['The purpose of this study was to examine the effect of sleep deprivation on flow experience.', 'Sixteen healthy male volunteers of mean age 21.4±1.59 (21-24) years participated in two experimental conditions, ie, sleep-deprivation and normal sleep. In the sleep-deprived condition, participants stayed awake at home for 36 hours (from 8 am until 10 pm the next day) beginning on the day prior to an experimental day. In both conditions, participants carried out a simple reaction time (psychomotor vigilance) task and responded to a questionnaire measuring flow experience and mood status.', 'Flow experience was reduced after one night of total sleep deprivation. Sleep loss also decreased positive mood, increased negative mood, and decreased psychomotor performance.'] Does total sleep deprivation decrease flow experience and mood status?