which spontaneously occurs at ~2 Hz (Kiss et al., 2011a, 2011b) can be increased by RPO stimulation to generate sharp spectral peaks across the entire 2–5 Hz range found in awake rats (Fujisawa and Buzsaki 2011). We also found that, as in the awake animal, both theta and this 2–5 Hz oscillation were commonly present and correlated in HC and PFC and, as we additionally show here, in the nRE.
