Figure 8. Influence of heating on wavelet power spectra of neural and haemodynamic signals.

Wavelet power spectra of signals are compared before and during heating. Red shaded areas indicate significant effect of heating at specific frequencies and asterisks indicate significances within the frequency ranges. Skin sympathetic nerve wavelet power increased significantly during heating at low frequencies (A, inset), but muscle sympathetic nerve wavelet power (B) was not affected by heating. R-R interval, blood pressure, and skin blood flow wavelet powers were significantly increased by heating, primarily at low frequencies.