Supplementary Figure 3: Emergence of dmPFC 4-Hz oscillations during contextual fear behaviour.

(a, b) Protocol and behavioural results. During Habituation (Hab.), mice (n = 6) exhibited low freezing whereas following contextual fear conditioning (Day 2: Retrieval), freezing values were significantly increased (Paired t-test, Hab. versus Retrieval: t(5) = -11.639, *** P < 0.001). (c) Representative dmPFC raw LFP traces recorded during the Retrieval session. 4 Hz oscillatory activity is visible during freezing behaviour. (d) Representative spectrogram of dmPFC LFPs at a fine time resolution during freezing episodes at Retrieval. White lines on the spectrogram indicate freezing episodes. (e) Averaged power spectrum of dmPFC LFPs recorded during Retrieval for freezing and no freezing periods (n = 6 mice). Inset: Averaged dmPFC 2-6 Hz power during Retrieval for freezing and no freezing periods (Paired t-test, Freezing versus No Freezing: t(5) = -6.039, *** P < 0.001). a.u.: arbitrary units. Spectral power in log scale. Shaded area and error bars: mean ± s.e.m. For the representative examples (c, d), similar results were obtained for the 6 animals used in these experiments.