Abnormal hippocampal structure and function in clinical anxiety and comorbid depression
Abstract
Given the high prevalence rates of comorbidity of anxiety and depressive disorders, identifying a common neural pathway to both disorders is important not only for better diagnosis and treatment, but also for a more complete conceptualization of each disease. Hippocampal abnormalities have been implicated in anxiety and depression, separately; however, it remains unknown whether these abnormalities are also implicated in their comorbidity. Here we address this question by testing 32 adults with generalized anxiety disorder (15 GAD only and 17 comorbid MDD) and 25 healthy controls (HC) using multimodal MRI (structure, diffusion and functional) and automated hippocampal segmentation. We demonstrate that (i) abnormal microstructure of the CA1 and CA2‐3 is associated with GAD/MDD comorbidity and (ii) decreased anterior hippocampal reactivity in response to repetition of the threat cue is associated with GAD (with or without MDD comorbidity). In addition, mediation‐structural equation modeling (SEM) reveals that our hippocampal and dimensional symptom data are best explained by a model describing a significant influence of abnormal hippocampal microstructure on both anxiety and depression—mediated through its impact on abnormal hippocampal threat processing. Collectively, our findings show a strong association between changes in hippocampal microstructure and threat processing, which together may present a common neural pathway to comorbidity of anxiety and depression. © 2016 Wiley Periodicals, Inc.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Feb 16, 2016
- Source ID
- 10.1002/hipo.22566
Entities
People
- Helen Blair Simpson
- Inkyung Song
- Jiook Cha
- Jonathan Posner
- Lilianne R. Mujica‐parodi
- Tsafrir Greenberg
Organizations
- Columbia University
- Office of Naval Research
- Stony Brook University