Over the past decade research has suggested that stutterers have bilateral cerebral motor or auditory speech areas. Three typical adult stutterers showed normal unilateral left cerebral dominance for speech on the intracarotid sodium amylobarbitone (amytal) test, but one 'dysphatic' stutterer had bilateral cortical speech representation. The latter is a very rare finding in right handed individ...

Around 90% of humans prefer their right hand for unimanual actions and are lefthemisphere dominant for language functions; a pattern far from negligible. The phenomena of handedness and cerebral lateralization for language are presented along with the different theories that attempt to explain the presence of these functional asymmetries. The focus is on the adaptive advantages both on the indi...

Cerebral lateralization is intertwined with virtually every cognitive function that we think makes us human. Yet a clear dichotomy has never been explained: lateralized processing suggests independent, local development of neural circuits, but the complementary nature of lateralized functions and extremely strong functional coupling between homologous areas suggest robust interhemispheric inter...

The present study examined the relationship between sex-role identity (SRI) and functional cerebral lateralization (FCL) in right-handed males. Two tasks (figure task and location task) were used to assess FCL. The figure task required the identification of shape stimuli, while the location task involved identification of the position of stimuli. SRI was assessed by the Bem Sex Role Inventory (...

What causes critical periods (CPs) to open? For the best-studied case, ocular dominance plasticity in primary visual cortex in response to monocular deprivation (MD), the maturation of inhibition is necessary and sufficient. How does inhibition open the CP? We present a theory: the transition from pre-CP to CP plasticity arises because inhibition preferentially suppresses responses to spontaneo...

Recent lesion studies have shown that left hemisphere lesions often give rise to frank sign language aphasias in deaf signers, whereas right hemisphere lesions do not, suggesting similar patterns of hemispheric asymmetry for signed and spoken language. We present here a case of a left-handed, deaf, life-long signer who became aphasic after a right-hemisphere lesion. The subject exhibits deficit...

Recent evidence suggests that a combination of shyness and sociability is associated with distinct behavioral and psychophysiological correlates at rest and in response to social stress and may be a risk factor for developmental psychopathology in children and illicit substance use in adolescents and young adults. Using the Cheek and Buss (1981) measurement model on the relative independence of...

A case study of a right-handed individual with epilepsy and brain dysfunction of early onset is described who was found, following callosotomy (sparing the rostrum of the callosum) to be left hemisphere "dominant" for processing and/or expressing emotional and somesthetic information, and right hemisphere "dominant" in regard to the expression and comprehension of language and linguistic stimul...

Asymmetry of the human cerebellum was investigated using intrinsic functional connectivity. Regions of functional asymmetry within the cerebellum were identified during resting-state functional MRI (n = 500 subjects) and replicated in an independent cohort (n = 500 subjects). The most strongly right lateralized cerebellar regions fell within the posterior lobe, including crus I and crus II, in ...