(A) Experimental protocol. See text for detailed description.
(B) Wavelet transform (color plot) of BLA LFP (gray) recorded during recall session (Day 4). Lower traces, slow (40-70 Hz, green) and fast (70-120 Hz, blue) gamma events, occurring at distinct phases of the theta oscillation (black). Boxes indicate representative high-amplitude gamma events in each frequency band.
(C) Phase-Amplitude comodugram of a representative BLA LFP recording demonstrating modulation of high frequency power (y-axis) by low frequency oscillation phase (x-axis). Warm colors indicate stronger modulation; note the prominent modulation of separate slow (40-70 Hz) and fast (70-120 Hz) gamma peaks.
(D) Histograms for the occurrence of slow gamma troughs, fast gamma troughs and multi-unit spikes (top three panels) and the preferred phase of significantly phase-locked (p < .05, Rayleigh test) multi-units (n=48) and single units (n=38; bottom two panels) relative to phases of the theta (4-12 Hz) oscillation. Error bars, here and throughout, are +/− SEM, except as otherwise noted.