Lt. Van Elst et al., Amygdala enlargement in dysthymia - A volumetric study of patients with temporal lobe epilepsy, BIOL PSYCHI, 46(12), 1999, pp. 1614-1623
Background: Previous studies indicated an important role of the amygdala fo
r 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 hea
lthy 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 amygd
ala 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 am
ygdala volumes and depression (p = .06), as measured with the Beck Depressi
on Inventory. Amygdala volumes of females were significantly larger than th
ose of males (left side: p = .005; right side: p = .06).
Conclusions: This is the second report afa relationship between amygdala vo
lumes and depressed mood, confirming an earlier finding in patients with bi
polar disease, and the first study reporting a correlation between amygdala
volumes and depression. Increased processing of emotional information migh
t increase amygdala blood flow and subsequently, result in amygdala enlarge
ment. Biol Psychiatry 1999;46:1614-1623 (C) 1999 Society of Biological Psyc
hiatry.