Computational Neuroscience Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
Mario Negrello
Computational Neuroscience Unit, Okinawa Institute of Science and Technology, Okinawa, Japan; Department of Neuroscience, Erasmus Medical Center, Rotterdam, The Netherlands
Marc Junker
Department of Cognitive Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
Aleksandra Smilgin
Department of Cognitive Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
Peter Thier
Department of Cognitive Neurology, Hertie Institute for Clinical Brain Research, University of Tübingen, Tübingen, Germany
Erik De Schutter
Computational Neuroscience Unit, Okinawa Institute of Science and Technology, Okinawa, Japan
Purkinje cells (PC), the sole output neurons of the cerebellar cortex, encode sensorimotor information, but how they do it remains a matter of debate. Here we show that PCs use a multiplexed spike code. Synchrony/spike time and firing rate encode different information in behaving monkeys during saccadic eye motion tasks. Using the local field potential (LFP) as a probe of local network activity, we found that infrequent pause spikes, which initiated or terminated intermittent pauses in simple spike trains, provide a temporally reliable signal for eye motion onset, with strong phase-coupling to the β/γ band LFP. Concurrently, regularly firing, non-pause spikes were weakly correlated with the LFP, but were crucial to linear encoding of eye movement kinematics by firing rate. Therefore, PC spike trains can simultaneously convey information necessary to achieve precision in both timing and continuous control of motion.
