Thus, burst-pause firing activity in cholinergic interneurons creates a temporal window in which a transient presynaptic inhibition, mediated by M2, is followed by a period of enhanced postsynaptic excitability triggered by M1 receptors in striatopallidal MSNs. During this period, the striatal network is strongly biased toward cortical activation of striatopallidal MSN ensembles [15]. The indirect pathway, anchored by striatopallidal MSNs is widely thought to be responsible for creating a “no-go” signal to the motor thalamus [39]. Indeed, recording in behaving monkeys suggest that strongest responses of TANs were self-timed No-Go responses [40].
