Dentate gyrus volume and memory performance in major depressive disorder

Background: Magnetic resonance imaging (MRI) has shown lower hippocampal volume in major depressive disorder (MDD). Patients with MDD have consistently demonstrated worse performance than healthy controls a number of memory tests. Memory functions within the hippocampus in healthy younger subjects appear to be linked to cornu ammonis (CA1-3) and dentate gyrus (DG) subfields. Therefore, the main goal of the present study was to investigate whether memory deficits in MDD patients are related to reduction in hippocampal subfields volumes, particularly DG and CA 1-3. Methods: 15 MDD patients meeting DSM-IV criteria for MDD vvith moderate or severe episodes vvere recruited, together vvith 15 healthy controls. We used T2 weighted 2D Fast Spin Echo (FSE) and TlvveighLed 3D MPRAGE sequences at 4.7 T to compare hippocampal subfield volumes at 0.09 p1 voxel volume. Participants were administered the Wechsler Memory Scale. Results: MDD patients underperformed in several episodic visual memory tasks, as vvell as in visual vvorking memory, compared to healthy controls. Global hippocampal volumes were similar between groups; hovvever, MDD patients showed significantly reduced DG volumes within the hippocampal body. Duration of depression correlated with MDD patients' total volumes in the hippocampal body and CAI-3 and DG subfields within it Limitations: Our study sample was relatively small and the majority of patients were On antidepressant treatment. Conclusions: Our findings suggest that DG volumes in particular may be worthy of turthei study to further elucidate their precise role in MDD, both by itself as well as in relation to memory. (C) 2014 Elsevier B.V. All rights reserved.