• Application of automated rapid-eye-movement (REM) analysis can characterize individual REM periods in depressed patients. Average REM count for the individual REM periods generally demonstrated considerable decreases in the second half of the REM period and differentiated patients who subsequently did not respond well to tricyclic antidepressants. These findings suggest that, even as late as six hours into a night of sleep, significant differences among depressed patients are present, based on treatment responder groups. Furthermore, a reevaluation of the previous emphasis on REM abnormalities in the first hour or two of the night may be indicated.
Kupfer DJ, Shaw DH, Ulrich R, Coble PA, Spiker DG. Application of Automated REM Analysis in Depression. Arch Gen Psychiatry. 1982;39(5):569-573. doi:10.1001/archpsyc.1982.04290050045009