Rose or black-coloured glasses? Altered neural processing of positive events during memory formation is a trait marker of depression.
BACKGROUND
Valence-specific memory enhancement is one of the core cognitive functions that causes and maintains Major Depressive Disorder (MDD). While previous neuroimaging studies have elucidated the neural underpinnings of this emotional enhancement effect in depressed patients, this study aimed at detecting processing biases that are maintained throughout remission while patients were euthymic.


METHODS
Fourteen medication-free women remitted from unipolar MDD and 14 matched controls were scanned while learning negative, positive, and neutral words, which were subsequently tested with free recall.


RESULTS
The two groups did not differ in memory performance and showed no neural differences during successful encoding of neutral or negative words. However, during successful encoding of positive words, patients exhibited a larger recruitment of a set of areas, comprising cingulate gyrus, right inferior- and left medial-frontal gyrus as well as the right anterior hippocampus/amygdala.


CONCLUSIONS
Restriction to female participants may limit the generalization of the findings.


CONCLUSIONS
Female MDD patients in clinical remission exert greater neural recruitment of memory-related brain regions when successfully encoding positive words, suggesting that neural biases related to memory formation of positive information do not entirely normalize. Further research is needed to establish whether this processing bias during successful memory formation of positive information is predictive for future relapse thereby offering the possibility to develop more focused therapeutic interventions to specifically target these processes.
Radboud University Nijmegen Medical Centre, Department of Psychiatry, The Netherlands. J.Arnold@donders.ru.nl
Jennifer F
JF
Arnold
Daniel A
DA
Fitzgerald
Guillen
G
Fernández
Mark
M
Rijpkema
Mike
M
Rinck
Paul A T M
PA
Eling
Eni S
ES
Becker
Anne
A
Speckens
Indira
I
Tendolkar
D000328:Adult; D001921:Brain / Q000503:physiopathology; D016022:Case-Control Studies; D003865:Major Depressive Disorder / Q000503:physiopathology / Q000523:psychology*; D005260:Female; D006801:Humans; D007406:Interview, Psychological; D008279:Magnetic Resonance Imaging; D008568:Memory / Q000502:physiology*; D011939:Mental Recall / Q000502:physiology; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011999:Recruitment, Neurophysiological / Q000502:physiology