Accession Number:

ADA094537

Title:

Brain Responses and Information Processing I. Hemispheric Asymmetries in Event Related Potentials during Signal Detection.

Descriptive Note:

Annual rept. no. 1, 1 Oct 79-30 Sep 80,

Corporate Author:

BARUCH COLL NEW YORK PSYCHOPHYSIOLOGY LAB

Report Date:

1980-11-30

Pagination or Media Count:

63.0

Abstract:

Event-Related Potentials ERPs were recorded from over the two cerebral hemispheres occipital and parietal areas during a 78 minute vigilance task. Twelve right-handed male subjects served in two experimental sessions. These subjects focussed on a central fixation point and responded to signals presented at unpredictable times in one of three locations 2.5 deg. to right of the central fixation, central, and 2.5 deg to the left of center. Subjects decided whether to press a response key with either the left or right hand with each presentation. Signals were letter Ts oriented either right-side up or upside down. Six responded to T-up with right hands and six did the opposite. The ERPs were recorded from two scalp areas over left and right occipital cortex, and two sites above left and right parietal areas. Vertical and horizontal eye movements were also recorded. Two major ERP components emerged a negative peak occurring at about 180 msec. after the stimulus, and a positive component appearing at about 320 msec. ERP latency asymmetries occurred at all recording sites as a function of visual field of stimulation. That is, for the N180 component stimuli presented in the left visual field LVF resulted in shorter latency ERPs at the contralateral right hemisphere than at the ipsilateral left hemisphere. A contralateral advantage was also observed for stimuli presented in the RVF.

Subject Categories:

  • Psychology
  • Anatomy and Physiology

Distribution Statement:

APPROVED FOR PUBLIC RELEASE