RT Journal Article
SR Electronic
T1 Recurrent inhibition in striatum enables transfer of time-flexible skills to basal ganglia
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 110072
DO 10.1101/110072
A1 James M. Murray
A1 G. Sean Escola
YR 2017
UL http://biorxiv.org/content/early/2017/02/21/110072.abstract
AB The basal ganglia play a major role in directing learned action sequences such as reaching and pressing, particularly in cases where precise timing plays an important role, as shown in experiments on rodents performing delayed lever press tasks. A comprehensive understanding of the relative roles of cortex and basal ganglia in learning and performing such behaviors, however, is still lacking. Inspired by recent experimental results showing that motor cortex is necessary for learning certain types of motor sequences but not for performing them once learned, we develop a model of the striatum, the major input structure of the basal ganglia, in which recurrently connected inhibitory neurons receive cortical input. An anti-Hebbian plasticity rule at the recurrent synapses in the striatum allows our model to learn a sparse, sequential pattern of neural activity similar to the patterns observed in experimental population recordings. After learning, the network can reproduce the same dynamics autonomously without patterned cortical input, and can further speed up or slow down the activity pattern simply by adjusting the level of tonic external input. The general mechanisms used in this model can also be applied to circuits with both excitatory and inhibitory populations, and hence may underlie sequential neural activity patterns that have been observed throughout other brain areas in addition to basal ganglia.