Figure 1
From: Coincident frequencies and relative phases among brain activity and hormonal signals
Intensity of the different brain signals superimposed to hormone level signals. The horizontal scale is 2π/28 days-1. The vertical scale has normalized arbitrary units. It is shown period coincidences and relative intensities in different points; when the peaks agree and both are bigger than 1/3 the coincidences were taken into account for this analysis, considering the smaller peaks as noise generated from the discrete Fourier transform.