A subcortical circuit linking the cerebellum to the basal ganglia engaged in vocal learning
Résumé
Speech is a complex sensorimotor skill, and vocal learning involves both the basal ganglia and the cerebellum. These subcortical structures interact indirectly through their respective
loops with thalamo-cortical and brainstem networks, and directly via subcortical pathways, but the
role of their interaction during sensorimotor learning remains undetermined. While songbirds and
their song-dedicated basal ganglia-thalamo-cortical circuitry offer a unique opportunity to study
subcortical circuits involved in vocal learning, the cerebellar contribution to avian song learning
remains unknown. We demonstrate that the cerebellum provides a strong input to the song-related
basal ganglia nucleus in zebra finches. Cerebellar signals are transmitted to the basal ganglia via a
disynaptic connection through the thalamus and then conveyed to their cortical target and to the
premotor nucleus controlling song production. Finally, cerebellar lesions impair juvenile song
learning, opening new opportunities to investigate how subcortical interactions between the
cerebellum and basal ganglia contribute to sensorimotor learning.
Domaines
Sciences cognitives
Origine : Publication financée par une institution