PT - JOURNAL ARTICLE AU - Olson, William P. AU - Chokshi, Varun B. AU - Kim, Jeong Jun AU - Cowan, Noah AU - O’Connor, Daniel H. TI - Muscle spindles provide flexible sensory feedback for movement sequences AID - 10.1101/2024.09.13.612899 DP - 2024 Jan 01 TA - bioRxiv PG - 2024.09.13.612899 4099 - http://biorxiv.org/content/early/2024/09/20/2024.09.13.612899.short 4100 - http://biorxiv.org/content/early/2024/09/20/2024.09.13.612899.full AB - Sensory feedback is essential for motor performance and must adapt to task demands. Muscle spindle afferents (MSAs) are a major primary source of feedback about movement, and their responses are readily modulated online by gain-controller fusimotor neurons and other mechanisms. They are therefore a powerful site for implementing flexible sensorimotor control. We recorded from MSAs innervating the jaw musculature during performance of a directed lick sequence task. Jaw MSAs encoded complex jaw–tongue kinematics. However, kinematic encoding alone accounted for less than half of MSA spiking variability. MSA representations of kinematics changed based on sequence progression (beginning, middle, or end of the sequence, or reward consumption), suggesting that MSAs are flexibly tuned across the task. Dynamic control of incoming feedback signals from MSAs may be a strategy for adaptable sensorimotor control during performance of complex behaviors.Competing Interest StatementThe authors have declared no competing interest.