Discussion of nunuphar's comment: In many current optogenetic manipulation experiments targeting specific circuits, authors do not record from the relevant circuits, but instead are showing behavioral effects without addressing the complexity of the network effects that their manipulation may be producing. In this case, the authors specifically asked how their manipulation was affecting neuronal activity downstream the basal ganglia circuit and found a large proportion of units behaving in a manner that contradicted basic expectations (which is not surprising, but often not addressed). This also brings up the question of how these units are exerting the behavioral effects that they and others have observed after manipulating direct or indirect pathway neurons. A likely possibility is that speed is the critical factor and the units with the shorter latency responses are driving the behavioral response, consistent with their findings.

+1 for calling for in vivo recordings to check in on the effects of stimulation - I fully agree!

imalsogreg(36) 3 years ago