Autobiographical deficits correlate with gray matter volume in depressed and high risk participants

Autobiographical memory (AM) overgenerality is a consistent neuropsychological feature of major depressive disorder (MDD) and is present in individuals at high-familial risk (HR) of developing MDD. Structural changes have been found in brain regions implicated in AM recall in MDDs and HRs. However, the relationship between selective regional gray matter volume (GMV) differences and AM recall deficits has not been examined. We examined this relationship in 27 HR, 43 unmedicated MDD and 47 low-risk healthy control participants as they completed an AM task during functional magnetic resonance imaging. FreeSurfer was used for automated anatomical image processing and volumetric quantification. Anatomical regions of interest for GMV analysis were selected based on regions most commonly activated in controls as they recall specific AMs according to a recent meta-analysis. Pearson correlations were calculated among volumetric and AM recall data. In HRs and MDDs, left hippocampal volume correlated positively with specific (HRs r = 0.42; MDDs r = 0.60) and inversely with categorical AM recall (HRs r = -0.51; MDDs r = -0.35). In MDDs, left precuneus volume also correlated positively with specific (r = 0.49) and inversely with categorical (r = -0.35) AM recall. Our results suggest selective GMV alterations within the AM network may contribute to AM impairments observed in both HR and MDD individuals.