Rapid integration of somatosensory feedback in planning tongue movements

Abstract

The brain dynamically generates motor actions based on fast-changing sensory feedback arising from previous actions and the environment.1,2 How neural circuits carry out flexible motor control at fast timescales remains incompletely understood. Here we developed a probabilistic sequence licking task, in which mice adjust lick angles from lick to lick based on lingual somatosensory feedback. Motor planning in sequences of licks flexibly directed on-the-fly depended on orofacial cortical activity on a lick-by-lick timescale. Population activity in the orofacial cortices and superior colliculus generates an internal estimate of lick target position, based on cortical processing of somatosensory feedback. Persistent memory of lick target position absent sensory feedback is maintained in the orofacial motor cortex. Our results show how a multiregional circuit carries out sensory processing, motor preparation, and motor execution within rapid sequences of orofacial movements.