title: Electrophysiological biomarkers of diagnosis and outcome in neurodevelopmental disorders.
abstract: OBJECTIVE
  The heterogeneity in clinical presentation and outcome in neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD) autism spectrum disorder (ASD) necessitates the identification and validation of biomarkers that can guide diagnosis, predict developmental outcomes, and monitor treatment response. Electrophysiology holds both practical and theoretical advantages as a clinical biomarker in neurodevelopmental disorders, and considerable effort has been invested in the search for electroencephalography (EEG) biomarkers in ADHD and ASD.
  
  
  RESULTS
  Here, we discuss the major themes in the evaluation of biomarkers and then review studies that have applied EEG to better inform diagnosis, focusing on the controversy surrounding the theta:beta ratio in ADHD; prediction of risk, highlighting recent studies of infants at high risk for ASD; and treatment monitoring, presenting new efforts in the redefinition of outcome measures in clinical trials of ASD treatment.
  
  
  CONCLUSIONS
  We conclude that insights gained from EEG studies will contribute significantly to a more mechanistic understanding of these disorders and to the development of biomarkers that can assist with diagnosis, prognosis, and intervention. There is a need, however, to utilize approaches that accommodate, rather than ignore, diagnostic heterogeneity and individual differences.
authors.affiliation: UCLA Semel Institute of Neuroscience and Human Behavior, David Geffen School of Medicine, Los Angeles, California, USA.
authors.forename: Shafali S
authors.initials: SS
authors.lastname: Jeste
authors.forename: Joel
authors.initials: J
authors.lastname: Frohlich
authors.forename: Sandra K
authors.initials: SK
authors.lastname: Loo
mesh_terms: D000818:Animals; D001289:Attention Deficit Disorder with Hyperactivity / Q000175:diagnosis* / Q000235:genetics; D015415:Biomarkers / Q000032:analysis; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis* / Q000235:genetics*; D002658:Developmental Disabilities / Q000175:diagnosis* / Q000235:genetics / Q000628:therapy*; D004569:Electroencephalography / Q000379:methods; D006801:Humans; D016896:Treatment Outcome
chemical_list: D015415:Biomarkers