Hippocampus and amygdala morphology in attention-deficit/hyperactivity disorder

Kerstin J. Plessen, Ravi Bansal, Hongtu Zhu, Ronald Whiteman, Jose Amat, Georgette A. Quackenbush, Laura Martin, Kathleen Durkin, Clancy Blair, Jason Royal, Kenneth Hugdahl, Bradley S. Peterson

Research output: Contribution to journalArticlepeer-review


Context: Limbic structures are implicated in the genesis of attention-deficit/hyperactivity disorder (ADHD) by the presence of mood and cognitive disturbances in affected individuals and by elevated rates of mood disorders in family members of probands with ADHD. Objective: To study the morphology of the hippocampus and amygdala in children with ADHD. Design: A cross-sectional case-control study of the hippocampus and amygdala using anatomical magnetic resonance imaging. Settings: University research institute. Patients: One hundred fourteen individuals aged 6 to 18 years, 51 with combined-type ADHD and 63 healthy controls. Main Outcome Measures: Volumes and measures of surface morphology for the hippocampus and amygdala. Results: The hippocampus was larger bilaterally in the ADHD group than in the control group (t=3.35; P<.002). Detailed surface analyses of the hippocampus further localized these differences to an enlarged head of the hippocampus in the ADHD group. Although conventional measures did not detect significant differences in amygdalar volumes, surface analyses indicated the presence of reduced size bilaterally over the area of the basolateral complex. Correlations with prefrontal measures suggested abnormal connectivity between the amygdala and prefrontal cortex in the ADHD group. Enlarged subregions of the hippocampus tended to accompany fewer symptoms. Conclusions: The enlarged hippocampus in children and adolescents with ADHD may represent a compensatory response to the presence of disturbances in the perception of time, temporal processing (eg, delay aversion), and stimulus seeking associated with ADHD. Disrupted connections between the amygdala and orbitofrontal cortex may contribute to behavioral disinhibition. Our findings suggest involvement of the limbic system in the pathophysiology of ADHD.

Original languageEnglish (US)
Pages (from-to)795-807
Number of pages13
JournalArchives of General Psychiatry
Issue number7
StatePublished - 2006

ASJC Scopus subject areas

  • Arts and Humanities (miscellaneous)
  • Psychiatry and Mental health


Dive into the research topics of 'Hippocampus and amygdala morphology in attention-deficit/hyperactivity disorder'. Together they form a unique fingerprint.

Cite this