Fig. 2.

IML oscillations are abolished by the Na⁺ channel blocker TTX. (A) Low-pass filtered (<35 Hz) extracellular recording from the IML of a spinal cord slice. Application of 1 μM TTX reduced the activity in the slice. The trace did not recover upon removal of TTX. Grey regions were subjected to the analyses presented below. A segment of data from each of the grey regions is presented on a faster timescale below to show the oscillation more clearly. (B) Autocorrelograms of the grey regions, showing that the activity was self similar (sinusoidal plot) before, but not after, application of TTX. (C) Power spectra of the grey regions reveal the presence of a rhythm at 13 Hz, and a small harmonic at approximately twice this frequency. Both peaks were abolished by TTX. (D) Surface plot showing a series of power spectra constructed at regular time intervals from the data in (A). TTX first reduced then abolished the main frequency peak over a period of approximately 30 s. (E) Bar chart where frequency was measured at the latest time in the recording that a power spectrum peak could still be observed. Oscillation frequency was not affected by TTX. (F) Box plot shows the median (thick horizontal line), interquartile range (box) and range (T bars) of oscillation power. Filled circle represents an individual outlier. Oscillation power was significantly reduced by TTX (n=6). * P<0.05, Wilcoxon matched pairs signed rank test.).