The aim of this study was to investigate whether difficulties in forgetting (like difficulties in remembering) are associated with depressive states. First, dysphoric and nondysphoric students learned 40 word pairs, each consisting of a positive or negative adjective and a neutral noun (target). Next, the students practiced responding with some targets and suppressing others, when given the adjective as cue, for a varied number of repetitions. On the final test, they were told to disregard the prior instruction to suppress and to recall the target associated with every cue. Compared with nondysphoric students, dysphoric students recalled similar percentages of targets from sets assigned for response practice but higher percentages from sets assigned for suppression practice. The degree of forgetting showed some mood-congruent tendencies and was significantly correlated with self-report measures of rumination and unwanted thoughts.
Hertel, P.T., & Gerstle, M. (2003). Depressive deficits in forgetting. Psychological Science, 14(6), 573-578. doi: 10.1046/j.0956-7976.2003.psci_1467.x