Leading tonically active neurons of the striatum from reward detection to context recognition.

Tonically active neurons (TANs) in the primate striatum, which are presumed to be cholinergic interneurons, carry signals that are traditionally considered to be important for reward-related learning. Recent studies investigating the functional properties of TANs in behaving monkeys have shown that other factors beyond motivation can affect their responsiveness. There is now evidence that TAN responses reflect stimulus detection, movement control and recognition of a specific context, suggesting that these local circuit neurons contribute to different computations used in learning and action functions of the striatum. This is consistent with the view that TAN responses could represent an important component of the processes that are responsible for the ability to select the appropriate behavioral response to environmental events.