1. ¹Department of Psychiatry, Mount Sinai School of Medicine, New York, NY, USA
2. ²Department of Psychiatry, Mount Sinai School of Medicine, Bronx VA Medical Center, Bronx, NY, USA
3. ³Department of Psychiatry and Neuroscience PET Laboratory, Mount Sinai School of Medicine, New York, NY, USA

Correspondence: Dr AS New, Department of Psychiatry, Mount Sinai School of Medicine, Box 1218, One Gustave Levy Place, New York, NY 10029, USA. Tel: +1 212 241 0193, Fax: +1 212 824 2302, E-mail: antonia.new@mssm.edu

Received 7 March 2006; Revised 26 September 2006; Accepted 2 October 2006; Published online 3 January 2007.

Abstract

Abnormal fronto-amygdala circuitry has been implicated in impulsive aggression, a core symptom of borderline personality disorder (BPD). We examined relative glucose metabolic rate (rGMR) at rest and after m-CPP (meta-chloropiperazine) with ¹⁸fluorodeoxyglucose (FDG) with positron emission tomography (PET) in 26 impulsive aggressive (IED)-BPD patients and 24 controls. Brain edges/amygdala were visually traced on MRI scans co-registered to PET scans; rGMR was obtained for ventral and dorsal regions of the amygdala and Brodmann areas within the prefrontal cortex (PFC). Correlation coefficients were calculated between rGMR for dorsal/ventral amygdala regions and PFC. Additionally, amygdala volumes and rGMR were examined in BPD and controls. Correlations PFC/amygdala Placebo: Controls showed significant positive correlations between right orbitofrontal (OFC) and ventral, but not dorsal, amygdala. Patients showed only weak correlations between amygdala and the anterior PFC, with no distinction between dorsal and ventral amygdala. Correlations PFC/amygdala: m-CPP response: Controls showed positive correlations between OFC and amygdala regions, whereas patients showed positive correlations between dorsolateral PFC and amygdala. Group differences between interregional correlational matrices were highly significant. Amygdala volume/metabolism: No group differences were found for amygdala volume, or metabolism in the placebo condition or in response to meta-chloropiperazine (m-CPP). We demonstrated a tight coupling of metabolic activity between right OFC and ventral amygdala in healthy subjects with dorsoventral differences in amygdala circuitry, not present in IED-BPD. We demonstrated no significant differences in amygdala volumes or metabolism between BPD patients and controls.