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bioRxiv · 10.1101/2024.09.06.611733

The serotonergic psychedelic DOI impairs deviance detection in the auditory cortex

Abstract

Psychedelics are known to induce profound perceptual distortions, yet the neural mechanisms underlying these effects, particularly within the auditory system, remain poorly understood. In this study, we investigated the effects of the psychedelic compound 2,5-Dimethoxy-4-iodoamphetamine (DOI), a serotonin 2A receptor agonist, on the activity of neurons in the auditory cortex of awake mice. We examined whether DOI administration alters sound-frequency tuning, variability in neural responses, and deviance detection (a neural process reflecting the balance between top-down and bottom-up processing). Our results show that while DOI does not alter the frequency selectivity of auditory cortical neurons in a consistent manner, it increases trial-by-trial variability in responses and consistently diminishes the neural distinction between expected (standard) and unexpected (oddball) stimuli. This reduction in deviance detection was primarily driven by a decrease in the response to oddball sounds, suggesting that DOI dampens the auditory cortexs sensitivity to unexpected events. These findings provide insights into how psychedelics disrupt sensory processing and shed light on the neural mechanisms underlying the altered perception of auditory stimuli observed in the psychedelic state. New & NoteworthyThe neural basis of perceptual distortions induced by psychedelics remains poorly understood. This study demonstrates that the serotonergic psychedelic DOI increases neural response variability and impairs deviance detection in the auditory cortex by reducing sensitivity to unexpected sounds. These findings provide new insights into how psychedelics disrupt sensory processing and alter the balance between bottom-up and top-down neural signaling, contributing to our understanding of altered perception in the psychedelic state.

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BibTeXRIS

Horrocks, M., Mohn, J. L., Jaramillo, S.. 2024-09-12. The serotonergic psychedelic DOI impairs deviance detection in the auditory cortex. https://doi.org/10.1101/2024.09.06.611733

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