RT Journal Article
SR Electronic
T1 Cerebellar Encoding of Multiple Candidate Error Cues in the Service of Motor Learning
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 9880
OP 9890
DO 10.1523/JNEUROSCI.5114-13.2014
VO 34
IS 30
A1 Christine C. Guo
A1 Michael C. Ke
A1 Jennifer L. Raymond
YR 2014
UL http://www.jneurosci.org/content/34/30/9880.abstract
AB For learning to occur through trial and error, the nervous system must effectively detect and encode performance errors. To examine this process, we designed a set of oculomotor learning tasks with more than one visual object providing potential error cues, as would occur in a natural visual scene. A task-relevant visual target and a task-irrelevant visual background both influenced vestibulo-ocular reflex learning in rhesus monkeys. Thus, motor learning does not identify a single error cue based on behavioral relevance, but can be simultaneously influenced by more than one cue. Moreover, the relative weighting of the different cues could vary. If the speed of the visual target's motion on the retina was low (≪1°/s), background motion dominated learning, but if target speed was high, the effects of the background were suppressed. The target and background motion had similar, nonlinear effects on the putative neural instructive signals carried by cerebellar climbing fibers, but with a stronger influence of the background on the climbing fibers than on learning. In contrast, putative neural instructive signals carried by the simple spikes of Purkinje cells were influenced solely by the motion of the visual target. Because they are influenced by different cues during training, joint control of learning by the climbing fibers and Purkinje cells may expand the learning capacity of the cerebellar circuit.