title: Behavioral inhibition in childhood predicts smaller hippocampal volume in adolescent offspring of parents with panic disorder.
abstract: Behavioral inhibition (BI) is a genetically influenced behavioral profile seen in 15-20% of 2-year-old children. Children with BI are timid with people, objects and situations that are novel or unfamiliar, and are more reactive physiologically to these challenges as evidenced by higher heart rate, pupillary dilation, vocal cord tension and higher levels of cortisol. BI predisposes to the later development of anxiety, depression and substance abuse. Reduced hippocampal volumes have been observed in anxiety disorders, depression and posttraumatic stress disorder. Animal models have demonstrated that chronic stress can damage the hippocampal formation and implicated cortisol in these effects. We, therefore, hypothesized that the hippocampi of late adolescents who had been behaviorally inhibited as children would be smaller compared with those who had not been inhibited. Hippocampal volume was measured with high-resolution structural magnetic resonance imaging in 43 females and 40 males at 17 years of age who were determined to be BI+ or BI- based on behaviors observed in the laboratory as young children. BI in childhood predicted reduced hippocampal volumes in the adolescents who were offspring of parents with panic disorder, or panic disorder with comorbid major depression. We discuss genetic and environmental factors emanating from both child and parent that may explain these findings. To the best of our knowledge, this is the first study to demonstrate a relationship between the most extensively studied form of temperamentally based human trait anxiety, BI, and hippocampal structure. The reduction in hippocampal volume, as reported by us, suggests a role for the hippocampus in human trait anxiety and anxiety disorder that warrants further investigation.
authors.affiliation: 1] Developmental Neuroimaging Laboratory, Psychiatric Neuroscience Program, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA [2] Department of Psychiatry, Harvard Medical School, Boston, MA, USA [3] Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA.
authors.forename: C E
authors.initials: CE
authors.lastname: Schwartz
authors.affiliation: Developmental Neuroimaging Laboratory, Psychiatric Neuroscience Program, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: P S
authors.initials: PS
authors.lastname: Kunwar
authors.affiliation: 1] Department of Psychiatry, Harvard Medical School, Boston, MA, USA [2] Pediatric Psychopharmacology Unit, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: D R
authors.initials: DR
authors.lastname: Hirshfeld-Becker
authors.affiliation: 1] Department of Psychiatry, Harvard Medical School, Boston, MA, USA [2] Pediatric Psychopharmacology Unit, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: A
authors.initials: A
authors.lastname: Henin
authors.affiliation: Athinoula A. Martinos Center for Biomedical Imaging, Charlestown, MA, USA.
authors.forename: M G
authors.initials: MG
authors.lastname: Vangel
authors.affiliation: 1] Department of Psychiatry, Harvard Medical School, Boston, MA, USA [2] Department of Psychiatry, McLean Hospital, Belmont, MA, USA.
authors.forename: S L
authors.initials: SL
authors.lastname: Rauch
authors.affiliation: 1] Department of Psychiatry, Harvard Medical School, Boston, MA, USA [2] Pediatric Psychopharmacology Unit, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Biederman
authors.affiliation: 1] Department of Psychiatry, Harvard Medical School, Boston, MA, USA [2] Pediatric Psychopharmacology Unit, Department of Psychiatry, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: J F
authors.initials: JF
authors.lastname: Rosenbaum
mesh_terms: D000293:Adolescent; D001007:Anxiety / Q000473:pathology*; D016241:Child of Impaired Parents / Q000523:psychology*; D002675:Child, Preschool; D003865:Major Depressive Disorder / Q000235:genetics; D005260:Female; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D059906:Neuroimaging; D009929:Organ Size; D016584:Panic Disorder / Q000235:genetics*