Delta gamma oscillatory interactions support visuomotor processing in the lateral frontal cortex of macaque monkeys

Visuomotor processing, the cognitive process by which visual information motivates motor action, is a fundamental process of mammalian brain function involving areas in the lateral frontal cortex. Specifically, in the frontal eye field (FEF) and premotor cortex (PM), frequency-dependent modulation of neural oscillations has been observed in association with visual perception and motor planning, respectively. However, whether the combination of neural signals in different frequency bands is related to information processing remains unclear. Here, we show phase coherence of delta band oscillations and phase amplitude coupling of delta and gamma band oscillations in electrocorticogram (ECoG) signals from FEF and PM, in monkeys during visuomotor tasks. Event-related phase signal in the delta frequency band and the coupling signal between the delta and gamma frequency bands were observed in respond to visual instruction and around movement onset. The spatial patterns of phase coherence and phase‒amplitude coupling could discriminate the task conditions. The phase of the delta oscillations and amplitude of the gamma oscillations may play roles in visuomotor processing in the FEF and PM.