title: The variability of EEG functional connectivity of young ADHD subjects in different resting states.
abstract: OBJECTIVE
  To assess ADHD from global measures of EEG functional connectivity and their temporal variability in different resting states.
  
  
  METHODS
  EEGs from sixteen cortical regions were recorded at rest during eyes-closed (EC) and eyes-open (EO) in 10 male combined-type ADHD subjects and 12 healthy male controls. The mean global connectivity (CM) of each region and its temporal variability (CV) were estimated from a number of EEG segments recorded in both states. Connectivity indices between regions were calculated using the magnitude squared coherence (Coh) in the delta(δ)/theta(θ)/alpha(α)/beta(β) frequency bands and the nonlinear index (L) of generalized synchronization.
  
  
  RESULTS
  The CM did not present between-group differences in any region or state. However, the CV exhibited state-independent differences between both groups (ADHD>controls) mainly in frontal and parieto-occipital regions for all indices except Coh(α). Within group, only the CV-Coh(θ) of the centro-temporal region increased significantly for the ADHD subjects from EC to EO (p<0.001) and was greater than controls in EO (p<0.001).
  
  
  CONCLUSIONS
  The CV of index-L and of Coh(θ) seem to be the best state-independent and -dependent measurements, respectively, to discriminate ADHDs from control subjects using resting state EEG data.
  
  
  CONCLUSIONS
  The underlying neural dysfunctions producing the ADHD seem better reflected by the CV measurements.
authors.affiliation: Physiology Unit, Health Sciences Faculty, La Laguna University, Spain.
authors.forename: Guzmán
authors.initials: G
authors.lastname: Alba
authors.affiliation: Department of Industrial Engineering, School of Engineering and Technology, University of La Laguna, Tenerife, Spain.
authors.forename: Ernesto
authors.initials: E
authors.lastname: Pereda
authors.affiliation: Clinical Neurophysiology Unit, University Hospital La Candelaria, Tenerife, Spain.
authors.forename: Soledad
authors.initials: S
authors.lastname: Mañas
authors.affiliation: Clinical Neurophysiology Unit, University Hospital La Candelaria, Tenerife, Spain.
authors.forename: Leopoldo D
authors.initials: LD
authors.lastname: Méndez
authors.affiliation: Pediatric Unit, University Hospital N.S. La Candelaria, Tenerife, Spain.
authors.forename: Ma Rosario
authors.initials: MR
authors.lastname: Duque
authors.affiliation: Physiology Unit, Health Sciences Faculty, La Laguna University, Spain.
authors.forename: Almudena
authors.initials: A
authors.lastname: González
authors.affiliation: Physiology Unit, Health Sciences Faculty, La Laguna University, Spain. Electronic address: jugonzal@ull.edu.es.
authors.forename: Julián J
authors.initials: JJ
authors.lastname: González
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000503:physiopathology*; D002540:Cerebral Cortex / Q000503:physiopathology*; D002648:Child; D004569:Electroencephalography / Q000379:methods* / Q000592:standards; D006801:Humans; D008297:Male; D009415:Nerve Net / Q000503:physiopathology*; D015203:Reproducibility of Results; D012146:Rest / Q000502:physiology; D013997:Time Factors
keywords: ADHD; Coherence; EEG; Functional connectivity; Generalized synchronization; Resting state