EYE AND HAND DOMINANCE IN KINDERGARTEN AND FIRST-GRADE CHILDREN

Abstract

The recent explosion of knowledge about the brain and its func tioning gives promise of insight into the varied expressive human behaviors hitherto categorized as physical (genetically determined) or learned (culturally trained) in origin. Until the late forties it was accepted that both of the cerebral hemispheres acted in a generally unilateral manner, and that if one hemisphere was traumatized the other side would supplant the behaviors of the injured half. It fol lowed, logically, that one side of the brain was dominant in most humans. As early as 1836, Dax (see Critchley, 1964) postulated that the hemisphere contralateral to the preferred hand was dominant. This theory has stood during the intervening 140 years with the support of neurophysiological evidence. Current research suggests that each cerebral hemisphere has its own unique function: the left hemisphere generally controlling verbal and spatial reactions and the right hemi sphere the affective domain as well as specific distal tasks (Penfield & Roberts, 1959; Delgado, 1969; Dirnond, 1970; Sperry, 1975; Gard ner, 1975). Schwartz, Davidson, and Maer (1975) report on right hemisphere lateralization for emotion, using lateral eye movement measures for assessment. Cognitive questions evoked movement of the right eye, suggesting activation of verbal and sequential processes associated with the left hemisphere (activation tends to produce orientation to the contralateral side of the body) while spatial emotional questions evoked left eye movements. Studies by Belmont and Birch (1963), Crinella, Beck and Robin son (1971), and Annett and Turner (1974) suggest that hemispheric dominance does not imply ipsiIateraIity in all motor behaviors. Hand edness must be viewed in the light of the task performed. Mixed