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Right Hemisphere (right + hemisphere)
Selected AbstractsOutcome of severe unilateral cerebellar hypoplasiaDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2010ANDREA PORETTI Aim, Complete or subtotal absence of one cerebellar hemisphere is exceptional; only single cases have been described. We aimed to assess the long-term outcome in children with severe unilateral cerebellar hypoplasia (UCH). Method, As part of a retrospective study we describe neuroimaging features, clinical findings, and cognitive outcomes of seven children with UCH (five males, two females; age at first magnetic resonance imaging [MRI]: median 1y 3mo, range 9d,8y 10mo; age at latest follow-up: median 6y 6mo, range 2y 3mo,14y 11mo). Results, One child had abnormalities on prenatal MRI at 21 weeks' gestation. The left cerebellar hemisphere was affected in five children, and the right hemisphere in two children. The vermis was involved in five children. The volume of the posterior fossa was variable. At the latest follow-up, neurological findings included truncal ataxia and muscular hypotonia in five children, limb ataxia in three patients, and head nodding in two patients. Three children had learning disability*, five had speech and language disorders, and one had a severe behavioural disorder. Interpretation, Severe UCH is a residual change after a disruptive prenatal cerebellar insult, most likely haemorrhagic. The outcome is variable, ranging from almost normal development to marked developmental impairment. Ataxia is a frequent but not a leading sign. It seems that involvement of the cerebellar vermis is often, but not consistently, associated with a poorer cognitive outcome, whereas an intact vermis is associated with normal outcome and no truncal ataxia. [source] The role of epilepsy in early language development in a child with a congenital lesion in the right hemisphereDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 11 2008C Mayor-Dubois MA Early epilepsy is known to worsen the developmental prognosis of young children with a congenital focal brain lesion, but its direct role is often very difficult to delineate from the other variables. This requires prolonged periods of follow-up with simultaneous serial electrophysiological and developmental assessments which are rarely obtained. We studied a male infant with a right prenatal infarct in the territory of the right middle cerebral artery resulting in a left spastic hemiparesis, and an epileptic disorder (infantile spasms with transient right hemihypsarrhythmia and focal seizures) from the age of 7 months until the age of 4 years. Pregnancy and delivery were normal. A dissociated delay of early language acquisition affecting mainly comprehension without any autistic features was documented. This delay was much more severe than usually expected in children with early focal lesions, and its evolution, with catch-up to normal, was correlated with the active phase of the epilepsy. We postulate that the epilepsy specifically amplified a pattern of delayed language emergence, mainly affecting lexical comprehension, reported in children with early right hemisphere damage. [source] Localizing and Lateralizing Value of Behavioral Change in Childhood Partial SeizuresEPILEPSIA, Issue 1 2007András Fogarasi Summary:,Objective: To describe clinical characteristics as well as localizing and lateralizing value of behavioral change (BC) at the onset of childhood seizures. Methods: Five hundred forty-one videotaped seizures of 109 consecutive patients ,12 years with partial epilepsy and postoperatively seizure-free outcome were analyzed. Behavioral change (the first clinical feature of a certain seizure with a sudden change in the child's behavior) was evaluated by two independent investigators. Results: Thirty-three (30%) patients showed BC at least once during their seizures. Behavioral changes appeared in arrestive form in 19 and with affective activities in 18 children; four patients produced both kinds of BCs, separately. Arrest-type BC happened in 16 of 50 children with right- and 3 of 59 patients with left-sided seizure onset zone (p < 0.001). Affective-type BC was observed in 17 of 67 temporal lobe epilepsy patients while it happened in only 1 of 42 children with extratemporal lobe epilepsy (p = 0.001). Conclusions: Arrest-type BC lateralizes to the right hemisphere, while affective-type BC localizes to the temporal lobe in childhood partial seizures. Type of BCs can add important information to the presurgical evaluation of young children with refractory partial epilepsy. [source] fMRI Lateralization of Expressive Language in Children with Cerebral LesionsEPILEPSIA, Issue 6 2006Dianne P. Anderson Summary:,Purpose: Lateralization of language function is crucial to the planning of surgery in children with frontal or temporal lobe lesions. We examined the utility of functional magnetic resonance imaging (fMRI) as a determinant of lateralization of expressive language in children with cerebral lesions. Methods: fMRI language lateralization was attempted in 35 children (29 with epilepsy) aged 8,18 years with frontal or temporal lobe lesions (28 left hemisphere, five right hemisphere, two bilateral). Axial and coronal fMRI scans through the frontal and temporal lobes were acquired at 1.5 Tesla by using a block-design, covert word-generation paradigm. Activation maps were lateralized by blinded visual inspection and quantitative asymmetry indices (hemispheric and inferior frontal regions of interest, at p < 0.001 uncorrected and p < 0.05 Bonferroni corrected). Results: Thirty children showed significant activation in the inferior frontal gyrus. Lateralization by visual inspection was left in 21, right in six, and bilateral in three, and concordant with hemispheric and inferior frontal quantitative lateralization in 93% of cases. Developmental tumors and dysplasias involving the inferior left frontal lobe had activation overlying or abutting the lesion in five of six cases. fMRI language lateralization was corroborated in six children by frontal cortex stimulation or intracarotid amytal testing and indirectly supported by aphasiology in a further six cases. In two children, fMRI language lateralization was bilateral, and corroborative methods of language lateralization were left. Neither lesion lateralization, patient handedness, nor developmental versus acquired nature of the lesion was associated with language lateralization. Involvement of the left inferior or middle frontal gyri increased the likelihood of atypical language lateralization. Conclusions: fMRI lateralizes language in children with cerebral lesions, although caution is needed in interpretation of individual results. [source] Focal Semiologic and Electroencephalographic Features in Patients with Juvenile Myoclonic EpilepsyEPILEPSIA, Issue 10 2005Naotaka Usui Summary:,Purpose: A few reports have described focal electroencephalographic or clinical features or both of juvenile myoclonic epilepsy (JME), but without video-EEG documentation. We examined focal clinical and EEG features in patients with JME who underwent video-EEG monitoring. Methods: Twenty-six patients (nine males and 17 females) who had seizures recorded during video-EEG monitoring were included. Age at seizure onset was 0 to 22 years (mean, 12.3 years), and age at monitoring was 12 to 44 years (mean, 26.5 years). In one patient with left parietooccipital epilepsy, primary generalized tonic,clonic seizures developed after resection of the parietal tumor. Two patients had both temporal lobe epilepsy and JME. Videotaped seizures in each patient were analyzed. Interictal and ictal EEG also were analyzed for any focal features. Results: Focal semiologic features were observed in 12 (46%) of 26 patients. Six patients had focal myoclonic seizures, and two had Figure 4 sign: one with version to the left, and another had left version followed by Figure 4 sign, and left arm clonic seizure. Their ictal EEGs were generalized at onset but with a lateralized evolution over the right hemisphere. The patient who had both JME and left parietooccipital epilepsy, right arm clonic seizure, and Figure 4 sign was seen during a generalized EEG seizure. Interictally, one patient had temporal sharp waves, and another had run of spikes in the right frontal region. Conclusions: Fourteen (54%) of 26 patients with JME exhibited focal semiologic or electroencephalographic features or both. Video-EEG was essential in reaching a correct diagnosis and choosing an appropriate antiepileptic drug regimen. [source] Wada Memory Performance Predicts Seizure Outcome after Epilepsy Surgery in ChildrenEPILEPSIA, Issue 7 2003Gregory P. Lee Summary: Purpose: Wada memory asymmetries were examined in children from four comprehensive epilepsy surgery centers who subsequently underwent epilepsy surgery to determine whether Wada memory performance could predict degree of seizure relief in children. Methods: One hundred fifty-six children (between ages 5 and 16 years) with intractable epilepsy underwent Wada testing before resective epilepsy surgery (93 within the left hemisphere, and 63 within the right hemisphere). Memory stimuli were presented soon after intracarotid amobarbital injection, and recognition memory for the items was assessed after return to neurologic baseline. Eighty-eight children underwent unilateral temporal lobe resection, and 68 had extratemporal lobe resections. One hundred four (67%) children were seizure free (Engel class I), and 52 (33%) were not seizure free (Engel classes II,IV) at follow-up (mean follow-up interval, 2.3 years). Results: Seizure-free children recalled 19.3% more Wada memory items after ipsilateral injection than did non,seizure-free children (p = 0.008). If analysis was restricted to youngsters with temporal lobectomies (TLs), seizure-free children recalled 27.7% more items after ipsilateral injection than did non,seizure-free TL children (p = 0.004). With regard to individual patient prediction, 75% of children who had memory score asymmetries consistent with the seizure focus were seizure free. In contrast, only 56% of children whose memory score asymmetries were inconsistent with the seizure focus were seizure free (p = 0.01). Conclusions: Results suggest that Wada memory performance asymmetries are related to the degree of seizure relief after epilepsy surgery in children and adolescents. [source] The neural networks of musicEUROPEAN JOURNAL OF NEUROLOGY, Issue 5 2002E. Baeck Recent neuropsychological, transcranial Doppler sonographic, positron emission tomographic and functional nuclear magnetic resonance studies have indicated that musical perception is not dependent on the right hemisphere but on neural networks corresponding to the fundamental components of music in both hemispheres. In the brain there is no centre for music. Musicians have cerebral characteristics, anatomical as well as functional, which are correlated with the age at which they began their musical studies. This argues for cortical reorganization as a result of musical training. Whether these characteristics are to be ascribed to cortical plasticity alone, or to an innate structural property, or to both, remains an open question, however. Investigation of chromosomal defects, biochemical abnormalities and morphological features of congenital and degenerative brain diseases can provide further insight into the cerebral substrate of musicality. [source] Cognitive response control in writer's crampEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2001D. Berg Disturbances of the motor and sensory system as well as an alteration of the preparation of movements have been reported to play a role in the pathogenesis of dystonias. However, it is unclear whether higher aspects of cortical , like cognitive , functions are also involved. Recently, the NoGo-anteriorization (NGA) elicited with a visual continuous performance test (CPT) during recording of a 21-channel electroencephalogram has been proposed as an electrophysiological standard-index for cognitive response control. The NGA consists of a more anterior location of the positive area of the brain electrical field associated with the inhibition (NoGo-condition) compared with that of the execution (Go-condition) of a prepared motor response in the CPT. This response control paradigm was applied in 16 patients with writer's cramp (WC) and 14 age matched healthy controls. Topographical analysis of the associated event-related potentials revealed a significant (P < 0.05) NGA effect for both patients and controls. Moreover, patients with WC showed a significantly higher global field power value (P < 0.05) in the Go-condition and a significantly higher difference-amplitude (P < 0.05) in the NoGo-condition. A source location analysis with the low resolution electromagnetic tomography (LORETA) method demonstrated a hypoactivity for the Go-condition in the parietal cortex of the right hemisphere and a hyperactivity in the NoGo-condition in the left parietal cortex in patients with WC compared with healthy controls. These results indicate an altered response control in patients with WC in widespread cortical brain areas and therefore support the hypothesis that the pathogenesis of WC is not restricted to a pure sensory-motor dysfunction. [source] Passive avoidance training decreases synapse density in the hippocampus of the domestic chickEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 4 2006A. M. Nikolakopoulou Abstract The bird hippocampus (Hp), although lacking the cellular lamination of the mammalian Hp, possesses comparable roles in spatial orientation and is implicated in passive avoidance learning. As in rodents it can be divided into dorsal and ventral regions based on immunocytochemical, tracing and electrophysiological studies. To study the effects of passive avoidance learning on synapse morphometry in the Hp, spine and shaft synapse densities of 1-day-old domestic chicks were determined in dorsal and ventral Hp of each hemisphere by electron microscopy, 6 and 24 h following training to avoid pecking at a bead coated with a bitter-tasting substance, methyl anthranilate (MeA). The density of asymmetric spine and shaft synapses in MeA-trained birds at 6 h post-training was significantly lower in the dorsal and ventral Hp of the right hemisphere relative to control (untrained) chicks, but by 24 h this difference was absent. A hemispheric asymmetry was apparent in the ventral Hp where the water-trained group showed enhanced shaft and spine synapse density in the left hemisphere, whilst in the MeA-trained group only asymmetric shaft synapses follow the same pattern in relation to the right hemisphere. There were no differences in asymmetric shaft synapses in the dorsal Hp at 6 h post-training, but at 24 h post-training there was a reduction in the density of shaft synapses in the right hemisphere in MeA compared with control birds. These data are discussed in relation to the pruning effects of stress and learning on synapse density in chick Hp. [source] Right-hemisphere motor facilitation by self-descriptive personality-trait wordsEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2005Istvan Molnar-Szakacs Abstract The emergent picture from the literature on the processing of self-related information suggests that in addition to the neural mechanisms involved in recognizing one's own face, there may also be neural representations of the self that are modality independent and favour the right hemisphere. We used focal, single-pulse transcranial magnetic stimulation in human subjects to assess cortical excitability during covert reading of self-descriptive personality-trait words. We hypothesized that the right hemisphere would show a greater overall facilitation to personality-trait words than the left hemisphere. Overall, personality-trait words led to significantly greater motor facilitation in the right hemisphere than in the left hemisphere. In addition, words rated as ,never' self-characteristic yielded significant right hemisphere facilitation, and words rated as ,always' self-characteristic showed a similar trend. The results are discussed in terms of the notion that the right hemisphere plays a dominant role in both self-relevant processing and the processing of affective stimuli. [source] Tonotopic representation of missing fundamental complex sounds in the human auditory cortexEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 2 2003Takako Fujioka Abstract The N1m component of the auditory evoked magnetic field in response to tones and complex sounds was examined in order to clarify whether the tonotopic representation in the human secondary auditory cortex is based on perceived pitch or the physical frequency spectrum of the sound. The investigated stimulus parameters were the fundamental frequencies (F0 = 250, 500 and 1000 Hz), the spectral composition of the higher harmonics of the missing fundamental sounds (2nd to 5th, 6th to 9th and 10th to 13th harmonic) and the frequencies of pure tones corresponding to F0 and to the lowest component of each complex sound. Tonotopic gradients showed that high frequencies were more medially located than low frequencies for the pure tones and for the centre frequency of the complex tones. Furthermore, in the superior,inferior direction, the tonotopic gradients were different between pure tones and complex sounds. The results were interpreted as reflecting different processing in the auditory cortex for pure tones and complex sounds. This hypothesis was supported by the result of evoked responses to complex sounds having longer latencies. A more pronounced tonotopic representation in the right hemisphere gave evidence for right hemispheric dominance in spectral processing. [source] Direction of cross-modal information transfer affects human brain activation: a PET studyEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 1 2002Ryuta Kawashima Abstract The purpose of this study was to determine the functional organization of the human brain involved in cross-modal discrimination between tactile and visual information. Regional cerebral blood flow was measured by positron emission tomography in nine right-handed volunteers during four discrimination tasks; tactile,tactile (TT), tactile,visual (TV), visual,tactile (VT), and visual,visual (VV). The subjects were asked either to look at digital cylinders of different diameters or to grasp the digital cylinders with the thumb and index finger of the right hand using haptic interfaces. Compared with the motor control task in which the subjects looked at and grasped cylinders of the same diameter, the right lateral prefrontal cortex and the right inferior parietal lobule were activated in all the four discrimination tasks. In addition, the dorsal premotor cortex, the ventral premotor cortex, and the inferior temporal cortex of the right hemisphere were activated during VT but not during TV. Our results suggest that the human brain mechanisms underlying cross-modal discrimination have two different pathways depending on the temporal order in which stimuli are presented. [source] Selective activation of the ventrolateral prefrontal cortex in the human brain during active retrieval processingEUROPEAN JOURNAL OF NEUROSCIENCE, Issue 7 2001Genevičve Cadoret Abstract The present study examined the role of the prefrontal cortex in retrieval processing using functional magnetic resonance imaging in human subjects. Ten healthy subjects were scanned while they performed a task that required retrieval of specific aspects of visual information. In order to examine brain activity specifically associated with retrieval, we designed a task that had retrieval and control conditions that were perfectly matched in terms of depth of encoding, decision making and postretrieval monitoring and differed only in terms of whether retrieval was required. In the retrieval condition, based on an instructional cue, the subjects had to retrieve either the particular stimulus that was previously presented or its location. In the control condition, the cue did not instruct retrieval but shared with the instructional cues the function of alerting the subjects of the impending test phase. The comparison of activity between the retrieval and control conditions demonstrated a significant and selective increase in activity related to retrieval processes within the ventrolateral prefrontal cortical region, more specifically within area 47/12. These activity increases were bilateral but stronger in the right hemisphere. The present study by strictly controlling the level of encoding, postretrieval monitoring, and decision making has demonstrated a specific increase in the ventrolateral prefrontal region that could be clearly related to active retrieval processing, i.e. the active selection of particular stored visual representations. [source] Dissociable neural responses in the hippocampus to the retrieval of facial identity and emotion: An event-related fMRI studyHIPPOCAMPUS, Issue 4 2003Tetsuya Iidaka Abstract In studies with brain-damaged patients and experimental animals, the medial temporal lobe, including the hippocampus and parahippocampal gyrus, has been found to play a critical role in establishing declarative or episodic memory. We measured the neural response in these structures, using event-related functional magnetic resonance imaging, while six healthy subjects performed the retrieval task for facial identity and emotion, respectively. Under the identity condition, the subjects participated in a yes/no recognition test for neutral faces learned before the scanning. Under the emotion condition, the subjects learned the faces with positive or negative expression and retrieved their expressions from neutral cue faces. The results showed that the left hippocampus is primarily involved in the identification of learned faces, and that the adjacent parahippocampal gyrus responds more to target than to distracter events. These results indicate a specific engagement of the left hippocampal regions in conscious recollection and identification of physiognomic facial features. The activity in the right hippocampus increased under both the identity and emotion conditions. The present results may relate with the functional model of face recognition in which the left hemisphere contributes to the processing of detailed features and the right hemisphere is efficient in the processing of global features. Hippocampus 2003;13:429,436. © 2003 Wiley-Liss, Inc. [source] The lateral-occipital and the inferior-frontal cortex play different roles during the naming of visually presented objectsHUMAN BRAIN MAPPING, Issue 12 2009Philippe A. Chouinard Abstract We reasoned that if an area is devoted to processing only the visual features of objects, then transcranial magnetic stimulation (TMS) applied to this area in either hemisphere would affect the naming of objects presented in contralateral but not ipsilateral space. In contrast, if an area is involved in language, then one might expect to see effects of TMS when applied over the left but not the right hemisphere, regardless whether objects are in contralateral or ipsilateral space. Our experiments reveal two important findings. First, TMS delivered to the lateral-occipital complex (LOC), a visual-form area, affected the naming of objects presented in contralateral but not ipsilateral space, independent of which hemisphere was stimulated. In two additional experiments, when participants named the color of objects or made judgments about the size of stimuli as shown physically on a computer screen, TMS over the contralateral LOC did not affect color naming but did affect the participants' ability to make size judgments. Second, TMS delivered to the left but not the right posterior inferior-frontal gyrus (pIFG) affected the naming of objects irrespective of whether objects were presented in contralateral or ipsilateral space. In a separate experiment, when participants were asked to either read or categorize words, TMS over the left but not the right pIFG affected word categorization but not word reading. On the basis of these findings, we propose that when people name visually-presented objects, LOC processes the visual form of objects while the left pIFG processes the semantics of objects. Hum Brain Mapp, 2009. © 2009 Wiley-Liss, Inc. [source] Cortical mapping of naming errors in aphasia,HUMAN BRAIN MAPPING, Issue 8 2009Julius Fridriksson Abstract Persons with aphasia vary greatly with regard to clinical profile; yet, they all share one common feature,anomia,an impairment in naming common objects. Previous research has demonstrated that particular naming errors are associated with specific left hemisphere lesions. However, we know very little about the cortical activity in the preserved brain areas that is associated with aphasic speech errors. Utilizing functional magnetic resonance imaging (fMRI), we show for the first time that specific speech errors are associated with common cortical activity in different types and severities of aphasia. Specifically, productions of phonemic errors recruited the left posterior perilesional occipital and temporal lobe areas. A similar pattern of activity was associated with semantic errors, albeit in the right hemisphere. This study does not discount variability in cortical activity following left hemisphere stroke; rather, it highlights commonalities in brain modulation in a population of patients with a common diagnosis but vastly different clinical profiles. Hum Brain Mapp 2009. © 2009 Wiley-Liss, Inc. [source] fMRI evidence for multisensory recruitment associated with rapid eye movements during sleepHUMAN BRAIN MAPPING, Issue 5 2009Charles Chong-Hwa Hong Abstract We studied the neural correlates of rapid eye movement during sleep (REM) by timing REMs from video recording and using rapid event-related functional MRI. Consistent with the hypothesis that REMs share the brain systems and mechanisms with waking eye movements and are visually-targeted saccades, we found REM-locked activation in the primary visual cortex, thalamic reticular nucleus (TRN), ,visual claustrum', retrosplenial cortex (RSC, only on the right hemisphere), fusiform gyrus, anterior cingulate cortex, and the oculomotor circuit that controls awake saccadic eye movements (and subserves awake visuospatial attention). Unexpectedly, robust activation also occurred in non-visual sensory cortices, motor cortex, language areas, and the ascending reticular activating system, including basal forebrain, the major source of cholinergic input to the entire cortex. REM-associated activation of these areas, especially non-visual primary sensory cortices, TRN and claustrum, parallels findings from waking studies on the interactions between multiple sensory data, and their ,binding' into a unified percept, suggesting that these mechanisms are also shared in waking and dreaming and that the sharing goes beyond the expected visual scanning mechanisms. Surprisingly, REMs were associated with a decrease in signal in specific periventricular subregions, matching the distribution of the serotonergic supraependymal plexus. REMs might serve as a useful task-free probe into major brain systems for functional brain imaging. Hum Brain Mapp 2009. © 2008 Wiley-Liss, Inc. [source] Brain responses to auditory and visual stimulus offset: Shared representations of temporal edgesHUMAN BRAIN MAPPING, Issue 3 2009Marcus Herdener Abstract Edges are crucial for the formation of coherent objects from sequential sensory inputs within a single modality. Moreover, temporally coincident boundaries of perceptual objects across different sensory modalities facilitate crossmodal integration. Here, we used functional magnetic resonance imaging in order to examine the neural basis of temporal edge detection across modalities. Onsets of sensory inputs are not only related to the detection of an edge but also to the processing of novel sensory inputs. Thus, we used transitions from input to rest (offsets) as convenient stimuli for studying the neural underpinnings of visual and acoustic edge detection per se. We found, besides modality-specific patterns, shared visual and auditory offset-related activity in the superior temporal sulcus and insula of the right hemisphere. Our data suggest that right hemispheric regions known to be involved in multisensory processing are crucial for detection of edges in the temporal domain across both visual and auditory modalities. This operation is likely to facilitate cross-modal object feature binding based on temporal coincidence. Hum Brain Mapp, 2009. © 2008 Wiley-Liss, Inc. [source] Effects of transdermal nicotine on lateralized identification and memory interferenceHUMAN PSYCHOPHARMACOLOGY: CLINICAL AND EXPERIMENTAL, Issue 5 2003F. Joseph McClernon Abstract It has been proposed that nicotine may enhance performance on tasks requiring primarily left hemisphere (LH) resources while impairing right hemisphere (RH)-based performance. However, this hypothesis has not been directly tested using a lateralized cognitive task. The effects of transdermal nicotine administration on lateralized consonant identification and memory interference were examined in dependent smokers and never-smokers. In a double-blind placebo-controlled design, smokers (n,=,24) and never-smokers (n,=,24) were assigned to receive a nicotine or placebo patch. Subjects completed a lateralized letter identification task that required them to identify strings of three consonants presented in the left or right visual field while keeping a word in memory. A distinct right-visual-field (RVF) advantage was observed for consonant identification, but this effect was unaltered by nicotine or smoking status. However, nicotine decreased word memory errors on trials where consonants were presented in the RVF and increased errors on LVF trials. Nicotine may enhance LH-based cognitive performance by increasing LH cognitive resources or by reducing the influence of RVF distracting stimuli. These findings are consistent with a model of the lateralized effects of nicotine on cognitive performance. Copyright © 2003 John Wiley & Sons, Ltd. [source] Brain, mind, and dyadic change processesJOURNAL OF CLINICAL PSYCHOLOGY, Issue 5 2006Robert J. Neborsky For many individuals attachment trauma is at the core of psychoneurosis and personality disorder. Combining theoretical aspects of psychodynamic therapy, developmental neuroscience, and attachment styles provides a useful framework for intensifying emotion and accelerating the course of treatment. A bihemispheric model is considered. The model addresses the challenge in treating the implicit trauma, which resides in the right hemisphere. This is achieved without resorting to interpretation, which is largely a left hemispheric process. The article presents a patient who benefits from a brief emotionally based psychotherapy that was completed after a course of a 20-year psychoanalysis. © 2006 Wiley Periodicals, Inc. J Clin Psychol: In Session 62: 523,538, 2006. [source] Rapid Upregulation of Aromatase mRNA and Protein Following Neural Injury in the Zebra Finch (Taeniopygia guttata)JOURNAL OF NEUROENDOCRINOLOGY, Issue 4 2001R. Scott Peterson Abstract The expression of aromatase (oestrogen synthase) within the vertebrate central nervous system (CNS) is key in the provision of local oestrogens to neural circuits. Aromatase expression appears to be exclusively neuronal under normal conditions. However, some in vitro studies suggest the presence of astrocytic aromatase in songbirds and mammals. Recently, aromatase in reactive astrocytes has been demonstrated in response to neural injury in the mammalian CNS. Since the glial aromatase expression first documented in cultures of the songbird telencephalon may reflect processes similar to those in response to mammalian neural injury, we investigated whether injury alters the pattern of aromatase-expression in the zebra finch, a species with very high levels of forebrain aromatase expression. Adult males received a penetrating neural injury to the right hemisphere and were killed either 24 or 72 h later. Controls were anaesthetized and otherwise unmanipulated. We determined the expression of aromatase mRNA and protein using in situ hybridization and immunocytochemistry, respectively. Both the transcription and translation of aromatase is dramatically upregulated around the lesion site in response to neural injury in the zebra finch forebrain. This effect is robust and rapid, occurring within 24 h of the injury itself. Cells that upregulate aromatase appear to be reactive astrocytes based upon morphology. The hemisphere contralateral to the injury and both hemispheres in control birds showed the normal, exclusively neuronal pattern of aromatase expression. The upregulation of aromatase in astrocytes may provide high levels of oestrogen available to modulate processes such as CNS repair. Injury-induced upregulation of astrocytic aromatase may be a general characteristic of the injured vertebrate brain. [source] Moyamoya-disease-related ischemic stroke in the postpartum periodJOURNAL OF OBSTETRICS AND GYNAECOLOGY RESEARCH (ELECTRONIC), Issue 5 2009Kei Miyakoshi Abstract Stroke during pregnancy or the puerperium is an extremely rare yet serious cause of perinatal morbidity and mortality. Moyamoya disease, a cerebrovascular occlusive pathology with a female predominance, may become symptomatic for the first time in association with pregnancy. A 36-year-old woman with postpartum pre-eclampsia suddenly developed hemiparesis in the left arm with dysarthria after the initiation of antihypertensive measures. Cranial magnetic resonance imaging and angiography revealed acute ischemic lesions in the right hemisphere along with the steno-occlusive lesions of bilateral terminal portions of the internal carotid artery, indicating Moyamoya disease. With anti-platelet medication, the patient recovered gradually and was diagnosed as having Moyamoya disease using conventional angiography 3 months postpartum. In this case, the fluctuations in blood pressure in association with pre-eclampsia appear to have exacerbated the clinical symptoms of Moyamoya disease. As such, Moyamoya disease should be considered as an underlying disease of ischemic stroke associated with pregnancy. [source] Frontal White Matter and Cingulum Diffusion Tensor Imaging Deficits in AlcoholismALCOHOLISM, Issue 6 2008Gordon J. Harris Background:, Alcoholism-related deficits in cognition and emotion point toward frontal and limbic dysfunction, particularly in the right hemisphere. Prefrontal and anterior cingulate cortices are involved in cognitive and emotional functions and play critical roles in the oversight of the limbic reward system. In the present study, we examined the integrity of white matter tracts that are critical to frontal and limbic connectivity. Methods:, Diffusion tensor magnetic resonance imaging (DT-MRI) was used to assess functional anisotropy (FA), a measure of white matter integrity, in 15 abstinent long-term chronic alcoholic and 15 demographically equivalent control men. Voxel-based and region-based analyses of group FA differences were applied to these scans. Results:, Alcoholic subjects had diminished frontal lobe FA in the right superior longitudinal fascicles II and III, orbitofrontal cortex white matter, and cingulum bundle, but not in corresponding left hemisphere regions. These right frontal and cingulum white matter regional FA measures provided 97% correct group discrimination. Working Memory scores positively correlated with superior longitudinal fascicle III FA measures in control subjects only. Conclusions:, The findings demonstrate white matter microstructure deficits in abstinent alcoholic men in several right hemisphere tracts connecting prefrontal and limbic systems. These white matter deficits may contribute to underlying dysfunction in memory, emotion, and reward response in alcoholism. [source] Working memory in posttraumatic stress disorder,an event-related potential studyJOURNAL OF TRAUMATIC STRESS, Issue 2 2001Cherrie Galletly Abstract This study examined ERP topography during the updating and the utilization of working memory in subjects with PTSD. Event-related potentials of 18 participants with PTSD and 18 controls were recorded from 32 scalp electrodes during an auditory target detection task requiring the constant updating of target identity. Midline N2 and P3 abnormalities previously noted in PTSD during target detection were replicated. Scalp topographic data revealed sustained reduction in activity over the right hemisphere during working memory updating. Executive processes were associated with brief but widespread right hemisphere reductions during the P3, followed by sustained, bilateral reduction frontally. This study identifies an abnormal pattern of cortical network function during both the updating and use of working memory in PTSD. [source] Discourse Impairments Following Right Hemisphere Brain Damage: A Critical ReviewLINGUISTICS & LANGUAGE COMPASS (ELECTRONIC), Issue 6 2008Clinton L. Johns Right hemisphere brain damage (RHD) rarely causes aphasias marked by clear and widespread failures of comprehension or extreme difficulty producing fluent speech. Nonetheless, subtle language comprehension deficits can occur following unilateral RHD. In this article, we review the empirical record on discourse function following right hemisphere damage, as well as relevant work on non-brain damaged individuals that focuses on right hemisphere function. The review is divided into four sections that focus on discourse processing, inferencing, humor, and non-literal language. While the exact role that the right hemisphere plays in language processing, and the exact way that the two cerebral hemispheres coordinate their linguistic processes are still open to debate, our review suggests that the right hemisphere plays a critical role in managing inferred or implied information by maintaining relevant information and/or suppressing irrelevant information. Deficits in one or both of these mechanisms may account for discourse deficits following RHD. [source] Botulinum toxin treatment of facial myoclonus in suspected Rasmussen encephalitisMOVEMENT DISORDERS, Issue 9 2006Nina Browner MD Abstract Patients with Rasmussen encephalitis (RE) may develop a variety of involuntary movements. We report a 26-year-old woman who presented with a 3-year history of progressive, continuous myoclonus of the left side of the face and left arm as well as left spastic hemiparesis. Magnetic resonance imaging of the brain showed right hemisphere and basal ganglia atrophy, and 24-hour electroencephalogram demonstrated diffuse slowing with random sharp waves in both hemispheres. An 18-fluoro-deoxy-glucose positron emission tomography scan indicated hypometabolism of the right cerebral hemisphere, including basal ganglia and thalamus. We successfully treated her myoclonus with injections of botulinum toxin A into the left zygomaticus muscle. © 2006 Movement Disorder Society [source] Practice and endpoint accuracy with the left and right hands of old adults: The right-hemisphere aging modelMUSCLE AND NERVE, Issue 3 2008Brach Poston PhD Abstract The purpose of the study was to quantify the aging-related differences in endpoint accuracy during isometric contractions of the left and right hands based on the prediction that declines in motor performance with aging may be greater for muscles controlled by the right hemisphere. Twelve young (6 men, 25 ± 5 years) and 12 old (6 men, 76 ± 6 years) adults performed a task that involved matching the peak of a force,time trajectory to a target. The old adults were less accurate than the young men and exhibited greater endpoint error with the left hand than the right hand on day 1, but not on days 2 and 3. Although electromyographic amplitude was similar between hands, old adults exhibited greater timing variability. These findings indicate that given sufficient practice there was no difference in endpoint accuracy between the left and right hands of old adults, which is not consistent with the prediction of an asymmetrical decline in motor performance by the right-hemisphere aging model. Conversely, an inability by an old adult to achieve similar accuracy with both hands during such tasks likely indicates an underlying motor impairment. Muscle Nerve, 2007 [source] Mechanisms of face perception in humans: A magneto- and electro-encephalographic studyNEUROPATHOLOGY, Issue 1 2005Shoko Watanabe We have been studying the underlying mechanisms of face perception in humans using magneto- (MEG) and electro-encephalography (EEG) including (1) perception by viewing the static face, (2) differences in perception by viewing the eyes and whole face, (3) the face inversion effect, (4) the effect of gaze direction, (5) perception of eye motion, (6) perception of mouth motion, and (7) the interaction between auditory and visual stimuli related to the vowel sounds. In this review article, we mainly summarize our results obtained on 3, 5, and 6 above. With the presentation of both upright and inverted unfamiliar faces, the inferior temporal cortex (IT) centered on the fusiform gyrus, and the lateral temporal cortex (LT) near the superior temporal sulcus were activated simultaneously, but independently, between 140 and 200 ms post-stimulus. The right hemisphere IT and LT were both active in all subjects, and those in the left hemisphere in half of the subjects. Latencies with inverted faces relative to those with upright faces were longer in the right hemisphere, and shorter in the left hemisphere. Since the activated regions under upright and those under inverted face stimuli did not show a significant difference, we consider that differences in processing upright versus inverted faces are attributable to temporal processing differences rather than to processing of information by different brain regions. When viewing the motion of the mouth and eyes, a large clear MEG component, 1M (mean peak latency of approximately 160 ms), was elicited to both mouth and eye movement, and was generated mainly in the occipito-temporal border, at human MT/V5. The 1M to mouth movement and the 1M to eye movement showed no significant difference in amplitude or generator location. Therefore, our results indicate that human MT/V5 is active in the perception of both mouth and eye motion, and that the perception of movement of facial parts is probably processed similarly. [source] Analysis of magnetic source localization of P300 using the multiple signal classification algorithmPSYCHIATRY AND CLINICAL NEUROSCIENCES, Issue 6 2006TETSUO UOHASHI md Abstract, The authors studied the localization of P300 magnetic sources using the multiple signal classification (MUSIC) algorithm. Six healthy subjects (aged 24,34 years old) were investigated with 148-channel whole-head type magnetencephalography using an auditory oddball paradigm in passive mode. The authors also compared six stimulus combinations in order to find the optimal stimulus parameters for P300 magnetic field (P300m) in passive mode. Bilateral MUSIC peaks were located on the mesial temporal, superior temporal and parietal lobes. Interestingly, all MUSIC peaks in these regions emerged earlier in the right hemisphere than in the left hemisphere, suggesting that the right hemisphere has predominance over the left in the processing activity associated with P300m. There were no significant differences among the six stimulus combinations in evoking those P300m sources. The results of the present study suggest that the MUSIC algorithm could be a useful tool for analysis of the time-course of P300m. [source] Effects of monetary reward and punishment on stimulus-preceding negativityPSYCHOPHYSIOLOGY, Issue 3 2006Yoshimi Ohgami Abstract This study examined the effects of emotional valence on stimulus-preceding negativity (SPN) using reward and fine. A time estimation task under reward, punishment, combined, and control conditions was performed. Participants were rewarded for accurate responses in the reward condition, and were fined for incorrect estimations in the punishment condition. in the combined condition, correct responses were rewarded and incorrect responses were fined. In the control condition, neither a reward nor fine was used. Results showed a significant interaction of condition × hemisphere. The SPN at the left hemisphere was increased in the reward condition. For the punishment effect, although it evoked right hemisphere dominance, no conditional difference was apparent at the right hemisphere. These results suggest that the SPN is affected by positive emotion: The left hemisphere activation might represent a pleasant emotion accompanying monetary gain. [source] | |||||||||||||||||||||||||||||||