Figure 8.

Power-spectrum histograms representing the mean of six consecutive samples. Black bars correspond to FFT power values computed before BF stimulation, whereas white bars are the values calculated immediately after stimulation. The differences obtained under control conditions are significant (p < 0.01) for the most prominent low ranges (1.5–6 Hz; 12–15 Hz, the spindle range, with expanded view in the inset) and high frequencies (gamma range), whereas after 7-NI, the changes evoked by BF stimulation were not significant except for 3 Hz (note, however, in this case, p < 0.05).