Mechanisms of Movement-Related Changes in Auditory Detection
To successfully navigate the world, our sensory systems must process stimuli accurately during both rest and movement. Indeed, movements have been shown to modulate sensory systems at different levels. In audition, studies in humans and other animals have shown that movements strongly suppress auditory cortical responses to acoustic stimuli relative to rest. A largely untested idea is that this cortical suppression works to suppress responses to predictable acoustic consequences of movements, while enhancing sensitivity to novel stimuli. How this cortical suppression influences auditory perception and whether this suppression functions predictively as widely theorized remain unknown. Here, I trained head-fixed mice to lick in response to tones of different intensities during rest or running on a quiet treadmill. I observed that auditory detection was impaired during running compared to rest. Inactivating the auditory cortex impaired detection, and optogenetically activating secondary motor cortical axons in the auditory cortex during rest degraded detection similar to movement. Finally, movement-related impairment of auditory detection was specific to expected sounds following predictable sensorimotor experience. Overall, these findings support the idea that movement-related modulation of auditory cortical activity is behaviorally adaptive, selectively suppressing predictable movement-related sounds while enhancing sensitivity to novel stimuli.
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