Concepedia

TLDR

Synchronized oscillations are thought to link perceptual features, a hypothesis supported by stimulus‑specific oscillations in anesthetized cats but questioned by weak or absent oscillations reported in awake monkey visual cortex. We recorded high‑amplitude, 70–80 Hz synchronized oscillations in the spike activity and local field potentials of awake monkey V1, with stimulus specificity and amplitudes comparable to or exceeding those previously seen in cats.

Abstract

It has been proposed that synchronized oscillations play a key role in perceptual feature linking and sensory integration. This idea was supported by the discovery of strongly synchronized stimulus-specific oscillations in the visual cortex of anaesthetized cats. The 'synchronization hypothesis' was controversial because in the visual cortex of awake monkeys either only weak or no oscillations were found. We have now recorded high amplitude synchronized oscillation at the level of spike activity and local field potential from the primary visual cortex of an awake monkey. The dominant frequencies (70-80 Hz) were considerably higher than those observed previously in cats and monkeys (30-50 Hz). However, stimulus specificities of the oscillations were comparable to and amplitudes even higher than those in cats.