Article on what basal ganglia neurons do during learning. In summary,
In Graybiel’s experiments, rats learned via specific cues that there was chocolate at one end of a T-shaped maze. While the rats were still learning, their basal ganglia neurons chattered throughout the maze run
As the rats learned to focus in on guiding cues (in the experiment, an audible tone that guided them toward the chocolate), the behavior of the neurons changed. They fired intensely at the beginning and the end, but remained relatively quiet while the rats scurried through the maze.
Subsequently, the reward was removed. While the audible cue became meaningless, everything in the maze from beginning to end became relevant again. The neurons fired throughout the run. But when the reward reappeared, the pattern of beginning and ending spikes separated by downtime reappeared.
Terra D. Barnes, Yasuo Kubota, Dan Hu1, Dezhe Z. Jin and Ann M. Graybiel1. Activity of striatal neurons reflects dynamic encoding and recoding of procedural memories. Nature 437, 1158-1161 (20 October 2005)