The data were recorded from rat #5, rat #6 and rat #7. Similar format as Fig. 1. a, b, Left, Traces of LFP, raw (grey), filtered in theta (6–10 Hz, green) and eta (2.5–5.5 Hz, brown) bands during high-speed (above 15 cm/s) running on track (top) and at low-speeds (below 15 cm/s) (bottom) recorded in the VR. Middle, (bottom panel) Power spectra of the example LFPs in VR during running (red) and immobility (black), and (top panel) power index, during run compared to stop, showing prominent peaks in both eta and theta bands in VR (red). Right, Amplitude envelope distribution during high- (30–60 cm/s) and low- (5–15 cm/s) speed runs for the theta (top panel) and eta (bottom panel) bands in VR. Theta amplitude was significantly (rat #5, p < 10−10, X2 = 1430.5; rat #6, p < 10−10, X2 = 4357.1; rat #7, p < 10−10, X2 = 2661.0, KW test) larger at high speeds than low speeds, whereas eta amplitude was slightly smaller at high speeds (rat #5, p < 10−10, X2 = 3434.0; rat #6, p < 10−10, X2 = 12250.0; rat #7, p < 10−10, X2 = 1997.3, KW test).