We describe a simple method for computer quantification of eye movement (EM
) potentials during REM sleep. This method can be applied by investigators
using either period-amplitude (PA) or Fast Fourier Transform (FFT) spectral
EEG analysis without special hardware or computer programming. It provides
good correlations with visual ratings of EM in baseline sleep and after ad
ministration of GABAergic hypnotics. We present baseline data for both PA a
nd FFT measures for 16 normal subjects. studied for 5 consecutive nights. B
oth visually rated and computer-measured EM density (EMD) showed high night
-to-night correlations across baseline and drug nights and the computer mea
sures detected the EMD suppression that is produced by GABAergic drugs. Mea
surement of EM in addition to stage REM provides biologically significant i
nformation and application of this simple computer method. which does not r
equire pattern recognition algorithms or special hardware. could provide re
liable data that can be compared across laboratories.