An analysis of the importance of S-R spatial continguity for proficient primate discrimination performance.

Abstract
2 groups of 8 rhesus monkeys were presented a difficult pattern discrimination task under conditions of spatial contiguity (C) and discontiguity (D) of discriminative stimulus and instrumental response in the order C-D-C for Group A, and D-C-C for Group B. Group A asymptotically learned under initial C condition, whereas Group B did not learn under initial D condition; when switched, Group A performed discriminations very poorly under D, while Group B began to learn under C; the groups performed identically well under final C condition. Attenuated probability of stimulus sampling was discussed as being the basis of the S-R spatial discontiguity effect.