Declaration of interest
N.L.N. received funding from the Institute of Mental Health, Nottingham, which enabled him to carry out this research project, and has received financial assistance to attend academic meetings from Janssen-Cilag, AstraZeneca, Servier and Shire. He has also taken part in advisory panels for Janssen-Cilag and Servier. P.F.L. has received honoraria for academic presentations from GlaxoSmithKline, AstraZeneca, Janssen-Cilag, Bristol-Myers Squibb, Eli Lilly and Johnson & Johnson Pharmaceuticals. He has also taken part in advisory panels for Eli Lilly, Pfizer and GlaxoSmithKline. G.W. has received honoraria for academic presentations from Janssen-Cilag. M.L. received a grant from the National Alliance for Research on Schizophrenia and Depression (NARSAD). L.P. has received a travel fellowship from the International Bipolar Disorder Society sponsored by Eli Lilly in 2010.
Patients in recovery following episodes of major depressive disorder (MDD) remain highly vulnerable to future recurrence. Although psychological determinants of this risk are well established, little is known about associated biological mechanisms. Recent work has implicated the default mode network (DMN) in this vulnerability but specific hypotheses remain untested within the high risk, recovered state of MDD.
To test the hypothesis that there is excessive DMN functional connectivity during task performance within recovered-state MDD and to test for connected DMN cortical gyrification abnormalities.
A multimodal structural and functional magnetic resonance imaging (fMRI) study, including task-based functional connectivity and cortical folding analysis, comparing 20 recovered-state patients with MDD with 20 matched healthy controls.
The MDD group showed significant task-based DMN hyperconnectivity, associated with hypogyrification of key DMN regions (bilateral precuneus).
This is the first evidence of connected structural and functional DMN abnormalities in recovered-state MDD, supporting recent hypotheses on biological-level vulnerability.
- Royal College of Psychiatrists