Neural and behavioral dynamics of encoding, production and synchronization with external rhythms in subcortical lesion patients

Abstract

AbstractActing in and adapting to a dynamically changing environment necessitates precise encoding of the temporal unfolding of sensory events around us and to thetimeof our own (re-)actions to them.Cerebellar (CE) and basal ganglia (BG) circuitries play fundamental and complementary roles in the timing of sensory events. While the CE seems to encode the precise timing of sensory events (whenan event occurs), the BG engage in generating temporal predictions (whena next event occurs). However, their contributions are rarely investigated in combination, as it is generally difficult to record data from respective patient groups in parallel.Here we investigated the contributions and causal roles of CE and BG in sensory and sensorimotor timing processing. Healthy controls and patients with lesions in either CE or BG listened to isochronous auditory sequences while their EEG was recorded and later performed a tapping synchronization task. We characterized intra- and inter-individual variabilities, as well as group differences, in delta-band phase-coherence, power fluctuations, and dynamics of acceleration, deviation and stability while tuning delta-band oscillations and tapping to the rhythm of the auditory sequence.Combined behavioral and neurophysiological results confirm that patients displayed heterogeneity and altered capacity to synchronize ongoing neural activity and behavior with temporal regularities in the acoustic environment. These results confirm and differentiate the causal roles of the CE and BG in temporal processing as well as in the production and synchronization with temporally regular sound events.