Reduced negative BOLD responses in the default-mode network and increased self-focus in depression.
OBJECTIVE
Functional imaging studies in major depressive disorder (MDD) indicate abnormal resting state neural activity and negative blood oxygenation level-dependent (BOLD) responses (NBRs) in regions of the default-mode network (DMN).


METHODS
Since activity in DMN regions has been associated with self-relatedness, we investigated neural activity in these regions during self-related emotional judgement and passive picture viewing in 25 patients with MDD and 25 healthy controls in an event-related fMRI design.


RESULTS
Behaviourally, MDD subjects showed significantly higher ratings of self-relatedness that also correlated with depression symptoms such as hopelessness. Neuroimaging results in MDD patients showed significantly lower negative BOLD responses (NBRs) in anterior medial cortical regions during judgement of self-relatedness while posterior medial regions showed increased NBRs. Unlike in healthy subjects, the anterior medial cortical NBRs were no longer parametrically modulated by the degree of self-relatedness in MDD patients.


CONCLUSIONS
Our findings suggest that reduced NBRs in the anterior regions of the default-mode network may signify decoupling from self-relatedness in MDD patients with the consecutive abnormal increase of self-focus.
Department of Psychiatry, University of Zurich, Zurich, Switzerland. simone.grimm@bli.unizh.ch
Simone
S
Grimm
Jutta
J
Ernst
Peter
P
Boesiger
Daniel
D
Schuepbach
Heinz
H
Boeker
Georg
G
Northoff
D000328:Adult; D001921:Brain / Q000503:physiopathology*; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000503:physiopathology*; D004644:Emotions / Q000502:physiology; D005260:Female; D059907:Functional Neuroimaging; D006801:Humans; D007600:Judgment / Q000502:physiology; D008279:Magnetic Resonance Imaging; D008297:Male; D009434:Neural Pathways / Q000503:physiopathology; D010775:Photic Stimulation; D012649:Self Concept