In a 13-night sleep laboratory study, each of 18 normal young adult males twice received 1 cup of warm water, 1-, 2-, and 4-cup equivalents of regular coffee, a 4-cup equivalent of decaffeinated coffee, and a 4-cup equivalent of caffeine. All beverages were administered 30 min before bedtime according to a balanced Latin-square design. Regular coffee produced dose-related changes in most standard electroencephalogram-electrooculogram (EEG-EOG) sleep parameters, and the 4-cup equivalents of regular coffee and caffeine produced equivalent effects. Decaffeinated coffee had no effect. Regular coffee and caffeine caused rapid eye movement (REM) sleep to shift to the early part of the night and stages 3 and 4 sleep to shift to the later part. Coffee also produced dose-related changes in several subjects estimates of sleep characteristics. These results suggest that coffee and caffeine may be used in normal subjects to induce symptoms mimicking those of insomnia. Such a tool should promote further understanding of insomnia.

No abstract

No abstract

No abstract

Thirty-two male patients complaining of impotence were administered the Male Impotence Test (MIT) and the Minnesota Multiphasic Personality Inventory (MMPI). Subsequently, the tumescence of these patients was recorded for 1-3 nights in the Baylor College of Medicine sleep laboratory. An attempt was made to evaluate the predictive validity of the MIT and the MMPI in discriminating between those who produced normal penile tumescence during sleep and those who did not. Indication of normal nocturnal tumescence was taken to indicate the physiological capacity for achieving arousal and hence was suggestive of psychogenic impotence. The results suggested that the MIT is without value for differentiating between psychogenic and biogenic impotence, whereas two rules from the MMPI appropriately classified 90% of the cases. The samples of biogenic and psychogenic impotence did not differ, however, in degree or pathology nor was there any specific profile related to either condition.