THE EFFECT OF MONOCULAR VIEWING ON HEARTBEAT DISCRIMINATION

In monocular viewing conditions, an activational imbalance between the cerebral hemispheres was assumed to develop, the direction of which d epends on the side of the viewing eye. This assumption was based on th e morphological differences between the nasal and the temporal hemiret inas and on physiological data. It was assumed that the hemisphere rec eiving visual information via the nasal optic fibers, that is, the hem isphere contralateral to the viewing eye, would be the more activated one. Because heartbeat perception is regarded as a predominantly right hemispheric function, it was predicted that during right hemispheric activation created by left monocular viewing heartbeat discrimination performance would be better than during left hemispheric activation cr eated by right monocular viewing. This hypothesis was tested on 30 mal e right-handed university students who performed a Whitehead-type hear tbeat discrimination task while viewing only with the left or with the right eye. Heartbeat perception was more accurate when viewing with t he left eye. Additionally, respiratory manipulation during heartbeat d iscrimination improved performance on this task.