objective: in recent years different hypotheses with respect to the formation of cerebral laterality were proposed. some of the researchers claim that cerebral dominance and laterality are determined by genetic factors, just as the case with eye color and blood type. however, another group states that in addition to genetic factors, environmental factors, too, have a remarkable role in hemisphe...

introduction: emotional words in comparison with neutral words have different hemispheric specialization. it is assumed that the right hemisphere has a role in processing every kind of emotional word. the objective of the present study was the development of a persian version of the dichotic emotional word test and evaluate its validation among adult persian speakers.   materials and methods: t...

Early life environmental manipulations have been shown to affect hippocampal-dependent learning, hippocampal volume and cerebral lateralization. In this study, we investigated the effects of neonatal stimulation on hippocampal volumetric asymmetry. Long-Evans hooded rats were exposed to a novel non-home environment 3 min daily for the first 3 weeks of life. Histological measures of the left and...

Cerebral lateralization is a fundamental property of the human brain and a marker of successful development. Here we provide evidence that multiple mechanisms control asymmetry for distinct brain systems. Using intrinsic activity to measure asymmetry in 300 adults, we mapped the most strongly lateralized brain regions. Both men and women showed strong asymmetries with a significant, but small, ...

A test of cerebral dominance for language was administered to 51 cerebral palsied adults. The test consisted of dichotically presented words and in normal speaking adults had previously demonstrated very marked right ear superiority, interpreted as left cerebral dominance. The group of cerebral palsied subjects did not show the predicted right ear superiority. This finding may represent a chanc...

Two meta-analyses of 66 behavioral studies examined variables influencing functional cerebral lateralization of each language of brain-intact bilingual adults. Functional lateralization was found to be primarily influenced by age of onset of bilingualism: bilinguals who acquired both languages by 6 years of age showed bilateral hemispheric involvement for both languages, whereas those who acqui...

We describe a modification to a standard correlation model for the development of the geniculocortical projection that relays visual input to the visual cortex. The modification is to include threshold-activation of cortical cells as opposed to linear activation and it is shown that this can account for topographic map refinement (TMR). This contrasts with other models that require cortical cel...

The study examined the relationship between perinatal stress and decreased right handedness and decreased left cerebral dominance for speech with 215 children born prematurely, followed from birth, and tested at age 5. Results indicated that neither hand preference nor hand performance correlated with degree of perinatal stress and that eye preference was associated with perinatal stress though...