Gamma-band activity (30–90 Hz) and the synchronization of neural activity in the gamma-frequency range have been observed in different cortical and subcortical structures and have been associated with different cognitive functions. However, it is still unknown whether gamma-band synchronization subserves a single universal function or a diversity of functions across the full spectrum of cognitive processes. Here, we address this question reviewing the mechanisms of gamma-band oscillation generation and the functions associated with gamma-band activity across several cortical and subcortical structures. Additionally, we raise a plausible explanation of why gamma rhythms are found so ubiquitously across brain structures. Gamma band activity originates from the interplay between inhibition and excitation. We stress that gamma oscillations, associated with this interplay, originate from basic functional motifs that conferred advantages for low-level system processing and multiple cognitive functions throughout evolution. We illustrate the multifunctionality of gamma-band activity by considering its role in neural systems for perception, selective attention, memory, motivation and behavioral control. We conclude that gamma-band oscillations support multiple cognitive processes, rather than a single one, which, however, can be traced back to a limited set of circuit motifs which are found universally across species and brain structures.
Gamma-band synchronization (30–90 Hz) has been observed across several species, in different cortical and subcortical brain structures and it has been associated with different cognitive functions. However, it is still unknown whether gamma-band synchronization subserves a single universal function or a multiplicity of functions across all observed cognitive processes. Here, we assess this question by reviewing how gamma oscillations originate from neuronal circuits, what are the computational processes that gamma promote and what are the evolutionary roots that link gamma with neuronal computations. We conclude that gamma band synchronization supports several cognitive functions that can be traced back to a limited set of circuit motifs which are found universally across species and brain structures.