Function-Related Gamma Oscillations and Conscious Perception

Frequency-domain techniques describe oscillations as a fundamental behavior of neurons and brain signals. Oscillations synchronize over large portions of cortex and mediate in the spatiotemporally coherent activation of neuron assemblies required for brain processing to occur. Oscillations in the gamma band (~20.0–80.0 Hz) originate from the tonic excitation of inhibitory interneuron networks, sustain rhythms and frequency constancy, and are enhanced during sensory, motor, or “cognitive” processes through frequency-dependent and function-related neuronal synchronization. Experimental work indicates a role of gamma activity in conscious perception. Further investigation is, nevertheless, warranted as gamma-band synchronization plays a functional role in low-level phase coding as well as in high-complexity neural processes related to perception, such as selective attention, focused arousal, multistable or ambiguous perceptive conditions, visuomotor integration, and associative learning.