Amygdala enlargement in dysthymia--a volumetric study of patients with temporal lobe epilepsy

Biol Psychiatry. 1999 Dec 15;46(12):1614-23. doi: 10.1016/s0006-3223(99)00212-7.


Background: Previous studies indicated an important role of the amygdala for emotional information processing. We investigated a possible relationship between amygdala volumes, aggressive behavior, and dysthymia, in patients with temporal lobe epilepsy (TLE).

Methods: Patients with TLE with and without aggression or dysthymia and healthy volunteers were assessed using quantitative MRI. Amygdala volumes were measured in a blinded fashion and corrected for total brain volumes.

Results: There was a highly significant enlargement of left and right amygdala volumes in patients with dysthymia (right side, p < .000; left side, p = .001). We found a significant positive correlation between left amygdala volumes (p = .02) and a trend towards positive correlation between right amygdala volumes and depression (p = .06), as measured with the Beck Depression Inventory. Amygdala volumes of females were significantly larger than those of males (left side: p = .005; right side: p = .06).

Conclusions: This is the second report of a relationship between amygdala volumes and depressed mood, confirming an earlier finding in patients with bipolar disease, and the first study reporting a correlation between amygdala volumes and depression. Increased processing of emotional information might increase amygdala blood flow and subsequently, result in amygdala enlargement.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aggression*
  • Amygdala / pathology*
  • Analysis of Variance
  • Case-Control Studies
  • Depression / pathology
  • Disruptive, Impulse Control, and Conduct Disorders / etiology
  • Disruptive, Impulse Control, and Conduct Disorders / pathology*
  • Dominance, Cerebral
  • Dysthymic Disorder / complications*
  • Dysthymic Disorder / pathology*
  • Epilepsy, Temporal Lobe / complications*
  • Epilepsy, Temporal Lobe / pathology*
  • Female
  • Humans
  • Magnetic Resonance Imaging
  • Male
  • Middle Aged
  • Psychiatric Status Rating Scales