Fig. 2
From: Control of cortical oscillatory frequency by a closed-loop system
Sample recording traces, stimulation configuration and SO frequency behavior across injected DC currents. a Sample recording (3 s). Bottom row, raw LFP trace; middle and top rows, the MUA and MUA waveforms, respectively, obtained with online filtering of the LFP. Up states (gray shade) were automatically recognized through the use of amplitude and time thresholds in the MUA traces. b Scheme of electrode stimulation setup. Electric fields were directed parallel to the polarization direction of pyramidal neurons. c Typical distribution of SO frequency across injected currents for one of the recorded slices (mean ± SD). For each stimulation current (x axis), all the measured values of the slow oscillation frequency obtained during the stimulation interval at that specific intensity were averaged (58 values). The logarithm of the SO frequency monotonically increases with the applied DC currents. The linear fit is superimposed [28] (p-value = 3.9182 × 10− 7). The variability of the response to the stimulation across the five tested slices is showed in the inset by superimposing the linear fits for each slice, after normalization to the control condition (spontaneous activity). LFP, local field potential; MUA, multiunit activity; SO, slow oscillations