Figure 2

Ketamine differentially affects gamma and HFO power. (A1, A2) Example spectrograms of time courses showing the effect of saline and ketamine injection on LFP oscillations recorded in the OB. (B1) Time-courses showing the effect of ketamine injection on the power of low gamma (30–70 Hz), high gamma (70–100 Hz) and HFO (130–180 Hz). (B2) Plots for individual rats showing the mean power at baseline and mean power post injection of ketamine (15 min blocks, N = 8 rats, as in Fig. 1). (C) Scatter plot showing the correlation between HFO power and proportion of fast sniffing (white circles) and beam breaks (black circles). Spearman r values are shown for each rat. (D1) 130–180 bandpass-filtered LFPs shortly after ketamine recorded from the left and right OB. Bursts of HFO often occurred at similar moments, however occasionally bursts were observed more clearly on one side only. (D2) Expansion of a single burst showing that although bursts are often coherent they are not in phase. (E) Mean and SEM coherence spectra for left vs. right OB recordings shortly after injection of ketamine (also compare with Fig. 4A4).