Fig. 4.

Medial frontal delta and theta rhythms depend on dopamine. A, left: normalized EEG ERP from 13 matched control participants (blue) and PD patients (red) revealed peaks ∼0.2 s from the onset of the cue on midfrontal lead Cz. At right, the topographic distribution of ERPs over MFC are plotted (0.1–0.2 s after cue) in controls (left) and in PD patients (right). Time-frequency analysis of signals from lead Cz revealed a prominent burst of delta and theta activity (∼2–6 Hz) in matched controls (B), while patients with PD had deactivations 0.5–1.0 s following the cue (C). D: the between-group subtraction revealed that PD patients had significantly less low-frequency activity (∼2–4 Hz) than the matched controls. E: rodents had delta and theta cue-triggered activity (∼2–4 Hz; note that these data are similar to Fig. 3D in a different set of rodents) over MFC. F: with MFC dopamine depletion, deactivation was seen in this band. G: the between-group subtraction revealed that depleting dopamine in the MFC significantly minimizes the low-frequency activity (∼2–5 Hz) compared with control animals. Black lines indicate increases in power relative to baseline or matched controls in the subtraction condition at P < 0.05 via a t-test.