Population code for tracking velocity based on cerebellar Purkinje cell simple spike firing in monkeys.
Velocity is an important determinant of the simple spike discharge of cerebellar Purkinje cells. In a previous study, Purkinje cells in the intermediate and lateral cerebellum recorded during manual tracking were found to be tuned to a combination of direction and speed, (i.e. preferred velocity). In this study a population analysis of this simple spike discharge was used to determine whether the velocity of tracking could be predicted. For the majority (30/32) of direction-speed combinations, the population response accurately specified the target velocity. A temporal analysis showed how the population response gradually converged to the required velocity 200 ms prior to the onset of tracking. Therefore, the simple spike discharge of a Purkinje cell ensemble contains sufficient information to reconstruct target velocity, providing support for the hypothesis that the cerebellum controls or signals movement velocity.
Coltz
J D
JD
Department of Neuroscience, University of Minnesota, Lions Research Building, Minneapolis, MN 55455, USA.
Johnson
M T
MT
Ebner
T J
TJ
D000818:Animals; D001132:Arm; D002531:Cerebellum / Q000502:physiology*; D003463:Cues; D000882:Haplorhini; D011597:Psychomotor Performance / Q000502:physiology*; D011689:Purkinje Cells / Q000502:physiology*; D011698:Pursuit, Smooth / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology*; D012044:Regression Analysis