Handedness, Eye-Dominance, and Immediate Memory

Twenty male university students varying in handedness and eye-dominance recalled conventional and unconventional digits under two conditions: (1) when the same type of digit was projected simultaneously to each eye, and (2) when a different type of digit was projected simultaneously to each eye. Forty trials were given, each consisting of four pairs of digits with a different numeral projected to each eye. Performance was analysed in terms of percentage recalled correctly and time of onset of each response. Right eye-dominant groups, particularly a right handed and right eye-dominant group, were superior in both accuracy of recall and speed of response to left eye-dominant groups. Least able in recall were left handed, left eye-dominant subjects. Superiority of right eye-dominant groups was especially marked when a different type of digit was projected to each eye. In accord with results reported by Broadbent for the ears (1956, 1957), other results suggest it is possible for the eyes to operate simultaneously as independent information sources. However, unlike the case for audition, present subjects did not report all information from one eye before that from the other, but gave it in pairs. It seems that the capacity of the eyes to function independently depended upon eye-dominance and handedness, while serial ordering of responses reflected imposition of an habitual response organization.