Fig. 10
From: Sleep alterations as a function of 88 health indicators
The correlation between PSD and zolpidem/benzodiazepine use. Axis Y shows the point-biserial correlation between health indicators and sleep EEG PSD. Correlations significant after correction for multiple comparisons are marked with a dot in the appropriate color above the lines. Note that a NREM-specific increase in sigma activity is associated with the use of these medications, but it was accompanied by reductions in low-frequency and increases in high-frequency activity in benzodiazepine users only