Mood and the False Memory Effect

The Deese-Roediger-McDermott paradigm lures people to produce false memories. Two experiments examined whether induced positive or negative moods would influence this false memory effect. The affect-as-information hypothesis predicts that, on the one hand, positive affective cues experienced as task-relevant feedback encourage relational processing during encoding, which should enhance false memory effects. On the other hand, negative affective cues are hypothesized to encourage item-specific processing at encoding, which should discourage such effects. The results of Experiment 1 are consistent with these predictions: Individuals in negative moods were significantly less likely to show false memory effects than those in positive moods or those whose mood was not manipulated. Experiment 2 introduced inclusion instructions to investigate whether moods had their effects at encoding or retrieval. The results replicated the false memory finding of Experiment 1 and provide evidence that moods influence the accessibility of lures at encoding, rather than influencing monitoring at retrieval of whether lures were actually presented. Affect can sometimes enhance and sometimes impair performance and memory (Gray, 2001; Gray, Braver, & Raichle, 2002; Packard, Cahill, & McGaugh, 1994). For instance, although extreme emotional stress can impair memory (Packard et al., 1994; see also McIntyre, Power, Roozendaal, & McGaugh, 2003), McGaugh and his colleagues (Packard et al., 1994; McIntyre et al., 2003) have shown that moderate emotional stress improves learning how to navigate a maze using place cues. Similarly, Gray (2001) found that negative moods enhanced performance on spatial tasks, but impaired performance on verbal tasks. Conversely, he found that positive moods can enhance performance on verbal tasks, but impair performance on spatial tasks. These effects for positive mood are consistent with those of Isen and her colleagues showing that positive moods enhance creativity on verbal association tasks (Isen, 1987). The goal of the research we report here was to investigate how affective states might influence false memory effects using the highly popular Deese-Roediger-McDermott (DRM) paradigm.