Figure 1

Effect of ketamine (subanesthetic and anesthetic doses) and KX anesthesia on 30–65 Hz and 100–180 Hz oscillations in the rat OB. First row (A–D) presents results for subanesthetic ketamine 25 mg/kg, second row (E–I) for ketamine 100 mg/kg + xylazine 10 mg/kg (KX) anesthesia and third row for anesthetic dose of ketamine 200 mg/kg. First column (A,E,J): Example spectrograms computed from the OB before and after injection. Dotted line at \(t\,=\,0\) is injection time. Second column (B,F,K): Example raw waveform (bottom) and filtered signal in HFO band 100–180 Hz (top). Third column (C,G,L): Extracted data from spectrograms of the power of dominant frequency for 30–65 Hz and 100–180 Hz activity (mean across rats n = 8). The column (D,H,M): Individual traces of HFO and gamma power taken from three time points (marked with grey bars in C,G,L plots). Both subanesthetic ketamine and KX administration reduced gamma power and substantially increased HFO power (*p<0.05, **p<0.01, ***p<0.001, and n.s. (not significant) with respect to baseline). (I,O): Comparison of dominant frequency for the 100–180 Hz band just after injection of ketamine 25 mg/kg or KX for early E and late L time points (**p<0.01, ***p<0.001).