title: Early adolescent cognitive gains are marked by increased sleep EEG coherence.
abstract: Although the increases in cognitive capacities of adolescent humans are concurrent with significant cortical restructuring, functional associations between these phenomena are unclear. We examined the association between cortical development, as measured by the sleep EEG, and cognitive performance in a sample of 9/10 year olds followed up 1 to 3 years later. Our cognitive measures included a response inhibition task (Stroop), an executive control task (Trail Making), and a verbal fluency task (FAS). We correlated sleep EEG measures of power and intra-hemispheric coherence at the initial assessment with performance at that assessment. In addition we correlated the rate of change across assessments in sleep EEG measures with the rate of change in performance. We found no correlation between sleep EEG power and performance on cognitive tasks for the initial assessment. In contrast, we found a significant correlation of the rate of change in intra-hemispheric coherence for the sigma band (11 to 16 Hz) with rate of change in performance on the Stroop (r = 0.61; p<0.02) and Trail Making (r =  -0.51; p<0.02) but no association for the FAS. Thus, plastic changes in connectivity (i.e., sleep EEG coherence) were associated with improvement in complex cognitive function.
authors.affiliation: University Hospital of Child and Adolescent Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland; Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland; Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America.
authors.forename: Leila
authors.initials: L
authors.lastname: Tarokh
authors.affiliation: Department of Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, Rhode Island, United States of America; Centre for Sleep Research, School of Psychology, Social Work and Social Policy, University of South Australia, Adelaide, Australia.
authors.forename: Mary A
authors.initials: MA
authors.lastname: Carskadon
authors.affiliation: Institute of Pharmacology and Toxicology, University of Zurich, Zurich, Switzerland; Zurich Center for Integrative Human Physiology, University of Zurich, Zurich, Switzerland; Neuroscience Center, University and ETH Zurich, Zurich, Switzerland; Zurich Center for Interdisciplinary Sleep Research, University of Zurich, Zurich, Switzerland.
authors.forename: Peter
authors.initials: P
authors.lastname: Achermann
mesh_terms: D000293:Adolescent; D002648:Child; D003071:Cognition / Q000502:physiology*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D012890:Sleep / Q000502:physiology*; D013997:Time Factors