Effect of sleep extension on sluggish cognitive tempo symptoms and driving behavior in adolescents with chronic short sleep

Objective/background: Few adolescents report obtaining adequate amounts of sleep. Correlational studies have linked adolescent short sleep with driving crashes and sluggish cognitive tempo (SCT), a cluster of symptoms that include sluggishness and low persistence that are related to but distinct from inattention and sleepiness. The relationship between SCT and driving is understudied, and no study has experimentally examined the relationship between SCT and sleep. We examined the relationship between SCT and driving problems in a sample of chronically short-sleeping adolescents. We also examined whether experimentally extending sleep improved SCT and driving behaviors.

Participants/methods: Licensed 16- to 18-year-old adolescents who regularly obtained five to seven hours of sleep completed a five-week at-home experimental protocol: a baseline week to determine typical sleep (TYP), followed in a counterbalanced order by two-week spans in which school-night bedtimes and rise times were (a) matched to TYP or (b) modified to extend (EXT) time in bed by 1.5 h/night. Sleep was monitored by actigraphy. Self- and parent-reported SCT and inattention and self-reported driving problems were recorded at baseline and following each condition. Of the 38 eligible participants who completed the baseline session, 24 completed all five weeks of the protocol.

Results: After controlling for inattention, only parent-reported SCT was significantly positively associated with self-reported purposeful driving violations at baseline. Adolescents reported lesser SCT during EXT than during TYP. Further, after controlling for inattention, participants who reported improvement in SCT demonstrated fewer driving problems during EXT than during TYP.

Conclusions: Preliminary findings suggest that extending sleep in short-sleeping adolescents may help alleviate SCT symptoms and improve driving.