title: Developmental change in amygdala reactivity during adolescence: effects of family history of depression and stressful life events.
abstract: OBJECTIVE
  Although heightened amygdala reactivity is observed in patients with major depression, two critical gaps in our knowledge remain. First, it is unclear whether heightened amygdala reactivity is a premorbid vulnerability or a consequence of the disorder. Second, it is unknown how and when this neural phenotype develops. The authors sought to address these gaps by evaluating developmental change in threat-related amygdala reactivity in adolescents at high or low risk for depression based on family history, before onset of disorder.
  
  
  METHODS
  At baseline and again 2 years later, adolescents (initially 11-15 years of age) participated in a functional MRI paradigm that elicited threat-related amygdala reactivity. After quality control, data were available for 232 adolescents at wave 1 and 197 adolescents at wave 2; longitudinal data meeting quality control at both waves were available for 157 of these participants. Change in amygdala reactivity was assessed as a function of family history of depression and severity of stressful life events.
  
  
  RESULTS
  Threat-related amygdala reactivity increased with age in participants with a positive family history regardless of the severity of life stress reported, and it increased in adolescents with a negative family history who reported relatively severe life stress. These changes in amygdala reactivity with age occurred in the absence of clinical disorder or increases in depressive symptoms.
  
  
  CONCLUSIONS
  These results suggest that heightened amygdala reactivity emerges during adolescence, prior to the development of depression, as a function of familial risk or, in the absence of familial risk, stressful life events.
authors.affiliation: From the Center for Developmental Science, University of North Carolina at Chapel Hill; the Department of Psychology and Neuroscience and the Institute for Genome Sciences and Policy, Duke University, Durham, N.C.; and the Translational Epidemiology Program, Department of Psychiatry, University of Texas Health Sciences Center at San Antonio.
authors.forename: Johnna R
authors.initials: JR
authors.lastname: Swartz
authors.forename: Douglas E
authors.initials: DE
authors.lastname: Williamson
authors.forename: Ahmad R
authors.initials: AR
authors.lastname: Hariri
mesh_terms: D000293:Adolescent; D000679:Amygdala / Q000473:pathology / Q000503:physiopathology; D003866:Depressive Disorder / Q000175:diagnosis / Q000503:physiopathology / Q000523:psychology; D005190:Family; D005260:Female; D006801:Humans; D008016:Life Change Events; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D011580:Psychological Techniques; D011599:Psychopathology; D018570:Risk Assessment; D012307:Risk Factors; D013315:Stress, Psychological / Q000150:complications*