Abstract Introduction The relation between sleep and processing speed in youth is not fully understood. Measures of sleep health and polysomnography (PSG) may assess complementary sleep properties that have different associations with cognition. To better understand how objective and self-reported sleep relate to subdomains of processing speed in typically developing youth, we investigated associations of objective and subjective sleep measures with tests of cognitive speed and reaction time. Methods Sixty-one participants completed all study measures (Avg. Age=13 ± 3.2 years, 36 females) including one overnight PSG, cognitive measures including the Processing Speed Index (PSI; from Wechsler Intelligence Scale for Children/Wechsler Adult Intelligence Scale) and the Psychomotor Vigilance Test (PVT), and a seven-day sleep diary. From sleep diaries, we measure self-reported time in bed (dTIB, minutes) and wake after sleep onset as a measure of sleep disturbance (dWASO, minutes). From PSG, we record objective sleep duration (psgDuration, minutes) and wake after sleep onset (psgWASO, minutes). We compare objective and subjective sleep measures with PSI and PVT using Pearson correlations. We analyze the influence of age as covariate using partial correlations. Significance was defined by p-values .05. Results PSI scores were positively correlated with both dWASO (r=.27, p=.04, small effect) and psgWASO (r=.31, p=.02, small effect), but not with psgDuration (p=.21) or dTIB (p=.63). When accounting for age, PSI remained correlated with psgWASO (r=.28, p=.03, small effect), but not dWASO (r=.24, p=.07). PVT was positively correlated with dTIB (r=.45, p.01, moderate effect), although when accounting for age, this correlation did not remain significant (r=.06, p=.64). Conclusion Cognitive speed related to objective and subjective measures of sleep disturbances, but not TIB or sleep duration. In contrast, reaction time was associated only with self-reported TIB. The counterintuitive positive relation between sleep disturbances and cognitive speed could be related to the trait-like nature of the cognitive speed measure we used and is worth examining further. Overall, our findings highlight the importance of leveraging in-lab and at-home sleep measures when investigating the relationship between sleep and cognition. Support (if any) This project is supported in part by the Worthington Industries Pediatric Research Fund 2025 to PM.
Klein et al. (Fri,) studied this question.