Impairment of reaction time among children awakened during stage 4 sleep

Abstract

Study Objective: Sleep inertia refers to impairments in cognitive/motor performance and the tendency to return to sleep after awakening. As part of a project studying the effect of different types of 100 decibel (dB) sounds on awakening children during stage 4 sleep (S4S), we hypothesized that children with the greatest impairment in auditory arousal during S4S, manifested by the inability to either awaken to 100 dB sounds or successfully perform a self-rescue sequence (SRS), would have greater impairments in reaction time (RT) upon awakening than children who awoke and successfully accomplish a SRS. Design: Observational study Setting: Pediatric hospital-based sleep center Participants: Healthy children aged 6-12 years Interventions: N/A Measurements and Results: RT was measured in 44 children approximately 90 minutes before bedtime and again after awakening by either 100 dB alarms or manually during the first and second cycles of S4S. Overall, mean and median RT slowed significantly by 37% and 22%, respectively, from baseline. Slowing of RT was most evident in the youngest children (aged 6-7 years) and after awakening from the second S4S cycle. Impairments in RT were not significantly different among children who successfully awakened to the alarm and performed a SRS compared with children who did not. Conclusions: The degree of slowing of RT was not significantly different among children who awakened and performed an SRS compared with children who did not. The greatest slowing of RT was seen among younger children and after awakening from the second S4S cycle.