The squirrel monkey lacks anatomically demonstrable ocular dominance columns, and physiologically it has an ocular dominance distribution in V1 that is very different from that of macaques, with far fewer cells that strongly favor one eye over the other. We tested an alert squirrel monkey for physiological responses to stereoscopic stimuli by measuring evoked potentials in response to cytclopea...

Aphasia describes a spectrum of speech impairments due to damage in the language centers of the brain. Insult to the inferior frontal gyrus of the dominant cerebral hemisphere results in Broca's aphasia - the inability to produce fluent speech. The left cerebral hemisphere has historically been considered the dominant side, a characteristic long presumed to be related to a person's "handedness"...

The manifested dominance split-brain monkeys usually show for performing visual tasks through one hemisphere, when perceptual information is equally available to both, was analyzed. Three split-brain monkeys, each being trained similar yet different discriminations to each hemisphere, were allowed the opportunity to choose between the two problems when both were presented simultaneously. Initia...

ABSTRACT The human brain is lateralized, different functions being housed in each hemisphere. Several assumptions which are mistakenly considered fact by researchers include: (1}' the leff, hemisphere is for rational functions, while the right is for intuitive functions; (2) the hemispheres do not interact as well with each other as they should; (3) the use of one hemisphere tends to depress th...

Popular culture, from movies, advertising, to self-help books, is captivated by left-brain/rightbrain differences and how these might influence our personalities, moods, and capabilities. Considering the interest in understanding the scientific basis for lateralized neural functions, it is surprising that model systems have not played a more dominant role in research on brain asymmetry. The lon...

Dysgraphia due to a focal brain lesion can be characterized by substitution, transposition, deletion and/or addition errors of graphemes or strokes. However, those linguistic errors can be language-specific because the writing system of a given language may influence error patterns. We investigated a Korean stroke patient, a 57-year-old English teacher with dysgraphia both in Korean Han-geul [s...

Zif268 transcription factor is expressed throughout Cebus apella visual cortex at high basal levels. Monocular eyelid suture alters the levels of Zif268 on neurons connected to the deprived eye, revealing ocular dominance columns in the striate cortex of Cebus as previously demonstrated in Old World monkeys (Chaudhuri and Cynader, Brain Res., 605 (1993) 349-353). Zif268 ocular dominance columns...

Current theories of binocular vision suggest that the neural processes that resolve interocular conflict do not involve a single brain region but occur at multiple stages of visual processing. Here, using an adaptation paradigm, we explore the initial mechanisms involved in selecting a stimulus for perceptual dominance during binocular rivalry. When one or both eyes briefly viewed an adapting g...

In most people the left hemisphere of the brain is dominant for language. Because of the increased incidence of atypical right-hemispheric language in left-handed neurological patients, a systematic association between handedness and dominance has long been suspected. To clarify the relationship between handedness and language dominance in healthy subjects, we measured lateralization directly b...