Oscillations of local field potentials in the rat dorsal striatum during spontaneous and instructed behaviors.

Oscillatory activity is a candidate mechanism for providing frequency coding for the generation, storage and replay of sequential representations of events and episodes. We recorded local field potentials (LFPs) and spike activity in the striatum, a basal ganglia structure implicated in behavioral action-sequence learning and performance, as rats engaged in spontaneous and instructed behaviors in a T-maze task. We found that during voluntary behaviors, striatal LFPs exhibit prominent theta-band oscillations together with rhythms at higher and lower frequencies. Analysis of the theta-band activity demonstrated that these oscillations are strongly modulated during task performance and increase as the animals choose and execute their turning responses in the cue-instructed T-maze task. These theta rhythms are locally generated and are coherent across large parts of the striatum. We suggest that modulation of oscillatory activity in the striatum may be a key feature of neural processing related to the control of voluntary behavior.