Hippocampal and amygdalar volumes in dissociative identity disorder.
OBJECTIVE
Smaller hippocampal volume has been reported in several stress-related psychiatric disorders, including posttraumatic stress disorder (PTSD), borderline personality disorder with early abuse, and depression with early abuse. Patients with borderline personality disorder and early abuse have also been found to have smaller amygdalar volume. The authors examined hippocampal and amygdalar volumes in patients with dissociative identity disorder, a disorder that has been associated with a history of severe childhood trauma.


METHODS
The authors used magnetic resonance imaging to measure the volumes of the hippocampus and amygdala in 15 female patients with dissociative identity disorder and 23 female subjects without dissociative identity disorder or any other psychiatric disorder. The volumetric measurements for the two groups were compared.


RESULTS
Hippocampal volume was 19.2% smaller and amygdalar volume was 31.6% smaller in the patients with dissociative identity disorder, compared to the healthy subjects. The ratio of hippocampal volume to amygdalar volume was significantly different between groups.


CONCLUSIONS
The findings are consistent with the presence of smaller hippocampal and amygdalar volumes in patients with dissociative identity disorder, compared with healthy subjects.
Vermetten
Eric
E
Department of Psychiatry, Rudolf Magnus Institute of Neurosciences, University Medical Center, Int mailbox B01206, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands. e.vermetten@umcutrecht.nl
Schmahl
Christian
C
Lindner
Sanneke
S
Loewenstein
Richard J
RJ
Bremner
J Douglas
JD
D000328:Adult; D000679:Amygdala / Q000033:anatomy & histology* / Q000473:pathology*; D001284:Atrophy / Q000473:pathology; D002648:Child; D002649:Child Abuse / Q000175:diagnosis / Q000706:statistics & numerical data; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology; D009105:Dissociative Identity Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology*; D005260:Female; D007839:Functional Laterality; D006624:Hippocampus / Q000033:anatomy & histology* / Q000473:pathology*; D006801:Humans; D008279:Magnetic Resonance Imaging; D011569:Psychiatric Status Rating Scales; D012737:Sex Factors; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis / Q000453:epidemiology