Figure 1.

(A and B) FFT spectral displays, as examples of observed electrical brain activity data from two study participants. Frequency (Hz, central Y axis) is plotted against transformed amplitude (μv, X axis). Data represent one minute of data recorded from the right (T4) and left (T3) temporal montage with eyes closed at the baseline assessment. Red boxes denote the high frequency, 23–36 Hz range analyzed for temporal high-frequency electrical asymmetry. (A) is from a 14-year-old male athlete who enrolled for persisting postconcussion symptoms, primarily headache [note rightward asymmetry in the high frequencies (red box)], while (B) is from a 57-year-old female who reported a variety of symptoms, but enrolled primarily for insomnia [note leftward asymmetry in high frequencies (red box)].