Heightened familiarity drives the negative retrieval bias in depression: Evidence from the PRISM task.

Major Depressive Disorder (MDD) is associated with emotional memory deficits, but treatment is limited by a poor understanding of the mechanisms that drive such behavior. Our previous work linked depression to a negative retrieval bias rooted in abnormal evidence accumulation (Cataldo et al., 2023). The Drift Diffusion Model can account for this bias in two ways: increased familiarity, in which depression strengthens evidence for all negative memories-even false ones; or motivated retrieval, in which depression increases the propensity to judge negative items as "old"-even if they are weak. Thus, it is unclear whether depression affects the quality of negative memories or the way they are acted upon. The current work distinguishes these accounts via the Parceling Recognition Into Strength and Motivation (PRISM) task, which isolates memory from decision processes by extending single-item recognition to forced choices between targets and lures (Starns et al., 2018). Though motivation to respond "old" can bias single-item judgments, it should play little or no role when judging which item is old; thus, familiarity is implicated when valence effects extend across both tasks, and motivation is implicated when they do not. In a sample of 53 adults ranging in depressive severity, we found that the negative retrieval bias extended across single-item and forced-choice recognition, thus supporting false familiarity. A qualitative analysis of participants' self-reported strategies further indicated that increased schema use may be an important mechanism. In sum, we provide critical evidence that the negative retrieval bias in depressed adults results from disrupted memory representations.