Responses to visual stimuli of single cortical neurons in arcuate and prearcuate regions were studied in 6 immobilized macaque monkeys. Neurons responding to visual stimuli were found in both regions, some of them responded to conventional light stimuli, others required more complex visual stimulation. The former were found posteriorly in the arcuate region, the latter anterioly and in the prearcuate region. According to their functional properties the latter neurons were subdivided into: (a) neurons responding to stimuli near the eyes; (b) neurons triggered by complex visual stimuli; (c) neurons inhibited by visual stimuli.