RT Journal Article
SR Electronic
T1 Dissociating Timing and Coordination as Functions of the Cerebellum
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 6291
OP 6301
DO 10.1523/JNEUROSCI.0061-07.2007
VO 27
IS 23
A1 Jörn Diedrichsen
A1 Sarah E. Criscimagna-Hemminger
A1 Reza Shadmehr
YR 2007
UL http://www.jneurosci.org/content/27/23/6291.abstract
AB The function of the cerebellum in motor control is a long-standing puzzle because cerebellar damage is associated with both timing and coordination deficits. Timing is the ability to produce consistent intervals between movements based on an internal representation of time. Coordination, in contrast, is a state-dependent control process in which motor commands to one effector depend on the predicted state of another effector. Here we considered a task consisting of two components, an arm movement and an isometric press with the thumb. We found that when the two components temporally overlapped, the brain controlled the thumb using an estimate of the state of the arm. In contrast, when the components did not temporally overlap, the brain controlled the thumb solely based on an internal estimate of time. Using functional magnetic resonance imaging, we contrasted these two conditions and found that lobule V of the cerebellum ipsilateral to the arm movement was consistently more activated during state-dependent control. When the brain learned time-dependent control, no region of the cerebellum showed consistently increased activity compared with state-dependent control. Rather, the consistent activity associated with time-dependent control was found in language areas of the left cerebral hemisphere along the Sylvian fissure. We suggest that timing and coordination are behaviorally distinct modes of motor control and that the anterior cerebellum is a crucial node in state-dependent motor control, computing a predictive state estimate of one effector (e.g., the arm) to coordinate actions of another effector (the thumb).