Improving Usual Care Outcomes in Major Depression in Youth by Targeting Memory Specificity: A Randomized Controlled Trial of Adjunct Computerised Memory Specificity Training (c-MeST)

Objective: Memory Specificity Training (MeST) improves the recall of past personal experiences, an impairment in Major Depressive Disorder (MDD). Extending on previous findings that computerised MeST (c-MeST) improves memory specificity and depressive symptoms in adults, this study aimed to answer two questions: 1) does c-MeST improve memory specificity and depressive symptoms in youth with MDD; and 2) does c-MeST improve memory specificity and depression in addition to other treatment? Methods: Participants aged 15-25 (N=359, 76.5% female; M age=19.2, SD=3.1), receiving predominantly psychological therapy or counselling (85%) and/or antidepressants (52.9%) were randomised to c-MeST or wait-list. Cognitive and clinical outcomes were assessed at baseline and at one, three, and six-month follow-ups. Results: The c-MeST group reported higher memory specificity at one-month (M change=1.13, 95%CI [0.16,2.10], d=.42, p=.022), but not other follow-ups. There was no significant group difference for Major Depressive Episode diagnosis at six-months (55.6% c-MeST vs. 68.8% control, odds ratio=0.56 95%CI [0.21,1.53], p=.266), but the c-MeST group did report lower depressive symptoms at one (M change=-1.84, 95%CI[-3.42,-0.25], d = .42, p = .023) and six-month follow-ups (M change=-3.91, 95%CI [-6.19,-1.63], d = .84, p = .001). Conclusions: c-MeST reduces symptoms in youth with MDD when provided alongside other treatments. There was some evidence that change in memory specificity drives these changes. Contrary to previous findings, specificity effects were not maintained, potentially due to the low intensity of c-MeST in this study. Further study is needed to understand more about co-occurring mechanisms that produce antidepressant effects.