Theta, but Not Gamma Oscillations in Area V4 Depend on Input from Primary Visual Cortex.

摘要: Summary Theta (3–9 Hz) and gamma (30–100 Hz) oscillations have been observed at different levels along the hierarchy of cortical areas across a wide set cognitive tasks. In visual system, emergence both rhythms in primary cortex (V1) mid-level V4 has linked with variations perceptual reaction times. 1 , 2 3 4 5 Based on analytical methods to infer causality neural activation patterns, it was concluded that theta might reflect feedforward sensory processing from V1 V4. 6 7 8 9 10 Here, we report experiments macaque monkeys which experimentally assessed presence activity recorded multi-electrode arrays before after permanent lesion. With intact cortex, could be reliably elicited when viewed contour illusion showed phase-to-amplitude coupling. Laminar analysis revealed occurred primarily supragranular layers, output compartment V1. However, there clear dissociation between two became apparent major input removed by lesioning V1: although eliminated theta, had little effect power except for delaying its >100 ms. These findings suggest is more tightly associated than pose limits proposed role as mechanism.