Year: 2022
Type: article
Abstract: New findings in PLOS Biology show that visual gamma oscillations are greatly attenuated by small spatial discontinuities in visual stimuli, suggesting that their genesis occurs in response to predictable regularities in the visual world.Periodic fluctuations in the brain's electrical activity, known as oscillations, have been the focus of neuroscientists for almost a century.These oscillations occur at different frequencies across brain regions and in response to a variety of stimuli or behaviors [1].Of particular research focus has been the striking high-frequency (30 to 80 cycles/second) gamma oscillations that occur within visual cortex.While a highly robust phenomenon across species, debate continues as to the functional significance of these visual gamma oscillations.In this issue of PLOS Biology, Shirhatti and colleagues [2] show that even subtle tweaks in the structure of specific gamma inducing stimuli greatly reduces the amplitude of this oscillation.These findings present important challenges for theories of gamma's functional role in visual cortex.However, as the authors show, these findings intimately relate to key physiological properties of neural circuits within visual cortex, opening new avenues for understanding gamma's genesis and function.Primary visual cortex (V1) is an essential structure of the visual system, containing neurons that increase their spiking activity in response to basic visual features such as lines and colors.When these features are presented as uniform patterns (e.g., striped lines or gratings; see Fig 1), groups of neurons fire repeatedly together.This synchrony of neural firing, along with related physiological events, appears as large amplitude gamma frequency oscillations in the electrical field potential.It has been proposed that gamma may serve to temporally align neural activities, either within a visual area to support the perceptual binding of line features in visual space or across visual areas to support neural communication along processing pathways [3].Experimental and computational work has grown in examining these and other claims regarding the origins and significance of gamma oscillations in vision and cognition.As the grating stimuli that induce strong gamma oscillations reflect a common stimulus in visual neuroscience, many studies have examined how changes in the attributes of gratings impact neural responses in visual cortex, including gamma.It is now clear that changing the properties of grating stimuli can parametrically impact the amplitude and/or frequency of induced visual gamma [4], consistently across species.Together, accumulating evidence
Source: PLoS Biology
Authors: Brett L. Foster, Eleonora Bartoli
Institutions: University of Pennsylvania, Baylor College of Medicine
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $5,300
OpenAlex ID: W4283647099