Representation of sleep stages by color density spectral array.

Multiple-channel color density spectral array (CDSA) was used to graphically represent sleep stages. This technique uses color coding of Fast Fourier Transforms to provide a compact display of frequency, power, and real time. Distinct CDSA patterns correlate to the awake, non-REM, and REM sleep states. The graphic compression of sleep data could considerably shorten the time required to stage overnight sleep recordings.