Deficits in non-spatial conditional associative learning after periarcuate lesions in the monkey.

Monkeys with lesions of the periarcuate region of the frontal cortex were severely impaired in learning a nonspatial conditional associative task. In this task, either one of two non-spatial responses (open the lit or the unlit box) was correct if emitted in the presence of the appropriate stimulus. In contrast, the periarcuate monkeys were able to learn, at a normal rate, the control tasks in which only one of the two responses was correct (e.g., go to the lit box), the animal's task being to emit this response when the cue to do so was given. These findings support the hypothesis that the periarcuate cortex is critically involved in conditional associative learning.