Time series and power spectrum of PTSD subjects.

<p>(A) The time series of three individual subjects, (B) concatenated time series of the three individual time series, and (C) amplitude spectrum of the time series. The height of dominant peak in the spectrum is denoted by h, and is the difference in the frequency of the time series corresponding to the full width at half maximum (FWHM, given as exp(−1/2)* <i>h</i>), is the background noise. The fundamental frequency of the concatenated time series is 0.0417 Hz and this corresponds to the frequency where maximum peak “h” occur in the spectrum.