Topic: correlated inputs

The striatum is crucial for motor control and reinforcement learning. The striatum has only 1% fast-spiking interneurons (FSI) which constitute feedforward inhibition (FFI). Therefore, striatal neurons receive a high degree of shared FFI, which makes the striatum a unique network in the brain. Here we ask, what role such high shared FFI may play in striatal function besides inducing synchrony. We found that with highly shared connectivity FSIs increase the trial-by-trial variability of striatal responses. Moreover, when the striatum is driven by correlated inputs, FSIs decorrelate the response