Persistent non-verbal memory impairment in remitted major depression - caused by encoding deficits?
BACKGROUND
While neuropsychological impairments are well described in acute phases of major depressive disorders (MDD), little is known about the neuropsychological profile in remission. There is evidence for episodic memory impairments in both acute depressed and remitted patients with MDD. Learning and memory depend on individuals' ability to organize information during learning. This study investigates non-verbal memory functions in remitted MDD and whether nonverbal memory performance is mediated by organizational strategies whilst learning.


METHODS
30 well-characterized fully remitted individuals with unipolar MDD and 30 healthy controls matching in age, sex and education were investigated. Non-verbal learning and memory were measured by the Rey-Osterrieth-Complex-Figure-Test (RCFT). The RCFT provides measures of planning, organizational skills, perceptual and non-verbal memory functions. For assessing the mediating effects of organizational strategies, we used the Savage Organizational Score.


RESULTS
Compared to healthy controls, participants with remitted MDD showed more deficits in their non-verbal memory function. Moreover, participants with remitted MDD demonstrated difficulties in organizing non-verbal information appropriately during learning. In contrast, no impairments regarding visual-spatial functions in remitted MDD were observed.


CONCLUSIONS
Except for one patient, all the others were taking psychopharmacological medication. The neuropsychological function was solely investigated in the remitted phase of MDD.


CONCLUSIONS
Individuals with MDD in remission showed persistent non-verbal memory impairments, modulated by a deficient use of organizational strategies during encoding. Therefore, our results strongly argue for additional therapeutic interventions in order to improve these remaining deficits in cognitive function.
Behnken
Andreas
A
Department of Psychiatry and Psychotherapy, University of Muenster, Albert-Schweitzer-Str. 11, 48149 Muenster, Germany. abehnken@uni-muenster.de
Schöning
Sonja
S
Gerss
Joachim
J
Konrad
Carsten
C
de Jong-Meyer
Renate
R
Zwanzger
Peter
P
Arolt
Volker
V
D000328:Adult; D001288:Attention; D003865:Major Depressive Disorder / Q000175:diagnosis* / Q000523:psychology; D056344:Executive Function; D005260:Female; D006801:Humans; D008297:Male; D008569:Memory Disorders / Q000175:diagnosis* / Q000523:psychology; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000706:statistics & numerical data*; D010364:Pattern Recognition, Visual; D011594:Psychometrics / Q000706:statistics & numerical data; D011597:Psychomotor Performance; D012016:Reference Values; D015203:Reproducibility of Results; D012153:Retention, Psychology