Early life stress explains reduced positive memory biases in remitted depression

Abstract

BackgroundThere is contradictory evidence regarding negative memory biases in major depressive disorder (MDD) and whether these persist into remission, which would suggest their role as vulnerability traits rather than correlates of mood state. Early life stress (ELS), common in patients with psychiatric disorders, has independently been associated with memory biases, and confounds MDD versus control group comparisons. Furthermore, in most studies negative biases could have resulted from executive impairments rather than memory difficulties per se.MethodsTo investigate whether memory biases are relevant to MDD vulnerability and how they are influenced by ELS, we developed an associative recognition memory task for temporo-spatial contexts of social actions with low executive demands, which were matched across conditions (self-blame, other-blame, self-praise, other-praise). We included fifty-three medication-free remitted MDD (25 with ELS, 28 without) and 24 healthy control (HC) participants without ELS.ResultsOnly MDD patients with ELS showed a reduced bias (accuracy/speed ratio) towards memory for positive vs. negative materials when compared with MDD without ELS and with HC participants; attenuated positive biases correlated with number of past major depressive episodes, but not current symptoms. There were no biases towards self-blaming or self-praising memories.ConclusionsThis demonstrates that reduced positive biases in associative memory were specific to MDD patients with ELS rather than a general feature of MDD, and were associated with lifetime recurrence risk which may reflect a scarring effect. If replicated, our results would call for stratifying MDD patients by history of ELS when assessing and treating emotional memories.

Blame-rebalance fMRI neurofeedback in major depressive disorder: A randomised proof-of-concept trial

“…We recently provided evidence that reduced positive memory biases, as successfully targeted in previous neurofeedback studies (Young et al, 2017; 2014), were only present in a subgroup of people with MDD. It was only those patients with early life stress who had reduced positive memory biases and these were associated with number of previous episodes, suggesting their role in “scarring” which may increase future vulnerability (Gethin et al, 2017). This indicates that neurofeedback interventions targeting positive memories may be most effective in MDD patients with early life stress.…”

A Pilot Study of Smartphone-Based Memory Bias Modification and Its Effect on Memory Bias and Depressive symptoms in an Unselected Population

“…Some digitalized treatment options have been developed based on cognitive risk factors for depression. The cognitive theory of depression states that latent dysfunctional schemas and biased cognitive processing are mechanisms involved in the onset and persistence of depressive symptoms (Beck 2008;Disner et al 2011;Gethin et al 2017;LeMoult et al 2017;LeMoult and Gotlib 2018). Underlying dysfunctional schemas seem to drive biased information processing, thus filtering and over-representing internal, external or incoming information.…”

Emotional Biases and Recurrence in Major Depressive Disorder. Results of 2.5 Years Follow-Up of Drug-Free Cohort Vulnerable for Recurrence

“…In addition Vrijsen et al also reported increased negative memory bias for negative stimuli in remitted MDD after a sad mood induction, which was not specifically associated with having recurrent MDD (48). Interestingly, Gethin and colleagues reported that reductions in positivity bias in a comparable sample of remitted MDD-patients were only found in subjects reporting early life stress (47). In post-hoc analyses, approximating the analyses by Gethin et al we did not find evidence for an effect of early life stress [assessed by the CTQ (71, 72)] on reductions of recall of positive (relative to negative) words in our sample (results available on request).…”