucesan, Emrah; Tuncer, Feyza N; Ozdemir, Ozkan; Bebek, Nerses; Ozbek, Ugur; Iseri, Sibel A Ugur; Baykan, Betul

    2016-02-01

    Autosomal dominant lateral temporal lobe epilepsy (ADLTE) is an autosomal dominant epileptic syndrome characterized by focal seizures with auditory or aphasic symptoms. The same phenotype is also observed in a sporadic form of lateral temporal lobe epilepsy (LTLE), namely idiopathic partial epilepsy with auditory features (IPEAF). Heterozygous mutations in LGI1 account for up to 50% of ADLTE families and only rarely observed in IPEAF cases. In this study, we analysed a cohort of 26 individuals with LTLE diagnosed according to the following criteria: focal epilepsy with auditory aura and absence of cerebral lesions on brain MRI. All patients underwent clinical, neuroradiological and electroencephalography examinations and afterwards they were screened for mutations in LGI1 gene. The single LGI1 mutation identified in this study is a novel missense variant (NM_005097.2: c.1013T>C; p.Phe338Ser) observed de novo in a sporadic patient. This is the first study involving clinical analysis of a LTLE cohort from Turkey and genetic contribution of LGI1 to ADLTE phenotype. Identification of rare LGI1 gene mutations in sporadic cases supports diagnosis as ADTLE and draws attention to potential familial clustering of ADTLE in suggestive generations, which is especially important for genetic counselling. Copyright © 2015 Elsevier B.V. All rights reserved.

  8. Context-dependent lexical ambiguity resolution: MEG evidence for the time-course of activity in left inferior frontal gyrus and posterior middle temporal gyrus.

    Science.gov (United States)

    Mollo, Giovanna; Jefferies, Elizabeth; Cornelissen, Piers; Gennari, Silvia P

    An MEG study investigated the role of context in semantic interpretation by examining the comprehension of ambiguous words in contexts leading to different interpretations. We compared high-ambiguity words in minimally different contexts (to bowl, the bowl) to low-ambiguity counterparts (the tray, to flog). Whole brain beamforming revealed the engagement of left inferior frontal gyrus (LIFG) and posterior middle temporal gyrus (LPMTG). Points of interest analyses showed that both these sites showed a stronger response to verb-contexts by 200 ms post-stimulus and displayed overlapping ambiguity effects that were sustained from 300 ms onwards. The effect of context was stronger for high-ambiguity words than for low-ambiguity words at several different time points, including within the first 100 ms post-stimulus. Unlike LIFG, LPMTG also showed stronger responses to verb than noun contexts in low-ambiguity trials. We argue that different functional roles previously attributed to LIFG and LPMTG are in fact played out at different periods during processing. Crown Copyright © 2018. Published by Elsevier Inc. All rights reserved.

  9. TMS interferes with lexical-semantic retrieval in left inferior frontal gyrus and posterior middle temporal gyrus: Evidence from cyclical picture naming.

    Science.gov (United States)

    Krieger-Redwood, Katya; Jefferies, Elizabeth

    2014-11-01

    We used TMS to investigate the contribution of left inferior frontal gyrus (LIFG) and posterior middle temporal gyrus (pMTG) to lexical/semantic selection and retrieval processes using a cyclical naming paradigm. Participants named pictures that were presented repeatedly across six cycles, either in semantically related or unrelated sets. Previous research has suggested that selection demands are higher for related sets, especially after repetition, since participants experience competition from the activation of semantic neighbours. In contrast, retrieval demands are greater for unrelated sets in the absence of semantic priming, particularly on the first cycle when the target names have not been previously activated. Therefore, this paradigm can reveal independent effects of (i) retrieval demands (i.e., the ease of accessing picture names from visual input) and (ii) selection/competition. We found that rTMS to LIFG and pMTG produced similar behavioural effects: stimulation of both sites disrupted picture naming performance on early cycles (when participants were less practised at producing the picture names) and for semantically-related sets (when there was the potential for increased competition and yet also facilitation from semantic neighbours). There were no effects of TMS when either retrieval or selection requirements were maximal on their own. The data therefore support the view that both LIFG and pMTG contribute to picture name retrieval, with both sites playing a critical role in mediating the semantic facilitation of naming when retrieval demands are high. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. SCOPE-mTL: A non-invasive tool for identifying and lateralizing mesial temporal lobe seizures prior to scalp EEG ictal onset.

    Science.gov (United States)

    Lam, Alice D; Maus, Douglas; Zafar, Sahar F; Cole, Andrew J; Cash, Sydney S

    2017-09-01

    In mesial temporal lobe (mTL) epilepsy, seizure onset can precede the appearance of a scalp EEG ictal pattern by many seconds. The ability to identify this early, occult mTL seizure activity could improve lateralization and localization of mTL seizures on scalp EEG. Using scalp EEG spectral features and machine learning approaches on a dataset of combined scalp EEG and foramen ovale electrode recordings in patients with mTL epilepsy, we developed an algorithm, SCOPE-mTL, to detect and lateralize early, occult mTL seizure activity, prior to the appearance of a scalp EEG ictal pattern. Using SCOPE-mTL, 73% of seizures with occult mTL onset were identified as such, and no seizures that lacked an occult mTL onset were identified as having one. Predicted mTL seizure onset times were highly correlated with actual mTL seizure onset times (r=0.69). 50% of seizures with early mTL onset were lateralizable prior to scalp ictal onset, with 94% accuracy. SCOPE-mTL can identify and lateralize mTL seizures prior to scalp EEG ictal onset, with high sensitivity, specificity, and accuracy. Quantitative analysis of scalp EEG can provide important information about mTL seizures, even in the absence of a visible scalp EEG ictal correlate. Copyright © 2017 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

  11. Auras in temporal lobe epilepsy with hippocampal sclerosis: relation to seizure focus laterality and post surgical outcome.

    Science.gov (United States)

    Ferrari-Marinho, Taíssa; Caboclo, Luís Otávio S F; Marinho, Murilo M; Centeno, Ricardo S; Neves, Rafael S C; Santana, Maria Teresa C G; Brito, Fernanda S; Junior, Henrique Carrete; Yacubian, Elza Márcia T

    2012-05-01

    We examined the relationship between presence and frequency of different types of auras and side of lesion and post surgical outcomes in 205 patients with medically intractable mesial temporal lobe epilepsy (MTLE) with unilateral hippocampal sclerosis (HS). With respect to the number of auras, multiple auras were not associated with side of lesion (p=0.551). The side of HS was not associated with the type of auras reported. One hundred fifty-seven patients were operated. The occurrence of multiple auras was not associated with post-surgical outcome (p=0.740). The presence of extratemporal auras was significantly higher in patients with poor outcome. In conclusion, this study suggests that the presence of extratemporal auras in patients with MTLE-HS possibly reflects extratemporal epileptogenicity in these patients, who otherwise showed features suggestive of TLE. Therefore, TLE-HS patients undergoing pre-surgical evaluation and presenting clinical symptoms suggestive of extratemporal involvement should be more extensively evaluated to avoid incomplete resection of the epileptogenic zone. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. A functional magnetic resonance imaging study mapping the episodic memory encoding network in temporal lobe epilepsy

    Science.gov (United States)

    Sidhu, Meneka K.; Stretton, Jason; Winston, Gavin P.; Bonelli, Silvia; Centeno, Maria; Vollmar, Christian; Symms, Mark; Thompson, Pamela J.; Koepp, Matthias J.

    2013-01-01

    Functional magnetic resonance imaging has demonstrated reorganization of memory encoding networks within the temporal lobe in temporal lobe epilepsy, but little is known of the extra-temporal networks in these patients. We investigated the temporal and extra-temporal reorganization of memory encoding networks in refractory temporal lobe epilepsy and the neural correlates of successful subsequent memory formation. We studied 44 patients with unilateral temporal lobe epilepsy and hippocampal sclerosis (24 left) and 26 healthy control subjects. All participants performed a functional magnetic resonance imaging memory encoding paradigm of faces and words with subsequent out-of-scanner recognition assessments. A blocked analysis was used to investigate activations during encoding and neural correlates of subsequent memory were investigated using an event-related analysis. Event-related activations were then correlated with out-of-scanner verbal and visual memory scores. During word encoding, control subjects activated the left prefrontal cortex and left hippocampus whereas patients with left hippocampal sclerosis showed significant additional right temporal and extra-temporal activations. Control subjects displayed subsequent verbal memory effects within left parahippocampal gyrus, left orbitofrontal cortex and fusiform gyrus whereas patients with left hippocampal sclerosis activated only right posterior hippocampus, parahippocampus and fusiform gyrus. Correlational analysis showed that patients with left hippocampal sclerosis with better verbal memory additionally activated left orbitofrontal cortex, anterior cingulate cortex and left posterior hippocampus. During face encoding, control subjects showed right lateralized prefrontal cortex and bilateral hippocampal activations. Patients with right hippocampal sclerosis showed increased temporal activations within the superior temporal gyri bilaterally and no increased extra-temporal areas of activation compared with

  13. Quality of life in childhood epilepsy with lateralized epileptogenic foci

    OpenAIRE

    Mathiak Krystyna A; Łuba Małgorzata; Mathiak Klaus; Karzel Katarzyna; Wolańczyk Tomasz; Szczepanik Elżbieta; Ostaszewski Paweł

    2010-01-01

    Abstract Background Measuring quality of life (QOL) helps to delineate mechanisms underlying the interaction of disease and psychosocial factors. In adults, epileptic foci in the left temporal lobe led to lower QOL and higher depression and anxiety as compared to the right-sided foci. No study addressed the development of QOL disturbances depending on the lateralization of epileptogenic focus. The objective of our study was to examine QOL in children with lateralized epileptiform discharges. ...

  14. Language Lateralization Shifts with Learning by Adults

    Science.gov (United States)

    Plante, Elena; Almryde, Kyle; Patterson, Dianne K.; Vance, Christopher J.; Asbjørnsen, Arve E.

    2014-01-01

    For the majority of the population, language is a left hemisphere lateralized function. During childhood, a pattern of increasing left lateralization for language has been described in brain imaging studies, suggesting this trait develops. This development could reflect change due to brain maturation or change due to skill acquisition, given that children acquire and refine language skills as they mature. We test the possibility that skill acquisition, independent of age-associated maturation can result in shifts in language lateralization in classic language cortex. We imaged adults exposed to unfamiliar language during three successive fMRI scans. Participants were then asked to identify specific words embedded in Norwegian sentences. Exposure to these sentences, relative to complex tones, resulted in consistent activation in the left and right superior temporal gyrus. Activation in this region became increasingly left lateralized with repeated exposure to the unfamiliar language. These results demonstrate that shifts in lateralization can be produced in the short-term within a learning context, independent of maturation. PMID:25285756

  15. Left is where the L is right. Significantly delayed reaction time in limb laterality recognition in both CRPS and phantom limb pain patients.

    Science.gov (United States)

    Reinersmann, Annika; Haarmeyer, Golo Sung; Blankenburg, Markus; Frettlöh, Jule; Krumova, Elena K; Ocklenburg, Sebastian; Maier, Christoph

    2010-12-17

    The body schema is based on an intact cortical body representation. Its disruption is indicated by delayed reaction times (RT) and high error rates when deciding on the laterality of a pictured hand in a limb laterality recognition task. Similarities in both cortical reorganisation and disrupted body schema have been found in two different unilateral pain syndromes, one with deafferentation (phantom limb pain, PLP) and one with pain-induced dysfunction (complex regional pain syndrome, CRPS). This study aims to compare the extent of impaired laterality recognition in these two groups. Performance on a test battery for attentional performance (TAP 2.0) and on a limb laterality recognition task was evaluated in CRPS (n=12), PLP (n=12) and healthy subjects (n=38). Differences between recognising affected and unaffected hands were analysed. CRPS patients and healthy subjects additionally completed a four-day training of limb laterality recognition. Reaction time was significantly delayed in both CRPS (2278±735.7ms) and PLP (2301.3±809.3ms) compared to healthy subjects (1826.5±517.0ms), despite normal TAP values in all groups. There were no differences between recognition of affected and unaffected hands in both patient groups. Both healthy subjects and CRPS patients improved during training, but RTs of CRPS patients (1874.5±613.3ms) remain slower (pCRPS patients, uninfluenced by attention and pain and cannot be fully reversed by training alone. This suggests the involvement of complex central nervous system mechanisms in the disruption of the body schema. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  16. Sheep laterality.

    Science.gov (United States)

    Anderson, Dean M; Murray, Leigh W

    2013-01-01

    Turning preferences among 309 white-faced ewes were individually evaluated in an enclosed, artificially lit T-maze, followed by each ewe choosing either a right or left return alley to return to peers. Data recorded included time in the start box, time in the T-maze, exit arm chosen to leave the T-maze, and return alley. Right and left arms of the T-maze were chosen 65.7% and 34.3% of the time, respectively, while right and left return alleys were chosen 32.4% and 67.6%, respectively. Exit arm and return alley were not independently chosen (p laterality was not related (α =.05) to time of day the test was administered, ewe's age or genetics, most recent liveweight, or most recent shorn fleece weight. The mean time spent in the start box (21 s) was not related to exit arm (p =.947) or return alley (p =.779). Mean time (15 s) spent in the T-maze was not related to exit arm (p =.086) or return alley (p =.952). More research will be required to understand sheep turning laterality and how it can impact working facilities and research equipment.

  17. Atypical handedness in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Doležalová, Irena; Schachter, Steven; Chrastina, Jan; Hemza, Jan; Hermanová, Markéta; Rektor, Ivan; Pažourková, Marta; Brázdil, Milan

    2017-07-01

    The main aim of our study was to investigate the handedness of patients with mesial temporal lobe epilepsy (MTLE). We also sought to identify clinical variables that correlated with left-handedness in this population. Handedness (laterality quotient) was assessed in 73 consecutive patients with MTLE associated with unilateral hippocampal sclerosis (HS) using the Edinburgh Handedness Inventory. Associations between right- and left-handedness and clinical variables were investigated. We found that 54 (74.0%) patients were right-handed, and 19 (26%) patients were left-handed. There were 15 (36.6%) left-handed patients with left-sided seizure onset compared to 4 (12.5%) left-handed patients with right-sided seizure onset (p=0.030). Among patients with left-sided MTLE, age at epilepsy onset was significantly correlated with handedness (8years of age [median; min-max 0.5-17] in left-handers versus 15years of age [median; min-max 3-30] in right-handers (p<0.001). Left-sided MTLE is associated with atypical handedness, especially when seizure onset occurs during an active period of brain development, suggesting a bi-hemispheric neuroplastic process for establishing motor dominance in patients with early-onset left-sided MTLE. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Dorsal anterior cingulate cortex in typically developing children: Laterality analysis

    Directory of Open Access Journals (Sweden)

    Jue Wang

    2015-10-01

    Full Text Available We aimed to elucidate the dACC laterality in typically developing children and their sex/age-related differences with a sample of 84 right-handed children (6–16 years, 42 boys. We first replicated the previous finding observed in adults that gray matter density asymmetry in the dACC was region-specific: leftward (left > right in its superior part, rightward (left < right in its inferior part. Intrinsic connectivity analysis of these regions further revealed region-specific asymmetric connectivity profiles in dACC as well as their sex and age differences. Specifically, the superior dACC connectivity with frontoparietal network and the inferior dACC connectivity with visual network are rightward. The superior dACC connectivity with the default network (lateral temporal cortex was more involved in the left hemisphere. In contrast, the inferior dACC connectivity with the default network (anterior medial prefrontal cortex was more lateralized towards the right hemisphere. The superior dACC connectivity with lateral visual cortex was more distinct across two hemispheres in girls than that in boys. This connection in boys changed with age from right-prominent to left-prominent asymmetry whereas girls developed the connection from left-prominent to no asymmetry. These findings not only highlight the complexity and laterality of the dACC but also provided insights into dynamical structure–function relationships during the development.

  19. Mapping a lateralization gradient within the ventral stream for auditory speech perception.

    Science.gov (United States)

    Specht, Karsten

    2013-01-01

    Recent models on speech perception propose a dual-stream processing network, with a dorsal stream, extending from the posterior temporal lobe of the left hemisphere through inferior parietal areas into the left inferior frontal gyrus, and a ventral stream that is assumed to originate in the primary auditory cortex in the upper posterior part of the temporal lobe and to extend toward the anterior part of the temporal lobe, where it may connect to the ventral part of the inferior frontal gyrus. This article describes and reviews the results from a series of complementary functional magnetic resonance imaging studies that aimed to trace the hierarchical processing network for speech comprehension within the left and right hemisphere with a particular focus on the temporal lobe and the ventral stream. As hypothesized, the results demonstrate a bilateral involvement of the temporal lobes in the processing of speech signals. However, an increasing leftward asymmetry was detected from auditory-phonetic to lexico-semantic processing and along the posterior-anterior axis, thus forming a "lateralization" gradient. This increasing leftward lateralization was particularly evident for the left superior temporal sulcus and more anterior parts of the temporal lobe.

  20. Efficient visual object and word recognition relies on high spatial frequency coding in the left posterior fusiform gyrus: evidence from a case-series of patients with ventral occipito-temporal cortex damage.

    Science.gov (United States)

    Roberts, Daniel J; Woollams, Anna M; Kim, Esther; Beeson, Pelagie M; Rapcsak, Steven Z; Lambon Ralph, Matthew A

    2013-11-01

    Recent visual neuroscience investigations suggest that ventral occipito-temporal cortex is retinotopically organized, with high acuity foveal input projecting primarily to the posterior fusiform gyrus (pFG), making this region crucial for coding high spatial frequency information. Because high spatial frequencies are critical for fine-grained visual discrimination, we hypothesized that damage to the left pFG should have an adverse effect not only on efficient reading, as observed in pure alexia, but also on the processing of complex non-orthographic visual stimuli. Consistent with this hypothesis, we obtained evidence that a large case series (n = 20) of patients with lesions centered on left pFG: 1) Exhibited reduced sensitivity to high spatial frequencies; 2) demonstrated prolonged response latencies both in reading (pure alexia) and object naming; and 3) were especially sensitive to visual complexity and similarity when discriminating between novel visual patterns. These results suggest that the patients' dual reading and non-orthographic recognition impairments have a common underlying mechanism and reflect the loss of high spatial frequency visual information normally coded in the left pFG.

  1. Seizure semiology identifies patients with bilateral temporal lobe epilepsy.

    Science.gov (United States)

    Loesch, Anna Mira; Feddersen, Berend; Tezer, F Irsel; Hartl, Elisabeth; Rémi, Jan; Vollmar, Christian; Noachtar, Soheyl

    2015-01-01

    Laterality in temporal lobe epilepsy is usually defined by EEG and imaging results. We investigated whether the analysis of seizure semiology including lateralizing seizure phenomena identifies bilateral independent temporal lobe seizure onset. We investigated the seizure semiology in 17 patients in whom invasive EEG-video-monitoring documented bilateral temporal seizure onset. The results were compared to 20 left and 20 right consecutive temporal lobe epilepsy (TLE) patients who were seizure free after anterior temporal lobe resection. The seizure semiology was analyzed using the semiological seizure classification with particular emphasis on the sequence of seizure phenomena over time and lateralizing seizure phenomena. Statistical analysis included chi-square test or Fisher's exact test. Bitemporal lobe epilepsy patients had more frequently different seizure semiology (100% vs. 40%; p<0.001) and significantly more often lateralizing seizure phenomena pointing to bilateral seizure onset compared to patients with unilateral TLE (67% vs. 11%; p<0.001). The sensitivity of identical vs. different seizure semiology for the identification of bilateral TLE was high (100%) with a specificity of 60%. Lateralizing seizure phenomena had a low sensitivity (59%) but a high specificity (89%). The combination of lateralizing seizure phenomena and different seizure semiology showed a high specificity (94%) but a low sensitivity (59%). The analysis of seizure semiology including lateralizing seizure phenomena adds important clinical information to identify patients with bilateral TLE. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Comparing Language Lateralization Determined by Dichotic Listening and fMRI Activation in Frontal and Temporal Lobes in Children with Epilepsy

    Science.gov (United States)

    Fernandes, M. A.; Smith, M. L.; Logan, W.; Crawley, A.; McAndrews, M. P.

    2006-01-01

    We investigated the relationship between ear advantage scores on the Fused Dichotic Words Test (FDWT), and laterality of activation in fMRI using a verb generation paradigm in fourteen children with epilepsy. The magnitude of the laterality index (LI), based on spatial extent and magnitude of activation in classical language areas (BA 44/45,…

  3. Effects of statistical quality, sampling rate and temporal filtering techniques on the extraction of functional parameters from the left ventricular time-activity curves

    Energy Technology Data Exchange (ETDEWEB)

    Guignard, P.A.; Chan, W. (Royal Melbourne Hospital, Parkville (Australia). Dept. of Nuclear Medicine)

    1984-09-01

    Several techniques for the processing of a series of curves derived from two left ventricular time-activity curves acquired at rest and during exercise with a nuclear stethoscope were evaluated. They were three and five point time smoothing. Fourier filtering preserving one to four harmonics (H), truncated curve Fourier filtering, and third degree polynomial curve fitting. Each filter's ability to recover, with fidelity, systolic and diastolic function parameters was evaluated under increasingly 'noisy' conditions and at several sampling rates. Third degree polynomial curve fittings and truncated Fourier filters exhibited very high sensitivity to noise. Three and five point time smoothing had moderate sensitivity to noise, but were highly affected by sampling rate. Fourier filtering preserving 2H or 3H produced the best compromise with high resilience to noise and independence of sampling rate as far as the recovery of these functional parameters is concerned.

  4. Effects of statistical quality, sampling rate and temporal filtering techniques on the extraction of functional parameters from the left ventricular time-activity curves

    International Nuclear Information System (INIS)

    Guignard, P.A.; Chan, W.

    1984-01-01

    Several techniques for the processing of a series of curves derived from two left ventricular time-activity curves acquired at rest and during exercise with a nuclear stethoscope were evaluated. They were three and five point time smoothing. Fourier filtering preserving one to four harmonics (H), truncated curve Fourier filtering, and third degree polynomial curve fitting. Each filter's ability to recover, with fidelity, systolic and diastolic function parameters was evaluated under increasingly 'noisy' conditions and at several sampling rates. Third degree polynomial curve fittings and truncated Fourier filters exhibited very high sensitivity to noise. Three and five point time smoothing had moderate sensitivity to noise, but were highly affected by sampling rate. Fourier filtering preserving 2H or 3H produced the best compromise with high resilience to noise and independence of sampling rate as far as the recovery of these functional parameters is concerned. (author)

  5. Comparisons of the Pentax-AWS, Glidescope, and Macintosh Laryngoscopes for Intubation Performance during Mechanical Chest Compressions in Left Lateral Tilt: A Randomized Simulation Study of Maternal Cardiopulmonary Resuscitation

    Directory of Open Access Journals (Sweden)

    Sanghyun Lee

    2015-01-01

    Full Text Available Purpose. Rapid advanced airway management is important in maternal cardiopulmonary resuscitation (CPR. This study aimed to compare intubation performances among Pentax-AWS (AWS, Glidescope (GVL, and Macintosh laryngoscope (MCL during mechanical chest compression in 15° and 30° left lateral tilt. Methods. In 19 emergency physicians, a prospective randomized crossover study was conducted to examine the three laryngoscopes. Primary outcomes were the intubation time and the success rate for intubation. Results. The median intubation time using AWS was shorter than that of GVL and MCL in both tilt degrees. The time to visualize the glottic view in GVL and AWS was significantly lower than that of MCL (all P<0.05, whereas there was no significant difference between the two video laryngoscopes (in 15° tilt, P=1; in 30° tilt, P=0.71. The progression of tracheal tube using AWS was faster than that of MCL and GVL in both degrees (all P<0.001. Intubations using AWS and GVL showed higher success rate than that of Macintosh laryngoscopes. Conclusions. The AWS could be an appropriate laryngoscope for airway management of pregnant women in tilt CPR considering intubation time and success rate.

  6. Arachnoid Pit and Extensive Sinus Pnematization as the Cause of Spontaneous Lateral Intrasphenoidal Encephalocele

    Directory of Open Access Journals (Sweden)

    Ali AlMontasheri

    2012-01-01

    Full Text Available Lateral sphenoid encephalocele, especially within the lateral aspect of the sphenoid sinus, when the sphenoid sinus has pneumatized extensively into the pterygoid recess, are considered exceedingly rare. We report a rare case of lateral intrasphenoidal encephalocele with spontaneous cerebral spinal fluid (CSF rhinorrhea. Computed tomography demonstrated bilateral arachnoid pit, extensive sphenoid sinus pneumatization, and a defect in the superior wall of the left lateral recess of the sphenoid sinus. Magnetic resonance imaging demonstrated anteromedial temporal lobe herniating through the bony defect.

  7. Cirurgia de revascularização do miocárdio através de minitoracotomia ântero-lateral esquerda Myocardial revascularization surgery through left anterolateral minithoracotomy

    Directory of Open Access Journals (Sweden)

    J. Glauco Lobo Filho

    1996-09-01

    Full Text Available No período de outubro de 1995 a fevereiro de 1996, 16 pacientes selecionados foram submetidos a cirurgia de revascularização do miocárdio através de minitoracotomia ântero-lateral esquerda. Em todos os casos a artéria torácica interna esquerda foi dissecada, para posterior anastomose com o ramo interventricular anterior (RIA sem a utilização de circulação extracorpórea. A idade variou de 43 a 77, com média de 60 anos. Sessenta e dois por cento dos pacientes eram do sexo masculino. Não houve complicações tais como: hemorragias, acidente vascular cerebral, insuficiência renal aguda, mediastinite ou infarto agudo do miocárdio. Não houve mortalidade no grupo em questão. Em 4 (25% pacientes foi realizado estudo hemodinâmico, que demostrou uma normalidade da anastomose da artéria torácica interna para o ramo interventricular anterior. Devido aos excelentes resultados iniciais, acreditamos que este procedimento possa ser empregado com maior freqüência e com a familiarização dos grupos cirúrgicos, e que as artérias diagonais e marginais da circunflexa possam ser beneficiadas com este tipo de procedimento.Between October 1995 and February 1996, sixteen patients were selected to undergo to surgical myocardial revascularization through left anterolateral minithoracotomy. The left internal thoracic artery was dissected in all patients, for consecutive anastomosis with interventricular anterior artery, without using extracorporeal circulation. Patients age ranged from 43 to 77, average 60 years. Sixty-two percent of them were men. There were no complications such as: acute myocardial infarction, mediastinitis, acute renal failure, hemorrhagy or stroke. There were no deaths. Four (25% patients were submitted to cardiac catheterization that showed patency of grafts and grafted native arteries. Due to excellent initial results, the authors believe that this technique can be employed with greater frequency and that its use can be

  8. Cognitive Functioning in Temporal Lobe Epilepsy: A BOLD-fMRI Study.

    Science.gov (United States)

    Guo, Lili; Bai, Genji; Zhang, Hui; Lu, Daoyan; Zheng, Jiyong; Xu, Gang

    2017-12-01

    We aimed to analyze the association between resting-state functional magnetic resonance imaging (re-fMRI) and cognitive function (including language, executive, and memory functions) in temporal lobe epilepsy (TLE) patients, which will help to explore the mechanism of brain function in patients. 15 TLE patients and 15 non-TLE patients were recruited. All subjects underwent neuropsychological testing and memory functional evaluation. Changes in verbal intelligence quotient (VIQ), performance intelligence quotient (PIQ), full intelligence quotient (FIQ), and memory quotient (MQ) were compared between two groups. Re-fMRI data were also collected from two groups to evaluate these changes. Each individual score of neuropsychological testing and memory functional evaluation were higher in control group, which was statistically different (all P temporal gyrus back, right superior temporal gyrus, left cerebellum, left angular gyrus, left wedge anterior lobe, and left central back; while the negatively activated brain regions were left prefrontal, right cerebellum, right corner back, and right anterior cingulate gyrus. During the language task, the activated brain regions of the TLE patients were right prefrontal lobe, the lateral temporal gyri, the left cerebellum, left cornu laterale gyrus, left precuneus, and the left postcentral gyrus, whereas the negatively activated brain areas were the left prefrontal cortex, the right cerebellum, right cornu laterale gyrus, and the right anterior cingulate gyrus. During the executive task, epilepsy patients showed activation difference in right prefrontal and right frontal lobe and right brain, left superior temporal gyrus, and right cerebellum anterior lobe compared with the control group; no negatively activated differences in brain areas. During the memory task, the difference lay in bilateral anterior cingulate gyrus and bilateral wedge anterior lobe while the negatively activated brain areas were the left inferior frontal

  9. Late Quaternary slip history of the Mill Creek strand of the San Andreas fault in San Gorgonio Pass, southern California: The role of a subsidiary left-lateral fault in strand switching

    Science.gov (United States)

    Kendrick, Katherine J.; Matti, Jonathan; Mahan, Shannon

    2015-01-01

    The fault history of the Mill Creek strand of the San Andreas fault (SAF) in the San Gorgonio Pass region, along with the reconstructed geomorphology surrounding this fault strand, reveals the important role of the left-lateral Pinto Mountain fault in the regional fault strand switching. The Mill Creek strand has 7.1–8.7 km total slip. Following this displacement, the Pinto Mountain fault offset the Mill Creek strand 1–1.25 km, as SAF slip transferred to the San Bernardino, Banning, and Garnet Hill strands. An alluvial complex within the Mission Creek watershed can be linked to palinspastic reconstruction of drainage segments to constrain slip history of the Mill Creek strand. We investigated surface remnants through detailed geologic mapping, morphometric and stratigraphic analysis, geochronology, and pedogenic analysis. The degree of soil development constrains the duration of surface stability when correlated to other regional, independently dated pedons. This correlation indicates that the oldest surfaces are significantly older than 500 ka. Luminescence dates of 106 ka and 95 ka from (respectively) 5 and 4 m beneath a younger fan surface are consistent with age estimates based on soil-profile development. Offset of the Mill Creek strand by the Pinto Mountain fault suggests a short-term slip rate of ∼10–12.5 mm/yr for the Pinto Mountain fault, and a lower long-term slip rate. Uplift of the Yucaipa Ridge block during the period of Mill Creek strand activity is consistent with thermochronologic modeled uplift estimates.

  10. [Left-handedness and health].

    Science.gov (United States)

    Milenković, Sanja; Belojević, Goran; Kocijancić, Radojka

    2010-01-01

    Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome), developmental disorders (autism, dislexia and sttutering) and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about "anomalous" cerebral domination, as a consequence of hormonal disbalance.

  11. Non-compact left ventricle/hypertrabeculated left ventricle

    International Nuclear Information System (INIS)

    Restrepo, Gustavo; Castano, Rafael; Marmol, Alejandro

    2005-01-01

    Non-compact left ventricle/hypertrabeculated left ventricle is a myocardiopatie produced by an arrest of the normal left ventricular compaction process during the early embryogenesis. It is associated to cardiac anomalies (congenital cardiopaties) as well as to extracardial conditions (neurological, facial, hematologic, cutaneous, skeletal and endocrinological anomalies). This entity is frequently unnoticed, being diagnosed only in centers with great experience in the diagnosis and treatment of myocardiopathies. Many cases of non-compact left ventricle have been initially misdiagnosed as hypertrophic myocardiopatie, endocardial fibroelastosis, dilated cardiomyopatie, restrictive cardiomyopathy and endocardial fibrosis. It is reported the case of a 74 years old man with a history of chronic arterial hypertension and diabetes mellitus, prechordial chest pain and mild dyspnoea. An echocardiogram showed signs of non-compact left ventricle with prominent trabeculations and deep inter-trabecular recesses involving left ventricular apical segment and extending to the lateral and inferior walls. Literature on this topic is reviewed

  12. Chondroblastoma of temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Tanohta, K.; Noda, M.; Katoh, H.; Okazaki, A.; Sugiyama, S.; Maehara, T.; Onishi, S.; Tanida, T.

    1986-07-01

    The case of a 55-year-old female with chondroblastoma arising from the left temporal bone is presented. Although 10 cases of temporal chondroblastoma have been reported, this is the first in which plain radiography, pluridirectional tomography, computed tomography (CT) and angiography were performed. We discuss the clinical and radiological aspects of this rare tumor.

  13. Chondroblastoma of temporal bone

    International Nuclear Information System (INIS)

    Tanohta, K.; Noda, M.; Katoh, H.; Okazaki, A.; Sugiyama, S.; Maehara, T.; Onishi, S.; Tanida, T.

    1986-01-01

    The case of a 55-year-old female with chondroblastoma arising from the left temporal bone is presented. Although 10 cases of temporal chondroblastoma have been reported, this is the first in which plain radiography, pluridirectional tomography, computed tomography (CT) and angiography were performed. We discuss the clinical and radiological aspects of this rare tumor. (orig.)

  14. Cortical Activation during a Cognitive Challenge in Patients with Chronic Temporal Lobe Epilepsy—A Dynamic SPECT Study

    Directory of Open Access Journals (Sweden)

    P. J. Kirkpatrick

    1993-01-01

    Full Text Available In a pilot group of six patients suffering from chronic temporal lobe epilepsy, single photon emission computerized tomography (SPECT has been used to image the changes in relative cerebral blood flow between rest (static scan and conditions of cognitive activation (activated scan. The cognitive challenge used during activation comprised a test of word memory, and the performance was expressed as a word memory score (WMS for each individual. An activation index (AI was calculated from the mean normalized density counts in specific regions of interest (ROIs, and values obtained were analysed for correlation with the WMS. The mean AI was increased significantly in the right lateral temporal cortex, the right and left inferior frontal regions, the left temporal pole, and the right medial temporal cortex. A positive correlation with the WMS was found in the medial temporal cortices, and this relationship was significant for the right medial temporal ROI.

  15. Memory of music: roles of right hippocampus and left inferior frontal gyrus.

    Science.gov (United States)

    Watanabe, Takamitsu; Yagishita, Sho; Kikyo, Hideyuki

    2008-01-01

    We investigated neural correlates of retrieval success for music memory using event-related functional magnetic resonance imaging. To minimize the interference from MRI scan noise, we used sparse temporal sampling technique. Newly composed music materials were employed as stimuli, which enabled us to detect regions in absence of effects of experience with the music stimuli in this study. Whole brain analyses demonstrated significant retrieval success activities in the right hippocampus, bilateral lateral temporal regions, left inferior frontal gyrus and left precuneus. Anatomically defined region-of-interests analyses showed that the activity of the right hippocampus was stronger than that of the left, while the activities of the inferior frontal gyri showed the reverse pattern. Furthermore, performance-based analyses demonstrated that the retrieval success activity of the right hippocampus was positively correlated with the corrected recognition rate, suggesting that the right hippocampus contributes to the accuracy of music retrieval outcome.

  16. Activation of the left inferior frontal gyrus in the first 200 ms of reading: evidence from magnetoencephalography (MEG).

    Science.gov (United States)

    Cornelissen, Piers L; Kringelbach, Morten L; Ellis, Andrew W; Whitney, Carol; Holliday, Ian E; Hansen, Peter C

    2009-01-01

    It is well established that the left inferior frontal gyrus plays a key role in the cerebral cortical network that supports reading and visual word recognition. Less clear is when in time this contribution begins. We used magnetoencephalography (MEG), which has both good spatial and excellent temporal resolution, to address this question. MEG data were recorded during a passive viewing paradigm, chosen to emphasize the stimulus-driven component of the cortical response, in which right-handed participants were presented words, consonant strings, and unfamiliar faces to central vision. Time-frequency analyses showed a left-lateralized inferior frontal gyrus (pars opercularis) response to words between 100-250 ms in the beta frequency band that was significantly stronger than the response to consonant strings or faces. The left inferior frontal gyrus response to words peaked at approximately 130 ms. This response was significantly later in time than the left middle occipital gyrus, which peaked at approximately 115 ms, but not significantly different from the peak response in the left mid fusiform gyrus, which peaked at approximately 140 ms, at a location coincident with the fMRI-defined visual word form area (VWFA). Significant responses were also detected to words in other parts of the reading network, including the anterior middle temporal gyrus, the left posterior middle temporal gyrus, the angular and supramarginal gyri, and the left superior temporal gyrus. These findings suggest very early interactions between the vision and language domains during visual word recognition, with speech motor areas being activated at the same time as the orthographic word-form is being resolved within the fusiform gyrus. This challenges the conventional view of a temporally serial processing sequence for visual word recognition in which letter forms are initially decoded, interact with their phonological and semantic representations, and only then gain access to a speech code.

  17. Temporal and extra-temporal hypoperfusion in medial temporal lobe epilepsy evaluated by arterial-spin-labeling based MRI

    International Nuclear Information System (INIS)

    Shen Lianfang; Zhang Zhiqiang; Lu Guangming; Yuan Cuiping; Wang Zhengge; Wang Haoxue; Huang Wei; Wei Fangyuan; Chen Guanghui; Tan Qifu

    2012-01-01

    Objective: To evaluate the feasibility of the lateralization of unilateral medial temporal lobe epilepsy (mTLE) by using arterial-spin-labeling (ASL) based perfusion MR imaging and investigate the changes of perfusion in the regions related to mTLE network and the relationship between the perfusion and the clinical status. Methods: Twenty-five patients with left-sided and 23 with right-sided mTLE were enrolled, and 30 healthy volunteers were recruited. The cerebral blood flow (CBF) of related region was measured based on pulsed-ASL sequence on Siemens 3 T scanner. The CBF of the mTLE group were compared with that in the controls by using ANOVA analysis. The asymmetric indices of CBF in the medial temporal lobe were calculated as the lesion side compared with the normal side in matched region in mTLE group. Results: Compared with the volunteers, the patients with mTLE showed the decrease of CBF in the bilateral medial and lateral temporal, the frontal and parietal regions relating to the default-mode network and more serious in lesion side. The CBF values of the medial temporal lobe were negatively correlated with the epilepsy duration (r=-0.51, P<0.01). The asymmetric index of CBF as-0.01 has a 76.0% (19/25) sensitivity and a 78.3% (18/23) specificity to distinguish the lesion side. Conclusions: The decrease of CBF in the temporal and extra-temporal region by ASL-based MRI suggests the functional abnormalities in the network involved by mTLE. The ASL technique is a useful tool for lateralizing the unilateral mTLE. (authors)

  18. Cerebral Laterality and Verbal Processes

    Science.gov (United States)

    Sherman, Jay L.; And Others

    1976-01-01

    Research suggests that we process information by way of two distinct and functionally separate coding systems. Their location, somewhat dependent on cerebral laterality, varies in right- and left-handed persons. Tests this dual coding model. (Editor/RK)

  19. Temporal lobe volume predicts Wada memory test performance in patients with mesial temporal sclerosis.

    Science.gov (United States)

    Ding, Kan; Gong, Yunhua; Modur, Pradeep N; Diaz-Arrastia, Ramon; Agostini, Mark; Gupta, Puneet; McColl, Roderick; Hays, Ryan; Van Ness, Paul

    2016-02-01

    The Wada test is widely used in the presurgical evaluation of potential temporal lobectomy patients to predict postoperative memory function. Expected asymmetry (EA), defined as Wada memory lateralized to the nonsurgical hemisphere, or a higher score after injection of the surgical hemisphere would be considered favorable in terms of postoperative memory outcome. However, in some cases, nonlateralized memory (NM) results, with no appreciable asymmetry, may occur because of impaired scores after both injections, often leading to denial of surgery. The reason for such nonlateralized Wada memory in patients with intractable temporal lobe epilepsy (TLE) remains unclear. Given that quantitative morphometric magnetic resonance imaging studies in TLE patients have shown bilateral regional atrophy in temporal and extratemporal structures, we hypothesized that the volume loss in contralateral temporal structures could contribute to nonlateralized Wada memory performance. To investigate this, we examined the relationship between the volume changes of temporal structures and Wada memory scores in patients with intractable TLE with mesial temporal sclerosis (MTS) using an age- and gender-matched control group. Memory was considered nonlateralized if the absolute difference in the total correct recall scores between ipsilateral and contralateral injections was memory was lateralized in 15 and nonlateralized in 6 patients, with all the nonlateralized scores being observed in left TLE. The recall scores after ipsilateral injection were significantly lower in patients with an NM profile than an EA profile (23 ± 14% vs. 59 ± 18% correct recall, p ≤ 0.001). However, the recall scores after contralateral injection were low but similar between the two groups (25 ± 17% vs. 25 ± 15% correct recall, p=0.97). Compared to controls, all the patients showed greater volume loss in the temporal regions. However, patients with a NM profile showed significantly more volume loss than those

  20. Arteriovenous Malformation in Temporal Lobe Presenting as Contralateral Ocular Symptoms Mimicking Carotid-Cavernous Fistula

    Directory of Open Access Journals (Sweden)

    Fadzillah Mohd-Tahir

    2013-01-01

    Full Text Available Aim. To report a rare case of arteriovenous malformation in temporal lobe presenting as contralateral orbital symptoms mimicking carotid-cavernous fistula. Method. Interventional case report. Results. A 31-year-old Malay gentleman presented with 2-month history of painful progressive exophthalmos of his left eye associated with recurrent headache, diplopia, and reduced vision. Ocular examination revealed congestive nonpulsating 7 mm exophthalmos of the left eye with no restriction of movements in all direction. There was diplopia in left lateral gaze. Left IOP was elevated at 29 mmHg. Left eye retinal vessels were slightly dilated and tortuous. CT scan was performed and showed right temporal arteriovenous malformation with a nidus of 3.8 cm × 2.5 cm with right middle cerebral artery as feeding artery. There was dilated left superior ophthalmic vein of 0.9 mm in diameter with enlarged left cavernous sinus. MRA and carotid angiogram confirmed right temporal arteriovenous malformation with no carotid-cavernous fistula. Most of the intracranial drainage was via left cavernous sinus. His signs and symptoms dramatically improved following successful embolisation, completely resolved after one year. Conclusion. Intracranial arteriovenous malformation is rarely presented with primary ocular presentation. Early intervention would salvage the eyes and prevent patients from more disaster morbidity or fatality commonly due to intracranial haemorrhage.

  1. Reorganization of syntactic processing following left-hemisphere brain damage: does right-hemisphere activity preserve function?

    Science.gov (United States)

    Tyler, Lorraine K; Wright, Paul; Randall, Billi; Marslen-Wilson, William D; Stamatakis, Emmanuel A

    2010-11-01

    The extent to which the human brain shows evidence of functional plasticity across the lifespan has been addressed in the context of pathological brain changes and, more recently, of the changes that take place during healthy ageing. Here we examine the potential for plasticity by asking whether a strongly left-lateralized system can successfully reorganize to the right-hemisphere following left-hemisphere brain damage. To do this, we focus on syntax, a key linguistic function considered to be strongly left-lateralized, combining measures of tissue integrity, neural activation and behavioural performance. In a functional neuroimaging study participants heard spoken sentences that differentially loaded on syntactic and semantic information. While healthy controls activated a left-hemisphere network of correlated activity including Brodmann areas 45/47 and posterior middle temporal gyrus during syntactic processing, patients activated Brodmann areas 45/47 bilaterally and right middle temporal gyrus. However, voxel-based morphometry analyses showed that only tissue integrity in left Brodmann areas 45/47 was correlated with activity and performance; poor tissue integrity in left Brodmann area 45 was associated with reduced functional activity and increased syntactic deficits. Activity in the right-hemisphere was not correlated with damage in the left-hemisphere or with performance. Reduced neural integrity in the left-hemisphere through brain damage or healthy ageing results in increased right-hemisphere activation in homologous regions to those left-hemisphere regions typically involved in the young. However, these regions do not support the same linguistic functions as those in the left-hemisphere and only indirectly contribute to preserved syntactic capacity. This establishes the unique role of the left hemisphere in syntax, a core component in human language.

  2. Functional magnetic resonance imaging (fMRI) in patients with gliomas adjacent to classical language areas. Lateralization of activated prefrontal cortex is important in determining the dominant hemisphere

    International Nuclear Information System (INIS)

    Karibe, Hiroshi; Kumabe, Toshihiro; Shirane, Reizo; Yoshimoto, Takashi

    2003-01-01

    In patients with gliomas adjacent to classical language areas, lateralized activation of prefrontal cortex was assessed to determine language dominant hemisphere using functional magnetic resonance imaging (fMRI). Twelve patients presented with aphasias were studied. In all patients, either the left frontal operculum or left superior temporal gyri were adjacent to gliomas, suggesting all patients had left lateralization in hemispheric language dominance. Functional MRI was performed with a 1.5T scanner, with the sequence of gradient-echo type echo-planar imaging. As specific language tasks, verb, word, and capping generations were used. Using a cross-correlation analysis method, primary activation maps were generated using pixels with a correlation coefficient of >0.7. The lateralized activation of frontal operculum, superior temporal gyrus, and prefrontal cortex were assessed by calculating laterality index. Successful activation of frontal operculum was imaged in 11 of 12, in the superior temporal gyrus or prefrontal cortex. Three out of 11 cases had apparent activation lateralized in the right frontal operculum on fMRI, while 3 out of 12 cases showed activation in the superior temporal gyrus. On the other hand, all cases had apparent activation lateralized to the left prefrontal cortex. Significant activation of true language area may not be obtained in some cases with gliomas adjacent to classical language areas. In such cases, lateralization of apparent activation of prefrontal cortex may reflect lateralization in the dominant hemisphere. These result suggest that the assessment of apparent activation of prefrontal cortex lateralization is useful to determine the language dominant hemisphere. (author)

  3. Left-handedness and health

    Directory of Open Access Journals (Sweden)

    Milenković Sanja

    2010-01-01

    Full Text Available Hand dominance is defined as a proneness to use one hand rather than another in performing the majority of activities and this is the most obvious example of cerebral lateralization and an exclusive human characteristic. Left-handed people comprise 6-14% of the total population, while in Serbia, this percentage is 5-10%, moving from undeveloped to developed environments, where a socio-cultural pressure is less present. There is no agreement between investigators who in fact may be considered a left-handed person, about the percentage of left-handers in the population and about the etiology of left-handedness. In the scientific literature left-handedness has been related to health disorders (spine deformities, immunological disorders, migraine, neurosis, depressive psychosis, schizophrenia, insomnia, homosexuality, diabetes mellitus, arterial hypertension, sleep apnea, enuresis nocturna and Down Syndrome, developmental disorders (autism, dislexia and sttutering and traumatism. The most reliable scientific evidences have been published about the relationship between left-handedness and spinal deformities in school children in puberty and with traumatism in general population. The controversy of other results in up-to-now investigations of health aspects of left-handedness may partly be explained by a scientific disagreement whether writing with the left hand is a sufficient criterium for left-handedness, or is it necessary to investigate other parameters for laterality assessment. Explanation of health aspects of left-handedness is dominantly based on Geschwind-Galaburda model about 'anomalous' cerebral domination, as a consequence of hormonal disbalance. .

  4. Selective attention to phonology dynamically modulates initial encoding of auditory words within the left hemisphere.

    Science.gov (United States)

    Yoncheva, Yuliya; Maurer, Urs; Zevin, Jason D; McCandliss, Bruce D

    2014-08-15

    Selective attention to phonology, i.e., the ability to attend to sub-syllabic units within spoken words, is a critical precursor to literacy acquisition. Recent functional magnetic resonance imaging evidence has demonstrated that a left-lateralized network of frontal, temporal, and posterior language regions, including the visual word form area, supports this skill. The current event-related potential (ERP) study investigated the temporal dynamics of selective attention to phonology during spoken word perception. We tested the hypothesis that selective attention to phonology dynamically modulates stimulus encoding by recruiting left-lateralized processes specifically while the information critical for performance is unfolding. Selective attention to phonology was captured by manipulating listening goals: skilled adult readers attended to either rhyme or melody within auditory stimulus pairs. Each pair superimposed rhyming and melodic information ensuring identical sensory stimulation. Selective attention to phonology produced distinct early and late topographic ERP effects during stimulus encoding. Data-driven source localization analyses revealed that selective attention to phonology led to significantly greater recruitment of left-lateralized posterior and extensive temporal regions, which was notably concurrent with the rhyme-relevant information within the word. Furthermore, selective attention effects were specific to auditory stimulus encoding and not observed in response to cues, arguing against the notion that they reflect sustained task setting. Collectively, these results demonstrate that selective attention to phonology dynamically engages a left-lateralized network during the critical time-period of perception for achieving phonological analysis goals. These findings suggest a key role for selective attention in on-line phonological computations. Furthermore, these findings motivate future research on the role that neural mechanisms of attention may

  5. Selective attention to phonology dynamically modulates initial encoding of auditory words within the left hemisphere

    Science.gov (United States)

    Yoncheva; Maurer, Urs; Zevin, Jason; McCandliss, Bruce

    2015-01-01

    Selective attention to phonology, i.e., the ability to attend to sub-syllabic units within spoken words, is a critical precursor to literacy acquisition. Recent functional magnetic resonance imaging evidence has demonstrated that a left-lateralized network of frontal, temporal, and posterior language regions, including the visual word form area, supports this skill. The current event-related potential (ERP) study investigated the temporal dynamics of selective attention to phonology during spoken word perception. We tested the hypothesis that selective atten tion to phonology dynamically modulates stimulus encoding by recruiting left-lateralized processes specifically while the information critical for performance is unfolding. Selective attention to phonology was captured by ma nipulating listening goals: skilled adult readers attended to either rhyme or melody within auditory stimulus pairs. Each pair superimposed rhyming and melodic information ensuring identical sensory stimulation. Selective attention to phonology produced distinct early and late topographic ERP effects during stimulus encoding. Data- driven source localization analyses revealed that selective attention to phonology led to significantly greater re cruitment of left-lateralized posterior and extensive temporal regions, which was notably concurrent with the rhyme-relevant information within the word. Furthermore, selective attention effects were specific to auditory stimulus encoding and not observed in response to cues, arguing against the notion that they reflect sustained task setting. Collectively, these results demonstrate that selective attention to phonology dynamically engages a left-lateralized network during the critical time-period of perception for achieving phonological analysis goals. These findings support the key role of selective attention to phonology in the development of literacy and motivate future research on the neural bases of the interaction between phonological

  6. Three cases of temporal bone osteoradionecrosis after nasopharyngeal carcinoma treatment

    International Nuclear Information System (INIS)

    Yamatodani, Takashi; Mizuta, Kunihiro; Nakanishi, Hiroshi; Takizawa, Yoshinori; Hosokawa, Kumiko; Hosokawa, Seiji; Mineta, Hiroyuki

    2012-01-01

    Osteoradionecrosis is most commonly caused by radiation-induced injury. We report on 3 cases of temporal bone necrosis that occurred after chemoradiotherapy for nasopharyngeal carcinoma performed more than 10 years previously. Case 1 was a 42-year-old woman who had nasopharyngeal carcinoma in 1991. The patient underwent chemoradiotherapy (70 Gy total) in 1991, and gamma knife irradiation (20 Gy) in 1998 for local recurrence. The bone in the posterior wall of the left external auditory canal began to be exposed in 2003. Otorrhea from the left ear increased and we found a skin defect and ulcer formation in the postauricular region. We performed radical mastoidectomy and debridement on April, 2010. The area of the defect was covered and filled in with a pedicle musculoperiosteal flap. The intra-aural skin became dry in 6 months, however, she lost consciousness due to a temporal lobe abscess and underwent an emergency operation on April, 2011. After operation, the patient recovered with no neurological symptoms and infections up to the present date. Case 2 was a 58-year-old man who had nasopharyngeal carcinoma in 2001. The patient underwent chemoradiotherapy (66 Gy total) in 2001, and X knife irradiation (15 Gy) 3 months later due to the remaining tumor. The left posterior ear canal wall collapsed and the tympanic membrane retracted with pooling epithelial debris appearing in 2007. Left facial nerve palsy was seen in December 2010. We performed a mastoidectomy on January, 2011. Cholesteatoma and necrotic granuloma with fragile bone filled the mastoid cavity, and a facial canal bone defect was seen. Bone necrosis with cholesteatoma and inflammatory granuloma was revealed by the pathological examination. The facial palsy improved after the operation. Case 3 was a 59-year-old man who had left abducens palsy with nasopharyngeal carcinoma invading the clivus. The patient underwent chemoradiotherapy (60 Gy total) in 2001, and X knife irradiation (24 Gy) 4 months later for

  7. Preventing Errors in Laterality

    OpenAIRE

    Landau, Elliot; Hirschorn, David; Koutras, Iakovos; Malek, Alexander; Demissie, Seleshie

    2014-01-01

    An error in laterality is the reporting of a finding that is present on the right side as on the left or vice versa. While different medical and surgical specialties have implemented protocols to help prevent such errors, very few studies have been published that describe these errors in radiology reports and ways to prevent them. We devised a system that allows the radiologist to view reports in a separate window, displayed in a simple font and with all terms of laterality highlighted in sep...

  8. Lateral Concepts

    DEFF Research Database (Denmark)

    Gad, Christopher; Bruun Jensen, casper

    2016-01-01

    This essay discusses the complex relation between the knowledges and practices of the researcher and his/her informants in terms of lateral concepts. The starting point is that it is not the prerogative of the (STS) scholar to conceptualize the world; all our “informants” do it too. This creates...... the possibility of enriching our own conceptual repertoires by letting them be inflected by the concepts of those we study. In a broad sense, the lateral means that there is a many-to-many relation between domains of knowledge and practice. However, each specific case of the lateral is necessarily immanent...... to a particular empirical setting and form of inquiry. In this sense lateral concepts are radically empirical since it locates concepts within the field. To clarify the meaning and stakes of lateral concepts, we first make a contrast between lateral anthropology and Latour’s notion of infra-reflexivity. We end...

  9. Right hemispheric contributions to fine auditory temporal discriminations: high-density electrical mapping of the duration mismatch negativity (MMN

    Directory of Open Access Journals (Sweden)

    Pierfilippo De Sanctis

    2009-04-01

    Full Text Available That language processing is primarily a function of the left hemisphere has led to the supposition that auditory temporal discrimination is particularly well-tuned in the left hemisphere, since speech discrimination is thought to rely heavily on the registration of temporal transitions. However, physiological data have not consistently supported this view. Rather, functional imaging studies often show equally strong, if not stronger, contributions from the right hemisphere during temporal processing tasks, suggesting a more complex underlying neural substrate. The mismatch negativity (MMN component of the human auditory evoked-potential (AEP provides a sensitive metric of duration processing in human auditory cortex and lateralization of MMN can be readily assayed when sufficiently dense electrode arrays are employed. Here, the sensitivity of the left and right auditory cortex for temporal processing was measured by recording the MMN to small duration deviants presented to either the left or right ear. We found that duration deviants differing by just 15% (i.e. rare 115 ms tones presented in a stream of 100 ms tones elicited a significant MMN for tones presented to the left ear (biasing the right hemisphere. However, deviants presented to the right ear elicited no detectable MMN for this separation. Further, participants detected significantly more duration deviants and committed fewer false alarms for tones presented to the left ear during a subsequent psychophysical testing session. In contrast to the prevalent model, these results point to equivalent if not greater right hemisphere contributions to temporal processing of small duration changes.

  10. Quality of life in childhood epilepsy with lateralized epileptogenic foci.

    Science.gov (United States)

    Mathiak, Krystyna A; Luba, Małgorzata; Mathiak, Klaus; Karzel, Katarzyna; Wolańczyk, Tomasz; Szczepanik, Elzbieta; Ostaszewski, Paweł

    2010-08-17

    Measuring quality of life (QOL) helps to delineate mechanisms underlying the interaction of disease and psychosocial factors. In adults, epileptic foci in the left temporal lobe led to lower QOL and higher depression and anxiety as compared to the right-sided foci. No study addressed the development of QOL disturbances depending on the lateralization of epileptogenic focus. The objective of our study was to examine QOL in children with lateralized epileptiform discharges. Thirty-one parents of children with epilepsy filled the Health-Related Quality of Life in Childhood Epilepsy Questionnaire (QOLCE). Fifteen children had foci in the left hemisphere and sixteen in the right, as verified with Electroencephalography (EEG) examinations. We found a significant correlation between foci lateralization and reduced QOL (Spearman's rho = 0.361, p < 0.046). Children with right hemispheric foci exhibited lower overall QOL, particularly in five areas: anxiety, social-activities, stigma, general-health, and quality-of-life. We demonstrated for the first time that in children left- and right-hemispheric foci were associated with discordant QOL scores. Unlike in adults, foci in the right hemisphere led to worse emotional and social functioning demonstrating that seizures impact the brain differentially during development.

  11. Quality of life in childhood epilepsy with lateralized epileptogenic foci

    Directory of Open Access Journals (Sweden)

    Mathiak Krystyna A

    2010-08-01

    Full Text Available Abstract Background Measuring quality of life (QOL helps to delineate mechanisms underlying the interaction of disease and psychosocial factors. In adults, epileptic foci in the left temporal lobe led to lower QOL and higher depression and anxiety as compared to the right-sided foci. No study addressed the development of QOL disturbances depending on the lateralization of epileptogenic focus. The objective of our study was to examine QOL in children with lateralized epileptiform discharges. Methods Thirty-one parents of children with epilepsy filled the Health-Related Quality of Life in Childhood Epilepsy Questionnaire (QOLCE. Fifteen children had foci in the left hemisphere and sixteen in the right, as verified with Electroencephalography (EEG examinations. Results We found a significant correlation between foci lateralization and reduced QOL (Spearman's rho = 0.361, p Conclusions We demonstrated for the first time that in children left- and right-hemispheric foci were associated with discordant QOL scores. Unlike in adults, foci in the right hemisphere led to worse emotional and social functioning demonstrating that seizures impact the brain differentially during development.

  12. Determination of language lateralization using functional MRI during the performance of shiritori tasks in neurosurgery patients

    International Nuclear Information System (INIS)

    Takayama, Hideichi; Kobayashi, Masahito; Sugishita, Morihiro; Onozuka, Satoshi; Kawase, Takeshi

    2001-01-01

    Assessment of language lateralization is crucial in patients considered for neurological surgery. The authors used functional MRI (fMRI) in conjunction with shiritori, a kind of word-generation task as paradigms, to determine language lateralization in the patients. We used a 1.5 Tesla magnetic resonance imaging devise with an echo-planar imaging sequence. Thirty-two patients undergoing neurological surgery would alternately rest and silently perform shiritori during fMRI acquisition. Language lateralization was determined in 29 out of 32 patients. Twenty-two patients were considered as left-hemisphere dominant and seven were right-hemisphere dominant. Brain activation was seen in the prefrontal area, premotor area, superior temporal gyrus and parietal lobe of the dominant hemisphere, which is consistent with the results in normal adults. Language lateralization was particularly useful in a case of meningioma in the left lateral ventricle and in a case of AVM in the left temporoparietal region. fMRI with shiritori tasks revealed right-hemisphere dominance in both cases, which was also confirmed by intracarotid amobarbital (Wada) testing. Both lesions were treated successfully without causing any further deficit to the patients' language function. These results suggest that fMRI with shiritori tasks can be used to assess language lateralization non-invasively, compared with the current techniques, such as intracarotid amobarbital testing and cortical electrostimulation mapping. Thus, fMRI with shiritori tasks has significant clinical potential as a presurgical evaluation tool. (author)

  13. Determination of language lateralization using functional MRI during the performance of shiritori tasks in neurosurgery patients

    Energy Technology Data Exchange (ETDEWEB)

    Takayama, Hideichi; Kobayashi, Masahito [Mihara Memorial Hospital, Isesaki, Gunma (Japan); Sugishita, Morihiro; Onozuka, Satoshi; Kawase, Takeshi

    2001-03-01

    Assessment of language lateralization is crucial in patients considered for neurological surgery. The authors used functional MRI (fMRI) in conjunction with shiritori, a kind of word-generation task as paradigms, to determine language lateralization in the patients. We used a 1.5 Tesla magnetic resonance imaging devise with an echo-planar imaging sequence. Thirty-two patients undergoing neurological surgery would alternately rest and silently perform shiritori during fMRI acquisition. Language lateralization was determined in 29 out of 32 patients. Twenty-two patients were considered as left-hemisphere dominant and seven were right-hemisphere dominant. Brain activation was seen in the prefrontal area, premotor area, superior temporal gyrus and parietal lobe of the dominant hemisphere, which is consistent with the results in normal adults. Language lateralization was particularly useful in a case of meningioma in the left lateral ventricle and in a case of AVM in the left temporoparietal region. fMRI with shiritori tasks revealed right-hemisphere dominance in both cases, which was also confirmed by intracarotid amobarbital (Wada) testing. Both lesions were treated successfully without causing any further deficit to the patients' language function. These results suggest that fMRI with shiritori tasks can be used to assess language lateralization non-invasively, compared with the current techniques, such as intracarotid amobarbital testing and cortical electrostimulation mapping. Thus, fMRI with shiritori tasks has significant clinical potential as a presurgical evaluation tool. (author)

  14. Temporal lobe surgery in childhood and neuroanatomical predictors of long-term declarative memory outcome

    Science.gov (United States)

    Skirrow, Caroline; Cross, J. Helen; Harrison, Sue; Cormack, Francesca; Harkness, William; Coleman, Rosie; Meierotto, Ellen; Gaiottino, Johanna; Vargha-Khadem, Faraneh

    2015-01-01

    The temporal lobes play a prominent role in declarative memory function, including episodic memory (memory for events) and semantic memory (memory for facts and concepts). Surgical resection for medication-resistant and well-localized temporal lobe epilepsy has good prognosis for seizure freedom, but is linked to memory difficulties in adults, especially when the removal is on the left side. Children may benefit most from surgery, because brain plasticity may facilitate post-surgical reorganization, and seizure cessation may promote cognitive development. However, the long-term impact of this intervention in children is not known. We examined memory function in 53 children (25 males, 28 females) who were evaluated for epilepsy surgery: 42 underwent unilateral temporal lobe resections (25 left, 17 right, mean age at surgery 13.8 years), 11 were treated only pharmacologically. Average follow-up was 9 years (range 5–15). Post-surgical change in visual and verbal episodic memory, and semantic memory at follow-up were examined. Pre- and post-surgical T1-weighted MRI brain scans were analysed to extract hippocampal and resection volumes, and evaluate post-surgical temporal lobe integrity. Language lateralization indices were derived from functional magnetic resonance imaging. There were no significant pre- to postoperative decrements in memory associated with surgery. In contrast, gains in verbal episodic memory were seen after right temporal lobe surgery, and visual episodic memory improved after left temporal lobe surgery, indicating a functional release in the unoperated temporal lobe after seizure reduction or cessation. Pre- to post-surgical change in memory function was not associated with any indices of brain structure derived from MRI. However, better verbal memory at follow-up was linked to greater post-surgical residual hippocampal volumes, most robustly in left surgical participants. Better semantic memory at follow-up was associated with smaller resection

  15. Time left in the mouse.

    Science.gov (United States)

    Cordes, Sara; King, Adam Philip; Gallistel, C R

    2007-02-22

    Evidence suggests that the online combination of non-verbal magnitudes (durations, numerosities) is central to learning in both human and non-human animals [Gallistel, C.R., 1990. The Organization of Learning. MIT Press, Cambridge, MA]. The molecular basis of these computations, however, is an open question at this point. The current study provides the first direct test of temporal subtraction in a species in which the genetic code is available. In two experiments, mice were run in an adaptation of Gibbon and Church's [Gibbon, J., Church, R.M., 1981. Time left: linear versus logarithmic subjective time. J. Exp. Anal. Behav. 7, 87-107] time left paradigm in order to characterize typical responding in this task. Both experiments suggest that mice engaged in online subtraction of temporal values, although the generalization of a learned response rule to novel stimulus values resulted in slightly less systematic responding. Potential explanations for this pattern of results are discussed.

  16. Abnormal functional lateralization and activity of language brain areas in typical specific language impairment (developmental dysphasia)

    Science.gov (United States)

    De Guibert, Clément; Maumet, Camille; Jannin, Pierre; Ferré, Jean-Christophe; Tréguier, Catherine; Barillot, Christian; Le Rumeur, Elisabeth; Allaire, Catherine; Biraben, Arnaud

    2011-01-01

    Atypical functional lateralization and specialization for language have been proposed to account for developmental language disorders, yet results from functional neuroimaging studies are sparse and inconsistent. This functional magnetic resonance imaging study compared children with a specific subtype of specific language impairment affecting structural language (n=21), to a matched group of typically-developing children using a panel of four language tasks neither requiring reading nor metalinguistic skills, including two auditory lexico-semantic tasks (category fluency and responsive naming) and two visual phonological tasks based on picture naming. Data processing involved normalizing the data with respect to a matched pairs pediatric template, groups and between-groups analysis, and laterality indexes assessment within regions of interest using single and combined task analysis. Children with specific language impairment exhibited a significant lack of left lateralization in all core language regions (inferior frontal gyrus-opercularis, inferior frontal gyrus-triangularis, supramarginal gyrus, superior temporal gyrus), across single or combined task analysis, but no difference of lateralization for the rest of the brain. Between-group comparisons revealed a left hypoactivation of Wernicke’s area at the posterior superior temporal/supramarginal junction during the responsive naming task, and a right hyperactivation encompassing the anterior insula with adjacent inferior frontal gyrus and the head of the caudate nucleus during the first phonological task. This study thus provides evidence that this specific subtype of specific language impairment is associated with atypical lateralization and functioning of core language areas. PMID:21719430

  17. Functional magnetic resonance imaging: lateralization and localization of language in healthy volunteers

    International Nuclear Information System (INIS)

    Brinkhoff, C.

    2000-08-01

    Purpose: The purpose of this study was to determine the localization and hemispheric dominance of language in 21 right-handed and 21 left-handed healthy volunteers by functional magnetic resonance imaging (fMRI). Method: For language stimulation two tasks were used: phonological word generation, where subjects were asked to generate words starting with a given input letter (s, t, k), and a language perception and comprehension task requiring subjects to listen closely to the paragraph recall section of the Rivermead Behavioral Memory Test (RBMT) (1). In both tasks, 3 periods of activation were alternated with 3 rest periods of equal length. Activation were measured simultaneously in 15 horizontal slices using echoplanar imaging on a 1.5 T magnetic resonance scanner. Activated pixels were counted and anatomical localization was determined by using the Talairach Atlas of the brain (2). The pixel count in defined regions of the cortex in each hemisphere was taken as indicating the degree of language activation and was correlated with three conventional neuropsychological lateralization tasks: handedness was determined by Edinburgh Handedness Questionnaire (EHI) (3), manual dexterity was assessed by a pegboard test measuring the time to place all pegs for the right and left hand separately. A well-standardized dichotic listening paradigm using paired presentations of CV syllables was employed (4) in a non-forced condition to assess the (right or left ear) advantage indicating left or right hemisphere speech dominance. Results: Activation patterns differed significantly in both paradigms. Language comprehension caused maximum responses in temporal regions of both hemispheres, especially in the superior and the middle temporal gyrus. Independent from handedness, the language perception and comprehension paradigm exhibited bilateral activation predominantly. 52.4 % of right-handed subjects showed a bilateral activation pattern, whereas 33.3 % showed fMRI changes

  18. Altered organization of face processing networks in temporal lobe epilepsy

    Science.gov (United States)

    Riley, Jeffrey D.; Fling, Brett W.; Cramer, Steven C.; Lin, Jack J.

    2015-01-01

    SUMMARY Objective Deficits in social cognition are common and significant in people with temporal lobe epilepsy (TLE), but the functional and structural underpinnings remain unclear. The present study investigated how the side of seizure focus impacts face processing networks in temporal lobe epilepsy. Methods We used functional magnetic resonance imaging (fMRI) of a face processing paradigm to identify face responsive regions in 24 individuals with unilateral temporal lobe epilepsy (Left = 15; Right = 9) and 19 healthy controls. fMRI signals of face responsive regions ispilateral and contralateral to the side of seizure onset were delineated in TLE and compared to the healthy controls with right and left side combined. Diffusion tensor images were acquired to investigate structural connectivity between face regions that differed in fMRI signals between the two groups. Results In temporal lobe epilepsy, activation of the cortical face processing networks varied according to side of seizure onset. In temporal lobe epilepsy, the laterality of amygdala activation was shifted to the side contralateral to the seizure focus while controls showed no significant asymmetry. Furthermore, compared to controls, patients with TLE showed decreased activation of the occipital face responsive region in the ipsilateral side and an increased activity of the anterior temporal lobe in the contralateral side to the seizure focus. Probabilistic tractography revealed that the occipital face area and anterior temporal lobe are connected via the inferior longitudinal fasciculus, which in individuals with temporal lobe epilepsy showed reduced integrity. Significance Taken together, these findings suggest that brain function and white matter integrity of networks subserving face processing are impaired on the side of seizure onset, accompanied by altered responses on the side contralateral to the seizure. PMID:25823855

  19. Lateralization of Resting State Networks and Relationship to Age and Gender

    Science.gov (United States)

    Agcaoglu, O.; Miller, R.; Mayer, A.R.; Hugdahl, K.; Calhoun, V.D.

    2014-01-01

    Brain lateralization is a widely studied topic, however there has been little work focused on lateralization of intrinsic networks (regions showing similar patterns of covariation among voxels) in the resting brain. In this study, we evaluate resting state network lateralization in an age and gender-balanced functional magnetic resonance imaging (fMRI) dataset comprising over 600 healthy subjects ranging in age from 12 to 71. After establishing sample-wide network lateralization properties, we continue with an investigation of age and gender effects on network lateralization. All data was gathered on the same scanner and preprocessed using an automated pipeline (Scott et al., 2011). Networks were extracted via group independent component analysis (gICA) (Calhoun, Adali, Pearlson, & Pekar, 2001). Twenty-eight resting state networks discussed in previous (Allen et al., 2011) work were re-analyzed with a focus on lateralization. We calculated homotopic voxelwise measures of laterality in addition to a global lateralization measure, called the laterality cofactor, for each network. As expected, many of the intrinsic brain networks were lateralized. For example, the visual network was strongly right lateralized, auditory network and default mode networks were mostly left lateralized. Attentional and frontal networks included nodes that were left lateralized and other nodes that were right lateralized. Age was strongly related to lateralization in multiple regions including sensorimotor network regions precentral gyrus, postcentral gyrus and supramarginal gyrus; and visual network regions lingual gyrus; attentional network regions inferior parietal lobule, superior parietal lobule and middle temporal gyrus; and frontal network regions including the inferior frontal gyrus. Gender showed significant effects mainly in two regions, including visual and frontal networks. For example, the inferior frontal gyrus was more right lateralized in males. Significant effects of age

  20. Lateralization of resting state networks and relationship to age and gender.

    Science.gov (United States)

    Agcaoglu, O; Miller, R; Mayer, A R; Hugdahl, K; Calhoun, V D

    2015-01-01

    Brain lateralization is a widely studied topic, however there has been little work focused on lateralization of intrinsic networks (regions showing similar patterns of covariation among voxels) in the resting brain. In this study, we evaluate resting state network lateralization in an age and gender-balanced functional magnetic resonance imaging (fMRI) dataset comprising over 600 healthy subjects ranging in age from 12 to 71. After establishing sample-wide network lateralization properties, we continue with an investigation of age and gender effects on network lateralization. All data was gathered on the same scanner and preprocessed using an automated pipeline (Scott et al., 2011). Networks were extracted via group independent component analysis (gICA) (Calhoun et al., 2001). Twenty-eight resting state networks discussed in previous (Allen et al., 2011) work were re-analyzed with a focus on lateralization. We calculated homotopic voxelwise measures of laterality in addition to a global lateralization measure, called the laterality cofactor, for each network. As expected, many of the intrinsic brain networks were lateralized. For example, the visual network was strongly right lateralized, auditory network and default mode networks were mostly left lateralized. Attentional and frontal networks included nodes that were left lateralized and other nodes that were right lateralized. Age was strongly related to lateralization in multiple regions including sensorimotor network regions precentral gyrus, postcentral gyrus and supramarginal gyrus; and visual network regions lingual gyrus; attentional network regions inferior parietal lobule, superior parietal lobule and middle temporal gyrus; and frontal network regions including the inferior frontal gyrus. Gender showed significant effects mainly in two regions, including visual and frontal networks. For example, the inferior frontal gyrus was more right lateralized in males. Significant effects of age were found in

  1. Osteoradionecrosis of the temporal bone

    International Nuclear Information System (INIS)

    Fujimori, Masato; Koyama, Yukiko; Enomoto, Fuyuki; Ichikawa, Ginichiro

    2002-01-01

    We report a case of temporal bone necrosis that emerged after radiotherapy for epipharyngeal carcinoma performed 13 years ago. The patient was a 51-year-old male. His major complaint was left facial swelling. The patient underwent chemotherapy and radiotherapy (Co 60, 6120 rad), as the treatment of that period, for epipharyngeal carcinoma from September 30, 1986 to January 31, 1987. He also underwent lobectomy of the left temporal lobe in brain surgery for left temporal lobe necrosis in August, 1989. After that operation, we saw constriction in his left external acoustic meatus and continued the follow-up. On October 22, 1999 he felt a left facial swelling. We found skin defects and ulcer formation in the front part of his left ear. Although we administered an antiseptic and antibiotic to the diseased area, his condition did not improve. He was hospitalized for the purpose of undergoing medical treatment on January 6, 2000. We found extensive skin necrosis and defects in his left auricular area. The corrupted temporal bone reached the zygomatic, the bone department external acoustic meatus and the mastoid process was exposing. We performed debridement of the diseased area on January 19, 2000. On February 23, we performed reconstruction by left trapezius muscle flap after debridement once again. One year after the operation, the flap was completely incorporated. (author)

  2. Osteoradionecrosis of the temporal bone

    Energy Technology Data Exchange (ETDEWEB)

    Fujimori, Masato; Koyama, Yukiko; Enomoto, Fuyuki; Ichikawa, Ginichiro [Juntendo Univ., Tokyo (Japan). School of Medicine

    2002-08-01

    We report a case of temporal bone necrosis that emerged after radiotherapy for epipharyngeal carcinoma performed 13 years ago. The patient was a 51-year-old male. His major complaint was left facial swelling. The patient underwent chemotherapy and radiotherapy (Co 60, 6120 rad), as the treatment of that period, for epipharyngeal carcinoma from September 30, 1986 to January 31, 1987. He also underwent lobectomy of the left temporal lobe in brain surgery for left temporal lobe necrosis in August, 1989. After that operation, we saw constriction in his left external acoustic meatus and continued the follow-up. On October 22, 1999 he felt a left facial swelling. We found skin defects and ulcer formation in the front part of his left ear. Although we administered an antiseptic and antibiotic to the diseased area, his condition did not improve. He was hospitalized for the purpose of undergoing medical treatment on January 6, 2000. We found extensive skin necrosis and defects in his left auricular area. The corrupted temporal bone reached the zygomatic, the bone department external acoustic meatus and the mastoid process was exposing. We performed debridement of the diseased area on January 19, 2000. On February 23, we performed reconstruction by left trapezius muscle flap after debridement once again. One year after the operation, the flap was completely incorporated. (author)

  3. It takes two-skilled recognition of objects engages lateral areas in both hemispheres.

    Directory of Open Access Journals (Sweden)

    Merim Bilalić

    Full Text Available Our object recognition abilities, a direct product of our experience with objects, are fine-tuned to perfection. Left temporal and lateral areas along the dorsal, action related stream, as well as left infero-temporal areas along the ventral, object related stream are engaged in object recognition. Here we show that expertise modulates the activity of dorsal areas in the recognition of man-made objects with clearly specified functions. Expert chess players were faster than chess novices in identifying chess objects and their functional relations. Experts' advantage was domain-specific as there were no differences between groups in a control task featuring geometrical shapes. The pattern of eye movements supported the notion that experts' extensive knowledge about domain objects and their functions enabled superior recognition even when experts were not directly fixating the objects of interest. Functional magnetic resonance imaging (fMRI related exclusively the areas along the dorsal stream to chess specific object recognition. Besides the commonly involved left temporal and parietal lateral brain areas, we found that only in experts homologous areas on the right hemisphere were also engaged in chess specific object recognition. Based on these results, we discuss whether skilled object recognition does not only involve a more efficient version of the processes found in non-skilled recognition, but also qualitatively different cognitive processes which engage additional brain areas.

  4. Temporal Dissociation of Neocortical and Hippocampal Contributions to Mental Time Travel Using Intracranial Recordings in Humans.

    Science.gov (United States)

    Schurr, Roey; Nitzan, Mor; Eliahou, Ruth; Spinelli, Laurent; Seeck, Margitta; Blanke, Olaf; Arzy, Shahar

    2018-01-01

    In mental time travel (MTT) one is "traveling" back-and-forth in time, remembering, and imagining events. Despite intensive research regarding memory processes in the hippocampus, it was only recently shown that the hippocampus plays an essential role in encoding the temporal order of events remembered, and therefore plays an important role in MTT. Does it also encode the temporal relations of these events to the remembering self? We asked patients undergoing pre-surgical evaluation with depth electrodes penetrating the temporal lobes bilaterally toward the hippocampus to project themselves in time to a past, future, or present time-point, and then make judgments regarding various events. Classification analysis of intracranial evoked potentials revealed clear temporal dissociation in the left hemisphere between lateral-temporal electrodes, activated at ~100-300 ms, and hippocampal electrodes, activated at ~400-600 ms. This dissociation may suggest a division of labor in the temporal lobe during self-projection in time, hinting toward the different roles of the lateral-temporal cortex and the hippocampus in MTT and the temporal organization of the related events with respect to the experiencing self.

  5. Temporal Dissociation of Neocortical and Hippocampal Contributions to Mental Time Travel Using Intracranial Recordings in Humans

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    Roey Schurr

    2018-02-01

    Full Text Available In mental time travel (MTT one is “traveling” back-and-forth in time, remembering, and imagining events. Despite intensive research regarding memory processes in the hippocampus, it was only recently shown that the hippocampus plays an essential role in encoding the temporal order of events remembered, and therefore plays an important role in MTT. Does it also encode the temporal relations of these events to the remembering self? We asked patients undergoing pre-surgical evaluation with depth electrodes penetrating the temporal lobes bilaterally toward the hippocampus to project themselves in time to a past, future, or present time-point, and then make judgments regarding various events. Classification analysis of intracranial evoked potentials revealed clear temporal dissociation in the left hemisphere between lateral-temporal electrodes, activated at ~100–300 ms, and hippocampal electrodes, activated at ~400–600 ms. This dissociation may suggest a division of labor in the temporal lobe during self-projection in time, hinting toward the different roles of the lateral-temporal cortex and the hippocampus in MTT and the temporal organization of the related events with respect to the experiencing self.

  6. Vitiligo Lateral Lower Lip

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    Sahoo Antaryami

    2002-01-01

    Full Text Available Vitiligo characteristically affecting the lateral lower lip (LLL is a common presentation in South Orissa. This type of lesion has rarely been described in literature. One hundred eighteen such cases were studied during the period from October 1999 to September, 2000. LLL vitiligo constituted 16.39% of all vitiligo patients. Both sexes were affected equally. The peak age of onset was in the 2nd decade, mean duration of illness 21.46 months. Fifty six patients had unilateral lesion (38 on the left and 18 on the right. Among the 62 patients having bilateral lesions, the onset was more frequent on the left (38 than either the right (8 or both sides together (16. All the patients were right handed. Association with local factors like infection, trauma, cheilitis, FDE etc were associated in 38.98% of cases, but systemic or autoimmune diseases were not associated. Positive family history was found in 22% of cases.

  7. Language, gesture, and handedness: Evidence for independent lateralized networks.

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    Häberling, Isabelle S; Corballis, Paul M; Corballis, Michael C

    2016-09-01

    Language, gesture, and handedness are in most people represented in the left cerebral hemisphere. To explore the relations among these attributes, we collected fMRI images in a large sample of left- and right-handers while they performed language tasks and watched action sequences. Regions of interest included the frontal and parietal areas previously identified as comprising an action-observation network, and the frontal and temporal areas comprising the primary areas for language production and comprehension. All of the language areas and most of the action-observation areas showed an overall left-hemispheric bias, despite the participation of equal numbers of left- and right-handers. A factor analysis of the laterality indices derived from the different areas during the tasks indicated three independent networks, one associated with language, one associated with handedness, and one representing action observation independent of handedness. Areas 44 and 45, which together make up Broca's area, were part of the language and action-observation networks, but were not included in the part of the action observation network that was related to handedness, which in turn was strongly linked to areas in the parietal lobe. These results suggest an evolutionary scenario in which the primate mirror neuron system (MNS) became increasingly lateralized, and later fissioned onto subsystems with one mediating language and the other mediating the execution and observation of manual actions. The second network is further subdivided into one dependent on hand preference and one that is not, providing new insight into the tripartite system of language, handedness, and praxis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Cerebro-cerebellar interactions underlying temporal information processing.

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    Aso, Kenji; Hanakawa, Takashi; Aso, Toshihiko; Fukuyama, Hidenao

    2010-12-01

    The neural basis of temporal information processing remains unclear, but it is proposed that the cerebellum plays an important role through its internal clock or feed-forward computation functions. In this study, fMRI was used to investigate the brain networks engaged in perceptual and motor aspects of subsecond temporal processing without accompanying coprocessing of spatial information. Direct comparison between perceptual and motor aspects of time processing was made with a categorical-design analysis. The right lateral cerebellum (lobule VI) was active during a time discrimination task, whereas the left cerebellar lobule VI was activated during a timed movement generation task. These findings were consistent with the idea that the cerebellum contributed to subsecond time processing in both perceptual and motor aspects. The feed-forward computational theory of the cerebellum predicted increased cerebro-cerebellar interactions during time information processing. In fact, a psychophysiological interaction analysis identified the supplementary motor and dorsal premotor areas, which had a significant functional connectivity with the right cerebellar region during a time discrimination task and with the left lateral cerebellum during a timed movement generation task. The involvement of cerebro-cerebellar interactions may provide supportive evidence that temporal information processing relies on the simulation of timing information through feed-forward computation in the cerebellum.

  9. Dynamic spatial organization of the occipito-temporal word form area for second language processing.

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    Gao, Yue; Sun, Yafeng; Lu, Chunming; Ding, Guosheng; Guo, Taomei; Malins, Jeffrey G; Booth, James R; Peng, Danling; Liu, Li

    2017-08-01

    Despite the left occipito-temporal region having shown consistent activation in visual word form processing across numerous studies in different languages, the mechanisms by which word forms of second languages are processed in this region remain unclear. To examine this more closely, 16 Chinese-English and 14 English-Chinese late bilinguals were recruited to perform lexical decision tasks to visually presented words in both their native and second languages (L1 and L2) during functional magnetic resonance imaging scanning. Here we demonstrate that visual word form processing for L1 versus L2 engaged different spatial areas of the left occipito-temporal region. Namely, the spatial organization of the visual word form processing in the left occipito-temporal region is more medial and posterior for L2 than L1 processing in Chinese-English bilinguals, whereas activation is more lateral and anterior for L2 in English-Chinese bilinguals. In addition, for Chinese-English bilinguals, more lateral recruitment of the occipito-temporal region was correlated with higher L2 proficiency, suggesting higher L2 proficiency is associated with greater involvement of L1-preferred mechanisms. For English-Chinese bilinguals, higher L2 proficiency was correlated with more lateral and anterior activation of the occipito-temporal region, suggesting higher L2 proficiency is associated with greater involvement of L2-preferred mechanisms. Taken together, our results indicate that L1 and L2 recruit spatially different areas of the occipito-temporal region in visual word processing when the two scripts belong to different writing systems, and that the spatial organization of this region for L2 visual word processing is dynamically modulated by L2 proficiency. Specifically, proficiency in L2 in Chinese-English is associated with assimilation to the native language mechanisms, whereas L2 in English-Chinese is associated with accommodation to second language mechanisms. Copyright © 2017

  10. Dyslexic children lack word selectivity gradients in occipito-temporal and inferior frontal cortex

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    O.A. Olulade

    2015-01-01

    Full Text Available fMRI studies using a region-of-interest approach have revealed that the ventral portion of the left occipito-temporal cortex, which is specialized for orthographic processing of visually presented words (and includes the so-called “visual word form area”, VWFA, is characterized by a posterior-to-anterior gradient of increasing selectivity for words in typically reading adults, adolescents, and children (e.g. Brem et al., 2006, 2009. Similarly, the left inferior frontal cortex (IFC has been shown to exhibit a medial-to-lateral gradient of print selectivity in typically reading adults (Vinckier et al., 2007. Functional brain imaging studies of dyslexia have reported relative underactivity in left hemisphere occipito-temporal and inferior frontal regions using whole-brain analyses during word processing tasks. Hence, the question arises whether gradient sensitivities in these regions are altered in dyslexia. Indeed, a region-of-interest analysis revealed the gradient-specific functional specialization in the occipito-temporal cortex to be disrupted in dyslexic children (van der Mark et al., 2009. Building on these studies, we here (1 investigate if a word-selective gradient exists in the inferior frontal cortex in addition to the occipito-temporal cortex in normally reading children, (2 compare typically reading with dyslexic children, and (3 examine functional connections between these regions in both groups. We replicated the previously reported anterior-to-posterior gradient of increasing selectivity for words in the left occipito-temporal cortex in typically reading children, and its absence in the dyslexic children. Our novel finding is the detection of a pattern of increasing selectivity for words along the medial-to-lateral axis of the left inferior frontal cortex in typically reading children and evidence of functional connectivity between the most lateral aspect of this area and the anterior aspects of the occipito-temporal cortex. We

  11. Apraxia in left-handers.

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    Goldenberg, Georg

    2013-08-01

    In typical right-handed patients both apraxia and aphasia are caused by damage to the left hemisphere, which also controls the dominant right hand. In left-handed subjects the lateralities of language and of control of the dominant hand can dissociate. This permits disentangling the association of apraxia with aphasia from that with handedness. Pantomime of tool use, actual tool use and imitation of meaningless hand and finger postures were examined in 50 consecutive left-handed subjects with unilateral hemisphere lesions. There were three aphasic patients with pervasive apraxia caused by left-sided lesions. As the dominant hand is controlled by the right hemisphere, they constitute dissociations of apraxia from handedness. Conversely there were also three patients with pervasive apraxia caused by right brain lesions without aphasia. They constitute dissociations of apraxia from aphasia. Across the whole group of patients dissociations from handedness and from aphasia were observed for all manifestations of apraxia, but their frequency depended on the type of apraxia. Defective pantomime and defective tool use occurred rarely without aphasia, whereas defective imitation of hand, but not finger, postures was more frequent after right than left brain damage. The higher incidence of defective imitation of hand postures in right brain damage was mainly due to patients who had also hemi-neglect. This interaction alerts to the possibility that the association of right hemisphere damage with apraxia has to do with spatial aptitudes of the right hemisphere rather than with its control of the dominant left hand. Comparison with data from right-handed patients showed no differences between the severity of apraxia for imitation of hand or finger postures, but impairment on pantomime of tool use was milder in apraxic left-handers than in apraxic right-handers. This alleviation of the severity of apraxia corresponded with a similar alleviation of the severity of aphasia as

  12. Executive Semantic Processing Is Underpinned by a Large-scale Neural Network: Revealing the Contribution of Left Prefrontal, Posterior Temporal, and Parietal Cortex to Controlled Retrieval and Selection Using TMS

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    Whitney, Carin; Kirk, Marie; O'Sullivan, Jamie; Ralph, Matthew A. Lambon; Jefferies, Elizabeth

    2012-01-01

    To understand the meanings of words and objects, we need to have knowledge about these items themselves plus executive mechanisms that compute and manipulate semantic information in a task-appropriate way. The neural basis for semantic control remains controversial. Neuroimaging studies have focused on the role of the left inferior frontal gyrus…

  13. Laterality of radiographic osteoarthritis of the knee.

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    Komatsu, Daigo; Ikeuchi, Kazuma; Kojima, Toshihisa; Takegami, Yasuhiko; Amano, Takafumi; Tsuboi, Masaki; Ishiguro, Naoki; Hasegawa, Yukiharu

    2017-05-01

    There are few reports of the laterality in radiological knee osteoarthritis (ROA). This study aimed to evaluate laterality in terms of the minimum joint space width (mJSW) and osteophyte areas (OFs) in a cross-sectorial general population screen and elucidate the association between laterality and risk of osteoarthritis. We enrolled 330 participants (mean age 64.6 years) and examined the presence of ROA (Kellgren-Lawrence grade ≧ 2) laterality in terms of the mJSW and OF on the medial tibia using auto-measuring software. Moreover, we examined the association between laterality and leg dominance. The right and left medial mJSWs were 4.02 ± 0.98 mm and 4.05 ± 1.01 mm, respectively, showing no laterality; the laterals were also similar. The participants who had osteophytes ≥1 mm 2 in the right, left, and bilateral knees were 15, 37, and 57 respectively, with osteophytes being significantly more common in the left knee. The OF was significantly larger in the left knee. Conversely, the medial and lateral mJSWs and OF did not differ according to leg dominance. The prevalence of ROA was higher and the OF was more pronounced in the left knee. However, the mJSW showed no laterality. Additionally, the mJSW and OF showed no differences according to leg dominance.

  14. Unmasking Language Lateralization in Human Brain Intrinsic Activity

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    McAvoy, Mark; Mitra, Anish; Coalson, Rebecca S.; d'Avossa, Giovanni; Keidel, James L.; Petersen, Steven E.; Raichle, Marcus E.

    2016-01-01

    Lateralization of function is a fundamental feature of the human brain as exemplified by the left hemisphere dominance of language. Despite the prominence of lateralization in the lesion, split-brain and task-based fMRI literature, surprisingly little asymmetry has been revealed in the increasingly popular functional imaging studies of spontaneous fluctuations in the fMRI BOLD signal (so-called resting-state fMRI). Here, we show the global signal, an often discarded component of the BOLD signal in resting-state studies, reveals a leftward asymmetry that maps onto regions preferential for semantic processing in left frontal and temporal cortex and the right cerebellum and a rightward asymmetry that maps onto putative attention-related regions in right frontal, temporoparietal, and parietal cortex. Hemispheric asymmetries in the global signal resulted from amplitude modulation of the spontaneous fluctuations. To confirm these findings obtained from normal, healthy, right-handed subjects in the resting-state, we had them perform 2 semantic processing tasks: synonym and numerical magnitude judgment and sentence comprehension. In addition to establishing a new technique for studying lateralization through functional imaging of the resting-state, our findings shed new light on the physiology of the global brain signal. PMID:25636911

  15. Relations between neuropsychological findings and lateral asymmetries of cerebral blood flow measured by SPECT in dementia of Alzheimer type

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    Yoshimura, Nahoko; Soma, Yoshiaki; Ootsuki, Mika [Takeda General Hospital, Aizu-Wakamatsu, Fukushima (Japan)

    1993-10-01

    We studied 16 right-handed patients clinically diagnosed as dementia of Alzheimer type (6 men, 10 women; aged 63-85, mean 72.8 years). The average duration of symptoms was 2.7 years. Dementia ranged from mild to moderately severe. None had clinical or laboratory evidence of cerebrovascular disease (Hachinski ischemic scores for all patients were 4 or below 4). All received the Wechsler Adult Intelligence Scale (WAIS), Mini-mental State Test (MMS) and Western Aphasia Battery (WAB, First Japanese edition, 1986). Regional cerebral blood flow (rCBF) was evaluated by single photon emission CT (SPECT) with {sup 123}I-N-isopropyl-p-iodoamphetamine ({sup 123}I-IMP), using the Matsuda`s quantitative method. Regional tracer uptake was measured in regions of interests (ROIs) over right and left frontal, temporal, parietal and occipital cortical regions; basal ganglia; and cerebellar hemispheres. The subjects were divided into three groups on the basis of lateral asymmetries in the temporal and parietal cortexes of rCBF (leftleft, n=3; left=right, n=8). We decided that lateral asymmetry was present when rCBF for each ROI between left and right sides differs by more than 10%. General score (MMS, T-IQ) was not correlated with asymmetry of cerebral blood flow. Verbal IQ in patients with predominant hypoperfusion of left temporal and parietal lobe was significantly lower than other group, while performance IQ and WAB constructive scores were lower in those with right hemispheric hypoperfusion (p<0.05). We concluded that cerebral blood flow asymmetry by SPECT was related significantly to the deficit of language and constructive function in patients with dementia of Alzheimer type. Decreased rCBF in the left temporoparietal lobe was associated with language dysfunction, and that in the right hemisphere, with constructive dysfunction. (author).

  16. Relations between neuropsychological findings and lateral asymmetries of cerebral blood flow measured by SPECT in dementia of Alzheimer type

    International Nuclear Information System (INIS)

    Yoshimura, Nahoko; Soma, Yoshiaki; Ootsuki, Mika

    1993-01-01

    We studied 16 right-handed patients clinically diagnosed as dementia of Alzheimer type (6 men, 10 women; aged 63-85, mean 72.8 years). The average duration of symptoms was 2.7 years. Dementia ranged from mild to moderately severe. None had clinical or laboratory evidence of cerebrovascular disease (Hachinski ischemic scores for all patients were 4 or below 4). All received the Wechsler Adult Intelligence Scale (WAIS), Mini-mental State Test (MMS) and Western Aphasia Battery (WAB, First Japanese edition, 1986). Regional cerebral blood flow (rCBF) was evaluated by single photon emission CT (SPECT) with 123 I-N-isopropyl-p-iodoamphetamine ( 123 I-IMP), using the Matsuda's quantitative method. Regional tracer uptake was measured in regions of interests (ROIs) over right and left frontal, temporal, parietal and occipital cortical regions; basal ganglia; and cerebellar hemispheres. The subjects were divided into three groups on the basis of lateral asymmetries in the temporal and parietal cortexes of rCBF (left< right, n=5; right< left, n=3; left=right, n=8). We decided that lateral asymmetry was present when rCBF for each ROI between left and right sides differs by more than 10%. General score (MMS, T-IQ) was not correlated with asymmetry of cerebral blood flow. Verbal IQ in patients with predominant hypoperfusion of left temporal and parietal lobe was significantly lower than other group, while performance IQ and WAB constructive scores were lower in those with right hemispheric hypoperfusion (p<0.05). We concluded that cerebral blood flow asymmetry by SPECT was related significantly to the deficit of language and constructive function in patients with dementia of Alzheimer type. Decreased rCBF in the left temporoparietal lobe was associated with language dysfunction, and that in the right hemisphere, with constructive dysfunction. (author)

  17. The cortical signature of amyotrophic lateral sclerosis.

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    Federica Agosta

    Full Text Available The aim of this study was to explore the pattern of regional cortical thickness in patients with non-familial amyotrophic lateral sclerosis (ALS and to investigate whether cortical thinning is associated with disease progression rate. Cortical thickness analysis was performed in 44 ALS patients and 26 healthy controls. Group differences in cortical thickness and the age-by-group effects were assessed using vertex-by-vertex and multivariate linear models. The discriminatory ability of MRI variables in distinguishing patients from controls was estimated using the Concordance Statistics (C-statistic within logistic regression analyses. Correlations between cortical thickness measures and disease progression rate were tested using the Pearson coefficient. Relative to controls, ALS patients showed a bilateral cortical thinning of the primary motor, prefrontal and ventral frontal cortices, cingulate gyrus, insula, superior and inferior temporal and parietal regions, and medial and lateral occipital areas. There was a significant age-by-group effect in the sensorimotor cortices bilaterally, suggesting a stronger association between age and cortical thinning in ALS patients compared to controls. The mean cortical thickness of the sensorimotor cortices distinguished patients with ALS from controls (C-statistic ≥ 0.74. Cortical thinning of the left sensorimotor cortices was related to a faster clinical progression (r = -0.33, p = 0.03. Cortical thickness measurements allowed the detection and quantification of motor and extramotor involvement in patients with ALS. Cortical thinning of the precentral gyrus might offer a marker of upper motor neuron involvement and disease progression.

  18. The cortical signature of amyotrophic lateral sclerosis.

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    Agosta, Federica; Valsasina, Paola; Riva, Nilo; Copetti, Massimiliano; Messina, Maria Josè; Prelle, Alessandro; Comi, Giancarlo; Filippi, Massimo

    2012-01-01

    The aim of this study was to explore the pattern of regional cortical thickness in patients with non-familial amyotrophic lateral sclerosis (ALS) and to investigate whether cortical thinning is associated with disease progression rate. Cortical thickness analysis was performed in 44 ALS patients and 26 healthy controls. Group differences in cortical thickness and the age-by-group effects were assessed using vertex-by-vertex and multivariate linear models. The discriminatory ability of MRI variables in distinguishing patients from controls was estimated using the Concordance Statistics (C-statistic) within logistic regression analyses. Correlations between cortical thickness measures and disease progression rate were tested using the Pearson coefficient. Relative to controls, ALS patients showed a bilateral cortical thinning of the primary motor, prefrontal and ventral frontal cortices, cingulate gyrus, insula, superior and inferior temporal and parietal regions, and medial and lateral occipital areas. There was a significant age-by-group effect in the sensorimotor cortices bilaterally, suggesting a stronger association between age and cortical thinning in ALS patients compared to controls. The mean cortical thickness of the sensorimotor cortices distinguished patients with ALS from controls (C-statistic ≥ 0.74). Cortical thinning of the left sensorimotor cortices was related to a faster clinical progression (r = -0.33, p = 0.03). Cortical thickness measurements allowed the detection and quantification of motor and extramotor involvement in patients with ALS. Cortical thinning of the precentral gyrus might offer a marker of upper motor neuron involvement and disease progression.

  19. 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.)

  20. Metabolic changes of cerebrum by repetitive transcranial magnetic stimulation over lateral cerebellum: a study with FDG PET.

    Science.gov (United States)

    Cho, Sang Soo; Yoon, Eun Jin; Bang, Sung Ae; Park, Hyun Soo; Kim, Yu Kyeong; Strafella, Antonio P; Kim, Sang Eun

    2012-09-01

    To better understand the functional role of cerebellum within the large-scale cerebellocerebral neural network, we investigated the changes of neuronal activity elicited by cerebellar repetitive transcranial magnetic stimulation (rTMS) using (18)F-fluorodeoxyglucose (FDG) and positron emission tomography (PET). Twelve right-handed healthy volunteers were studied with brain FDG PET under two conditions: active rTMS of 1 Hz frequency over the left lateral cerebellum and sham stimulation. Compared to the sham condition, active rTMS induced decreased glucose metabolism in the stimulated left lateral cerebellum, the areas known to be involved in voluntary motor movement (supplementary motor area and posterior parietal cortex) in the right cerebral hemisphere, and the areas known to be involved in cognition and emotion (orbitofrontal, medial frontal, and anterior cingulate gyri) in the left cerebral hemisphere. Increased metabolism was found in cognition- and language-related brain regions such as the left inferior frontal gyrus including Broca's area, bilateral superior temporal gyri including Wernicke's area, and bilateral middle temporal gyri. Left cerebellar rTMS also led to increased metabolism in the left cerebellar dentate nucleus and pons. These results demonstrate that rTMS over the left lateral cerebellum modulates not only the target region excitability but also excitability of remote, but interconnected, motor-, language-, cognition-, and emotion-related cerebral regions. They provide further evidence that the cerebellum is involved not only in motor-related functions but also in higher cognitive abilities and emotion through the large-scale cerebellocereberal neural network.

  1. Laterality of basic auditory perception.

    Science.gov (United States)

    Sininger, Yvonne S; Bhatara, Anjali

    2012-01-01

    Laterality (left-right ear differences) of auditory processing was assessed using basic auditory skills: (1) gap detection, (2) frequency discrimination, and (3) intensity discrimination. Stimuli included tones (500, 1000, and 4000 Hz) and wide-band noise presented monaurally to each ear of typical adult listeners. The hypothesis tested was that processing of tonal stimuli would be enhanced by left ear (LE) stimulation and noise by right ear (RE) presentations. To investigate the limits of laterality by (1) spectral width, a narrow-band noise (NBN) of 450-Hz bandwidth was evaluated using intensity discrimination, and (2) stimulus duration, 200, 500, and 1000 ms duration tones were evaluated using frequency discrimination. A left ear advantage (LEA) was demonstrated with tonal stimuli in all experiments, but an expected REA for noise stimuli was not found. The NBN stimulus demonstrated no LEA and was characterised as a noise. No change in laterality was found with changes in stimulus durations. The LEA for tonal stimuli is felt to be due to more direct connections between the left ear and the right auditory cortex, which has been shown to be primary for spectral analysis and tonal processing. The lack of a REA for noise stimuli is unexplained. Sex differences in laterality for noise stimuli were noted but were not statistically significant. This study did establish a subtle but clear pattern of LEA for processing of tonal stimuli.

  2. Assessing signal-driven mechanism in neonates: brain responses to temporally and spectrally different sounds

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    Yasuyo eMinagawa-Kawai

    2011-06-01

    Full Text Available Past studies have found that in adults that acoustic properties of sound signals (such as fast vs. slow temporal features differentially activate the left and right hemispheres, and some have hypothesized that left-lateralization for speech processing may follow from left-lateralization to rapidly changing signals. Here, we tested whether newborns’ brains show some evidence of signal-specific lateralization responses using near-infrared spectroscopy (NIRS and auditory stimuli that elicits lateralized responses in adults, composed of segments that vary in duration and spectral diversity. We found significantly greater bilateral responses of oxygenated hemoglobin (oxy-Hb in the temporal areas for stimuli with a minimum segment duration of 21 ms, than stimuli with a minimum segment duration of 667 ms. However, we found no evidence for hemispheric asymmetries dependent on the stimulus characteristics. We hypothesize that acoustic-based functional brain asymmetries may develop throughout early infancy, and discuss their possible relationship with brain asymmetries for language.

  3. Specialization of the left supramarginal gyrus for hand-independent praxis representation is not related to hand dominance

    Science.gov (United States)

    Króliczak, Gregory; Piper, Brian J.; Frey, Scott H.

    2016-01-01

    Data from focal brain injury and functional neuroimaging studies implicate a distributed network of parieto-fronto-temporal areas in the human left cerebral hemisphere as playing distinct roles in the representation of meaningful actions (praxis). Because these data come primarily from right-handed individuals, the relationship between left cerebral specialization for praxis representation and hand dominance remains unclear. We used functional magnetic resonance imaging (fMRI) to evaluate the hypothesis that strongly left-handed (right hemisphere motor dominant) adults also exhibit this left cerebral specialization. Participants planned familiar actions for subsequent performance with the left or right hand in response to transitive (e.g., “pounding”) or intransitive (e.g. “waving”) action words. In linguistic control trials, cues denoted non-physical actions (e.g., “believing”). Action planning was associated with significant, exclusively left-lateralized and extensive increases of activity in the supramarginal gyrus (SMg), and more focal modulations in the left caudal middle temporal gyrus (cMTg). This activity was hand- and gesture-independent, i.e., unaffected by the hand involved in subsequent action performance, and the type of gesture (i.e., transitive or intransitive). Compared directly with right-handers, left-handers exhibited greater involvement of the right angular gyrus (ANg) and dorsal premotor cortex (dPMC), which is indicative of a less asymmetric functional architecture for praxis representation. We therefore conclude that the organization of mechanisms involved in planning familiar actions is influenced by one’s motor dominance. However, independent of hand dominance, the left SMg and cMTg are specialized for ideomotor transformations—the integration of conceptual knowledge and motor representations into meaningful actions. These findings support the view that higher-order praxis representation and lower-level motor dominance rely

  4. Evaluation of left ventricular function by cardiac CT

    International Nuclear Information System (INIS)

    Naito, Hiroaki; Kozuka, Takahiro

    1982-01-01

    Left ventricular function was evaluated by CT, which was compared with the data of left ventriculography for various cardiac diseases. The end diastolic volume of the left ventricle can be readily computed from CT, with a satisfactory correlation with that of left ventriculography (r = 0.95). The left ventricular ejection fraction, calculated from the areal ratio of the left ventricular lumen in end-diastolic imaging to that in end-sytolic imaging, also roughly reflects left ventricular contractile function, but shows correlation with left ventriculography by only r = 0.79. Although the cardiac output is not sensitive for functional evaluation, it can be directly calculated by means of dynamic scanning and shows a satisfactory correlation with the ear piece pigment dilution (r = 0.85). Evaluation of left ventricular function by CT shows a high precision in comparison with left ventriculography, but still lacks temporal resolving power. (Chiba, N.)

  5. Neural dynamics of morphological processing in spoken word comprehension: Laterality and automaticity

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    Caroline M. Whiting

    2013-11-01

    Full Text Available Rapid and automatic processing of grammatical complexity is argued to take place during speech comprehension, engaging a left-lateralised fronto-temporal language network. Here we address how neural activity in these regions is modulated by the grammatical properties of spoken words. We used combined magneto- and electroencephalography (MEG, EEG to delineate the spatiotemporal patterns of activity that support the recognition of morphologically complex words in English with inflectional (-s and derivational (-er affixes (e.g. bakes, baker. The mismatch negativity (MMN, an index of linguistic memory traces elicited in a passive listening paradigm, was used to examine the neural dynamics elicited by morphologically complex words. Results revealed an initial peak 130-180 ms after the deviation point with a major source in left superior temporal cortex. The localisation of this early activation showed a sensitivity to two grammatical properties of the stimuli: 1 the presence of morphological complexity, with affixed words showing increased left-laterality compared to non-affixed words; and 2 the grammatical category, with affixed verbs showing greater left-lateralisation in inferior frontal gyrus compared to affixed nouns (bakes vs. beaks. This automatic brain response was additionally sensitive to semantic coherence (the meaning of the stem vs. the meaning of the whole form in fronto-temporal regions. These results demonstrate that the spatiotemporal pattern of neural activity in spoken word processing is modulated by the presence of morphological structure, predominantly engaging the left-hemisphere’s fronto-temporal language network, and does not require focused attention on the linguistic input.

  6. A Rare Case of Craniopharyngioma in the Temporal Lobe

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    Sasan Razmjoo

    2017-01-01

    Full Text Available Herein, we report on a rare case of craniopharyngioma arising in the left temporal lobe with no prior history of head trauma or surgery. There was a solid-cystic mass in the left temporal lobe on MR images. To the best of our knowledge, this is the second case of a craniopharyngioma occurring in the temporal lobe.

  7. Voxel-based morphometry (VBM) based assessment of gray matter loss in medial temporal lobe epilepsy; comparison with FDG PET

    International Nuclear Information System (INIS)

    Kang, Hye Jin; Lee, Ho Young; Lee, Jae Sung; Kang, Eun Joo; Lee, Sang Gun; Chang, Kee Hyun; Lee, Dong Soo

    2004-01-01

    The aims of this study were to find brain regions in which gray matter volume was reduced and to show the capability of voxel-based morphometry (VBM) analysis for lateralizing epileptogenic zones in medial temporal lobe epilepsy (mTLE). The findings were compared with fluorodeoxyglucose positron emission tomography (FDG PET). MR T1-weighted images of 12 left mTLE and 11 right mTLE patients were compared with those of 37 normal controls. Images were transformed to standard MNI space and averaged in order to create study-specific brain template. Each image was normalized to this local template and brain tissues were segmented. Modulation VBM analysis was performed in order to observe gray matter volume change. Gray matter was smoothed with a Gaussian kernel. After these preprocessing, statistical analysis was performed using statistical parametric mapping software (SPM99). FDG PET images were compared with those of 22 normal controls using SPM. Gray matter volume was significantly reduced in the left amygdala and hippocampus in left mTLE. In addition, volume of cerebellum, anterior cingulate, and fusiform gyrus in both sides and left insula was reduced. In right mTLE, volume was reduced significantly in right hippocampus. In contrast, FDG uptake was decreased in broad areas of left or right temporal lobes in left TLE and right TLE, respectively. Gray matter loss was found in the ipsilateral hippocampus by modulation VBM analysis in medial temporal lobe epilepsy. This VBM analysis might be useful in lateralizing the epileptogenic zones in medial temporal lobe epilepsy, while SPM analysis of FDG PET disclosed hypometabolic epileptogenic zones

  8. Voxel-based morphometry (VBM) based assessment of gray matter loss in medial temporal lobe epilepsy; comparison with FDG PET

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hye Jin; Lee, Ho Young; Lee, Jae Sung; Kang, Eun Joo; Lee, Sang Gun; Chang, Kee Hyun; Lee, Dong Soo [College of Medicine, Seoul National Univ., Seoul (Korea, Republic of)

    2004-02-01

    The aims of this study were to find brain regions in which gray matter volume was reduced and to show the capability of voxel-based morphometry (VBM) analysis for lateralizing epileptogenic zones in medial temporal lobe epilepsy (mTLE). The findings were compared with fluorodeoxyglucose positron emission tomography (FDG PET). MR T1-weighted images of 12 left mTLE and 11 right mTLE patients were compared with those of 37 normal controls. Images were transformed to standard MNI space and averaged in order to create study-specific brain template. Each image was normalized to this local template and brain tissues were segmented. Modulation VBM analysis was performed in order to observe gray matter volume change. Gray matter was smoothed with a Gaussian kernel. After these preprocessing, statistical analysis was performed using statistical parametric mapping software (SPM99). FDG PET images were compared with those of 22 normal controls using SPM. Gray matter volume was significantly reduced in the left amygdala and hippocampus in left mTLE. In addition, volume of cerebellum, anterior cingulate, and fusiform gyrus in both sides and left insula was reduced. In right mTLE, volume was reduced significantly in right hippocampus. In contrast, FDG uptake was decreased in broad areas of left or right temporal lobes in left TLE and right TLE, respectively. Gray matter loss was found in the ipsilateral hippocampus by modulation VBM analysis in medial temporal lobe epilepsy. This VBM analysis might be useful in lateralizing the epileptogenic zones in medial temporal lobe epilepsy, while SPM analysis of FDG PET disclosed hypometabolic epileptogenic zones.

  9. Diagnosing Dyslexia: The Screening of Auditory Laterality.

    Science.gov (United States)

    Johansen, Kjeld

    A study investigated whether a correlation exists between the degree and nature of left-brain laterality and specific reading and spelling difficulties. Subjects, 50 normal readers and 50 reading disabled persons native to the island of Bornholm, had their auditory laterality screened using pure-tone audiometry and dichotic listening. Results…

  10. Altered functional connectivity differs in stroke survivors with impaired touch sensation following left and right hemisphere lesions

    Directory of Open Access Journals (Sweden)

    Peter Goodin

    Full Text Available One in two survivors experience impairment in touch sensation after stroke. The nature of this impairment is likely associated with changes associated with the functional somatosensory network of the brain; however few studies have examined this. In particular, the impact of lesioned hemisphere has not been investigated. We examined resting state functional connectivity in 28 stroke survivors, 14 with left hemisphere and 14 with right hemisphere lesion, and 14 healthy controls. Contra-lesional hands showed significantly decreased touch discrimination. Whole brain functional connectivity (FC data was extracted from four seed regions, i.e. primary (S1 and secondary (S2 somatosensory cortices in both hemispheres. Whole brain FC maps and Laterality Indices (LI were calculated for subgroups. Inter-hemispheric FC was greater in healthy controls compared to the combined stroke cohort from the left S1 seed and bilateral S2 seeds. The left lesion subgroup showed decreased FC, relative to controls, from left ipsi-lesional S1 to contra-lesional S1 and to distributed temporal, occipital and parietal regions. In comparison, the right lesion group showed decreased connectivity from contra-lesional left S1 and bilateral S2 to ipsi-lesional parietal operculum (S2, and to occipital and temporal regions. The right lesion group also showed increased intra-hemispheric FC from ipsi-lesional right S1 to inferior parietal regions compared to controls. In comparison to the left lesion group, those with right lesion showed greater intra-hemispheric connectivity from left S1 to left parietal and occipital regions and from right S1 to right angular and parietal regions. Laterality Indices were significantly greater for stroke subgroups relative to matched controls for contra-lesional S1 (left lesion group and contra-lesional S2 (both groups. We provide evidence of altered functional connectivity within the somatosensory network, across both hemispheres, and to other

  11. Effect of low frequency rTMS stimulation over lateral cerebellum: a FDG PET study

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Eun Jin; Cho, Sang Soo; Bang, Soong Ae; Park, Hyun Soo; Kim, Sang Eun [Seoul National Univ. College of Medicine, Seoul (Korea, Republic of)

    2007-07-01

    Several lines of evidence suggested the involvement of cerebellum in cognitive function as well as motor function. Because of the measurement difficulty of functional connectivity, little is known about the underlying mechanism involvement of cerebellum in motor and cognitive function in living human brain. To understand the role of cerebellum within the neural network, we investigated the changes of neuronal activity elicited by the cerebellar repetitive transcranial magnetic stimulation (rTMS). 11 right-handed normal volunteers (age: 23.4{+-}2.5 y;6 males) were studied with FDG PET under two conditions; sham and 1Hz rTMS over left lateral cerebellum. With 10 min inter-block interval, three blocks of rTMS were started with the intravenous injection of [18F]FDG. In each block, 5min rTMS were delivered with an intensity of 90% of the resting motor threshold (RMT). Sham rTMS was delivered with same protocol but the coil was positioned perpendicular to the target area with 50% RMT. PET scans were acquired immediately after the rTMS stimulation. Sham and 1Hz rTMS images compared using paired t-test with SPM2. Inhibited neuronal activity compare to the sham condition were revealed in the stimulated left lateral cerebellum and orbitofrontal gyrus and right motor related areas (S1, SMA and posterior parietal cortex). While enhanced neuronal activity compare to the sham condition were revealed in the bilateral inferior frontal gyri including Broca's area and superior temporal gyrus including primary auditory cortex. Bilateral middle temporal, left precentral and right middle occipital gyri were also showed enhanced neuronal activity. This result showed that rTMS over left lateral cerebellum modulate direct vicinity of the targeted region and a large network of remote interconnected contralateral motor and ipsilateral language related brain regions. Present result provide evidence that cerebellum may contribute to language related cognitive function as well as motor

  12. Effect of low frequency rTMS stimulation over lateral cerebellum: a FDG PET study

    International Nuclear Information System (INIS)

    Yoon, Eun Jin; Cho, Sang Soo; Bang, Soong Ae; Park, Hyun Soo; Kim, Sang Eun

    2007-01-01

    Several lines of evidence suggested the involvement of cerebellum in cognitive function as well as motor function. Because of the measurement difficulty of functional connectivity, little is known about the underlying mechanism involvement of cerebellum in motor and cognitive function in living human brain. To understand the role of cerebellum within the neural network, we investigated the changes of neuronal activity elicited by the cerebellar repetitive transcranial magnetic stimulation (rTMS). 11 right-handed normal volunteers (age: 23.4±2.5 y;6 males) were studied with FDG PET under two conditions; sham and 1Hz rTMS over left lateral cerebellum. With 10 min inter-block interval, three blocks of rTMS were started with the intravenous injection of [18F]FDG. In each block, 5min rTMS were delivered with an intensity of 90% of the resting motor threshold (RMT). Sham rTMS was delivered with same protocol but the coil was positioned perpendicular to the target area with 50% RMT. PET scans were acquired immediately after the rTMS stimulation. Sham and 1Hz rTMS images compared using paired t-test with SPM2. Inhibited neuronal activity compare to the sham condition were revealed in the stimulated left lateral cerebellum and orbitofrontal gyrus and right motor related areas (S1, SMA and posterior parietal cortex). While enhanced neuronal activity compare to the sham condition were revealed in the bilateral inferior frontal gyri including Broca's area and superior temporal gyrus including primary auditory cortex. Bilateral middle temporal, left precentral and right middle occipital gyri were also showed enhanced neuronal activity. This result showed that rTMS over left lateral cerebellum modulate direct vicinity of the targeted region and a large network of remote interconnected contralateral motor and ipsilateral language related brain regions. Present result provide evidence that cerebellum may contribute to language related cognitive function as well as motor control

  13. Auditory temporal processing in patients with temporal lobe epilepsy.

    Science.gov (United States)

    Lavasani, Azam Navaei; Mohammadkhani, Ghassem; Motamedi, Mahmoud; Karimi, Leyla Jalilvand; Jalaei, Shohreh; Shojaei, Fereshteh Sadat; Danesh, Ali; Azimi, Hadi

    2016-07-01

    Auditory temporal processing is the main feature of speech processing ability. Patients with temporal lobe epilepsy, despite their normal hearing sensitivity, may present speech recognition disorders. The present study was carried out to evaluate the auditory temporal processing in patients with unilateral TLE. The present study was carried out on 25 patients with epilepsy: 11 patients with right temporal lobe epilepsy and 14 with left temporal lobe epilepsy with a mean age of 31.1years and 18 control participants with a mean age of 29.4years. The two experimental and control groups were evaluated via gap-in-noise and duration pattern sequence tests. One-way ANOVA was run to analyze the data. The mean of the threshold of the GIN test in the control group was observed to be better than that in participants with LTLE and RTLE. Also, it was observed that the percentage of correct responses on the DPS test in the control group and in participants with RTLE was better than that in participants with LTLE. Patients with TLE have difficulties in temporal processing. Difficulties are more significant in patients with LTLE, likely because the left temporal lobe is specialized for the processing of temporal information. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Correlation between memory, proton magnetic resonance spectroscopy, and interictal epileptiform discharges in temporal lobe epilepsy related to mesial temporal sclerosis.

    Science.gov (United States)

    Mantoan, Marcele Araújo Silva; Caboclo, Luís Otávio Sales Ferreira; de Figueiredo Ferreira Guilhoto, Laura Maria; Lin, Katia; da Silva Noffs, Maria Helena; de Souza Silva Tudesco, Ivanda; Belzunces, Erich; Carrete, Henrique; Bussoletti, Renato Tavares; Centeno, Ricardo Silva; Sakamoto, Américo Ceiki; Yacubian, Elza Márcia Targas

    2009-11-01

    The aim of the study described here was to examine the relationship between memory function, proton magnetic resonance spectroscopy ((1)H-MRS) abnormalities, and interictal epileptiform discharge (IED) lateralization in patients with temporal lobe epilepsy (TLE) related to unilateral mesial temporal sclerosis. We assessed performance on tests of memory function and intelligence quotient (IQ) in 29 right-handed outpatients and 24 controls. IEDs were assessed on 30-minute-awake and 30-minute-sleep EEG samples. Patients had (1)H-MRS at 1.5 T. There was a negative correlation between IQ (P=0.031) and Rey Auditory Verbal Learning Test results (P=0.022) and epilepsy duration; between(1)H-MRS findings and epilepsy duration (P=0.027); and between N-acetylaspartate (NAA) levels and IEDs (P=0.006) in contralateral mesial temporal structures in the left MTS group. (1)H-MRS findings, IEDs, and verbal function were correlated. These findings suggest that IEDs and NAA/(Cho+Cr) ratios reflecting neural metabolism are closely related to verbal memory function in mesial temporal sclerosis. Higher interictal activity on the EEG was associated with a decline in total NAA in contralateral mesial temporal structures.

  15. The association between hemispheric specialization for language production and for spatial attention depends on left-hand preference strength.

    Science.gov (United States)

    Zago, Laure; Petit, Laurent; Mellet, Emmanuel; Jobard, Gaël; Crivello, Fabrice; Joliot, Marc; Mazoyer, Bernard; Tzourio-Mazoyer, Nathalie

    2016-12-01

    Cerebral lateralization for language production and spatial attention and their relationships with manual preference strength (MPS) were assessed in a sample of 293 healthy volunteers, including 151 left-handers, using fMRI during covert sentence production (PROD) and line bisection judgment (LBJ) tasks, as compared to high- and low-level reference tasks. At the group level, we found the expected complementary hemispheric specialization (HS) with leftward asymmetries for PROD within frontal and temporal regions and rightward asymmetries for LBJ within frontal and posterior occipito-parieto-temporal regions. Individual hemispheric (HLI) and regional (frontal and occipital) lateralization indices (LI) were then calculated on the activation maps for PROD and LBJ. We found a correlation between the degree of rightward cerebral asymmetry and the leftward behavioral attentional bias recorded during LBJ task. This correlation was found when LBJ-LI was computed over the hemispheres, in the frontal lobes, but not in the occipital lobes. We then investigated whether language production and spatial attention cerebral lateralization relate to each other, and whether manual preference was a variable that impacted the complementary HS of these functions. No correlation was found between spatial and language LIs in the majority of our sample of participants, including right-handers with a strong right-hand preference (sRH, n=97) and mixed-handers (MH, n=97), indicating that these functions lateralized independently. By contrast, in the group of left-handers with a strong left-hand preference (sLH, n= 99), a negative correlation was found between language and spatial lateralization. This negative correlation was found when LBJ-LI and PROD-LI were computed over the hemispheres, in the frontal lobes and between the occipital lobes for LBJ and the frontal lobes for PROD. These findings underline the importance to include sLH in the study sample to reveal the underlying mechanisms of

  16. Exposing asymmetric gray matter vulnerability in amyotrophic lateral sclerosis

    Directory of Open Access Journals (Sweden)

    Matthew S. Devine

    2015-01-01

    Full Text Available Limb weakness in amyotrophic lateral sclerosis (ALS is typically asymmetric. Previous studies have identified an effect of limb dominance on onset and spread of weakness, however relative atrophy of dominant and non-dominant brain regions has not been investigated. Our objective was to use voxel-based morphometry (VBM to explore gray matter (GM asymmetry in ALS, in the context of limb dominance. 30 ALS subjects were matched with 17 healthy controls. All subjects were right-handed. Each underwent a structural MRI sequence, from which GM segmentations were generated. Patterns of GM atrophy were assessed in ALS subjects with first weakness in a right-sided limb (n = 15 or left-sided limb (n = 15. Within each group, a voxelwise comparison was also performed between native and mirror GM images, to identify regions of hemispheric GM asymmetry. Subjects with ALS showed disproportionate atrophy of the dominant (left motor cortex hand area, irrespective of the side of first limb weakness (p < 0.01. Asymmetric atrophy of the left somatosensory cortex and temporal gyri was only observed in ALS subjects with right-sided onset of limb weakness. Our VBM protocol, contrasting native and mirror images, was able to more sensitively detect asymmetric GM pathology in a small cohort, compared with standard methods. These findings indicate particular vulnerability of dominant upper limb representation in ALS, supporting previous clinical studies, and with implications for cortical organisation and selective vulnerability.

  17. Lateral step initiation behavior in older adults

    OpenAIRE

    Sparto, Patrick J; Jennings, J Richard; Furman, Joseph M; Redfern, Mark S

    2013-01-01

    Older adults have varied postural responses during induced and voluntary lateral stepping. The purpose of the research was to quantify the occurrence of different stepping strategies during lateral step initiation in older adults and to relate the stepping responses to retrospective history of falls. Seventy community-ambulating older adults (mean age 76 y, range 70–94 y) performed voluntary lateral steps as quickly as possible to the right or left in response to a visual cue, in a blocked de...

  18. [Brain lateralization and seizure semiology: ictal clinical lateralizing signs].

    Science.gov (United States)

    Horváth, Réka; Kalmár, Zsuzsanna; Fehér, Nóra; Fogarasi, András; Gyimesi, Csilla; Janszky, József

    2008-07-30

    Clinical lateralizing signs are the phenomena which can unequivocally refer to the hemispheric onset of epileptic seizures. They can improve the localization of epileptogenic zone during presurgical evaluation, moreover, their presence can predict a success of surgical treatment. Primary sensory phenomena such as visual aura in one half of the field of vision or unilateral ictal somatosensory sensation always appear on the contralateral to the focus. Periictal unilateral headache, although it is an infrequent symptom, is usually an ipsilateral sign. Primary motor phenomena like epileptic clonic, tonic movements, the version of head ubiquitously appear contralateral to the epileptogenic zone. Very useful lateralization sign is the ictal hand-dystonia which lateralizes to the contralateral hemisphere in nearly 100%. The last clonus of the secondarily generalized tonic-clonic seizure lateralizes to the ipsilateral hemisphere in 85%. The fast component of ictal nystagmus appears in nearly 100% on the contralateral side of the epileptic focus. Vegetative symptoms during seizures arising from temporal lobe such as spitting, nausea, vomiting, urinary urge are typical for seizures originating from non-dominant (right) hemisphere. Ictal pallor and cold shivers are dominant hemispheric lateralization signs. Postictal unilateral nose wiping refers to the ipsilateral hemispheric focus compared to the wiping hand. Ictal or postictal aphasia refers to seizure arising from dominant hemisphere. Intelligable speech during complex partial seizures appears in non-dominant seizures. Automatism with preserved consciousness refers to the seizures of non-dominant temporal lobe.

  19. Unique Neural Characteristics of Atypical Lateralization of Language in Healthy Individuals

    Directory of Open Access Journals (Sweden)

    Szymon P. Biduła

    2017-09-01

    Full Text Available Using functional magnetic resonance imaging (fMRI in 63 healthy participants, including left-handed and ambidextrous individuals, we tested how atypical lateralization of language—i. e., bilateral or right hemispheric language representation—differs from the typical left-hemisphere dominance. Although regardless of their handedness, all 11 participants from the atypical group engaged classical language centers, i.e., Broca's and Wernicke's areas, the right-hemisphere components of the default mode network (DMN, including the angular gyrus and middle temporal gyrus, were also critically involved during the verbal fluency task. Importantly, activity in these regions could not be explained in terms of mirroring the typical language pattern because left-hemisphere dominant individuals did not exhibit similar significant signal modulations. Moreover, when spatial extent of language-related activity across whole brain was considered, the bilateral language organization entailed more diffuse functional processing. Finally, we detected significant differences between the typical and atypical group in the resting-state connectivity at the global and local level. These findings suggest that the atypical lateralization of language has unique features, and is not a simple mirror image of the typical left hemispheric language representation.

  20. Determinants of brain metabolism changes in mesial temporal lobe epilepsy.

    Science.gov (United States)

    Chassoux, Francine; Artiges, Eric; Semah, Franck; Desarnaud, Serge; Laurent, Agathe; Landre, Elisabeth; Gervais, Philippe; Devaux, Bertrand; Helal, Ourkia Badia

    2016-06-01

    To determine the main factors influencing metabolic changes in mesial temporal lobe epilepsy (MTLE) due to hippocampal sclerosis (HS). We prospectively studied 114 patients with MTLE (62 female; 60 left HS; 15- to 56-year-olds) with (18) F-fluorodeoxyglucose-positron emission tomography and correlated the results with the side of HS, structural atrophy, electroclinical features, gender, age at onset, epilepsy duration, and seizure frequency. Imaging processing was performed using statistical parametric mapping. Ipsilateral hypometabolism involved temporal (mesial structures, pole, and lateral cortex) and extratemporal areas including the insula, frontal lobe, perisylvian regions, and thalamus, more extensively in right HS (RHS). A relative increase of metabolism (hypermetabolism) was found in the nonepileptic temporal lobe and in posterior areas bilaterally. Voxel-based morphometry detected unilateral hippocampus atrophy and gray matter concentration decrease in both frontal lobes, more extensively in left HS (LHS). Regardless of the structural alterations, the topography of hypometabolism correlated strongly with the extent of epileptic networks (mesial, anterior-mesiolateral, widespread mesiolateral, and bitemporal according to the ictal spread), which were larger in RHS. Notably, widespread perisylvian and bitemporal hypometabolism was found only in RHS. Mirror hypermetabolism was grossly proportional to the hypometabolic areas, coinciding partly with the default mode network. Gender-related effect was significant mainly in the contralateral frontal lobe, in which metabolism was higher in female patients. Epilepsy duration correlated with the contralateral temporal metabolism, positively in LHS and negatively in RHS. Opposite results were found with age at onset. High seizure frequency correlated negatively with the contralateral metabolism in LHS. Epileptic networks, as assessed by electroclinical correlations, appear to be the main determinant of

  1. Temporal lobe epilepsy: analysis of patients with dual pathology.

    Science.gov (United States)

    Salanova, V; Markand, O; Worth, R

    2004-02-01

    To determine the frequency and types of dual pathology in patients with temporal lobe epilepsy (TLE) and to analyze the clinical manifestations and surgical outcome. A total of 240 patients with TLE underwent temporal resections following a comprehensive pre-surgical evaluation. Thirty-seven (15.4%) of these had hippocampal sclerosis (HS) or temporal lobe gliosis in association with another lesion (dual pathology). Eighteen of 37 patients with dual pathology had heterotopia of the temporal lobe, nine had cortical dysplasia, four had cavernous angiomas or arteriovenous malformations, one had a dysembryoplastic neuroepithelial tumor, one had a contusion and four patients had cerebral infarctions in childhood. 68.5% had abnormal head magnetic resonance imagings, 91.3% had abnormal positron emission tomography scans, and 96% had abnormal ictal SPECT. The intracarotid amobarbital procedure (IAP) showed impaired memory of the epileptogenic side in 72% of the patients. Twenty patients had left and 17 had right-sided en bloc temporal resections, including the lesion and mesial temporal structures. Twenty-six (70.2%) became seizure-free, eight (21.6%) had rare seizures, two (5.4%) had worthwhile seizure reduction and one (2.7%) had no improvement (range of follow-up 1-16 years, mean = 7.4 years). 15.4% had dual pathology. The dual pathology was almost exclusively seen in patients whose lesions were congenital, or occurred early in life, suggesting that the hippocampus is more vulnerable and more readily develops HS in early childhood. Resections, including the lateral and mesial temporal structures led to a favorable outcome with no mortality and little morbidity.

  2. Aetiological factors in left-handedness

    Directory of Open Access Journals (Sweden)

    Milenković Sanja M.

    2005-01-01

    Full Text Available Lateralisation associates the extremities and senses of one side of the body, which are connected by afferent and efferent pathways, with the primary motor and sensory areas of the hemisphere on the opposite side. Dominant laterality denotes the appearance of a dominant extremity or sense in the performance of complex psychomotor activities. Laterality is manifested both as right-handedness or left-handedness, which are functionally equivalent and symmetrical in the performance of activities. Right-handedness is significantly more common than left-handedness. Genetic theory is most widely accepted in explaining the onset of lateralisation. According to this theory, the models of brain organisation asymmetry (anatomical, functional, and biochemical are strongly, genetically determined. However, the inability to clearly demonstrate the association between genetic factors and left-handedness has led researchers to investigate the effects of the environment on left-handedness. Of particular interest are the intrauterine environment and the factors influencing foetal development, of which hormones and ultrasound exposure are the most significant. It has been estimated that an extra five cases of nonright-handed lateralisation can be expected in every 100 males who were exposed to ultrasound in utero compared to those who were not. Socio-cultural pressure on left-handed individuals was much more severe in the past, which is confirmed by scientific findings that left-handedness is present in 13% of individuals in their twenties, while in less than 1% of individuals in their eighties.

  3. Motor laterality as an indicator of speech laterality.

    Science.gov (United States)

    Flowers, Kenneth A; Hudson, John M

    2013-03-01

    The determination of speech laterality, especially where it is anomalous, is both a theoretical issue and a practical problem for brain surgery. Handedness is commonly thought to be related to speech representation, but exactly how is not clearly understood. This investigation analyzed handedness by preference rating and performance on a reliable task of motor laterality in 34 patients undergoing a Wada test, to see if they could provide an indicator of speech laterality. Hand usage preference ratings divided patients into left, right, and mixed in preference. Between-hand differences in movement time on a pegboard task determined motor laterality. Results were correlated (χ2) with speech representation as determined by a standard Wada test. It was found that patients whose between-hand difference in speed on the motor task was small or inconsistent were the ones whose Wada test speech representation was likely to be ambiguous or anomalous, whereas all those with a consistently large between-hand difference showed clear unilateral speech representation in the hemisphere controlling the better hand (χ2 = 10.45, df = 1, p laterality are related where they both involve a central control of motor output sequencing and that a measure of that aspect of the former will indicate the likely representation of the latter. A between-hand measure of motor laterality based on such a measure may indicate the possibility of anomalous speech representation. PsycINFO Database Record (c) 2013 APA, all rights reserved.

  4. Associations between schizotypy and cerebral laterality.

    Science.gov (United States)

    Park, Haeme R P; Waldie, Karen E

    2017-03-01

    Atypical lateralization for language has been found in schizophrenia, suggesting that language and thought disorders on the schizophrenia spectrum may be due to left hemispheric dysfunction. However, research with those with non-clinical schizotypy has been inconsistent, with some studies finding reduced or reversed language laterality (particularly with positive schizotypal traits), and others finding typical left hemispheric specialization. The aim of the current study was to use both a behavioural (dual reading-finger tapping) task and an functional magnetic resonance imaging lexical decision task to investigate language laterality in a university sample of high- and low-schizotypal adults. Findings revealed no evidence for atypical lateralization in our sample for both overall schizotypy (measured by the Oxford-Liverpool Inventory of Feelings and Experiences) and positive schizotypy (measured by the Unusual Experiences subscale) groups. Our findings provide further evidence that non-clinical schizotypy is not associated with atypical language laterality.

  5. The right hemisphere's contribution to discourse processing: A study in temporal lobe epilepsy.

    Science.gov (United States)

    Lomlomdjian, Carolina; Múnera, Claudia P; Low, Daniel M; Terpiluk, Verónica; Solís, Patricia; Abusamra, Valeria; Kochen, Silvia

    2017-08-01

    Discourse skills - in which the right hemisphere has an important role - enables verbal communication by selecting contextually relevant information and integrating it coherently to infer the correct meaning. However, language research in epilepsy has focused on single word analysis related mainly to left hemisphere processing. The purpose of this study was to investigate discourse abilities in patients with right lateralized medial temporal lobe epilepsy (RTLE) by comparing their performance to that of patients with left temporal lobe epilepsy (LTLE). 74 pharmacoresistant temporal lobe epilepsy (TLE) patients were evaluated: 34 with RTLE and 40 with LTLE. Subjects underwent a battery of tests that measure comprehension and production of conversational and narrative discourse. Disease related variables and general neuropsychological data were evaluated. The RTLE group presented deficits in interictal conversational and narrative discourse, with a disintegrated speech, lack of categorization and misinterpretation of social meaning. LTLE group, on the other hand, showed a tendency to lower performance in logical-temporal sequencing. RTLE patients showed discourse deficits which have been described in right hemisphere damaged patients due to other etiologies. Medial and anterior temporal lobe structures appear to link semantic, world knowledge, and social cognition associated areas to construct a contextually related coherent meaning. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Evaluation of ictal brain SPET using statistical parametric mapping in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J.D.; Kim, H.-J.; Jeon, T.J.; Kim, M.J. [Div. of Nuclear Medicine, Yonsei University Medical College, Seoul (Korea); Lee, B.I.; Kim, O.J. [Dept. of Neurology, Yonsei University Medical College, Seoul (Korea)

    2000-11-01

    An automated voxel-based analysis of brain images using statistical parametric mapping (SPM) is accepted as a standard approach in the analysis of activation studies in positron emission tomography and functional magnetic resonance imaging. This study aimed to investigate whether or not SPM would increase the diagnostic yield of ictal brain single-photon emission tomography (SPET) in temporal lobe epilepsy (TLE). Twenty-one patients (age 27.14{+-}5.79 years) with temporal lobe epilepsy (right in 8, left in 13) who had a successful seizure outcome after surgery and nine normal subjects were included in the study. The data of ictal and interictal brain SPET of the patients and baseline SPET of the normal control group were analysed using SPM96 software. The t statistic SPM(t) was transformed to SPM(Z) with various thresholds of P<0.05, 0.005 and 0.001, and corrected extent threshold P value of 0.05. The SPM data were compared with the conventional ictal and interictal subtraction method. On group comparison, ictal SPET showed increased uptake within the epileptogenic mesial temporal lobe. On single case analysis, ictal SPET images correctly lateralized the epileptogenic temporal lobe in 18 cases, falsely lateralized it in one and failed to lateralize it in two as compared with the mean image of the normal group at a significance level of P<0.05. Comparing the individual ictal images with the corresponding interictal group, 15 patients were correctly lateralized, one was falsely lateralized and four were not lateralized. At significance levels of P<0.005 and P<0.001, correct lateralization of the epileptogenic temporal lobe was achieved in 15 and 13 patients, respectively, as compared with the normal group. On the other hand, when comparison was made with the corresponding interictal group, only 7 out of 21 patients were correctly lateralized at the threshold of P<0.005 and five at P<0.001. The result of the subtraction method was close to the single case analysis on

  7. Evaluation of ictal brain SPET using statistical parametric mapping in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Lee, J.D.; Kim, H.-J.; Jeon, T.J.; Kim, M.J.; Lee, B.I.; Kim, O.J.

    2000-01-01

    An automated voxel-based analysis of brain images using statistical parametric mapping (SPM) is accepted as a standard approach in the analysis of activation studies in positron emission tomography and functional magnetic resonance imaging. This study aimed to investigate whether or not SPM would increase the diagnostic yield of ictal brain single-photon emission tomography (SPET) in temporal lobe epilepsy (TLE). Twenty-one patients (age 27.14±5.79 years) with temporal lobe epilepsy (right in 8, left in 13) who had a successful seizure outcome after surgery and nine normal subjects were included in the study. The data of ictal and interictal brain SPET of the patients and baseline SPET of the normal control group were analysed using SPM96 software. The t statistic SPM(t) was transformed to SPM(Z) with various thresholds of P<0.05, 0.005 and 0.001, and corrected extent threshold P value of 0.05. The SPM data were compared with the conventional ictal and interictal subtraction method. On group comparison, ictal SPET showed increased uptake within the epileptogenic mesial temporal lobe. On single case analysis, ictal SPET images correctly lateralized the epileptogenic temporal lobe in 18 cases, falsely lateralized it in one and failed to lateralize it in two as compared with the mean image of the normal group at a significance level of P<0.05. Comparing the individual ictal images with the corresponding interictal group, 15 patients were correctly lateralized, one was falsely lateralized and four were not lateralized. At significance levels of P<0.005 and P<0.001, correct lateralization of the epileptogenic temporal lobe was achieved in 15 and 13 patients, respectively, as compared with the normal group. On the other hand, when comparison was made with the corresponding interictal group, only 7 out of 21 patients were correctly lateralized at the threshold of P<0.005 and five at P<0.001. The result of the subtraction method was close to the single case analysis on

  8. The course of language functions after temporal lobe epilepsy surgery: a prospective study.

    Science.gov (United States)

    Giovagnoli, A R; Parente, A; Didato, G; Manfredi, V; Deleo, F; Tringali, G; Villani, F

    2016-12-01

    Anterior temporal lobectomy (ATL) within the language-dominant hemisphere can impair naming. This prospective study examined the pre-operative to post-operative course of different language components, clarifying which changes are relevant within the short-term and long-term outcome of language. Patients with drug-resistant temporal lobe epilepsy (TLE) were evaluated using the Token, Boston Naming and Word Fluency tests assessing sentence comprehension and word-finding on visual, semantic or phonemic cues. A total of 106 patients were evaluated before and 6 months, 1 and 2 years after ATL; 60 patients were also evaluated after 5 years and 38 controls were assessed at baseline. Seizure outcome was comparable between the left and right TLE patients. Before surgery, naming and word fluency were impaired in the left and right TLE patients, whereas sentence comprehension was normal. After left or right ATL, word fluency progressively improved, naming showed early worsening and late improvement after left ATL and progressive improvement after right ATL, and sentence comprehension did not change. At the 5-year follow-up, naming improvement was clinically significant in 31% and 71% of the left and right TLE patients, respectively. Pre-operative naming, ATL laterality, schooling, and post-operative seizure frequency and number of antiepileptic drugs predicted post-operative naming. Pre-operative word fluency and schooling predicted post-operative word fluency. Left or right TLE can impair word-finding but not sentence comprehension. After ATL, word-finding may improve for a long time, depending on TLE laterality, seizure control and mental reserve. These findings may clarify prognosis prior to treatment. © 2016 EAN.

  9. Temporal networks

    CERN Document Server

    Saramäki, Jari

    2013-01-01

    The concept of temporal networks is an extension of complex networks as a modeling framework to include information on when interactions between nodes happen. Many studies of the last decade examine how the static network structure affect dynamic systems on the network. In this traditional approach  the temporal aspects are pre-encoded in the dynamic system model. Temporal-network methods, on the other hand, lift the temporal information from the level of system dynamics to the mathematical representation of the contact network itself. This framework becomes particularly useful for cases where there is a lot of structure and heterogeneity both in the timings of interaction events and the network topology. The advantage compared to common static network approaches is the ability to design more accurate models in order to explain and predict large-scale dynamic phenomena (such as, e.g., epidemic outbreaks and other spreading phenomena). On the other hand, temporal network methods are mathematically and concept...

  10. Fibrous Dysplasia of the Temporal Bone with External Auditory Canal Stenosis and Secondary Cholesteatoma.

    Science.gov (United States)

    Liu, Yu-Hsi; Chang, Kuo-Ping

    2016-04-01

    Fibrous dysplasia is a slowly progressive benign fibro-osseous disease, rarely occurring in temporal bones. In these cases, most bony lesions developed from the bony part of the external auditory canals, causing otalgia, hearing impairment, otorrhea, and ear hygiene blockade and probably leading to secondary cholesteatoma. We presented the medical history of a 24-year-old woman with temporal monostotic fibrous dysplasia with secondary cholesteatoma. The initial presentation was unilateral conductive hearing loss. A hard external canal tumor contributing to canal stenosis and a near-absent tympanic membrane were found. Canaloplasty and type I tympanoplasty were performed, but the symptoms recurred after 5 years. She received canal wall down tympanomastoidectomy with ossciculoplasty at the second time, and secondary cholesteatoma in the middle ear was diagnosed. Fifteen years later, left otorrhea recurred again and transcanal endoscopic surgery was performed for middle ear clearance. Currently, revision surgeries provide a stable auditory condition, but her monostotic temporal fibrous dysplasia is still in place.

  11. Upper motor neuron predominant degeneration with frontal and temporal lobe atrophy.

    Science.gov (United States)

    Konagaya, M; Sakai, M; Matsuoka, Y; Konagaya, Y; Hashizume, Y

    1998-11-01

    The autopsy findings of a 78-year-old man mimicking primary lateral sclerosis (PLS) are reported. He showed slowly progressive spasticity, pseudobulbar palsy and character change, and died 32 months after the onset of symptoms. Autopsy revealed severe atrophy of the frontal and temporal lobes, remarkable neuronal loss and gliosis in the precentral gyrus, left temporal lobe pole and amygdala, mild degeneration of the Ammon's horn, degeneration of the corticospinal tract, and very mild involvement of the lower motor neurons. The anterior horn cells only occasionally demonstrated Bunina body by cystatin-C staining, and skein-like inclusions by ubiquitin staining. This is a peculiar case with concomitant involvement in the motor cortex and temporal lobe in motor neuron disease predominantly affecting the upper motor neuron.

  12. Asynchronous ripple oscillations between left and right hippocampi during slow-wave sleep.

    Science.gov (United States)

    Villalobos, Claudio; Maldonado, Pedro E; Valdés, José L

    2017-01-01

    Spatial memory, among many other brain processes, shows hemispheric lateralization. Most of the published evidence suggests that the right hippocampus plays a leading role in the manipulation of spatial information. Concurrently in the hippocampus, memory consolidation during sleep periods is one of the key steps in the formation of newly acquired spatial memory traces. One of the most characteristic oscillatory patterns in the hippocampus are sharp-wave ripple (SWR) complexes. Within this complex, fast-field oscillations or ripples have been demonstrated to be instrumental in the memory consolidation process. Since these ripples are relevant for the consolidation of memory traces associated with spatial navigation, and this process appears to be lateralized, we hypothesize that ripple events between both hippocampi would exhibit different temporal dynamics. We tested this idea by using a modified "split-hyperdrive" that allows us to record simultaneous LFPs from both right and left hippocampi of Sprague-Dawley rats during sleep. We detected individual events and found that during sleep periods these ripples exhibited a different occurrence patterns between hemispheres. Most ripple events were synchronous between intra- rather than inter-hemispherical recordings, suggesting that ripples in the hippocampus are independently generated and locally propagated within a specific hemisphere. In this study, we propose the ripples' lack of synchrony between left and right hippocampi as the putative physiological mechanism underlying lateralization of spatial memory.

  13. Altered functional connectivity differs in stroke survivors with impaired touch sensation following left and right hemisphere lesions.

    Science.gov (United States)

    Goodin, Peter; Lamp, Gemma; Vidyasagar, Rishma; McArdle, David; Seitz, Rüdiger J; Carey, Leeanne M

    2018-01-01

    One in two survivors experience impairment in touch sensation after stroke. The nature of this impairment is likely associated with changes associated with the functional somatosensory network of the brain; however few studies have examined this. In particular, the impact of lesioned hemisphere has not been investigated. We examined resting state functional connectivity in 28 stroke survivors, 14 with left hemisphere and 14 with right hemisphere lesion, and 14 healthy controls. Contra-lesional hands showed significantly decreased touch discrimination. Whole brain functional connectivity (FC) data was extracted from four seed regions, i.e. primary (S1) and secondary (S2) somatosensory cortices in both hemispheres. Whole brain FC maps and Laterality Indices (LI) were calculated for subgroups. Inter-hemispheric FC was greater in healthy controls compared to the combined stroke cohort from the left S1 seed and bilateral S2 seeds. The left lesion subgroup showed decreased FC, relative to controls, from left ipsi-lesional S1 to contra-lesional S1 and to distributed temporal, occipital and parietal regions. In comparison, the right lesion group showed decreased connectivity from contra-lesional left S1 and bilateral S2 to ipsi-lesional parietal operculum (S2), and to occipital and temporal regions. The right lesion group also showed increased intra-hemispheric FC from ipsi-lesional right S1 to inferior parietal regions compared to controls. In comparison to the left lesion group, those with right lesion showed greater intra-hemispheric connectivity from left S1 to left parietal and occipital regions and from right S1 to right angular and parietal regions. Laterality Indices were significantly greater for stroke subgroups relative to matched controls for contra-lesional S1 (left lesion group) and contra-lesional S2 (both groups). We provide evidence of altered functional connectivity within the somatosensory network, across both hemispheres, and to other networks in stroke

  14. Gender-specific effects of emotional modulation on visual temporal order thresholds.

    Science.gov (United States)

    Liang, Wei; Zhang, Jiyuan; Bao, Yan

    2015-09-01

    Emotions affect temporal information processing in the low-frequency time window of a few seconds, but little is known about their effect in the high-frequency domain of some tens of milliseconds. The present study aims to investigate whether negative and positive emotional states influence the ability to discriminate the temporal order of visual stimuli, and whether gender plays a role in temporal processing. Due to the hemispheric lateralization of emotion, a hemispheric asymmetry between the left and the right visual field might be expected. Using a block design, subjects were primed with neutral, negative and positive emotional pictures before performing temporal order judgment tasks. Results showed that male subjects exhibited similarly reduced order thresholds under negative and positive emotional states, while female subjects demonstrated increased threshold under positive emotional state and reduced threshold under negative emotional state. Besides, emotions influenced female subjects more intensely than male subjects, and no hemispheric lateralization was observed. These observations indicate an influence of emotional states on temporal order processing of visual stimuli, and they suggest a gender difference, which is possibly associated with a different emotional stability.

  15. Balloon-occluded retrograde transvenous obliteration of gastric varix draining via the left inferior phrenic vein into the left hepatic vein

    International Nuclear Information System (INIS)

    Ibukuro, Kenji; Mori, Koichi; Tsukiyama, Toshitaka; Inoue, Yoshihiro; Iwamoto, Yukako; Tagawa, Kazumi

    1999-01-01

    We encountered a patient with gastric varix draining not via the usual left suprarenal vein but via the left inferior phrenic vein joining the left hepatic vein. Transfemoral balloon-occluded retrograde transvenous obliteration (BRTO) of the varix was performed under balloon occlusion of the left inferior phrenic vein via the left hepatic vein and retrograde injection of the sclerosing agent (5% of ethanolamine oleate) into the gastric varix. Disappearance of the gastric varix was confirmed on endoscopic examination 2 months later.

  16. Temporal pole signal abnormality on MR imaging in temporal lobe epilepsy with hippocampal sclerosis: a fluid-attenuated inversion-recovery study.

    Science.gov (United States)

    Carrete, Henrique; Abdala, Nitamar; Lin, Kátia; Caboclo, Luís Otávio; Centeno, Ricardo Silva; Sakamoto, Américo Ceiki; Szjenfeld, Jacob; Nogueira, Roberto Gomes; Yacubian, Elza Márcia Targas

    2007-09-01

    To determine the frequency and regional involvement of temporal pole signal abnormality (TPA) in patients with hippocampal sclerosis (HS) using fluid-attenuated inversion-recovery (FLAIR) MR imaging, and to correlate this feature with history. Coronal FLAIR images of the temporal pole were assessed in 120 patients with HS and in 30 normal subjects, to evaluate gray-white matter demarcation. Ninety (75%) of 120 patients had associated TPA. The HS side made difference regarding the presence of TPA, with a left side prevalence (p=0.04, chi2 test). The anteromedial zone of temporal pole was affected in 27 (30%) out of 90 patients. In 63 (70%) patients the lateral zone were also affected. Patients with TPA were younger at seizure onset (p=0.018), but without association with duration of epilepsy. Our FLAIR study show temporal pole signal abnormality in 3/4 of patients with HS, mainly seen on the anteromedial region, with a larger prevalence when the left hippocampus was involved.

  17. Temporal pole signal abnormality on MR imaging in temporal lobe epilepsy with hippocampal sclerosis: a fluid-attenuated inversion-recovery study

    International Nuclear Information System (INIS)

    Carrete Junior, Henrique; Abdala, Nitamar; Szjenfeld, Jacob; Nogueira, Roberto Gomes; Lin, Katia; Caboclo, Luis Otavio; Centeno, Ricardo Silva; Sakamoto, Americo Ceiki; Yacubian, Elza Marcia Targas

    2007-01-01

    Objective: To determine the frequency and regional involvement of temporal pole signal abnormality (TPA) in patients with hippocampal sclerosis (HS) using fluid-attenuated inversion-recovery (FLAIR) MR imaging, and to correlate this feature with history. Method: Coronal FLAIR images of the temporal pole were assessed in 120 patients with HS and in 30 normal subjects, to evaluate gray-white matter demarcation. Results: Ninety (75%) of 120 patients had associated TPA. The HS side made difference regarding the presence of TPA, with a left side prevalence (p=0.04, χ 2 test). The anteromedial zone of temporal pole was affected in 27 (30%) out of 90 patients. In 63 (70%) patients the lateral zone were also affected. Patients with TPA were younger at seizure onset (p=0.018), but without association with duration of epilepsy. Conclusion: Our FLAIR study show temporal pole signal abnormality in 3/4 of patients with HS, mainly seen on the anteromedial region, with a larger prevalence when the left hippocampus was involved. (author)

  18. Right anterior temporal lobe dysfunction underlies theory of mind impairments in semantic dementia.

    Science.gov (United States)

    Irish, Muireann; Hodges, John R; Piguet, Olivier

    2014-04-01

    Semantic dementia is a progressive neurodegenerative disorder characterized by the amodal and profound loss of semantic knowledge attributable to the degeneration of the left anterior temporal lobe. Although traditionally conceptualized as a language disorder, patients with semantic dementia display significant alterations in behaviour and socioemotional functioning. Recent evidence points to an impaired capacity for theory of mind in predominantly left-lateralized cases of semantic dementia; however, it remains unclear to what extent semantic impairments contribute to these deficits. Further the neuroanatomical signature of such disturbance remains unknown. Here, we sought to determine the neural correlates of theory of mind performance in patients with left predominant semantic dementia (n=11), in contrast with disease-matched cases with behavioural-variant frontotemporal dementia (n=10) and Alzheimer's disease (n=10), and healthy older individuals (n=14) as control participants. Participants completed a simple cartoons task, in which they were required to describe physical and theory of mind scenarios. Irrespective of subscale, patients with semantic dementia exhibited marked impairments relative to control subjects; however, only theory of mind deficits persisted when we covaried for semantic comprehension. Voxel-based morphometry analyses revealed that atrophy in right anterior temporal lobe structures, including the right temporal fusiform cortex, right inferior temporal gyrus, bilateral temporal poles and amygdalae, correlated significantly with theory of mind impairments in the semantic dementia group. Our results point to the marked disruption of cognitive functions beyond the language domain in semantic dementia, not exclusively attributable to semantic processing impairments. The significant involvement of right anterior temporal structures suggests that with disease evolution, the encroachment of pathology into the contralateral hemisphere heralds the

  19. Project Temporalities

    DEFF Research Database (Denmark)

    Tryggestad, Kjell; Justesen, Lise; Mouritsen, Jan

    2013-01-01

    Purpose – The purpose of this paper is to explore how animals can become stakeholders in interaction with project management technologies and what happens with project temporalities when new and surprising stakeholders become part of a project and a recognized matter of concern to be taken...... into account. Design/methodology/approach – The paper is based on a qualitative case study of a project in the building industry. The authors use actor-network theory (ANT) to analyze the emergence of animal stakeholders, stakes and temporalities. Findings – The study shows how project temporalities can...... multiply in interaction with project management technologies and how conventional linear conceptions of project time may be contested with the emergence of new non-human stakeholders and temporalities. Research limitations/implications – The study draws on ANT to show how animals can become stakeholders...

  20. Sex Differences in Cerebral Laterality of Language and Visuospatial Processing

    Science.gov (United States)

    Clements, A. M.; Rimrodt, S. L.; Abel, J. R.; Blankner, J. G.; Mostofsky, S. H.; Pekar, J. J.; Denckla, M. B.; Cutting, L. E.

    2006-01-01

    Sex differences on language and visuospatial tasks are of great interest, with differences in hemispheric laterality hypothesized to exist between males and females. Some functional imaging studies examining sex differences have shown that males are more left lateralized on language tasks and females are more right lateralized on visuospatial…

  1. Is performance better when brain functions are typically lateralized?

    NARCIS (Netherlands)

    Geuze, Reint; Zickert, Nele; Beking, Tess; Groothuis, Antonius

    2014-01-01

    Lateralization refers to the dominant involvement of one homologous region of the brain over the other in functional task performance. Direction and strength of lateralization depend on the functional task. It is well known that language is lateralized to the left hemisphere, even in most

  2. Improved proper name recall in aging after electrical stimulation of the anterior temporal lobes

    Directory of Open Access Journals (Sweden)

    Lars A Ross

    2011-10-01

    Full Text Available Evidence from neuroimaging and neuropsychology suggests that portions of the anterior temporal lobes play a critical role in proper name retrieval. We previously found that anodal transcranial direct current stimulation (tDCS to the anterior temporal lobes improved retrieval of proper names in young adult. Here we extend that finding to older adults who tend to experience greater proper-naming deficits than young adults. The task was to look at pictures of famous faces or landmarks and verbally recall the associated proper name. Our results show a numerical improvement in face naming after left or right anterior temporal lobe stimulation, but a statistically significant effect only after left-lateralized stimulation. The magnitude of the enhancing effect was similar in older and younger adults but the lateralization of the effect differed depending on age. These results provide evidence that tDCS may be a useful tool for the neurorehabilitation of cognitive function in healthy and pathological cognitive decline.

  3. Temporal-spatial characteristics of phase-amplitude coupling in electrocorticogram for human temporal lobe epilepsy.

    Science.gov (United States)

    Zhang, Ruihua; Ren, Ye; Liu, Chunyan; Xu, Na; Li, Xiaoli; Cong, Fengyu; Ristaniemi, Tapani; Wang, YuPing

    2017-09-01

    Neural activity of the epileptic human brain contains low- and high-frequency oscillations in different frequency bands, some of which have been used as reliable biomarkers of the epileptogenic brain areas. However, the relationship between the low- and high-frequency oscillations in different cortical areas during the period from pre-seizure to post-seizure has not been completely clarified. We recorded electrocorticogram data from the temporal lobe and hippocampus of seven patients with temporal lobe epilepsy. The modulation index based on the Kullback-Leibler distance and the phase-amplitude coupling co-modulogram were adopted to quantify the coupling strength between the phase of low-frequency oscillations (0.2-10Hz) and the amplitude of high-frequency oscillations (11-400Hz) in different seizure epochs. The time-varying phase-amplitude modulogram was used to analyze the phase-amplitude coupling pattern during the entire period from pre-seizure to post-seizure in both the left and right temporal lobe and hippocampus. Channels with strong modulation index were compared with the seizure onset channels identified by the neurosurgeons and the resection channels in the clinical surgery. The phase-amplitude coupling strength (modulation index) increased significantly in the mid-seizure epoch and decrease significantly in seizure termination and post-seizure epochs (ptemporal cortex and hippocampus. The "fall-max" phase-amplitude modulation pattern, i.e., high-frequency amplitudes were largest in the low-frequency phase range [-π, 0], which corresponded to the falling edges of low-frequency oscillations, appeared in the middle period of the seizures at epileptic focus channels. Channels with strong modulation index appeared on the corresponding left or right temporal cortex of surgical resection and overlapped with the clinical resection zones in all patients. The "fall-max" pattern between the phase of low-frequency oscillation and amplitude of high

  4. Left heart ventricular angiography

    Science.gov (United States)

    ... blood vessels. These x-ray pictures create a "movie" of the left ventricle as it contracts rhythmically. ... 22578925 www.ncbi.nlm.nih.gov/pubmed/22578925 . Review Date 9/26/2016 Updated by: Michael A. ...

  5. Left heart catheterization

    Science.gov (United States)

    Catheterization - left heart ... to help guide the catheters up into your heart and arteries. Dye (sometimes called "contrast") will be ... in the blood vessels that lead to your heart. The catheter is then moved through the aortic ...

  6. Decrease of NAA with aging outside the seizure focus in mesial temporal lobe epilepsy--a proton-MRS study at 3 Tesla.

    Science.gov (United States)

    Riederer, Franz; Bittsanský, Michal; Lehner-Baumgartner, Eva; Baumgartner, Christoph; Mlynárik, Vladimír; Gruber, Stephan; Moser, Ewald; Kaya, Marihan; Serles, Wolfgang

    2007-11-07

    There is evidence that chronic pharmacoresistant temporal lobe epilepsy (TLE) is a progressive disorder accompanied by mental deterioration. We investigated effects of aging on cerebral N-acetyl-aspartate (NAA) concentrations in the temporal lobe of 12 patients with pharmacoresistant mesial TLE (mTLE) and 22 healthy controls by means of proton-magnetic resonance spectroscopy ((1)H-MRS) at 3 T. Furthermore, we calculated correlations between NAA concentrations and measures of verbal and figural memory in patients. In mTLE patients but not in healthy controls the concentration of NAA in the lateral temporal lobe was negatively correlated with age. In patients with mTLE NAA in left lateral temporal voxels correlated with verbal memory. NAA in medial temporal voxels did not correlate with age or neuropsychological measures. Significant decrease of NAA with age in the lateral temporal lobe of patients with mTLE provides evidence for progressive neuronal dysfunction with aging. NAA is a marker of neuronal integrity since it correlates with verbal memory.

  7. Brain and behavioural lateralization in invertebrates.

    OpenAIRE

    Elisa eFrasnelli

    2013-01-01

    Traditionally, only humans were thought to exhibit brain and behavioural asymmetries, but several studies have revealed that most vertebrates are also lateralized. Recently, evidence of left-right asymmetries in invertebrates has begun to emerge, suggesting that lateralization of the nervous system may be a feature of simpler brains as well as more complex ones. Here I present some examples in invertebrates of sensory and motor asymmetries, as well as asymmetries in the nervous system. I illu...

  8. Longitudinal course of cortical thickness decline in amyotrophic lateral sclerosis.

    Science.gov (United States)

    Schuster, Christina; Kasper, Elisabeth; Machts, Judith; Bittner, Daniel; Kaufmann, Jörn; Benecke, Reiner; Teipel, Stefan; Vielhaber, Stefan; Prudlo, Johannes

    2014-10-01

    To determine longitudinal rates of cortical atrophy in classical Amyotrophic lateral sclerosis (ALS) and ALS variants. Rates of cortical thinning were determined between 2 scans, 3-15 months apart, in 77 ALS patients: 51 classical, 12 upper motor neuron (UMN), and 14 lower motor neuron (LMN) ALS variants. Cortical thickness at the first assessment was compared with 60 healthy controls matched by age and gender. Atrophy rates were compared between patient sub-groups and correlated with disease duration, progression, and severity. Using a cross-sectional analysis, we found a significant difference in cortical thickness between ALS patients and controls in the motor and extra-motor areas (left medial orbito frontal gyrus, left inferior parietal gyrus, bilateral insular cortex, right fusiform gyrus, bilateral precuneus). Using a longitudinal analysis, we found a significant decline of cortical thickness in frontal, temporal, and parietal regions over the course of the study in ALS patients. Effects were independent of the clinical subtype, with exception of the precentral gyrus (p gyrus, the UMN-dominant subjects exhibited intermediate rates of atrophy, and the classical ALS patients exhibited no such change. Atrophy of the precentral gyrus in classical ALS indicates a floor effect at the first assessment, resulting in a lack of further atrophy over time. Structural loss of the precentral gyrus appears to be an early sign of classical ALS. Over time, patterns of cortical thinning in extra-motor areas can be identified in ALS, regardless of the phenotype.

  9. Preoperative MR imaging-based volume measurements of the hippocampal formation and anterior temporal lobe in epileptic patients

    International Nuclear Information System (INIS)

    Jack, C.R.; Sharbrough, F.W.; Twomey, C.; Zinsmeister, A.R.; Cascino, G.D.; Hirschorn, K.A.; Marsh, W.R.

    1989-01-01

    MR-based volume measurements of the anterior temporal lobe and hippocampal formation were performed in 36 patients who subsequently underwent surgery for medically refractory temporal lobe epilepsy. Seizure lateralization was based on standard clinical and electroencephalographic criteria. No surgical pathologic specimens contained structural lesions; epilepsy in these patients was therefore presumably due to mesial sclerosis. The right-minus-left hippocampal formation volume difference was greater than 0 in all 20 patients operated on the left side and less than 0 in all 16 patients operated on the right side. This difference completely separated the two surgical groups, while the same measurement in a group of 35 normal controls fell between the two surgical groups. Measurements of the anterior temporal to be showed a similar trend but incompletely separated controls, right- and left-sided epileptics. These results suggest that in a significant percentage of cases, MR-based volume measurements correctly identify the unilateral hippocampal atrophy that is known to occur in cases of mesial temporal sclerosis

  10. Temporal summation of heat pain in humans: Evidence supporting thalamocortical modulation.

    Science.gov (United States)

    Tran, Tuan D; Wang, Heng; Tandon, Animesh; Hernandez-Garcia, Luis; Casey, Kenneth L

    2010-07-01

    Noxious cutaneous contact heat stimuli (48 degrees C) are perceived as increasingly painful when the stimulus duration is extended from 5 to 10s, reflecting the temporal summation of central neuronal activity mediating heat pain. However, the sensation of increasing heat pain disappears, reaching a plateau as stimulus duration increases from 10 to 20s. We used functional magnetic resonance imaging (fMRI) in 10 healthy subjects to determine if active central mechanisms could contribute to this psychophysical plateau. During heat pain durations ranging from 5 to 20s, activation intensities in the bilateral orbitofrontal cortices and the activation volume in the left primary (S1) somatosensory cortex correlated only with perceived stimulus intensity and not with stimulus duration. Activation volumes increased with both stimulus duration and perceived intensity in the left lateral thalamus, posterior insula, inferior parietal cortex, and hippocampus. In contrast, during the psychophysical plateau, both the intensity and volume of thalamic and cortical activations in the right medial thalamus, right posterior insula, and left secondary (S2) somatosensory cortex continued to increase with stimulus duration but not with perceived stimulus intensity. Activation volumes in the left medial and right lateral thalamus, and the bilateral mid-anterior cingulate, left orbitofrontal, and right S2 cortices also increased only with stimulus duration. The increased activity of specific thalamic and cortical structures as stimulus duration, but not perceived intensity, increases is consistent with the recruitment of a thalamocortical mechanism that participates in the modulation of pain-related cortical responses and the temporal summation of heat pain. Published by Elsevier B.V.

  11. Childhood laterality and adult schizophrenia spectrum disorders: a prospective investigation

    DEFF Research Database (Denmark)

    Schiffman, Jason; Pestle, Sarah; Mednick, Sara

    2005-01-01

    Left or mixed-handedness, footedness, and eye dominance are thought to indicate abnormalities in lateralization related to schizophrenia. Increased left or mixed-dominance in schizophrenia suggests possible hemispheric abnormalities associated with the disorder. A related body of research suggests...... between children who later developed a schizophrenia spectrum disorder (n = 26) and those who did not develop a schizophrenia spectrum disorder (n = 216), among a high-risk and control, longitudinal sample. The rate of left or mixed-footedness, eye dominance, and any anomalous lateralization...

  12. Effect of left ventricular diastolic dysfunction on left atrial appendage function and thrombotic potential in nonvalvular atrial fibrillation.

    Science.gov (United States)

    Demirçelik, Muhammed Bora; Çetin, Mustafa; Çiçekcioğlu, Hülya; Uçar, Özgül; Duran, Mustafa

    2014-05-01

    We aimed to investigate effects of left ventricular diastolic dysfunction on left atrial appendage functions, spontaneous echo contrast and thrombus formation in patients with nonvalvular atrial fibrillation. In 58 patients with chronic nonvalvular atrial fibrilation and preserved left ventricular systolic function, left atrial appendage functions, left atrial spontaneous echo contrast grading and left ventricular diastolic functions were evaluated using transthoracic and transoesophageal echocardiogram. Patients divided in two groups: Group D (n=30): Patients with diastolic dysfunction, Group N (n=28): Patients without diastolic dysfunction. Categorical variables in two groups were evaluated with Pearson's chi-square or Fisher's exact test. The significance of the lineer correlation between the degree of spontaneous echo contrast (SEC) and clinical measurements was evaluated with Spearman's correlation analysis. Peak pulmonary vein D velocity of the Group D was significantly higher than the Group N (p=0.006). However, left atrial appendage emptying velocity, left atrial appendage lateral wall velocity, peak pulmonary vein S, pulmonary vein S/D ratio were found to be significantly lower in Group D (p=0.028, patrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities respectively (r=-0.438, r=-0.328, r=-0.233, r=-0.447). Left atrial appendage emptying, filling, pulmonary vein S/D levels and lateral wall velocities were significantly lower in SEC 2-3-4 than SEC 1 (p=0.003, p=0.029, patrial fibrillation and preserved left ventricular ejection fraction, left atrial appendage functions are decreased in patients with left ventricular diastolic dysfunction. Left ventricular diastolic dysfunction may constitute a potential risk for formation of thrombus and stroke.

  13. Comparison of IMP-SPECT findings to subtest scores of Wechsler intelligence adult Scale-Revised in temporal lobe epilepsy patients

    Energy Technology Data Exchange (ETDEWEB)

    Kan, Rumiko; Uejima, Masahiko; Kaneko, Yuko; Miyamoto, Yuriko; Watabe, Manabu; Takahashi, Ruriko; Niwa, Shin-ichi; Shishido, Fumio [Fukushima Medical Coll. (Japan)

    1998-02-01

    In this study, 40 temporal lobe epilepsy patients were assessed, using the Laterality Index (LI) of ROI values in IMP-SPECT findings, Wechsler adult intelligence Scale-Revised (WAIS-R) and subtest scores. LIs of the frontal, temporal and occipital lobes were calculated as follows: the ROI values on the right side were subtracted from those on the left, and the results was divided by the sum of the ROI values on the right and left sides. The individual subtest scores on WAIS-R were standardized by all evaluation scores in order to exclude the influence of differences in intelligence level as much as possible. The results were as follows: there was a positive correlation (r=0.74, p<0.001) between LI values and the performance in Arithmetic in the left temporal lobe hypoperfusion group. And there was a positive correlation (r=0.50, p<0.02) between LI values and the performance in Vocabulary in the left temporal lobe hypoperfusion group. In the right occipital lobe hypoperfusion group, there was a negative correlation (r=-O.44, p

  14. Comparison of IMP-SPECT findings to subtest scores of Wechsler intelligence adult Scale-Revised in temporal lobe epilepsy patients

    International Nuclear Information System (INIS)

    Kan, Rumiko; Uejima, Masahiko; Kaneko, Yuko; Miyamoto, Yuriko; Watabe, Manabu; Takahashi, Ruriko; Niwa, Shin-ichi; Shishido, Fumio

    1998-01-01

    In this study, 40 temporal lobe epilepsy patients were assessed, using the Laterality Index (LI) of ROI values in IMP-SPECT findings, Wechsler adult intelligence Scale-Revised (WAIS-R) and subtest scores. LIs of the frontal, temporal and occipital lobes were calculated as follows: the ROI values on the right side were subtracted from those on the left, and the results was divided by the sum of the ROI values on the right and left sides. The individual subtest scores on WAIS-R were standardized by all evaluation scores in order to exclude the influence of differences in intelligence level as much as possible. The results were as follows: there was a positive correlation (r=0.74, p<0.001) between LI values and the performance in Arithmetic in the left temporal lobe hypoperfusion group. And there was a positive correlation (r=0.50, p<0.02) between LI values and the performance in Vocabulary in the left temporal lobe hypoperfusion group. In the right occipital lobe hypoperfusion group, there was a negative correlation (r=-O.44, p< O.05) between LI values and the performance in Coding. It is suggested that decreased blood flow areas detected by SPECT might influence brain function. (author)

  15. Herniographic appearance of the lateral inguinal fossa

    International Nuclear Information System (INIS)

    Ekberg, O.; Kesek, P.

    1987-01-01

    Herniography frequently reveals clinically undetected groin hernia. Thereby herniography contributes to the clinical work-up in patients with obscure groin pain. However, the distinction between clinically important and unimportant abnormalities within the lateral inguinal fossa can be difficult. This study was therefore designed in order to elucidate the herniographic appearance of the lateral inguinal fossa in patients with obscure groin pain. Herniographic findings were compared with laterality of the patients' symptoms. The lateral umbilical fold was visible in only 47% of the groins. A triangular shaped outpouching from the lateral inguinal fossa and a patent processus vaginalis were found with equal frequency on the left and right side. They were five times as frequent in men as in women. Their presence did not correlate with laterality of the patients' symptoms. Indirect hernias were almost twice as common on the symptomatic side as compared with the asymptomatic side. On the left side they were found twice as often in men as in women while there was no significant sex difference on the right side. Our results show that neither a patent processus vaginalis nor a triangular outpouching from the lateral inguinal fossa correlate with the laterality of the patients' symptoms while true indirect hernias do. (orig.)

  16. Temporal pole signal abnormality on MR imaging in temporal lobe epilepsy with hippocampal sclerosis: a fluid-attenuated inversion-recovery study; Anormalidade de sinal na imagem por RM do polo temporal na epilepsia do lobo temporal com esclerose hipocampal: um estudo pela sequencia inversao recuperacao com supressao da agua livre (FLAIR)

    Energy Technology Data Exchange (ETDEWEB)

    Carrete Junior, Henrique; Abdala, Nitamar; Szjenfeld, Jacob; Nogueira, Roberto Gomes [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil). Dept. de Diagnostico por Imagem; Lin, Katia; Caboclo, Luis Otavio; Centeno, Ricardo Silva; Sakamoto, Americo Ceiki; Yacubian, Elza Marcia Targas [Universidade Federal de Sao Paulo (UNIFESP-EPM), Sao Paulo, SP (Brazil). Dept. de Neurologia e Neurocirurgia

    2007-09-15

    Objective: To determine the frequency and regional involvement of temporal pole signal abnormality (TPA) in patients with hippocampal sclerosis (HS) using fluid-attenuated inversion-recovery (FLAIR) MR imaging, and to correlate this feature with history. Method: Coronal FLAIR images of the temporal pole were assessed in 120 patients with HS and in 30 normal subjects, to evaluate gray-white matter demarcation. Results: Ninety (75%) of 120 patients had associated TPA. The HS side made difference regarding the presence of TPA, with a left side prevalence (p=0.04, {chi}{sup 2} test). The anteromedial zone of temporal pole was affected in 27 (30%) out of 90 patients. In 63 (70%) patients the lateral zone were also affected. Patients with TPA were younger at seizure onset (p=0.018), but without association with duration of epilepsy. Conclusion: Our FLAIR study show temporal pole signal abnormality in 3/4 of patients with HS, mainly seen on the anteromedial region, with a larger prevalence when the left hippocampus was involved. (author)

  17. Phase image characterization of ventricular contraction in left anterior hemiblock

    International Nuclear Information System (INIS)

    Ono, Akifumi; Mizuno, Haruyoshi; Tahara, Yorio; Ishikawa, Kyozo

    1991-01-01

    We investigated whether or not left anterior hemiblock is present in patients with left axis deviation using first-harmonic Fourier analysis of gated blood-pool images. Gated blood-pool images were taken in 50 patients without contraction abnormality. They included 14 normal subjects, 8 patients with right bundle branch block (RBBB), 20 with left axis deviation (LAD) and 8 with both RBBB and LAD (RBBB+LAD). ECG gated blood-pool scans were acquired in the anterior and 'best septal' left anterior oblique projections. First, the phase images were displayed cinematically as a continuous-loop movie. Next, for quantitative analysis of the phase image, the whole left ventricular and left ventricular high lateral regions of interest were drawn. The 'regional phase shift' (RPS) was then defined as {RPS=A-a} where 'A' is the mean value of the whole left ventricular phase angles and 'a' is that of phase angles in the high lateral region. The left ventricular phase changes and the RPSs in the RBBB and LAD groups were similar to those in the normal group. In the RBBB+LAD group, the latest phase changes occurred in the high anterolateral region. The RPSs of this group were significantly lower than those in the other 3 groups (p<0.01). These data suggest that left anterior hemiblock might coexist with RBBB in patients with RBBB+LAD, whereas left anterior hemiblock might not exist in the majority of patients with LAD alone. (author)

  18. Application of dynamic susceptibility contrast-enhanced perfusion in temporal lobe epilepsy

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Wu; Wang, Xiaoyi; Xie, Fangfang; Liao, Weihua [Dept. of Radiology, Xiangya Hospital of Central South Univ., Changsha (China)], e-mail: doctoring@sina.com

    2013-02-15

    Background: Accurately locatithe epileptogenic focus in temporal lobe epilepsy (TLE) is important in clinical practice. Single-photon emission computed tomography (SPECT) and positron-emission tomography (PET) have been widely used in the lateralization of TLE, but both have limitations. Magnetic resonance perfusion imaging can accurately and reliably reflect differences in cerebral blood flow and volume. Purpose: To investigate the diagnostic value of dynamic susceptibility contrast-enhanced (DSC) perfusion magnetic resonance imaging (MRI) in the lateralization of the epileptogenic focus in TLE. Material and Methods: Conventional MRI and DSC-MRI scanning was performed in 20 interictal cases of TLE and 20 healthy volunteers. The relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) of the bilateral mesial temporal lobes of the TLE cases and healthy control groups were calculated. The differences in the perfusion asymmetry indices (AIs), derived from the rCBV and rCBF of the bilateral mesial temporal lobes, were pared between the two groups. Results: In the control group, there were no statistically significant differences between the left and right sides in terms of rCBV (left 1.55 {+-} 0.32, right 1.57 {+-} 0.28) or rCBF (left 99.00 {+-} 24.61, right 100.38 {+-} 23.46) of the bilateral mesial temporal lobes. However, in the case group the ipsilateral rCBV and rCBF values (1.75 {+-} 0.64 and 96.35 {+-} 22.63, respectively) were markedly lower than those of the contralateral side (2.01 {+-} 0.79 and 108.56 {+-} 26.92; P < 0.05). Both the AI of the rCBV (AIrCBV; 13.03 {+-} 10.33) and the AI of the rCBF (AIrCBF; 11.24 {+-} 8.70) of the case group were significantly higher than that of the control group (AIrCBV 5.55 {+-} 3.74, AIrCBF 5.12 {+-} 3.48; P < 0.05). The epileptogenic foci of nine patients were correctly lateralized using the 95th percentile of the AIrCBV and AIrCBF of the control group as the normal upper limits. Conclusion: In

  19. Application of dynamic susceptibility contrast-enhanced perfusion in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Xing, Wu; Wang, Xiaoyi; Xie, Fangfang; Liao, Weihua

    2013-01-01

    Background: Accurately locatithe epileptogenic focus in temporal lobe epilepsy (TLE) is important in clinical practice. Single-photon emission computed tomography (SPECT) and positron-emission tomography (PET) have been widely used in the lateralization of TLE, but both have limitations. Magnetic resonance perfusion imaging can accurately and reliably reflect differences in cerebral blood flow and volume. Purpose: To investigate the diagnostic value of dynamic susceptibility contrast-enhanced (DSC) perfusion magnetic resonance imaging (MRI) in the lateralization of the epileptogenic focus in TLE. Material and Methods: Conventional MRI and DSC-MRI scanning was performed in 20 interictal cases of TLE and 20 healthy volunteers. The relative cerebral blood volume (rCBV) and relative cerebral blood flow (rCBF) of the bilateral mesial temporal lobes of the TLE cases and healthy control groups were calculated. The differences in the perfusion asymmetry indices (AIs), derived from the rCBV and rCBF of the bilateral mesial temporal lobes, were pared between the two groups. Results: In the control group, there were no statistically significant differences between the left and right sides in terms of rCBV (left 1.55 ± 0.32, right 1.57 ± 0.28) or rCBF (left 99.00 ± 24.61, right 100.38 ± 23.46) of the bilateral mesial temporal lobes. However, in the case group the ipsilateral rCBV and rCBF values (1.75 ± 0.64 and 96.35 ± 22.63, respectively) were markedly lower than those of the contralateral side (2.01 ± 0.79 and 108.56 ± 26.92; P < 0.05). Both the AI of the rCBV (AIrCBV; 13.03 ± 10.33) and the AI of the rCBF (AIrCBF; 11.24 ± 8.70) of the case group were significantly higher than that of the control group (AIrCBV 5.55 ± 3.74, AIrCBF 5.12 ± 3.48; P < 0.05). The epileptogenic foci of nine patients were correctly lateralized using the 95th percentile of the AIrCBV and AIrCBF of the control group as the normal upper limits. Conclusion: In patients with TLE interictal

  20. Evaluation of seizure propagation on ictal brain SPECT using statistical parametric mapping in temporal lobe epilepsy

    International Nuclear Information System (INIS)

    Jeon, Tae Joo; Lee, Jong Doo; Kim, Hee Joung; Lee, Byung In; Kim, Ok Joon; Kim, Min Jung; Jeon, Jeong Dong

    1999-01-01

    Ictal brain SPECT has a high diagnostic sensitivity exceeding 90 % in the localization of seizure focus, however, it often shows increased uptake within the extratemporal areas due to early propagation of seizure discharge. This study aimed to evaluate seizure propagation on ictal brian SPECT in patients with temporal lobe epilepsy (TLE) by statistical parametric mapping (SPM). Twenty-one patients (age 27.14 5.79 y) with temporal lobe epilepsy (right in 8, left in 13) who had successful seizure outcome after surgery and nine normal control were included. The data of ictal and interictal brain SPECT of the patients and baseline SPECT of normal control group were analyzed using automatic image registration and SPM96 softwares. The statistical analysis was performed to compare the mean SPECT image of normal group with individual ictal SPECT, and each mean image of the interictal groups of the right or left TLE with individual ictal scans. The t statistic SPM [t] was transformed to SPM [Z] with a threshold of 1.64. The statistical results were displayed and rendered on the reference 3 dimensional MRI images with P value of 0.05 and uncorrected extent threshold p value of 0.5 for SPM [Z]. SPM data demonstrated increased uptake within the epileptic lesion in 19 patients (90.4 %), among them, localized increased uptake confined to the epileptogenic lesion was seen in only 4 (19%) but 15 patients (71.4%) showed hyperperfusion within propagation sites. Bi-temporal hyperperfusion was observed in 11 out of 19 patients (57.9%, 5 in the right and 6 in the left); higher uptake within the lesion than contralateral side in 9, similar activity in 1 and higher uptake within contralateral lobe in one. Extra-temporal hyperperfusion was observed in 8 (2 in the right, 3 in the left, 3 in bilateral); unilateral hyperperfusion within the epileptogenic temporal lobe and extra-temporal area in 4, bi-temporal with extra-temporal hyperperfusion in remaining 4. Ictal brain SPECT is highly

  1. The Joint Development of Hemispheric Lateralization for Words and Faces

    Science.gov (United States)

    Dundas, Eva M.; Plaut, David C.; Behrmann, Marlene

    2013-01-01

    Consistent with long-standing findings from behavioral studies, neuroimaging investigations have identified a region of the inferior temporal cortex that, in adults, shows greater face selectivity in the right than left hemisphere and, conversely, a region that shows greater word selectivity in the left than right hemisphere. What has not been…

  2. Left-Deviating Prism Adaptation in Left Neglect Patient: Reflexions on a Negative Result

    Directory of Open Access Journals (Sweden)

    Jacques Luauté

    2012-01-01

    Full Text Available Adaptation to right-deviating prisms is a promising intervention for the rehabilitation of patients with left spatial neglect. In order to test the lateral specificity of prism adaptation on left neglect, the present study evaluated the effect of left-deviating prism on straight-ahead pointing movements and on several classical neuropsychological tests in a group of five right brain-damaged patients with left spatial neglect. A group of healthy subjects was also included for comparison purposes. After a single session of exposing simple manual pointing to left-deviating prisms, contrary to healthy controls, none of the patients showed a reliable change of the straight-ahead pointing movement in the dark. No significant modification of attentional paper-and-pencil tasks was either observed immediately or 2 hours after prism adaptation. These results suggest that the therapeutic effect of prism adaptation on left spatial neglect relies on a specific lateralized mechanism. Evidence for a directional effect for prism adaptation both in terms of the side of the visuomanual adaptation and therefore possibly in terms of the side of brain affected by the stimulation is discussed.

  3. Change in functional connectivity in tinnitus and its relation with tinnitus laterality

    Energy Technology Data Exchange (ETDEWEB)

    Song, Eun Jee; Kim, Eui Jong; Choi, Woo Suk [Dept. of Radiology, College of Medicine, Kyung Hee University, Seoul (Korea, Republic of); Ryu, Chang Woo; Jahang, Geon Ho; Park, Moon Suh; Byun, Jae Yong; Park, Soon Chan [Kyung Hee University Hospital at Gangdong, School of Medicine, Kyung Hee University, Seoul (Korea, Republic of)

    2016-12-15

    To identify potential differences in resting-state networks according to laterality of tinnitus using resting-state functional MRI (fMRI). A total of 83 age-matched subjects consisting of 19 patients with right-sided tinnitus (Rt-T), 22 patients with left-sided tinnitus (Lt-T), 22 patients with bilateral tinnitus (Bil-T), and 20 healthy controls underwent resting-state blood oxygenation-level dependent fMRI scans. Independent component analysis was used to obtain the functional connectivities in the auditory network (AN) and the default mode network (DMN), which were compared between each group using the voxel-wise one-way ANOVA. In addition, lateralization of the auditory cortex was assessed within each group using a region of interest (ROI). Comparisons between tinnitus groups showed unusual clusters with different functional connectivities in the AN and the DMN. The Rt-T group had large clusters with higher functional connectivity in the right middle temporal gyrus and temporopolar area compared with the Lt-/Bil-T and control groups. ROI analysis showed that the Rt-/Lt-T groups had dominant functional connectivity in the right auditory cortex and the Bil-T and control groups had left-dominant auditory connectivity. These results suggest that chronic tinnitus is related to aberrant laterality of the auditory cortex. These findings help clarify the neural mechanism of tinnitus and specify the targets for localization of treatment.

  4. Change in functional connectivity in tinnitus and its relation with tinnitus laterality

    International Nuclear Information System (INIS)

    Song, Eun Jee; Kim, Eui Jong; Choi, Woo Suk; Ryu, Chang Woo; Jahang, Geon Ho; Park, Moon Suh; Byun, Jae Yong; Park, Soon Chan

    2016-01-01

    To identify potential differences in resting-state networks according to laterality of tinnitus using resting-state functional MRI (fMRI). A total of 83 age-matched subjects consisting of 19 patients with right-sided tinnitus (Rt-T), 22 patients with left-sided tinnitus (Lt-T), 22 patients with bilateral tinnitus (Bil-T), and 20 healthy controls underwent resting-state blood oxygenation-level dependent fMRI scans. Independent component analysis was used to obtain the functional connectivities in the auditory network (AN) and the default mode network (DMN), which were compared between each group using the voxel-wise one-way ANOVA. In addition, lateralization of the auditory cortex was assessed within each group using a region of interest (ROI). Comparisons between tinnitus groups showed unusual clusters with different functional connectivities in the AN and the DMN. The Rt-T group had large clusters with higher functional connectivity in the right middle temporal gyrus and temporopolar area compared with the Lt-/Bil-T and control groups. ROI analysis showed that the Rt-/Lt-T groups had dominant functional connectivity in the right auditory cortex and the Bil-T and control groups had left-dominant auditory connectivity. These results suggest that chronic tinnitus is related to aberrant laterality of the auditory cortex. These findings help clarify the neural mechanism of tinnitus and specify the targets for localization of treatment

  5. Childhood laterality and adult schizophrenia spectrum disorders: a prospective investigation

    DEFF Research Database (Denmark)

    Schiffman, Jason; Pestle, Sarah; Mednick, Sara

    2005-01-01

    Left or mixed-handedness, footedness, and eye dominance are thought to indicate abnormalities in lateralization related to schizophrenia. Increased left or mixed-dominance in schizophrenia suggests possible hemispheric abnormalities associated with the disorder. A related body of research suggests...... that some indications of lateralization abnormalities may be evident prior to the onset of schizophrenia, suggesting that disruptions in lateralization are inherent to the developmental course of the disorder. We attempted to replicate and extend upon findings indicating differences in lateralization...... between children who later developed a schizophrenia spectrum disorder (n = 26) and those who did not develop a schizophrenia spectrum disorder (n = 216), among a high-risk and control, longitudinal sample. The rate of left or mixed-footedness, eye dominance, and any anomalous lateralization...

  6. Auras and clinical features in temporal lobe epilepsy: a new approach on the basis of voxel-based morphometry.

    Science.gov (United States)

    Santana, Maria Teresa Castilho Garcia; Jackowski, Andrea Parolin; da Silva, Henrique Hattori; Caboclo, Luis Otávio Sales Ferreira; Centeno, Ricardo Silva; Bressan, Rodrigo A; Carrete, Henrique; Yacubian, Elza Márcia Targas

    2010-05-01

    MRI investigations in patients with temporal lobe epilepsy (TLE) with mesial temporal sclerosis (MTS) have demonstrated structural abnormalities extending beyond ipsilateral hippocampus which may be studied through voxel-based morphometry (VBM). We investigated brain morphology related to clinical features in patients with refractory TLE with MTS using VBM. One hundred patients with unilateral TLE with MTS (59 left) and 30 controls were enrolled. VBM5 was employed to analyze (1) hemispheric damage, (2) influence of initial precipitating injury (IPI): 23 patients with febrile seizures and 19 with status epilepticus, and (3) types of auras classified as: mesial, including psychic auras (19 patients); anterior mesio-lateral, as autonomic symptoms, specially epigastric auras (27 patients) and neocortical, which included auditory, vertiginous, somatosensory and visual auras (16 patients). (1) Left TLE patients presented more widespread gray matter volume (GMV) reductions affecting ipsilateral hippocampus, temporal neocortex, insula and also left uncus, precentral gyrus, thalamus, parietal lobule, cuneus and bilateral cingulum. (2) Febrile seizures group presented ipsilateral GMV reductions in hippocampus, neocortical temporal, frontal and occipital cortices, insula and cingulum. Status epilepticus group presented more widespread GMV reductions involving temporal and extratemporal lobes. (3) Patients with mesial auras showed significant ipsilateral GMV reductions in hippocampus and amygdala, particularly right TLE group, who presented greater extension of GMV reduction in the entorhinal cortex. Significant reductions in hippocampus, amygdala and insula were seen in patients with anterior mesio-lateral auras. This study evaluated a large number of TLE-MTS patients showing structural damage extending beyond hippocampus, and different types of IPI associated with the extension of brain damage. Subtypes of auras are related to different clusters of areas of GMV reductions in

  7. Anterior Temporal Lobe Tracks the Formation of Prejudice.

    Science.gov (United States)

    Spiers, Hugo J; Love, Bradley C; Le Pelley, Mike E; Gibb, Charlotte E; Murphy, Robin A

    2017-03-01

    Despite advances in understanding the brain structures involved in the expression of stereotypes and prejudice, little is known about the brain structures involved in their acquisition. Here, we combined fMRI, a task involving learning the valence of different social groups, and modeling of the learning process involved in the development of biases in thinking about social groups that support prejudice. Participants read descriptions of valenced behaviors performed by members of novel social groups, with majority groups being more frequently encountered during learning than minority groups. A model-based fMRI analysis revealed that the anterior temporal lobe tracked the trial-by-trial changes in the valence associated with each group encountered in the task. Descriptions of behavior by group members that deviated from the group average (i.e., prediction errors) were associated with activity in the left lateral PFC, dorsomedial PFC, and lateral anterior temporal cortex. Minority social groups were associated with slower acquisition rates and more activity in the ventral striatum and ACC/dorsomedial PFC compared with majority groups. These findings provide new insights into the brain regions that (a) support the acquisition of prejudice and (b) detect situations in which an individual's behavior deviates from the prejudicial attitude held toward their group.

  8. Temporal networks

    Science.gov (United States)

    Holme, Petter; Saramäki, Jari

    2012-10-01

    A great variety of systems in nature, society and technology-from the web of sexual contacts to the Internet, from the nervous system to power grids-can be modeled as graphs of vertices coupled by edges. The network structure, describing how the graph is wired, helps us understand, predict and optimize the behavior of dynamical systems. In many cases, however, the edges are not continuously active. As an example, in networks of communication via e-mail, text messages, or phone calls, edges represent sequences of instantaneous or practically instantaneous contacts. In some cases, edges are active for non-negligible periods of time: e.g., the proximity patterns of inpatients at hospitals can be represented by a graph where an edge between two individuals is on throughout the time they are at the same ward. Like network topology, the temporal structure of edge activations can affect dynamics of systems interacting through the network, from disease contagion on the network of patients to information diffusion over an e-mail network. In this review, we present the emergent field of temporal networks, and discuss methods for analyzing topological and temporal structure and models for elucidating their relation to the behavior of dynamical systems. In the light of traditional network theory, one can see this framework as moving the information of when things happen from the dynamical system on the network, to the network itself. Since fundamental properties, such as the transitivity of edges, do not necessarily hold in temporal networks, many of these methods need to be quite different from those for static networks. The study of temporal networks is very interdisciplinary in nature. Reflecting this, even the object of study has many names-temporal graphs, evolving graphs, time-varying graphs, time-aggregated graphs, time-stamped graphs, dynamic networks, dynamic graphs, dynamical graphs, and so on. This review covers different fields where temporal graphs are considered

  9. DCDC2 polymorphism is associated with left temporoparietal gray and white matter structures during development.

    Science.gov (United States)

    Darki, Fahimeh; Peyrard-Janvid, Myriam; Matsson, Hans; Kere, Juha; Klingberg, Torkel

    2014-10-22

    Three genes, DYX1C1, DCDC2, and KIAA0319, have been previously associated with dyslexia, neuronal migration, and ciliary function. Three polymorphisms within these genes, rs3743204 (DYX1C1), rs793842 (DCDC2), and rs6935076 (KIAA0319) have also been linked to normal variability of left temporoparietal white matter volume connecting the middle temporal cortex to the angular and supramarginal gyri. Here, we assessed whether these polymorphisms are also related to the cortical thickness of the associated regions during childhood development using a longitudinal dataset of 76 randomly selected children and young adults who were scanned up to three times each, 2 years apart. rs793842 in DCDC2 was significantly associated with the thickness of left angular and supramarginal gyri as well as the left lateral occipital cortex. The cortex was significantly thicker for T-allele carriers, who also had lower white matter volume and lower reading comprehension scores. There was a negative correlation between white matter volume and cortical thickness, but only white matter volume predicted reading comprehension 2 years after scanning. These results show how normal variability in reading comprehension is related to gene, white matter volume, and cortical thickness in the inferior parietal lobe. Possibly, the variability of gray and white matter structures could both be related to the role of DCDC2 in ciliary function, which affects both neuronal migration and axonal outgrowth. Copyright © 2014 the authors 0270-6474/14/3414455-08$15.00/0.

  10. No Community Left Behind

    Science.gov (United States)

    Schlechty, Phillip C.

    2008-01-01

    The debate over the reauthorization of No Child Left Behind (NCLB) generally overlooks--or looks past--what may be the most fundamental flaw in that legislation. As the law is now written, decisions regarding what the young should know and be able to do are removed from the hands of parents and local community leaders and turned over to officials…

  11. The Children Left Behind

    Science.gov (United States)

    Gillard, Sarah A.; Gillard, Sharlett

    2012-01-01

    This article explores some of the deficits in our educational system in regard to non-hearing students. It has become agonizingly clear that non-hearing students are being left out of the gallant sweep to enrich our children's educations. The big five areas of literacy, at best, present unique challenges for non-hearing students and, in some…

  12. Left atrial appendage occlusion

    Directory of Open Access Journals (Sweden)

    Ahmad Mirdamadi

    2013-01-01

    Full Text Available Left atrial appendage (LAA occlusion is a treatment strategy to prevent blood clot formation in atrial appendage. Although, LAA occlusion usually was done by catheter-based techniques, especially percutaneous trans-luminal mitral commissurotomy (PTMC, it can be done during closed and open mitral valve commissurotomy (CMVC, OMVC and mitral valve replacement (MVR too. Nowadays, PTMC is performed as an optimal management of severe mitral stenosis (MS and many patients currently are treated by PTMC instead of previous surgical methods. One of the most important contraindications of PTMC is presence of clot in LAA. So, each patient who suffers of severe MS is evaluated by Trans-Esophageal Echocardiogram to rule out thrombus in LAA before PTMC. At open heart surgery, replacement of the mitral valve was performed for 49-year-old woman. Also, left atrial appendage occlusion was done during surgery. Immediately after surgery, echocardiography demonstrates an echo imitated the presence of a thrombus in left atrial appendage area, although there was not any evidence of thrombus in pre-pump TEE. We can conclude from this case report that when we suspect of thrombus of left atrial, we should obtain exact history of previous surgery of mitral valve to avoid misdiagnosis clotted LAA, instead of obliterated LAA. Consequently, it can prevent additional evaluations and treatments such as oral anticoagulation and exclusion or postponing surgeries including PTMC.

  13. Infant VEPs reveal neural correlates of implicit naming: Lateralized differences between lexicalized versus name-unknown pictures

    Science.gov (United States)

    Styles, Suzy J.; Plunkett, Kim; Duta, Mihaela D.

    2015-01-01

    Recent behavioural studies with toddlers have demonstrated that simply viewing a picture in silence triggers a cascade of linguistic processing which activates a representation of the picture’s name (Mani and Plunkett, 2010, 2011). Electrophysiological studies have also shown that viewing a picture modulates the auditory evoked potentials (AEPs) triggered by later speech, from early in the second year of life (Duta et al., 2012; Friedrich and Friederici, 2005; Mani et al., 2011) further supporting the notion that picture viewing gives rise to a representation of the picture’s name against which later speech can be matched. However, little is known about how and when the implicit name arises during picture viewing, or about the electrophysiological activity which supports this linguistic process. We report differences in the visual evoked potentials (VEPs) of fourteen-month-old infants who saw photographs of animals and objects, some of which were name-known (lexicalized), while waiting for an auditory label to be presented. During silent picture viewing, lateralized neural activity was selectively triggered by lexicalized items, as compared to nameless items. Lexicalized items generated a short-lasting negative-going deflection over frontal, left centro-temporal, and left occipital regions shortly after the picture appeared (126–225 ms). A positive deflection was also observed over the right hemisphere (particularly centro-temporal regions) in a later, longer-lasting window (421–720 ms). The lateralization of these differences in the VEP suggests the possible involvement of linguistic processes during picture viewing, and may reflect activity involved in the implicit activation of the picture’s name. PMID:26232744

  14. Hypoplastic left heart syndrome

    Directory of Open Access Journals (Sweden)

    Thiagarajan Ravi

    2007-05-01

    Full Text Available Abstract Hypoplastic left heart syndrome(HLHS refers to the abnormal development of the left-sided cardiac structures, resulting in obstruction to blood flow from the left ventricular outflow tract. In addition, the syndrome includes underdevelopment of the left ventricle, aorta, and aortic arch, as well as mitral atresia or stenosis. HLHS has been reported to occur in approximately 0.016 to 0.036% of all live births. Newborn infants with the condition generally are born at full term and initially appear healthy. As the arterial duct closes, the systemic perfusion becomes decreased, resulting in hypoxemia, acidosis, and shock. Usually, no heart murmur, or a non-specific heart murmur, may be detected. The second heart sound is loud and single because of aortic atresia. Often the liver is enlarged secondary to congestive heart failure. The embryologic cause of the disease, as in the case of most congenital cardiac defects, is not fully known. The most useful diagnostic modality is the echocardiogram. The syndrome can be diagnosed by fetal echocardiography between 18 and 22 weeks of gestation. Differential diagnosis includes other left-sided obstructive lesions where the systemic circulation is dependent on ductal flow (critical aortic stenosis, coarctation of the aorta, interrupted aortic arch. Children with the syndrome require surgery as neonates, as they have duct-dependent systemic circulation. Currently, there are two major modalities, primary cardiac transplantation or a series of staged functionally univentricular palliations. The treatment chosen is dependent on the preference of the institution, its experience, and also preference. Although survival following initial surgical intervention has improved significantly over the last 20 years, significant mortality and morbidity are present for both surgical strategies. As a result pediatric cardiologists continue to be challenged by discussions with families regarding initial decision

  15. Dual Balloon-Occluded Retrograde Transvenous Obliteration of Gastric Varix Draining into the Left Adrenal Vein and Left Inferior Phrenic Vein

    International Nuclear Information System (INIS)

    Nishida, Norifumi; Ninoi, Teruhisa; Kitayama, Toshiaki; Yamamoto, Akira; Sakai, Yukimasa; Sato, Kimihiko; Hamuro, Masao; Nakamura, Kenji; Inoue, Yuichi; Yamada, Ryusaku

    2004-01-01

    A 66-year-old woman with a gastric varix, draining into a dilated left adrenal vein and a left inferior phrenic vein, was treated with dual balloon-occluded retrograde transvenous obliteration (B-RTO). Under balloon occlusion of the left adrenal vein and the left inferior phrenic vein, retrograde injection of a sclerosant (5% ethanolamine oleate) into the gastric varix was performed. Two weeks later, disappearance of flow in the gastric varix was confirmed on endoscopic ultrasound examination

  16. Temporal naturalism

    Science.gov (United States)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  17. 99mTc-HMPAO SPECT in dementia of the Alzheimer type. Hypoperfusion in the medial temporal region

    International Nuclear Information System (INIS)

    Nakamura, Yu; Kawakatsu, Shinobu; Shinohara, Masao; Nadaoka, Toshihide; Totsuka, Shiro; Komatani, Akio

    1995-01-01

    This study examined regional cerebral blood flow (rCBF) by single photon emission computed tomography (SPECT) using technetium 99m-hexamethyl-propyleneamineoxime and correlated the results with neuropsychological findings in 30 patients with dementia of the Alzheimer type (AT dementia). Ten healthy persons served as controls. The group of mild AT dementia exhibited a significant decrease in rCBF in the lower part of the right lateral frontal lobe and in the right parietal lobe. In the group of moderate AT dementia, the significant decrease in rCBF was noted in the lower part of the bilateral frontal lobes, the parietal part of the temporal lobe, the parietal lobe, and the medial temporal lobe. Factor analysis for neuropsychological test revealed three factors involved in rCBF. There was a significantly positive correlation between the factor responsible for memory and recall and rCBF in the left frontal lobe, the anterior part of the lateral temporal lobe, and the medial temporal lobe. These findings suggested that disturbance of the memory circuit may exist in the medial temporal lobe and others as pathophysiology of AT dementia. (N.K.)

  18. Left Right Patterning, Evolution and Cardiac Development

    Science.gov (United States)

    Dykes, Iain M.

    2018-01-01

    Many aspects of heart development are determined by the left right axis and as a result several congenital diseases have their origins in aberrant left-right patterning. Establishment of this axis occurs early in embryogenesis before formation of the linear heart tube yet impacts upon much later morphogenetic events. In this review I discuss the differing mechanisms by which left-right polarity is achieved in the mouse and chick embryos and comment on the evolution of this system. I then discus three major classes of cardiovascular defect associated with aberrant left-right patterning seen in mouse mutants and human disease. I describe phenotypes associated with the determination of atrial identity and venous connections, looping morphogenesis of the heart tube and finally the asymmetric remodelling of the embryonic branchial arch arterial system to form the leftward looped arch of aorta and associated great arteries. Where appropriate, I consider left right patterning defects from an evolutionary perspective, demonstrating how developmental processes have been modified in species over time and illustrating how comparative embryology can aide in our understanding of congenital heart disease. PMID:29755990

  19. Developmental dyslexia: dysfunction of a left hemisphere reading network

    Directory of Open Access Journals (Sweden)

    Fabio eRichlan

    2012-05-01

    Full Text Available This mini-review summarizes and integrates findings from recent meta-analyses and original neuroimaging studies on functional brain abnormalities in dyslexic readers. Surprisingly, there is little empirical support for the standard neuroanatomical model of developmental dyslexia, which localizes the primary phonological decoding deficit in left temporo-parietal regions. Rather, recent evidence points to a dysfunction of a left hemisphere reading network, which includes occipito-temporal, inferior frontal, and inferior parietal regions.

  20. Unusual Association Between Spontaneous Lateral Sphenoid Encephalocele and Chiari Malformation Type I: Endoscopic Repair Through a Transpterygoid Approach.

    Science.gov (United States)

    Starnoni, Daniele; Daniel, Roy Thomas; George, Mercy; Messerer, Mahmoud

    2017-01-01

    Spontaneous meningoencephaloceles of the lateral sphenoid sinus are rare entities, and their peculiar location represents a surgical challenge due to the importance of a wide exposure and skull base reconstruction. They are thought to arise from the congenital base defect of the lateral sphenoid or in some cases have been postulated to represent a rare manifestation of altered cerebrospinal fluid (CSF) dynamics. We report the first case in the literature of a Chiari malformation type I (CMI) and a lateral sphenoid encephalocele, revising the theoretic etiology and surgical technique of endoscopic repair. A 50-year-old woman with a surgical history of symptomatic CMI presented with episodes of spontaneous CSF rhinorrhea. Radiologic investigations revealed a left mesial temporal encephalocele herniating into the lateral recess of the sphenoid sinus and radiologic features of altered CSF dynamics, which may have played an etiologic role. An endoscopic transpterygoid excision of the encephalocele and multilayer skull base repair were performed. The association of spontaneous lateral sphenoid encephaloceles with CMI is distinctly unusual. Predisposing factors and disruption of CSF dynamics may play a major role in the development of these rare complications in patients with CMI. Because of their distinct location, transethmoid or transpterygoid endoscopic approaches represent an excellent surgical technique to treat these lesions thanks to their wide and direct visualization of the entire skull base defect following the encephalocele excision, allowing an adequate multilayer repair and lateral sphenoid recess occlusion. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. The lateralization of motor cortex activation to action words

    Directory of Open Access Journals (Sweden)

    Olaf eHauk

    2011-11-01

    Full Text Available What determines the laterality of activation in motor cortex for words whose meaning is related to bodily actions? It has been suggested that the neuronal representation of the meaning of action-words is shaped by individual experience. However, core language functions are left-lateralized in the majority of both right- and left-handers. It is still an open question to what degree connections between left-hemispheric core language areas and right-hemispheric motor areas can play a role in semantics. We investigated laterality of brain activation using fMRI in right- and left-handed participants in response to visually presented hand-related action-words, namely uni- and bi-manual actions (such as "throw" and "clap". These stimulus groups were matched with respect to general (hand-action-relatedness, but differed with respect to whether they are usually performed with the dominant hand or both hands. We may expect generally more left-hemispheric motor-cortex activation for hand-related words in both handedness groups, with possibly more bilateral activation for bimanual words as well as left-handers. In our study, both participant groups activated motor cortex bilaterally for bi-manual words. Interestingly, both groups also showed a left-lateralized activation pattern to uni-manual words. We argue that this reflects the effect of left-hemispheric language dominance on the formation of semantic brain circuits on the basis of Hebbian correlation learning.

  2. A Novel Functional Magnetic Resonance Imaging Paradigm for the Preoperative Assessment of Auditory Perception in a Musician Undergoing Temporal Lobe Surgery.

    Science.gov (United States)

    Hale, Matthew D; Zaman, Arshad; Morrall, Matthew C H J; Chumas, Paul; Maguire, Melissa J

    2018-03-01

    Presurgical evaluation for temporal lobe epilepsy routinely assesses speech and memory lateralization and anatomic localization of the motor and visual areas but not baseline musical processing. This is paramount in a musician. Although validated tools exist to assess musical ability, there are no reported functional magnetic resonance imaging (fMRI) paradigms to assess musical processing. We examined the utility of a novel fMRI paradigm in an 18-year-old left-handed pianist who underwent surgery for a left temporal low-grade ganglioglioma. Preoperative evaluation consisted of neuropsychological evaluation, T1-weighted and T2-weighted magnetic resonance imaging, and fMRI. Auditory blood oxygen level-dependent fMRI was performed using a dedicated auditory scanning sequence. Three separate auditory investigations were conducted: listening to, humming, and thinking about a musical piece. All auditory fMRI paradigms activated the primary auditory cortex with varying degrees of auditory lateralization. Thinking about the piece additionally activated the primary visual cortices (bilaterally) and right dorsolateral prefrontal cortex. Humming demonstrated left-sided predominance of auditory cortex activation with activity observed in close proximity to the tumor. This study demonstrated an fMRI paradigm for evaluating musical processing that could form part of preoperative assessment for patients undergoing temporal lobe surgery for epilepsy. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Left Ventricular Assist Devices

    Directory of Open Access Journals (Sweden)

    Khuansiri Narajeenron

    2017-04-01

    Full Text Available Audience: The audience for this classic team-based learning (cTBL session is emergency medicine residents, faculty, and students; although this topic is applicable to internal medicine and family medicine residents. Introduction: A left ventricular assist device (LVAD is a mechanical circulatory support device that can be placed in critically-ill patients who have poor left ventricular function. After LVAD implantation, patients have improved quality of life.1 The number of LVAD patients worldwide continues to rise. Left-ventricular assist device patients may present to the emergency department (ED with severe, life-threatening conditions. It is essential that emergency physicians have a good understanding of LVADs and their complications. Objectives: Upon completion of this cTBL module, the learner will be able to: 1 Properly assess LVAD patients’ circulatory status; 2 appropriately resuscitate LVAD patients; 3 identify common LVAD complications; 4 evaluate and appropriately manage patients with LVAD malfunctions. Method: The method for this didactic session is cTBL.

  4. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    Energy Technology Data Exchange (ETDEWEB)

    Rademacher, J.; Seitz, R.J. [Department of Neurology, Heinrich-Heine University Duesseldorf (Germany); Aulich, A. [Department of Radiology, Heinrich-Heine University, Duesseldorf (Germany); Reifenberger, G. [Department of Neuropathology, Heinrich-Heine University, Duesseldorf (Germany); Kiwit, J.C.W. [Department of Neurosurgery, Heinrich-Heine University, Duesseldorf (Germany); Langen, K.J.; Schmidt, D. [Institute of Medicine, Research Center Juelich, Heinrich-Heine University, Duesseldorf (Germany)

    2000-06-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[{sup 123}I]iodo-{alpha}-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  5. Focal cortical dysplasia of the temporal lobe with late-onset partial epilepsy: serial quantitative MRI

    International Nuclear Information System (INIS)

    Rademacher, J.; Seitz, R.J.; Aulich, A.; Reifenberger, G.; Kiwit, J.C.W.; Langen, K.J.; Schmidt, D.

    2000-01-01

    We describe serial studies of focal cortical dysplasia causing temporal lobe seizures and progressive aphasia in a 54-year-old woman. Initially, MRI volumetry of the temporal lobes showed significant left cortical thickening corresponding to an elevated aminoacid uptake in the left temporoparietal and inferior frontal cortex on SPECT using 3-[ 123 I]iodo-α-methyl-l-tyrosine (IMT). After 1 year there was severe shrinkage of the left temporal lobe, possibly the result of recurrent complex partial seizures. (orig.)

  6. Mapping hemispheric symmetries, relative asymmetries, and absolute asymmetries underlying the auditory laterality effect.

    Science.gov (United States)

    Westerhausen, René; Kompus, Kristiina; Hugdahl, Kenneth

    2014-01-01

    Functional hemispheric differences for speech and language processing have been traditionally studied by using verbal dichotic-listening paradigms. The commonly observed right-ear preference for the report of dichotically presented syllables is taken to reflect the left hemispheric dominance for speech processing. However, the results of recent functional imaging studies also show that both hemispheres - not only the left - are engaged by dichotic listening, suggesting a more complex relationship between behavioral laterality and functional hemispheric activation asymmetries. In order to more closely examine the hemispheric differences underlying dichotic-listening performance, we report an analysis of functional magnetic resonance imaging (fMRI) data of 104 right-handed subjects, for the first time combining an interhemispheric difference and conjunction analysis. This approach allowed for a distinction of homotopic brain regions which showed symmetrical (i.e., brain region significantly activated in both hemispheres and no activation difference between the hemispheres), relative asymmetrical (i.e., activated in both hemispheres but significantly stronger in one than the other hemisphere), and absolute asymmetrical activation patterns (i.e., activated only in one hemisphere and this activation is significantly stronger than in the other hemisphere). Symmetrical activation was found in large clusters encompassing temporal, parietal, inferior frontal, and medial superior frontal regions. Relative and absolute left-ward asymmetries were found in the posterior superior temporal gyrus, located adjacent to symmetrically activated areas, and creating a lateral-medial gradient from symmetrical towards absolute asymmetrical activation within the peri-Sylvian region. Absolute leftward asymmetry was also found in the post-central and medial superior frontal gyri, while rightward asymmetries were found in middle temporal and middle frontal gyri. We conclude that dichotic

  7. Temporal contingency

    Science.gov (United States)

    Gallistel, C.R.; Craig, Andrew R.; Shahan, Timothy A.

    2015-01-01

    Contingency, and more particularly temporal contingency, has often figured in thinking about the nature of learning. However, it has never been formally defined in such a way as to make it a measure that can be applied to most animal learning protocols. We use elementary information theory to define contingency in such a way as to make it a measurable property of almost any conditioning protocol. We discuss how making it a measurable construct enables the exploration of the role of different contingencies in the acquisition and performance of classically and operantly conditioned behavior. PMID:23994260

  8. Temporal contingency.

    Science.gov (United States)

    Gallistel, C R; Craig, Andrew R; Shahan, Timothy A

    2014-01-01

    Contingency, and more particularly temporal contingency, has often figured in thinking about the nature of learning. However, it has never been formally defined in such a way as to make it a measure that can be applied to most animal learning protocols. We use elementary information theory to define contingency in such a way as to make it a measurable property of almost any conditioning protocol. We discuss how making it a measurable construct enables the exploration of the role of different contingencies in the acquisition and performance of classically and operantly conditioned behavior. Copyright © 2013 Elsevier B.V. All rights reserved.

  9. Lateral collateral ligament (image)

    Science.gov (United States)

    The lateral collateral ligament connects the end of the femur (thigh) to the top of the fibula (the thin bone that runs next to the shin bone). The lateral collateral ligament provides stability against varus stress. Varus stress ...

  10. Prolonged lateral steep position impairs respiratory mechanics during continuous lateral rotation therapy in respiratory failure.

    Science.gov (United States)

    Schellongowski, Peter; Losert, Heidrun; Locker, Gottfried J; Laczika, Klaus; Frass, Michael; Holzinger, Ulrike; Bojic, Andja; Staudinger, Thomas

    2007-04-01

    To establish whether prolonged lateral steep position during continuous rotation therapy leads to improvement on pulmonary gas exchange, respiratory mechanics and hemodynamics. Prospective observational study. Intensive care unit of a university hospital. Twelve consecutive patients suffering from acute lung injury or adult respiratory distress syndrome undergoing continuous rotation therapy. Blood gas analysis, static lung compliance, blood pressure, cardiac index and pulmonary shunt fraction were measured in supine as well as in left and right lateral steep position at 62 degrees during continuous rotation therapy (phase I). Rotation was then stopped for 30 min with the patients in supine position, left and right lateral steep position, and the same measurements were performed every 10 min (phase II). Phase I and II revealed no significant changes in PaO(2)/FiO(2) ratio, mean arterial blood pressure, pulmonary shunt fraction, or cardiac index. Significantly lower static compliance was observed in lateral steep position than in supine position (pposition than in left and right lateral steep position (ppositioning impairs the compliance of the respiratory system. Prolonged lateral steep position does not lead to benefits with respect to oxygenation or hemodynamics. Individual response to the different positions is unpredictable. The pauses in "extreme" positions should be as short as possible.

  11. Laterality effects in functional connectivity of the angular gyrus during rest and episodic retrieval.

    Science.gov (United States)

    Bellana, Buddhika; Liu, Zhongxu; Anderson, John A E; Moscovitch, Morris; Grady, Cheryl L

    2016-01-08

    The angular gyrus (AG) is consistently reported in neuroimaging studies of episodic memory retrieval and is a fundamental node within the default mode network (DMN). Its specific contribution to episodic memory is debated, with some suggesting it is important for the subjective experience of episodic recollection, rather than retrieval of objective episodic details. Across studies of episodic retrieval, the left AG is recruited more reliably than the right. We explored functional connectivity of the right and left AG with the DMN during rest and retrieval to assess whether connectivity could provide insight into the nature of this laterality effect. Using data from the publically available 1000 Functional Connectome Project, 8min of resting fMRI data from 180 healthy young adults were analysed. Whole-brain functional connectivity at rest was measured using a seed-based Partial Least Squares (seed-PLS) approach (McIntosh and Lobaugh, 2004) with bilateral AG seeds. A subsequent analysis used 6-min of rest and 6-min of unconstrained, silent retrieval of autobiographical events from a new sample of 20 younger adults. Analysis of this dataset took a more targeted approach to functional connectivity analysis, consisting of univariate pairwise correlations restricted to nodes of the DMN. The seed-PLS analysis resulted in two Latent Variables that together explained ~86% of the shared cross-block covariance. The first LV revealed a common network consistent with the DMN and engaging the AG bilaterally, whereas the second LV revealed a less robust, yet significant, laterality effect in connectivity - the left AG was more strongly connected to the DMN. Univariate analyses of the second sample again revealed better connectivity between the left AG and the DMN at rest. However, during retrieval the left AG was more strongly connected than the right to non-medial temporal (MTL) nodes of the DMN, and MTL nodes were more strongly connected to the right AG. The multivariate

  12. Mapping a lateralization gradient within the ventral stream for auditory speech perception

    OpenAIRE

    Specht, Karsten

    2013-01-01

    Recent models on speech perception propose a dual-stream processing network, with a dorsal stream, extending from the posterior temporal lobe of the left hemisphere through inferior parietal areas into the left inferior frontal gyrus, and a ventral stream that is assumed to originate in the primary auditory cortex in the upper posterior part of the temporal lobe and to extend toward the anterior part of the temporal lobe, where it may connect to the ventral part of the inferior frontal gyrus....

  13. 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.

  14. The question of symptom lateralization in conversion disorder

    NARCIS (Netherlands)

    Roelofs, K.; Näring, G.W.B.; Moene, F.C.; Hoogduin, C.A.L.

    2000-01-01

    Objective: The purpose of this study was to determine whether or not conversion symptoms are lateralized. Studies have shown a predominant left-oriented manifestation of symptoms for most somatoform disorders. The reports in the literature on the lateralization of conversion symptoms, however, are

  15. Left regular bands of groups of left quotients

    International Nuclear Information System (INIS)

    El-Qallali, A.

    1988-10-01

    A semigroup S which has a left regular band of groups as a semigroup of left quotients is shown to be the semigroup which is a left regular band of right reversible cancellative semigroups. An alternative characterization is provided by using spinned products. These results are applied to the case where S is a superabundant whose set of idempotents forms a left normal band. (author). 13 refs

  16. Why Dora Left

    DEFF Research Database (Denmark)

    Gammelgård, Judy

    2017-01-01

    The question of why Dora left her treatment before it was brought to a satisfactory end and the equally important question of why Freud chose to publish this problematic and fragmentary story have both been dealt with at great length by Freud’s successors. Dora has been read by analysts, literary...... problem toward femininity, both Dora’s and his own. In Dora, it is argued, Freud took a new stance toward the object of his investigation, speaking from the position of the master. Freud presents himself as the one who knows, in great contrast to the position he takes when unraveling the dream. Here he...

  17. Neutrosophic Left Almost Semigroup

    Directory of Open Access Journals (Sweden)

    Mumtaz Ali

    2014-06-01

    Full Text Available In this paper we extend the theory of neutrosophy to study left almost semigroup shortly LAsemigroup. We generalize the concepts of LA-semigroup to form that for neutrosophic LA-semigroup. We also extend the ideal theory of LA-semigroup to neutrosophy and discuss different kinds of neutrosophic ideals. We also find some new type of neutrosophic ideal which is related to the strong or pure part of neutrosophy. We have given many examples to illustrate the theory of neutrosophic LA-semigroup and display many properties of neutrosophic LA-semigroup in this paper.

  18. Decreasing Temporal Lobe Dose With Five-Field Intensity-Modulated Radiotherapy for Treatment of Pituitary Macroadenomas

    International Nuclear Information System (INIS)

    Parhar, Preeti K.; Duckworth, Tamara; Shah, Parinda; DeWyngaert, J. Keith; Narayana, Ashwatha; Formenti, Silvia C.; Shah, Jinesh N.

    2010-01-01

    Purpose: To compare temporal lobe dose delivered by three pituitary macroadenoma irradiation techniques: three-field three-dimensional conformal radiotherapy (3D-CRT), three-field intensity-modulated radiotherapy (3F IMRT), and a proposed novel alternative of five-field IMRT (5F IMRT). Methods and Materials: Computed tomography-based external beam radiotherapy planning was performed for 15 pituitary macroadenoma patients treated at New York University between 2002 and 2007 using: 3D-CRT (two lateral, one midline superior anterior oblique [SAO] beams), 3F IMRT (same beam angles), and 5F IMRT (same beam angles with additional right SAO and left SAO beams). Prescription dose was 45 Gy. Target volumes were: gross tumor volume (GTV) = macroadenoma, clinical target volume (CTV) = GTV, and planning target volume = CTV + 0.5 cm. Structure contouring was performed by two radiation oncologists guided by an expert neuroradiologist. Results: Five-field IMRT yielded significantly decreased temporal lobe dose delivery compared with 3D-CRT and 3F IMRT. Temporal lobe sparing with 5F IMRT was most pronounced at intermediate doses: mean V25Gy (% of total temporal lobe volume receiving ≥25 Gy) of 13% vs. 28% vs. 29% for right temporal lobe and 14% vs. 29% vs. 30% for left temporal lobe for 5F IMRT, 3D-CRT, and 3F IMRT, respectively (p -7 for 5F IMRT vs. 3D-CRT and 5F IMRT vs. 3F IMRT). Five-field IMRT plans did not compromise target coverage, exceed normal tissue dose constraints, or increase estimated brain integral dose. Conclusions: Five-field IMRT irradiation technique results in a statistically significant decrease in the dose to the temporal lobes and may thus help prevent neurocognitive sequelae in irradiated pituitary macroadenoma patients.

  19. Linear regression models for quantitative assessment of left ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-07-04

    Jul 4, 2008 ... of left ventricular function and structures using M-mode echocardiography ... Pearson's correlation coefficients were computed. Tests were two tailed ... tation may be problematic in some subjects. Excellent temporal ... excluded were subjects with obstructive airway disease, sickle cell disease, pregnancy ...

  20. Neural correlates of auditory temporal predictions during sensorimotor synchronization

    Directory of Open Access Journals (Sweden)

    Nadine ePecenka

    2013-08-01

    Full Text Available Musical ensemble performance requires temporally precise interpersonal action coordination. To play in synchrony, ensemble musicians presumably rely on anticipatory mechanisms that enable them to predict the timing of sounds produced by co-performers. Previous studies have shown that individuals differ in their ability to predict upcoming tempo changes in paced finger-tapping tasks (indexed by cross-correlations between tap timing and pacing events and that the degree of such prediction influences the accuracy of sensorimotor synchronization (SMS and interpersonal coordination in dyadic tapping tasks. The current functional magnetic resonance imaging study investigated the neural correlates of auditory temporal predictions during SMS in a within-subject design. Hemodynamic responses were recorded from 18 musicians while they tapped in synchrony with auditory sequences containing gradual tempo changes under conditions of varying cognitive load (achieved by a simultaneous visual n-back working-memory task comprising three levels of difficulty: observation only, 1-back, and 2-back object comparisons. Prediction ability during SMS decreased with increasing cognitive load. Results of a parametric analysis revealed that the generation of auditory temporal predictions during SMS recruits (1 a distributed network in cortico-cerebellar motor-related brain areas (left dorsal premotor and motor cortex, right lateral cerebellum, SMA proper and bilateral inferior parietal cortex and (2 medial cortical areas (medial prefrontal cortex, posterior cingulate cortex. While the first network is presumably involved in basic sensory prediction, sensorimotor integration, motor timing, and temporal adaptation, activation in the second set of areas may be related to higher-level social-cognitive processes elicited during action coordination with auditory signals that resemble music performed by human agents.

  1. Hemispheric lateralization of linguistic prosody recognition in comparison to speech and speaker recognition.

    Science.gov (United States)

    Kreitewolf, Jens; Friederici, Angela D; von Kriegstein, Katharina

    2014-11-15

    Hemispheric specialization for linguistic prosody is a controversial issue. While it is commonly assumed that linguistic prosody and emotional prosody are preferentially processed in the right hemisphere, neuropsychological work directly comparing processes of linguistic prosody and emotional prosody suggests a predominant role of the left hemisphere for linguistic prosody processing. Here, we used two functional magnetic resonance imaging (fMRI) experiments to clarify the role of left and right hemispheres in the neural processing of linguistic prosody. In the first experiment, we sought to confirm previous findings showing that linguistic prosody processing compared to other speech-related processes predominantly involves the right hemisphere. Unlike previous studies, we controlled for stimulus influences by employing a prosody and speech task using the same speech material. The second experiment was designed to investigate whether a left-hemispheric involvement in linguistic prosody processing is specific to contrasts between linguistic prosody and emotional prosody or whether it also occurs when linguistic prosody is contrasted against other non-linguistic processes (i.e., speaker recognition). Prosody and speaker tasks were performed on the same stimulus material. In both experiments, linguistic prosody processing was associated with activity in temporal, frontal, parietal and cerebellar regions. Activation in temporo-frontal regions showed differential lateralization depending on whether the control task required recognition of speech or speaker: recognition of linguistic prosody predominantly involved right temporo-frontal areas when it was contrasted against speech recognition; when contrasted against speaker recognition, recognition of linguistic prosody predominantly involved left temporo-frontal areas. The results show that linguistic prosody processing involves functions of both hemispheres and suggest that recognition of linguistic prosody is based on

  2. Brain and behavioral lateralization in invertebrates.

    Science.gov (United States)

    Frasnelli, Elisa

    2013-12-11

    Traditionally, only humans were thought to exhibit brain and behavioral asymmetries, but several studies have revealed that most vertebrates are also lateralized. Recently, evidence of left-right asymmetries in invertebrates has begun to emerge, suggesting that lateralization of the nervous system may be a feature of simpler brains as well as more complex ones. Here I present some examples in invertebrates of sensory and motor asymmetries, as well as asymmetries in the nervous system. I illustrate two cases where an asymmetric brain is crucial for the development of some cognitive abilities. The first case is the nematode Caenorhabditis elegans, which has asymmetric odor sensory neurons and taste perception neurons. In this worm left/right asymmetries are responsible for the sensing of a substantial number of salt ions, and lateralized responses to salt allow the worm to discriminate between distinct salt ions. The second case is the fruit fly Drosophila melanogaster, where the presence of asymmetry in a particular structure of the brain is important in the formation or retrieval of long-term memory. Moreover, I distinguish two distinct patterns of lateralization that occur in both vertebrates and invertebrates: individual-level and population-level lateralization. Theoretical models on the evolution of lateralization suggest that the alignment of lateralization at the population level may have evolved as an evolutionary stable strategy in which individually asymmetrical organisms must coordinate their behavior with that of other asymmetrical organisms. This implies that lateralization at the population-level is more likely to have evolved in social rather than in solitary species. I evaluate this new hypothesis with a specific focus on insects showing different level of sociality. In particular, I present a series of studies on antennal asymmetries in honeybees and other related species of bees, showing how insects may be extremely useful to test the evolutionary

  3. Brain and behavioural lateralization in invertebrates.

    Directory of Open Access Journals (Sweden)

    Elisa eFrasnelli

    2013-12-01

    Full Text Available Traditionally, only humans were thought to exhibit brain and behavioural asymmetries, but several studies have revealed that most vertebrates are also lateralized. Recently, evidence of left-right asymmetries in invertebrates has begun to emerge, suggesting that lateralization of the nervous system may be a feature of simpler brains as well as more complex ones. Here I present some examples in invertebrates of sensory and motor asymmetries, as well as asymmetries in the nervous system. I illustrate two cases where an asymmetric brain is crucial for the development of some cognitive abilities. The first case is the nematode C. elegans, which has asymmetric odour sensory neurons and taste perception neurons. In this worm left/right asymmetries are responsible for the sensing of a substantial number of salt ions, and lateralized responses to salt allow the worm to discriminate between distinct salt ions. The second case is the fruit fly D. melanogaster, where the presence of asymmetry in a particular structure of the brain is important in the formation or retrieval of long-term memory. Moreover, I distinguish two distinct patterns of lateralization that occur in both vertebrates and invertebrates: individual-level and population-level lateralization. Theoretical models on the evolution of lateralization suggest that the alignment of lateralization at the population level may have evolved as an evolutionary stable strategy in which individually-asymmetrical organisms must coordinate their behaviour with that of other asymmetrical organisms. This implies that lateralization at the population-level is more likely to have evolved in social rather than in solitary species. I evaluate this new hypothesis with specific focus on insects showing different level of sociality. In particular, I present a series of studies on antennal asymmetries in honeybees and other related species of bees, showing how insects may be extremely useful to test evolutionary

  4. Parahippocampal Involvement in Mesial Temporal Lobe Epilepsy with Hippocampal Sclerosis: A Proof of Concept from Memory-Guided Saccades

    Directory of Open Access Journals (Sweden)

    Silvia Colnaghi

    2017-11-01

    Full Text Available ObjectiveMesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS may involve extrahippocampal areas of structural damage and dysfunction. The accuracy of medium-term spatial memory can be tested by memory-guided saccades (MGS to evaluate a functional impairment of the parahippocampal cortex (PHC, while voxel-based morphometry (VBM analysis can be used to detect a structural damage of the latter region.MethodsMGS with 3- and 30-s memorization delays were compared between 7 patients affected by right MTLE-HS (r-MTLE-HS, 6 patients affected by left MTLE-HS, and 13 healthy controls. The same subjects underwent brain MRI for a VBM analysis. Correlation analysis was performed between the results of VBM and MGS and with patients’ clinical data.ResultsRight MTLE-HS patients showed impaired accuracy of leftward MGS with a 30-s memorization delay; their gray-matter volume was reduced in the right hippocampus and inferior temporal gyrus, and bilaterally in the cerebellum. Left MTLE-HS patients had normal MGS accuracy; their gray-matter volume was reduced in the left hippocampus, in the right-inferior temporal gyrus and corpus callosus, and bilaterally in the insular cortex and in the cerebellum. The difference between right and left parahippocampal volumes correlated with MGS accuracy, while right and left hippocampal volumes did not. Hippocampal and parahippocampal volume did not correlate with clinical variables such as febrile seizures, age at disease onset, disease duration, and seizure frequency.ConclusionMGS abnormalities suggested the functional involvement of the right PHC in patients with r-MTLE-HS, supporting a right lateralization of spatial memory control and showing a relation between functional impairment and degree of atrophy.

  5. The timing of associative memory formation: frontal lobe and anterior medial temporal lobe activity at associative binding predicts memory

    Science.gov (United States)

    Hales, J. B.

    2011-01-01

    The process of associating items encountered over time and across variable time delays is fundamental for creating memories in daily life, such as for stories and episodes. Forming associative memory for temporally discontiguous items involves medial temporal lobe structures and additional neocortical processing regions, including prefrontal cortex, parietal lobe, and lateral occipital regions. However, most prior memory studies, using concurrently presented stimuli, have failed to examine the temporal aspect of successful associative memory formation to identify when activity in these brain regions is predictive of associative memory formation. In the current study, functional MRI data were acquired while subjects were shown pairs of sequentially presented visual images with a fixed interitem delay within pairs. This design allowed the entire time course of the trial to be analyzed, starting from onset of the first item, across the 5.5-s delay period, and through offset of the second item. Subjects then completed a postscan recognition test for the items and associations they encoded during the scan and their confidence for each. After controlling for item-memory strength, we isolated brain regions selectively involved in associative encoding. Consistent with prior findings, increased regional activity predicting subsequent associative memory success was found in anterior medial temporal lobe regions of left perirhinal and entorhinal cortices and in left prefrontal cortex and lateral occipital regions. The temporal separation within each pair, however, allowed extension of these findings by isolating the timing of regional involvement, showing that increased response in these regions occurs during binding but not during maintenance. PMID:21248058

  6. Temporal Lobe Epilepsy Surgery Failures: A Review

    Science.gov (United States)

    Harroud, Adil; Bouthillier, Alain; Weil, Alexander G.; Nguyen, Dang Khoa

    2012-01-01

    Patients with temporal lobe epilepsy (TLE) are refractory to antiepileptic drugs in about 30% of cases. Surgical treatment has been shown to be beneficial for the selected patients but fails to provide a seizure-free outcome in 20–30% of TLE patients. Several reasons have been identified to explain these surgical failures. This paper will address the five most common causes of TLE surgery failure (a) insufficient resection of epileptogenic mesial temporal structures, (b) relapse on the contralateral mesial temporal lobe, (c) lateral temporal neocortical epilepsy, (d) coexistence of mesial temporal sclerosis and a neocortical lesion (dual pathology); and (e) extratemporal lobe epilepsy mimicking TLE or temporal plus epilepsy. Persistence of epileptogenic mesial structures in the posterior temporal region and failure to distinguish mesial and lateral temporal epilepsy are possible causes of seizure persistence after TLE surgery. In cases of dual pathology, failure to identify a subtle mesial temporal sclerosis or regions of cortical microdysgenesis is a likely explanation for some surgical failures. Extratemporal epilepsy syndromes masquerading as or coexistent with TLE result in incomplete resection of the epileptogenic zone and seizure relapse after surgery. In particular, the insula may be an important cause of surgical failure in patients with TLE. PMID:22934162

  7. Increased opacity of left pericardiac area on chest radiograph : correlation with CT findings and its frequency

    International Nuclear Information System (INIS)

    Lee, Seung Ik; Kim, Jeung Sook; Kwak, Jin Young; Ryu, Chang Woo; Yoon, Sam Hyun

    1998-01-01

    The purpose of this study was to evaluate the incidence of extrapericardial fat in the left cardiac border, and with regard to left extrapericardial fat, to correlate chest radiographs with CT scans. This study involved 132 consecutive patients who underwent chest PA and lateral radiographs, and chest CT scans. According to the results of chest PA radiograph, patients were divided into three groups: those with a clear left cardiac border; those with an indistinct left cardiac border; and those with an indistinct left cardiac border with increased density; cardiophrenic angle, as seen on lateral radiograph, the presence of increased density in the anterior cardiophrenic angle, as seen on lateral radiographs was evaluated. On the basis of the results of CT scanning, patients were classified into four groups according to the amount of left extrapericardial fat : negative, minimum, moderate, and maximum. Left extrapericardial fat, as seen on CT, was correlated with the conspicuity of left cardiac border seen on PA radiograph and the presence of increased density in the anterior cardiophrenic angle, as seen on lateral radiograph. The conspicuousness of the left cardiac border, as seen on PA chest radiograph, correlated with the presence of left extrapericardial fat, as seen on CT, and was related to the amount of left extrapericardial fat. Increased density of the anterior cardiophrenic angle, as seen on lateral radiographs, correlated with the presence of left extrapericardial fat on CT, but the absence of increased density on lateral radiograph corresponds to the absence or a minimal amount of left extrapericardial fat, as seen on CT. (author). 8 refs., 4 tabs., 3 figs

  8. [Left postpneumonectomy syndrome: early endoscopic treatment].

    Science.gov (United States)

    Rombolá, Carlos A; León Atance, Pablo; Honguero Martínez, Antonio Francisco; Rueda Martínez, Juan Luis; Núñez Ares, Ana; Vizcaya Sánchez, Manuel

    2009-12-01

    Postpneumonectomy syndrome is characterized by postoperative bronchial obstruction caused by mediastinal shift. The syndrome is well documented in the medical literature as a late complication of right pneumonectomy; however, it rarely occurs following resection of the left lung, and only 10 cases have been published. The pathophysiology, clinical manifestations, prognosis, and treatment are similar for both sides of the lung. We present the case of an adult patient who underwent left pneumonectomy and developed postpneumonectomy syndrome 15 months later. Stenosis of the intermediate bronchus occurred between the vertebral body and the right pulmonary artery. Endoscopic treatment with a self-expanding metal stent was successful, and complete remission was observed over the 6 months of follow-up.

  9. Brain lateralization and neural plasticity for musical and cognitive abilities in an epileptic musician

    Directory of Open Access Journals (Sweden)

    Isabel eTrujillo-Pozo

    2013-12-01

    Full Text Available The use of intracarotid propofol procedure (IPP when assessing musical lateralization has not been reported in literature up to now. This procedure (similar to Wada Test has provided the opportunity to investigate not only lateralization of language and memory functions on epileptic patients but also offers a functional mapping approach with superior spatial and temporal resolution to analyze the lateralization of musical abilities. Findings in literature suggest that musical training modifies functional and structural brain organization. We studied hemispheric lateralization in a professional musician, a 33 years old woman with refractory left medial temporal lobe epilepsy. A longitudinal neuropsychological study was performed over a period of 21 months. Before epilepsy surgery, musical abilities, language and memory were tested during IPP by means of a novel and exhaustive neuropsychological battery focusing on the processing of music. We used a selection of stimuli to analyze listening, score reading, and tempo discrimination. Our results suggested that IPP is an excellent method to determine not only language, semantic and episodic memory, but also musical dominance in a professional musician who may be candidate for epilepsy surgery. Neuropsychological testing revealed that right hemisphere’s patient is involved in semantic and episodic musical memory processes, whereas her score reading and tempo processing require contribution from both hemispheres. At 1-year follow-up, outcome was excellent with respect to seizures and professional skills, meanwhile cognitive abilities improved. These findings indicate that IPP helps to predict who might be at risk for postoperative musical, language and memory deficits after epilepsy surgery. Our research suggests that musical expertise and epilepsy critically modifies long-term memory processes and induces brain structural and functional plasticity.

  10. Cognitive impairments in patients with intractable temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Mahgol Tavakoli

    2011-01-01

    Conclusions: These findings indicated that WMS-III and WAIS-R can differentiate patients with refractory temporal lobe epilepsy from normal subjects. However, the obtained cognitive profile could not differentiate between the right and the left TLE.

  11. Triple pathological findings in a surgically amenable patient with mesial temporal lobe epilepsy

    Directory of Open Access Journals (Sweden)

    Fumin Tong

    2015-01-01

    Full Text Available Mesial temporal sclerosis (MTS is a well-recognized cause of intractable epilepsy; however, coexistence with focal cortical dysplasia (FCD is less common. Middle fossa epidermoid cysts are rare and may involve the temporal lobe. Most epidermoids are clinically silent, slow-growing, and seldom associated with overt symptomatology, including seizures. We describe a patient with multiple comorbidities including left MTS and a large epidermoid cyst involving the left quadrigeminal plate cistern compressing upon the cerebellar vermis and tail of the left hippocampus, resulting in refractory left temporal lobe epilepsy. The patient underwent left anterior temporal lobectomy. The surgical pathology demonstrated a third pathological finding of left temporal FCD type Ia. The patient has been seizure-free since the surgery. This case provides additional information with regard to the understanding of epileptogenicity and surgical planning in patients with MTS and epidermoid cysts.

  12. Annular subvalvular left ventricular aneurysm in Bahia, Brazil.

    Science.gov (United States)

    Guimarães, A C; Filho, A S; Esteves, J P; Abreu, W N; Vinhaes, L A; de Almeida Souza, J A; Machado, A

    1976-10-01

    Two cases of left ventricular aneurysm, a 16-year-old black boy and a 23-year-old white girl, from Bahia, Brazil, are presented. In both patients there was enlargement of the cardiac silhouette and a prominent bulge of the left inferior border. On the right oblique view a ring of calcium at the ventricular opening of the aneurysms was visualized. A left ventriculogram showed a huge aneurysm in the first case and a bulge on the lateral wall of the left ventricle in the other. Cardiac catheterization showed a rise in left and right ventricular end-diastolic pressures and in the mean pulmonary artery pressure. In the first case the contour of the right ventricular pressure curve showed a restrictive pattern. The similarities of these aneurysms with the annular submitral type described in young black Africans are stressed.

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

    Directory of Open Access Journals (Sweden)

    Daniel S. Barron

    2015-01-01

    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.

  14. Anosognosia for hemiparesis after left-sided stroke.

    Science.gov (United States)

    Baier, Bernhard; Vucurevic, Goran; Müller-Forell, Wibke; Glassl, Oliver; Geber, Christian; Dieterich, Marianne; Karnath, Hans-Otto

    2014-12-01

    In patients with left-sided lesions, anosognosia for hemiparesis (AHP) seems to be a rare phenomenon. It has been discussed whether this rareness might be due to an inevitable bias due to language dysfunction and whether the left hemisphere's role for our self-awareness of motor actions thus is underestimated. By applying functional magnetic resonance imaging (fMRI) we examined whether patients with AHP following a left hemisphere stroke show a regular, left-sided or a reversed, right-sided lateralization of language functions. Only the former observation would argue for an original role of the left hemisphere in self-awareness about limb function. In a consecutive series of 44 acute left-sided stroke patients, only one patient (=2%) was identified showing AHP. In this case, we could verify by using fMRI that lateralization of AHP and spatial neglect on the one hand and of language functions on the other hand were reversed. The present single case observation thus argues against an original role of the left hemisphere in self-awareness about limb function. We discuss the data in the context of previous observations in the literature. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. One declarative memory system or two? The relationship between episodic and semantic memory in children with temporal lobe epilepsy.

    Science.gov (United States)

    Smith, Mary Lou; Lah, Suncica

    2011-09-01

    This study explored verbal semantic and episodic memory in children with unilateral temporal lobe epilepsy to determine whether they had impairments in both or only 1 aspect of memory, and to examine relations between performance in the 2 domains. Sixty-six children and adolescents (37 with seizures of left temporal lobe onset, 29 with right-sided onset) were given 4 tasks assessing different aspects of semantic memory (picture naming, fluency, knowledge of facts, knowledge of word meanings) and 2 episodic memory tasks (story recall, word list recall). High rates of impairments were observed across tasks, and no differences were found related to the laterality of the seizures. Individual patient analyses showed that there was a double dissociation between the 2 aspects of memory in that some children were impaired on episodic but not semantic memory, whereas others showed intact episodic but impaired semantic memory. This double dissociation suggests that these 2 memory systems may develop independently in the context of temporal lobe pathology, perhaps related to differential effects of dysfunction in the lateral and mesial temporal lobe structures. PsycINFO Database Record (c) 2011 APA, all rights reserved.

  16. Temporal Glare

    DEFF Research Database (Denmark)

    Ritschel, Tobias; Ihrke, Matthias; Frisvad, Jeppe Revall

    2009-01-01

    Glare is a consequence of light scattered within the human eye when looking at bright light sources. This effect can be exploited for tone mapping since adding glare to the depiction of high-dynamic range (HDR) imagery on a low-dynamic range (LDR) medium can dramatically increase perceived contra...... to initially static HDR images. By conducting psychophysical studies, we validate that our method improves perceived brightness and that dynamic glare-renderings are often perceived as more attractive depending on the chosen scene.......Glare is a consequence of light scattered within the human eye when looking at bright light sources. This effect can be exploited for tone mapping since adding glare to the depiction of high-dynamic range (HDR) imagery on a low-dynamic range (LDR) medium can dramatically increase perceived contrast....... Even though most, if not all, subjects report perceiving glare as a bright pattern that fluctuates in time, up to now it has only been modeled as a static phenomenon. We argue that the temporal properties of glare are a strong means to increase perceived brightness and to produce realistic...

  17. Rectal volvulus following laparoscopic left hemicolectomy

    Science.gov (United States)

    Sutton, Paul Anthony; Lee, Han Sian; Din, Islah; Vimalachandran, Dale

    2013-01-01

    A 60-year-old lady with a history of Dukes B2 (T3N0M0) colorectal cancer presented some 2 years following a laparoscopic left hemicolectomy with a 4-day history of absolute constipation. A plain radiograph demonstrated large bowel obstruction, and subsequent CT of the abdomen showed the level of the obstruction to be at the rectum. Initially the aetiology was believed to be recurrence at the site of the anastomosis; however, subsequent review of the imaging and indeed endoscopic examination of the rectum showed it to be volvulus. This was initially treated with endoscopic decompression and later by the insertion of a flatus tube to good effect. The patient was discharged 3 days later with no recurrence of her symptoms at 2 months. PMID:23608861

  18. Arcuate fasciculus laterality by diffusion tensor imaging correlates with language laterality by functional MRI in preadolescent children.

    Science.gov (United States)

    Sreedharan, Ruma Madhu; Menon, Amitha C; James, Jija S; Kesavadas, Chandrasekharan; Thomas, Sanjeev V

    2015-03-01

    Language lateralization is unique to humans. Functional MRI (fMRI) and diffusion tensor imaging (DTI) enable the study of language areas and white matter fibers involved in language, respectively. The objective of this study was to correlate arcuate fasciculus (AF) laterality by diffusion tensor imaging with that by fMRI in preadolescent children which has not yet been reported. Ten children between 8 and 12 years were subjected to fMRI and DTI imaging using Siemens 1.5 T MRI. Two language fMRI paradigms--visual verb generation and word pair task--were used. Analysis was done using SPM8 software. In DTI, the fiber volume of the arcuate fasciculus (AFV) and fractional anisotropy (FA) was measured. The fMRI Laterality Index (fMRI-LI) and DTI Laterality Index (DTI-LI) were calculated and their correlation assessed using the Pearson Correlation Index. Of ten children, mean age 10.6 years, eight showed left lateralization while bilateral language lateralization was seen in two. AFV by DTI was more on the left side in seven of the eight children who had left lateralization by fMRI. DTI could not trace the AF in one child. Of the two with bilateral language lateralization on fMRI, one showed larger AFV on the right side while the other did not show any asymmetry. There was a significant correlation (p laterality in children with a high degree of correlation between the two imaging modalities.

  19. Do children with aggressive behavior have temporal lobe changes?

    International Nuclear Information System (INIS)

    Thomas, C.T.; Mishkin, F.; Goldberg, M.

    2002-01-01

    Aggressive behavior and mood disorders may afflict children. One problem is the lack of objective data to arrive at a specific clinical diagnosis. Abnormalities in neurotransmitters such as serotonin, dopamine, acetylcholine and gamma-aminobutyric acid have been reported to play an important role in the onset of these disorders. We studied 8 patients, 3 girls and 5 boys, ages ranging from 6 to 12, referred to us with the diagnosis of ADHD or autism and reported as having temper problems by their families. These patients were injected with a dose of Tc-99m HMPAO calculated according to patient age and weight and were imaged 1 hour later using a Picker camera with Fan Beam collimators. We analyzed the brain SPECT using 3D as well as the traditional transverse, coronal and sagittal images. With the help of surface rendered 3D images with a cut off of 88% (high) and 60-65% (lower value depending on the patient RCBF value), we observed increased perfusion or activation of either or both right and left temporal lobes in all 8 of the patients. This pattern was not seen in children whose parents did not report temper problems. Increase in perfusion to the temporal lobes may indicate an association with oppositional or aggressive behavior that may be amenable to treatment. Brain SPECT may be useful not only in early diagnosis, but also in guiding appropriate therapy

  20. Do children with aggressive behavior have temporal lobe changes?

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, C T; Mishkin, F; Goldberg, M [Department of Nuclear Medicine, Harbor-UCLA Medical Center, Torrance, CA (United States)

    2002-09-01

    Aggressive behavior and mood disorders may afflict children. One problem is the lack of objective data to arrive at a specific clinical diagnosis. Abnormalities in neurotransmitters such as serotonin, dopamine, acetylcholine and gamma-aminobutyric acid have been reported to play an important role in the onset of these disorders. We studied 8 patients, 3 girls and 5 boys, ages ranging from 6 to 12, referred to us with the diagnosis of ADHD or autism and reported as having temper problems by their families. These patients were injected with a dose of Tc-99m HMPAO calculated according to patient age and weight and were imaged 1 hour later using a Picker camera with Fan Beam collimators. We analyzed the brain SPECT using 3D as well as the traditional transverse, coronal and sagittal images. With the help of surface rendered 3D images with a cut off of 88% (high) and 60-65% (lower value depending on the patient RCBF value), we observed increased perfusion or activation of either or both right and left temporal lobes in all 8 of the patients. This pattern was not seen in children whose parents did not report temper problems. Increase in perfusion to the temporal lobes may indicate an association with oppositional or aggressive behavior that may be amenable to treatment. Brain SPECT may be useful not only in early diagnosis, but also in guiding appropriate therapy.

  1. Cerebral Lateralization of Face-Selective and Body-Selective Visual Areas Depends on Handedness

    NARCIS (Netherlands)

    Willems, R.M.; Peelen, M.V.; Hagoort, P.

    2010-01-01

    The left-hemisphere dominance for language is a core example of the functional specialization of the cerebral hemispheres. The degree of left-hemisphere dominance for language depends on hand preference: Whereas the majority of right-handers show left-hemispheric language lateralization, this number

  2. Cerebral lateralization of face-selective and body-selective visual areas depends on handedness

    NARCIS (Netherlands)

    Willems, R.M.; Peelen, M.V.; Hagoort, P.

    2010-01-01

    The left-hemisphere dominance for language is a core example of the functional specialization of the cerebral hemispheres. The degree of left-hemisphere dominance for language depends on hand preference: Whereas the majority of right-handers show left-hemispheric language lateralization, this number

  3. Gender and hemispheric differences in temporal lobe epilepsy: a VBM study.

    Science.gov (United States)

    Santana, Maria Teresa Castilho Garcia; Jackowski, Andrea Parolin; Britto, Fernanda Dos Santos; Sandim, Gabriel Barbosa; Caboclo, Luís Otávio Sales Ferreira; Centeno, Ricardo Silva; Carrete, Henrique; Yacubian, Elza Márcia Targas

    2014-04-01

    Gender differences are recognized in the functional and anatomical organization of the human brain. Differences between genders are probably expressed early in life, when differential rates of cerebral maturation occur. Sexual dimorphism has been described in temporal lobe epilepsy with mesial temporal sclerosis (TLE-MTS). Several voxel-based morphometry (VBM) studies have shown that TLE-MTS extends beyond mesial temporal structures, and that there are differences in the extent of anatomical damage between hemispheres, although none have approached gender differences. Our aim was to investigate gender differences and anatomical abnormalities in TLE-MTS. VBM5 was employed to analyze gender and hemispheric differences in 120 patients with TLE-MTS and 50 controls. VBM abnormalities were more widespread in left-TLE; while in women changes were mostly seen in temporal areas, frontal regions were more affected in men. Our study confirmed that gender and laterality are important factors determining the nature and severity of brain damage in TLE-MTS. Differential rates of maturation between gender and hemispheres may explain the distinct areas of anatomical damage in men and women. Copyright © 2013 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  4. Two distinct forms of functional lateralization in the human brain

    Science.gov (United States)

    Gotts, Stephen J.; Jo, Hang Joon; Wallace, Gregory L.; Saad, Ziad S.; Cox, Robert W.; Martin, Alex

    2013-01-01

    The hemispheric lateralization of certain faculties in the human brain has long been held to be beneficial for functioning. However, quantitative relationships between the degree of lateralization in particular brain regions and the level of functioning have yet to be established. Here we demonstrate that two distinct forms of functional lateralization are present in the left vs. the right cerebral hemisphere, with the left hemisphere showing a preference to interact more exclusively with itself, particularly for cortical regions involved in language and fine motor coordination. In contrast, right-hemisphere cortical regions involved in visuospatial and attentional processing interact in a more integrative fashion with both hemispheres. The degree of lateralization present in these distinct systems selectively predicted behavioral measures of verbal and visuospatial ability, providing direct evidence that lateralization is associated with enhanced cognitive ability. PMID:23959883

  5. Auditory temporal-order thresholds show no gender differences

    NARCIS (Netherlands)

    van Kesteren, Marlieke T. R.; Wierslnca-Post, J. Esther C.

    2007-01-01

    Purpose: Several studies on auditory temporal-order processing showed gender differences. Women needed longer inter-stimulus intervals than men when indicating the temporal order of two clicks presented to the left and right ear. In this study, we examined whether we could reproduce these results in

  6. Auditory temporal-order thresholds show no gender differences

    NARCIS (Netherlands)

    van Kesteren, Marlieke T R; Wiersinga-Post, J Esther C

    2007-01-01

    PURPOSE: Several studies on auditory temporal-order processing showed gender differences. Women needed longer inter-stimulus intervals than men when indicating the temporal order of two clicks presented to the left and right ear. In this study, we examined whether we could reproduce these results in

  7. Prevalence of left-sided melanomas in an Irish population.

    LENUS (Irish Health Repository)

    de Blacam, C

    2012-02-01

    BACKGROUND: A predominance of melanomas on the left side of the body has recently been described. No associations between tumour laterality and gender, age or anatomical site have been identified. AIM: The aim of this study was to investigate the prevalence of left-sided melanomas in an Irish population and to examine potential associations with various patient and tumour characteristics. METHODS: A retrospective chart review of patients with cutaneous melanoma who were treated over a 10-year period was carried out. Lateral distribution of melanoma on either side of the body was compared using chi(2) analysis and evaluated by gender, age group, anatomic location, histologic subtype and Breslow depth. RESULTS: More melanomas occurred on the left side (57%, P = 0.015), and this finding was particularly significant in females. For both genders combined, there were no statistically significant differences in laterality by age group, anatomic location, type of melanoma and Breslow depth. There were significantly more superficial spreading melanomas on the left side in both men and women. CONCLUSIONS: This study demonstrates a predominance of left-sided melanomas in Irish patients. While a number of demographic and molecular associations have been proposed, further research is required to fully explain this phenomenon.

  8. Prevalence of left-sided melanomas in an Irish population.

    LENUS (Irish Health Repository)

    de Blacam, C

    2011-04-17

    BACKGROUND: A predominance of melanomas on the left side of the body has recently been described. No associations between tumour laterality and gender, age or anatomical site have been identified. AIM: The aim of this study was to investigate the prevalence of left-sided melanomas in an Irish population and to examine potential associations with various patient and tumour characteristics. METHODS: A retrospective chart review of patients with cutaneous melanoma who were treated over a 10-year period was carried out. Lateral distribution of melanoma on either side of the body was compared using χ(2) analysis and evaluated by gender, age group, anatomic location, histologic subtype and Breslow depth. RESULTS: More melanomas occurred on the left side (57%, P = 0.015), and this finding was particularly significant in females. For both genders combined, there were no statistically significant differences in laterality by age group, anatomic location, type of melanoma and Breslow depth. There were significantly more superficial spreading melanomas on the left side in both men and women. CONCLUSIONS: This study demonstrates a predominance of left-sided melanomas in Irish patients. While a number of demographic and molecular associations have been proposed, further research is required to fully explain this phenomenon.

  9. Evaluation of left ventricular function using digital subtraction angiography

    International Nuclear Information System (INIS)

    Kozuka, Takahiro; Ohta, Mitsushige

    1985-01-01

    To evaluate function of the left ventricle and myocardial perfusion images, digital subtraction angiography (DSA) was performed in 45 patients with ischemic heart disease. Validity of the technique was compared with data obtained from cine left ventriculogram in all patients and 201 T1 myocardial images in 20 patients. End-diastolic volume (EDV), end-systolic volume (ESV) and ejection fraction (EF) calculated from DSA were correlated closely with those from cine left ventriculogram (r = 0.92, r = 0.94 and r = 0.86, respectively). Regional contractility at the antero-lateral wall of the left ventricle, assessed by DSA, was also correlated well with cine left ventriculogram (r = 0.75). Evaluation of the inferior wall motion showed less correlation in both procedures (r = 0.68). Phase and amplitude analysis with the same technique with radionuclide cardiac angiography was successfully applied in left ventriculogram obtained by DSA. The procedure seems to be helpful for objective evaluation of the left ventricular wall motion. Myocardial perfusion image, obtained with modified Radtke's technique, showed good coincidence with 201 T1 images. Thus, DSA is applicable for evaluation of function of the left ventricle and myocardial perfusion in patients with ischemic heart disease. (author)

  10. The Lateralizing Asymmetry of Adrenal Adenomas

    Science.gov (United States)

    Hao, Meng; Lopez, Diana; Luque-Fernandez, Miguel Angel; Cote, Kathryn; Newfield, Jessica; Connors, Molly; Vaidya, Anand

    2018-01-01

    Abstract Context It is presumed that the incidence of adrenal adenomas is symmetric between the left and right adrenal gland; however, anecdotal observations suggest a potential lateralizing asymmetry. Objective To investigate the symmetry in detection of adrenal adenomas and relevance to patient care. Design Cross-sectional and longitudinal studies. Population and Setting One thousand three hundred seventy-six patients with abdominal computed tomography or magnetic resonance imaging demonstrating benign-appearing adrenal adenomas. Main Outcome Location and size of adrenal adenomas. Results Left-sided adenomas were discovered in 65% of patients, right-sided in 21%, and bilateral adenomas in 14%. Among unilateral adenomas, 75% were left-sided. Left-sided adenomas were more prevalent than right-sided adenomas in each size category except the largest: Adrenal adenomas are substantially more likely to be identified on the left adrenal than the right. This observation may be due to detection bias attributed to the location of the right adrenal, which may preclude identification of right-sided adenomas until they are substantially larger. These findings suggest the potential for an underrecognition of right-sided adenomas that may also impair the accurate detection of bilateral adrenal diseases. PMID:29644340

  11. Gait Patterns in Hemiplegic Children with Cerebral Palsy: Comparison of Right and Left Hemiplegia

    Science.gov (United States)

    Galli, Manuela; Cimolin, Veronica; Rigoldi, Chiara; Tenore, Nunzio; Albertini, Giorgio

    2010-01-01

    The aims of this study are to compare quantitatively the gait strategy of the right and left hemiplegic children with Cerebral Palsy (CP) using gait analysis. The gait strategy of 28 right hemiparetic CP (RHG) and 23 left hemiparetic CP (LHG) was compared using gait analysis (spatio-temporal and kinematic parameters) and considering the hemiplegic…

  12. High Frequency rTMS over the Left Parietal Lobule Increases Non-Word Reading Accuracy

    Science.gov (United States)

    Costanzo, Floriana; Menghini, Deny; Caltagirone, Carlo; Oliveri, Massimiliano; Vicari, Stefano

    2012-01-01

    Increasing evidence in the literature supports the usefulness of Transcranial Magnetic Stimulation (TMS) in studying reading processes. Two brain regions are primarily involved in phonological decoding: the left superior temporal gyrus (STG), which is associated with the auditory representation of spoken words, and the left inferior parietal lobe…

  13. Quantum Temporal Imaging

    OpenAIRE

    Tsang, Mankei; Psaltis, Demetri

    2006-01-01

    The concept of quantum temporal imaging is proposed to manipulate the temporal correlation of entangled photons. In particular, we show that time correlation and anticorrelation can be converted to each other using quantum temporal imaging.

  14. The anatomical location and laterality of orbital cavernous haemangiomas.

    Science.gov (United States)

    McNab, Alan A; Selva, Dinesh; Hardy, Thomas G; O'Donnell, Brett

    2014-10-01

    To determine the anatomical location and laterality of orbital cavernous haemangiomas (OCH). Retrospective case series. The records of 104 patients with OCH were analyzed. The anatomical location of each OCH defined by the location of a point at the centre of the lesion, and its laterality. There were 104 patients included in the study. No patient had more than one lesion. Sixteen (15.4%) were located in the anterior third of the orbit, 74 (71.2%) were in the middle third, and 14 (13.5%) in the posterior third. In the middle third, 10 of 74 (13.5%) were extraconal and 64 intraconal (86.5%), with 30 of 64 (46.9%) middle third intraconal lesions lying lateral to the optic nerve. Of 104 lesions, 56 (53.8%) were left sided, showing a trend towards a predilection for the left side (p = 0.065). If data from other published series which included data on laterality is added to our own data and analysed, 270 of 468 (57.7%) OCH occurred in the left orbit (p lateral to the optic nerve. This may reflect an origin of these lesions from the arterial side of the circulation, as there are more small arteries in the intraconal space lateral to the optic nerve than in other locations. A predilection for the left orbit remains unexplained.

  15. Laterally loaded masonry

    DEFF Research Database (Denmark)

    Raun Gottfredsen, F.

    In this thesis results from experiments on mortar joints and masonry as well as methods of calculation of strength and deformation of laterally loaded masonry are presented. The strength and deformation capacity of mortar joints have been determined from experiments involving a constant compressive...... stress and increasing shear. The results show a transition to pure friction as the cohesion is gradually destroyed. An interface model of a mortar joint that can take into account this aspect has been developed. Laterally loaded masonry panels have also been tested and it is found to be characteristic...... that laterally loaded masonry exhibits a non-linear load-displacement behaviour with some ductility....

  16. Cortical thickness in de novo patients with Parkinson disease and mild cognitive impairment with consideration of clinical phenotype and motor laterality.

    Science.gov (United States)

    Danti, S; Toschi, N; Diciotti, S; Tessa, C; Poletti, M; Del Dotto, P; Lucetti, C

    2015-12-01

    Parkinson's disease (PD) is a progressive neurodegenerative disorder with motor and non-motor symptoms, including cognitive deficits. Several magnetic resonance imaging approaches have been applied to investigate brain atrophy in PD. The aim of this study was to detect early structural cortical and subcortical changes in de novo PD whilst distinguishing cognitive status, clinical phenotype and motor laterality. Eighteen de novo PD with mild cognitive impairment (PD-MCI), 18 de novo PD without MCI (PD-NC) and 18 healthy control subjects were evaluated. In the PD-MCI group, nine were tremor dominant and nine were postural instability gait disorder (PIGD) phenotype; 11 had right-sided symptom dominance and seven had left-sided symptom dominance. FreeSurfer was used to measure cortical thickness/folding, subcortical structures and to study group differences as well as the association with clinical and neuropsychological data. Parkinson's disease with MCI showed regional thinning in the right frontal, right middle temporal areas and left insula compared to PD-NC. A reduction of the volume of the left and right thalamus and left hippocampus was found in PD-MCI compared to PD-NC. PD-MCI PIGD showed regional thinning in the right inferior parietal area compared to healthy controls. A decreased volume of the left thalamus was reported in PD-MCI with right-sided symptom dominance compared to PD-NC and PD-MCI with left-sided symptom dominance. When MCI was present, PD patients showed a fronto-temporo-parietal pattern of cortical thinning. This cortical pattern does not appear to be influenced by motor laterality, although one-sided symptom dominance may contribute to volumetric reduction of specific subcortical structures. © 2015 EAN.

  17. Possible evolutionary origins of cognitive brain lateralization.

    Science.gov (United States)

    Vallortigara, G; Rogers, L J; Bisazza, A

    1999-08-01

    Despite the substantial literature on the functional architecture of the asymmetries of the human brain, which has been accumulating for more than 130 years since Dax and Broca's early reports, the biological foundations of cerebral asymmetries are still poorly understood. Recent advances in comparative cognitive neurosciences have made available new animal models that have started to provide unexpected insights into the evolutionary origins and neuronal mechanisms of cerebral asymmetries. Animal model-systems, particularly those provided by the avian brain, highlight the interrelations of genetic, hormonal and environmental events to produce neural and behavioural asymmetries. Novel evidences showing that functional and structural lateralization of the brain is widespread among vertebrates (including fish, reptiles and amphibians) have accumulated rapidly. Perceptual asymmetries, in particular, seem to be ubiquitous in everyday behaviour of most species of animals with laterally placed eyes; in organisms with wider binocular overlap (e.g., amphibians), they appear to be retained for initial detection of stimuli in the extreme lateral fields. We speculate that adjustment of head position and eye movements may play a similar role in mammals with frontal vision as does the choice for right or left lateral visual fields in animals with laterally placed eyes. A first attempt to trace back the origins of brain asymmetry to early vertebrates is presented, based on the hypothesis that functional incompatibility between the logical demands associated with very basic cognitive functions is central to the phenomenon of cerebral lateralization.

  18. Using time-to-contact information to assess potential collision modulates both visual and temporal prediction networks

    Directory of Open Access Journals (Sweden)

    Jennifer T Coull

    2008-09-01

    Full Text Available Accurate estimates of the time-to-contact (TTC of approaching objects are crucial for survival. We used an ecologically valid driving simulation to compare and contrast the neural substrates of egocentric (head-on approach and allocentric (lateral approach TTC tasks in a fully factorial, event-related fMRI design. Compared to colour control tasks, both egocentric and allocentric TTC tasks activated left ventral premotor cortex/frontal operculum and inferior parietal cortex, the same areas that have previously been implicated in temporal attentional orienting. Despite differences in visual and cognitive demands, both TTC and temporal orienting paradigms encourage the use of temporally predictive information to guide behaviour, suggesting these areas may form a core network for temporal prediction. We also demonstrated that the temporal derivative of the perceptual index tau (tau-dot held predictive value for making collision judgements and varied inversely with activity in primary visual cortex (V1. Specifically, V1 activity increased with the increasing likelihood of reporting a collision, suggesting top-down attentional modulation of early visual processing areas as a function of subjective collision. Finally, egocentric viewpoints provoked a response bias for reporting collisions, rather than no-collisions, reflecting increased caution for head-on approaches. Associated increases in SMA activity suggest motor preparation mechanisms were engaged, despite the perceptual nature of the task.

  19. Surgical Management and Long-Term Seizure Outcome After Surgery for Temporal Lobe Epilepsy Associated with Cerebral Cavernous Malformations.

    Science.gov (United States)

    Yang, Peng-Fan; Pei, Jia-Sheng; Jia, Yan-Zeng; Lin, Qiao; Xiao, Hui; Zhang, Ting-Ting; Zhong, Zhong-Hui

    2018-02-01

    Operative strategies for cerebral cavernous malformation (CCM)-associated temporal lobe epilepsy and timing of surgical intervention continue to be debated. This study aimed to establish an algorithm to evaluate the efficacy of surgical intervention strategies, to maximize positive surgical outcomes and minimize postsurgical neurologic deficits. 47 patients having undergone operation for CCM-associated temporal lobe epilepsy were retrospectively reviewed. They had received a diagnostic series for seizure localization, including long-term video electroencephalography (vEEG), high-resolution magnetic resonance imaging (MRI), and positron emission tomography-computed tomography (PET-CT). In patients with mesial temporal lobe CCMs, the involved structures (amygdala, hippocampus, or parahippocampal gyrus) were resected in addition to the lesions. Patients with neocortical epileptogenic CCM underwent extended lesionectomy guided by intraoperative electrocorticography; further performance of amygdalohippocampectomy depended on the extent of hippocampal epileptogenicity. The study cohort contained 28 patients with drug-resistant epilepsy (DRE), 12 with chronic epilepsy (CE), and 7 with sporadic seizure (SS). Normal temporal lobe metabolism was seen in 7/7 patients of the SS group. Hypometabolism was found in all patients with chronic disease except for those with posterior inferior and middle temporal gyrus cavernous malformations (CMs). Of the 31 patients with superficial neocortical CCM, 7 had normal PET without hippocampal sclerosis, 14 had ipsilateral temporal lobe hypometabolism without hippocampal sclerosis, and 10 had obvious hippocampal sclerosis and hypometabolism. Seizure freedom in DRE, CE, and SS was 82.1%, 75%, and 100%, respectively. A significant difference was found between lesion laterality and postoperative seizure control; the rate was lower in left-sided cases because of less aggressive resection. Our study demonstrates that the data from the

  20. PCR, exit stage left ...

    CERN Multimedia

    2004-01-01

    The Prevessin Control Room during LEP's start up in 1989. The Prévessin Control Room (PCR) was recently engulfed in a wave of nostalgia. The PCR, scene of some of the greatest moments in CERN's history, is being dismantled to prepare for a complete overhaul. In February 2006, a new combined control centre for all the accelerators will open its doors on the same site, together with a new building currently under construction (see Bulletin issue 27/2004 of 28 June 2004). This marks the end of an important chapter in CERN's history. The Prévessin Control Room saw its first momentous event 28 years ago when the 400 GeV beam for the SPS was commissioned in the presence of Project Leader John Adams. It was also here that the first proton-antiproton collisions were observed, in 1981. Eight years later, in 1989, operators and directors alike jumped for joy at the announcement of the first electron-positron collisions at the start up of LEP, the biggest accelerator in the world. Today the 80 terminals and PCs have b...