Figure 3.
MUA can also reflect β/γ oscillations, but it is generally a less sensitive measure than LFP. A, Example of the different data obtained from the extracellular recording: LFP signal (bandpass filtered, between 2 and 150 Hz), MU-extra (high-pass filtered, 5 Hz), and MUA (events thresholded from the high-pass filtered signal). B, Analyses of the MUA data shown in A (same recording as shown in Fig. 1): time-histogram (PSTH, left) triggered by up state transitions detected from LFP (see Fig. 1); normalized power spectrum showing a peak in the β/γ range (middle); and autocorrelation function (right). C, Average results for a population of 10 recordings (same as used in Figs. 4–10) show that although up states (red) had greater power in the β/γ band than down states (blue) as assessed from the LFP power spectra (left), this was not evidenced clearly in the averaged MUA power spectrum (middle) or in the averaged autocorrelation function (right). Shades indicate 95% CI.