DIFFERENTIAL EFFECTS OF RESECTIONS OF SOMATIC AREAS I AND II IN MONKEYS

Abstract

The performance of 8 monkeys (Macaca mulatta) on 6 somesthetic discriminations (multiple cue, size and form, form, and 3 degrees of roughness) was studied preoperatively and after post-rolandic resections. The results indicated that monkeys with somatic area I lesions fail to retain, and have marked difficulty relearning, most of the tasks. This somatic disturbance was duplicated and not exacerbated by combined removals of somatic area I and II, and Brodmann''s areas 5 and 7. Lesions restricted to somatic area II seemed to have little or no effect on test performance and the integrity of somatic area II could not compensate for a loss of somatic area I.