Dissociation of deficits on auditory tasks following partial prefrontal lesions in monkeys

Separate groups of normal monkeys were trained either in Pavlovian differentiation or in positional responses, and with either auditory frequency or auditory location cues. After reaching criterion, half the animals in each group were given a dorsal prefrontal lesion and the other half, a ventral prefrontal lesion. The dorsal removal produced a strong impairment on the positional response tasks but none on Pavlovian differentiation, whereas the ventral removal produced a severe impairment on Pavlovian differentiation and only a mild deficit in the positional response tasks. This dissociation of deficits after prefrontal lesions is discussed within the framework of the neural theory of conditioning elaborated in Konorski's "Integrative Activity of the Brain".