The effects of caffeine, dextroamphetamine, and modafinil on humor appreciation during sleep deprivation.
OBJECTIVE
Sleep loss consistently impairs performance on measures of alertness, vigilance, and response speed, but its effects on higher-order executive functions are not well delineated. Similarly, whereas deficits in arousal and vigilance can be temporarily countered by the use of several different stimulant medications, it is not clear how these compounds affect complex cognitive processes in sleep-deprived individuals.


METHODS
We evaluated the effects of double-blind administration of 3 stimulant medications or placebo on the ability to appreciate humor in visual (cartoons) or verbal (headlines) stimuli presented on a computer screen following 49.5 hours of sleep deprivation.


METHODS
In-residence sleep-laboratory facility at the Walter Reed Army Institute of Research.


METHODS
Fifty-four healthy adults (29 men, 24 women), ranging in age from 18 to 36 years.


METHODS
Each participant was randomly assigned to 1 of 3 stimulant medication groups, including caffeine, 600 mg, n = 12; modafinil, 400 mg, n = 11; dextroamphetamine, 20 mg, n = 16; or placebo, n = 14.


RESULTS
Humor appreciation for cartoon stimuli was enhanced by modafinil relative to both placebo and caffeine, but there was no effect of any stimulant medication on the appreciation of verbal humor during sleep loss. In contrast, all 3 stimulants improved psychomotor response speed, whereas only caffeine and dextroamphetamine improved ratings of subjective sleepiness.


CONCLUSIONS
Findings suggest that, despite similar alerting and vigilance-promoting effects, these 3 compounds have significantly different effects on those highly complex cognitive abilities mediated by the pre-frontal cortex.
Killgore
William D S
WD
Division of Neuroscience, Department of Behavioral Biology, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA. william.d.killgore@us.army.mil
McBride
Sharon A
SA
Killgore
Desiree B
DB
Balkin
Thomas J
TJ
D000293:Adolescent; D000328:Adult; D001559:Benzhydryl Compounds / Q000494:pharmacology* / Q000627:therapeutic use; D002110:Caffeine / Q000494:pharmacology* / Q000627:therapeutic use; D000697:Central Nervous System Stimulants / Q000494:pharmacology* / Q000627:therapeutic use; D003071:Cognition / Q000187:drug effects*; D003913:Dextroamphetamine / Q000494:pharmacology* / Q000627:therapeutic use; D006970:Disorders of Excessive Somnolence / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D000077408:Modafinil; D011581:Psychological Tests; D011595:Psychomotor Agitation / Q000175:diagnosis; D012892:Sleep Deprivation / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology; D014925:Wit and Humor as Topic
D001559:Benzhydryl Compounds; D000697:Central Nervous System Stimulants; D002110:Caffeine; D000077408:Modafinil; D003913:Dextroamphetamine