Promoting farsighted decisions via episodic future thinking: A meta-analysis

Episodic future thinking (EFT) denotes our capacity to imagine prospective events. It has been suggested to promote farsighted decisions that entail a trade-off between short-term versus long-term gains. Here, we meta-analyze the evidence for the impact of EFT on such intertemporal choices that have monetary or health-relevant consequences. Across 174 effect sizes from 48 articles, a three-level model yielded a medium-sized effect of g = .44, 95% (CI) [.33, .55]. Notably, this analysis included a substantial number of unpublished experiments, and the effect remained significant following further adjustments for remaining publication bias. We exploited the observed heterogeneity to determine critical core components that moderate the impact of EFT. Specifically, the effect was stronger when the imagined events were positive, more vivid, and related to the delayed choice. We further obtained evidence for the contribution of the episodicity and future-orientedness of EFT. These results indicate that the impact of EFT cannot simply be accounted for by other modes of prospection (e.g., semantic future thinking). Of note, EFT had a greater impact in samples characterized by choice impulsivity (e.g., in obesity), suggesting that EFT can ameliorate maladaptive decision making. It may accordingly constitute a beneficial intervention for individuals who tend to make myopic decisions. Our analyses moreover indicated that the effect is unlikely to merely reflect demand characteristics. This meta-analysis highlights the potential of EFT in promoting long-term goals, a finding that extends from the laboratory to real-life decisions

Memory suppression and its deficiency in psychological disorders: A focused meta-analysis

It is still debated whether suppressing the retrieval of unwanted memories causes forgetting and whether this constitutes a beneficial mechanism. To shed light on these 2 questions, we scrutinize the evidence for such suppression-induced forgetting (SIF) and examine whether it is deficient in psychological disorders characterized by intrusive thoughts. Specifically, we performed a focused meta-analysis of studies that have used the think/no-think procedure to test SIF in individuals either affected by psychological disorders or exhibiting high scores on related traits. Overall, across 96 effects from 25 studies, we found that avoiding retrieval leads to significant forgetting in healthy individuals, with a small to moderate effect size (0.28, 95% CI [0.14, 0.43]). Importantly, this effect was indeed larger than for more anxious (-0.21, 95% CI [-0.41, -0.02]) or depressed individuals (0.05, 95% CI [-0.19, 0.29])-though estimates for the healthy may be inflated by publication bias. In contrast, individuals with a stronger repressive coping style showed greater SIF (0.42, 95% CI [0.32, 0.52]). Furthermore, moderator analyses revealed that SIF varied with the exact suppression mechanism that participants were instructed to engage. For healthy individuals, the effect sizes were considerably larger when instructions induced specific mechanisms of direct retrieval suppression or thought substitution than when they were unspecific. These results suggest that intact suppression-induced forgetting is a hallmark of psychological well-being, and that inducing more specific suppression mechanisms fosters voluntary forgetting

The right prefrontal cortex supports suppression of competing memories: An investigation with transcranial direct current stimulation

Across two experiments, we sought to investigate the necessity of the right Prefrontal Cortex in successful control over interfering memories during se-lective retrieval, as indexed by the retrieval-induced forgetting effect (RIF), and the relationship between this ability and efficient motor stopping. To this end, we recruited 53 (experiment 1) and 72 (experiment 2) healthy volun-teers, which were randomly assigned to three groups that received either an-odal, cathodal, or sham trascranial Direct Current Stimulation (tDCS) to the right Inferior Frontal Gyrus while performing a standard retrieval-practice paradigm with category-exemplars word pairs, which is typically employed to induce RIF. In experiment 2 participants also performed a stop-signal task (SST) during tDCS. We analyzed memory performance data by fitting logis-tic mixed effects models in R, with item type, stimulation group, and the pos-sible interaction term as fixed effects, and subject and category as random intercept terms, in order to account for both subject- and item-related var-iability. In both experiments, RIF was impaired under real tDCS compared to sham tDCS, but only for a subset of the stimulus categories. In addition to that, we did not find neither effects of tDCS on motor stopping perfor-mance in the SST, nor a relationship between motor stopping and memory control abilities. Overall, our results support the notion that tDCS over the right Prefrontal Cortex can alter memory control performance as indexed by RIF. However, further studies are needed in order to clarify the factors that moderate the effects of tDCS on RIF across different stimulus categorie

Control over Interfering Memories in Eating Disorders

Introduction: Recent studies have suggested that patients suffering from either anorexia nervosa (AN) or bulimia nervosa (BN) exhibit abnormal performance in the ability to control cognitive interference in response selection. Method: Here, we assessed the status of cognitive control in episodic memory, by addressing the ability to inhibit interfering memories. To this end, we used the retrieval-practice paradigm, which allows for measuring both the beneficial and the detrimental effects of memory practice. The latter phenomenon, known as retrieval-induced forgetting (RIF), is thought to reflect an adaptive inhibitory mechanism aimed at reducing competition in memory retrieval. Twenty-seven healthy controls and 27 patients suffering from eating disorders (either AN or BN) performed a retrieval-practice paradigm and a control task addressing general reactivity, and filled a self- report questionnaire on impulsivity. Results: No differences between patients and healthy controls were observed for the beneficial effects of practice. The same pattern also emerged for RIF. However, when patients with AN and BN were analyzed separately, a clear dissociation emerged: patients with AN displayed no hint of RIF, whereas patients with BN showed an intact memory suppression performance. No group differences emerged in the control task. Conclusions: Our findings suggest a specific impairment in the ability to suppress interfering memories in patients with AN, thus extending current evidence of cognitive control deficits in AN to episodic memory