title: Development of brain synchronisation within school-age--individual analysis of resting (α) coherence in a longitudinal data set.
abstract: OBJECTIVE
  Given evidence that synchronisation of neuronal activity may be a correlate of cognition, we examined EEG coherence as function of age and inter-electrode distance in healthy children and adolescents in order to elucidate basic information for a better understanding of developmental disorders associated with deficits in cognitive functions.
  
  
  METHODS
  Based on a 64-channel eyes closed resting EEG we combined local and global coherence measures in order to reduce volume conduction and reference effects. We used a two point longitudinal design in order to analyze intraindividual change during school-age (n=40; 6-18 years). Coherence was analyzed within individually adjusted frequency bands and around iPF (= individual alpha peak frequency).
  
  
  RESULTS
  Both local and global resting coherence was largest in the alpha range and particularly around iPF. Local synchronisation was larger in the left compared with the right hemisphere. Controlling for increases in iPF, synchronisation increased with age, with global changes being most pronounced in the alpha range. Moreover age-related changes suggest an earlier development in girls.
  
  
  CONCLUSIONS
  Our data provides evidence that both local and global functional integration increases during normal development within school-age.
  
  
  CONCLUSIONS
  This general pattern - combined with more specific effects of sex and frequency - may help to specify deviations in developmental disorders.
authors.affiliation: Section of Experimental Psychopathology and Neurophysiology, Department of Psychiatry, University of Heidelberg, Germany. Dennis.Gmehlin@med.uni-heidelberg.de
authors.forename: Dennis
authors.initials: D
authors.lastname: Gmehlin
authors.forename: Christine
authors.initials: C
authors.lastname: Thomas
authors.forename: Matthias
authors.initials: M
authors.lastname: Weisbrod
authors.forename: Stephan
authors.initials: S
authors.lastname: Walther
authors.forename: Franz
authors.initials: F
authors.lastname: Resch
authors.forename: Rieke
authors.initials: R
authors.lastname: Oelkers-Ax
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000513:Alpha Rhythm / Q000502:physiology*; D001921:Brain / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology*; D002648:Child; D003344:Cortical Synchronization / Q000502:physiology*; D003430:Cross-Sectional Studies; D004569:Electroencephalography / Q000379:methods; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D012146:Rest / Q000502:physiology*; D013334:Students