No abstract

Research has shown that negative affect reduces working memory capacity. Commonly, this effect has been attributed to an allocation of resources to task-irrelevant thoughts, suggesting that negative affect has detrimental consequences for working memory performance. However, rather than simply being a detrimental effect, the affect-induced capacity reduction may reflect a trading of capacity for precision of stored representations. To test this hypothesis, we induced neutral or negative affect and concurrently measured the number and precision of representations stored in sensory and working memory. Compared with neutral affect, negative affect reduced the capacity of both sensory and working memory. However, in both memory systems, this decrease in capacity was accompanied by an increase in precision. These findings demonstrate that observers unintentionally trade capacity for precision as a function of affective state and indicate that negative affect can be beneficial for the quality of memories.

Using DRM lists (Roediger & McDermott, 1995) in two experiments, we compared the effects of retrieval practice on a subset of the items and of the presentation of those items as retrieval cues at test on recall of the lists' critical items. In Experiment 1, the critical items were part of the studied lists, thus addressing these items' veridical recall; in Experiment 2, they were not studied, thus addressing these items' false recall. Three major results emerged. First, retrieval practice and part-list cuing reduced both veridical and false recall. Second, the two manipulations induced an integration effect in veridical recall, with substantial forgetting in lists with low false recall levels and no forgetting in lists with high false recall levels. Third, retrieval practice and part-list cuing created the same effects on recall, qualitativelyand quantitatively.These results suggest that the detrimental effects of retrieval practice and part-list cuing were mediated by similar mechanisms. They are consistent with the view that not only retrieval-induced forgetting, but also part-list cuing is caused by inhibitory processes.

Repeated retrieval of a subset of previously observed events can cause forgetting of the non-retrieved events. We examined how affective states experienced during retrieval modulate such retrieval-induced forgetting by inducing positive, negative, and neutral moods in subjects immediately before they attempted to retrieve studied items. On the basis of recent work, we hypothesized that positive moods encourage relational processing, which should increase interference from related events and thus enhance retrieval-induced forgetting. By contrast, negative moods should encourage item-specific processing, which should reduce interference and thus reduce such forgetting. Our results are consistent with these predictions. When subjects were in negative moods, repeated retrieval did not cause forgetting of the non-retrieved material, whereas when subjects were in positive and neutral moods, they showed reliable retrieval-induced forgetting. Our findings suggest that the emotions involved during interrogation of a witness can affect the result of repeated interrogations.

BackgroundBased on introspectionist, semantic, and psychophysiological experimental frameworks, it has long been assumed that all affective states derive from two independent basic dimensions, valence and arousal. However, until now, no study has investigated whether valence and arousal are also dissociable at the level of affect-related changes in cognitive processing.Methodology/Principal FindingsWe examined how changes in both valence (negative vs. positive) and arousal (low vs. high) influence performance in tasks requiring executive control because recent research indicates that two dissociable cognitive components are involved in the regulation of task performance: amount of current control (i.e., strength of filtering goal-irrelevant signals) and control adaptation (i.e., strength of maintaining current goals over time). Using a visual pop-out distractor task, we found that control is exclusively modulated by arousal because interference by goal-irrelevant signals was largest in high arousal states, independently of valence. By contrast, control adaptation is exclusively modulated by valence because the increase in control after trials in which goal-irrelevant signals were present was largest in negative states, independent of arousal. A Monte Carlo simulation revealed that differential effects of two experimental factors on control and control adaptation can be dissociated if there is no correlation between empirical interference and conflict-driven modulation of interference, which was the case in the present data. Consequently, the observed effects of valence and arousal on adaptive executive control are indeed dissociable.Conclusions/SignificanceThese findings indicate that affective influences on cognitive processes can be driven by independent effects of variations in valence and arousal, which may resolve several heterogeneous findings observed in previous studies on affect-cognition interactions.