title: Individual differences in childhood sleep problems predict later cognitive executive control.
abstract: OBJECTIVE
  To determine whether individual differences in developmental patterns of general sleep problems are associated with 3 executive function abilities-inhibiting, updating working memory, and task shifting-in late adolescence.
  
  
  METHODS
  916 twins (465 female, 451 male) and parents from the Colorado Longitudinal Twin Study.
  
  
  RESULTS
  Parents reported their children's sleep problems at ages 4 years, 5 y, 7 y, and 9-16 y based on a 7-item scale from the Child-Behavior Checklist; a subset of children (n = 568) completed laboratory assessments of executive functions at age 17. Latent variable growth curve analyses were used to model individual differences in longitudinal trajectories of childhood sleep problems. Sleep problems declined over time, with approximately 70% of children having > or = 1 problem at age 4 and approximately 33% of children at age 16. However, significant individual differences in both the initial levels of problems (intercept) and changes across time (slope) were observed. When executive function latent variables were added to the model, the intercept did not significantly correlate with the later executive function latent variables; however, the slope variable significantly (P < 0.05) negatively correlated with inhibiting (r = -0.27) and updating (r = -0.21), but not shifting (r = -0.10) abilities. Further analyses suggested that the slope variable predicted the variance common to the 3 executive functions (r = -0.29).
  
  
  CONCLUSIONS
  Early levels of sleep problems do not seem to have appreciable implications for later executive functioning. However, individuals whose sleep problems decrease more across time show better general executive control in late adolescence.
authors.affiliation: Institute for Behavioral Genetics, University of Colorado at Boulder Boulder CO 80309, USA. naomi.friedman@colorado.edu
authors.forename: Naomi P
authors.initials: NP
authors.lastname: Friedman
authors.forename: Robin P
authors.initials: RP
authors.lastname: Corley
authors.forename: John K
authors.initials: JK
authors.lastname: Hewitt
authors.forename: Kenneth P
authors.initials: KP
authors.lastname: Wright
mesh_terms: D000293:Adolescent; D001288:Attention / Q000502:physiology; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D004200:Diseases in Twins / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D006801:Humans; D007206:Individuality; D007266:Inhibition, Psychological; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology; D009483:Neuropsychological Tests / Q000706:statistics & numerical data; D017397:Prefrontal Cortex / Q000503:physiopathology; D011340:Problem Solving / Q000502:physiology; D011594:Psychometrics; D012893:Sleep Wake Disorders / Q000503:physiopathology / Q000523:psychology*