Psychedelic 5-HT2A agonist increases spontaneous and evoked 5-Hz oscillations in visual and retrosplenial cortex.

Theta waves (4-8 Hz) in the visual cortex are linked to cognitive states and perception, but their role in cortical activity and aberrant brain states is not fully understood. Using cortex-wide voltage imaging in awake mice, 5-Hz oscillations were found in both the visual and retrosplenial cortices, occurring spontaneously and when evoked by visual stimulation. Injection of a psychotropic 5-HT2AR agonist increased spontaneous 5-Hz oscillations and boosted the power, occurrence probability, and persistence of visually evoked 5-Hz oscillations. This modulation in both areas suggests strengthened top-down control of perception, supporting a mechanism underlying perceptual filling and visual hallucinations.

Study at a glance

Abstract

Visual perception appears largely stable in time. However, psychophysical studies have revealed that theta waves (4-8 Hz) can modulate perception and have been linked to various cognitive states and functions. Neither the contribution of theta waves to cortical activity nor their impact during aberrant brain states have been resolved at high spatiotemporal scales. Here, using cortex-wide population voltage imaging in awake mice, we found that bouts of 5-Hz oscillations in the visual cortex are accompanied by similar oscillations in the retrosplenial cortex, occurring both spontaneously and evoked by visual stimulation. Injection of psychotropic 5-HT2AR agonist induced a significant increase in spontaneous 5-Hz oscillations, and also increased the power, occurrence probability and temporal persistence of visually evoked 5-Hz oscillations. This modulation of 5-Hz oscillations in both cortical areas indicates a strengthening of top-down control of perception, supporting an underlying mechanism of perceptual filling and visual hallucinations.