Emotional and non-emotional memories are suppressible under direct suppression instructions

Research on retrieval suppression has produced varying results concerning whether negatively valenced memories are more or less suppressible than neutral memories. This variability may arise if, across studies, participants adopt different approaches to memory control. Cognitive and neurobiological research points to two mechanisms that achieve retrieval suppression: thought-substitution and direct suppression (Benoit & Anderson, 2012; Bergström, de Fockert, & Richardson-Klavehn, 2009). Using the Think/No-think paradigm, this study examined whether participants can inhibit neutral and negatively valenced memories, using a uniform direct suppression strategy. Importantly, when strategy was controlled, negative and neutral items were comparably inhibited. Participants reported high compliance with direct suppression instructions, and success at controlling awareness predicted forgetting. These findings provide the first evidence that direct suppression can impair negatively valenced events, and suggest that variability in forgetting negative memories in prior studies is unlikely to arise from difficulty using direct suppression to control emotionally negative experiences

Verbal suggestions about treatment effectiveness do not modulate the effectiveness of a laboratory model of EMDR therapy:Results of two preregistered studies

Background: As for many psychotherapies, there is ongoing discussion about the role of specific versus unspecific mechanisms in the effectiveness of Eye-Movement and Desensitization Reprocessing (EMDR) therapy for post-traumatic stress disorder. However, research directly examining the potential role of non-specific mechanisms in EMDR is scarce. Objectives: Here, we address the role of one non-specific factor that is often put forward, namely treatment effectiveness expectations, in a laboratory model of EMDR therapy. Method: In a lab-based study (N = 96) and an online study (N = 173), we gave participants verbal instructions to manipulate their treatment expectations. Instructions emphasized EMDR’s effectiveness or infectiveness. Then, participants were asked to recollect an unpleasant autobiographical memory with or without making eye-movements. Results: In line with previous studies, we found significant reductions of reported vividness and emotionality of negative autobiographical memories. However, this effect was not modulated by manipulated treatment efficacy expectations. It must be noted that manipulation checks indicated that it was difficult to influence treatment effectiveness expectations using verbal suggestions. Conclusions: These findings corroborate the results of two earlier reports, suggesting that the role of treatment expectations in EMDR therapy may be limited

Lateral Eye Movements Do Not Increase False-Memory Rates: A Failed Direct-Replication Study

In this direct replication of Houben, Otgaar, Roelofs, and Merckelbach (Clinical Psychological Science, 6, 610–616, 2018), we tested whether making eye movements during memory recall increases susceptibility to creating false memories. Undergraduates (N = 206) watched a video of a car crash, after which they recalled the video with or without simultaneously making eye movements. Next, participants received misinformation about the video. Finally, during the critical test, they were questioned about video details. The results showed that making eye movements did not increase endorsement of misinformation (i.e., false memory), nor did it reduce (correct) memory details or memory vividness and emotionality. Random variation in sampling or measurement, low reliability of the test instrument, and observer-expectancy effects may explain discrepancies between study effects. Only multiple direct replications by different (independent) laboratories with standardized instruments will allow for assessing whether the effect is robust and largely independent of random variation and moderators

On EMDR: Measuring the working memory taxation of various types of eye (non-)movement conditions

Background and objective: A recent, large randomized controlled trial employing different forms of eye (non-)movements in eye movement desensitization and reprocessing (EMDR) showed that fixating the eyes either on a therapist's moving or non-moving hand led to equal reductions in symptoms of post-traumatic stress disorder (PTSD). However, numerous EMDR lab analogue studies found that eye movements produce larger memory effects than eyes stationary. These beneficial effects are typically explained by differences in working memory (WM) taxation. We tested the degree of WM taxation of several eye (non-)movement conditions used in the clinical trial. Methods: All participants (N = 40) performed: (1) eyes moving by following the experimenter's moving finger, (2) eyes fixed on the experimenter's stationary finger, (3) eyes closed, or (4) looking unfocused into the room. Simultaneously they performed a simple reaction time task. Reaction times are an objective index of the extent to which different dual attention tasks tax WM. Results: Eyes moving is more taxing than eyes fixed, while eyes fixed did not differ from eyes unfocused. All conditions were more taxing than eyes closed. Limitations: We studied WM taxation in a laboratory setting; no clinical interventions were applied. Conclusions: In line with previous lab studies, making eye movements was more taxing than eyes fixed. We discuss why this effect was not observed for reductions in PTSD symptoms in the clinical trial (e.g., differences in dependent variables, sample population, and intervention duration). For more comprehensive future insights, we recommend integration of mechanistically focused lab analogue studies and patient-oriented clinical studies

Speed Matters: Relationship between Speed of Eye Movements and Modification of Aversive Autobiographical Memories

Eye movement desensitization and reprocessing (EMDR) is an efficacious treatment for post-traumatic stress disorder. In EMDR, patients recall a distressing memory and simultaneously make eye movements (EM). Both tasks are considered to require limited working memory (WM) resources. Because this leaves fewer resources available for memory retrieval, the memory should become less vivid and less emotional during future recall. In EMDR analogue studies, a standardized procedure has been used, in which participants receive the same dual task manipulation of 1 EM cycle per second (1 Hz). From a WM perspective, the WM taxation of the dual task might be titrated to the WM taxation of the memory image. We hypothesized that highly vivid images are more affected by high WM taxation and less vivid images are more affected by low WM taxation. In study 1, 34 participants performed a reaction time task, and rated image vividness, and difficulty of retrieving an image, during five speeds of EM and no EM. Both a high WM taxing frequency (fast EM; 1.2 Hz) and a low WM taxing frequency (slow EM; 0.8 Hz) were selected. In study 2, 72 participants recalled three highly vivid aversive autobiographical memory images (n = 36) or three less vivid images (n = 36) under each of three conditions: recall + fast EM, recall + slow EM, or recall only. Multi-level modeling revealed a consistent pattern for all outcome measures: recall + fast EM led to less emotional, less vivid and more difficult to retrieve images than recall + slow EM and recall only, and the effects of recall + slow EM felt consistently in between the effects of recall + fast EM and recall only, but only differed significantly from recall + fast EM. Crucially, image vividness did not interact with condition on the decrease of emotionality over time, which was inconsistent with the prediction. Implications for understanding the mechanisms of action in memory modification and directions for future research are discussed

Norms of valence, arousal, dominance, and age of acquisition for 4300 Dutch words

This article presents norms of valence/pleasantness, activity/arousal, power/dominance, and age of acquisition for 4,300 Dutch words, mainly nouns, adjectives, adverbs, and verbs. The norms are based on ratings with a 7-point Likert scale by independent groups of students from two Belgian (Ghent and Leuven) and two Dutch (Rotterdam and Leiden-Amsterdam) samples. For each variable, we obtained high split-half reliabilities within each sample and high correlations between samples. In addition, the valence ratings of a previous, more limited study (Hermans & De Houwer, Psychologica Belgica, 34:115-139, 1994) correlated highly with those of the present study. Therefore, the new norms are a valuable source of information for affective research in the Dutch language

Norms of valence, arousal, dominance, and age of acquisition for 4,300 Dutch words

Abstract This article presents norms of valence/pleasantness, activity/arousal, power/dominance, and age of acquisition for 4,300 Dutch words, mainly nouns, adjectives, adverbs, and verbs. The norms are based on ratings with a 7-point Likert scale by independent groups of students from two Belgian (Ghent and Leuven) and two Dutch (Rotterdam and Leiden-Amsterdam) samples. For each variable, we obtained high split-half reliabilities within each sample and high correlations between samples. In addition, the valence ratings of a previous, more limited study (Hermans & De Houwer, Psychologica Belgica, 34:115-139, 1994) correlated highly with those of the present study. Therefore, the new norms are a valuable source of information for affective research in the Dutch language

Addressing climate change with behavioral science: a global intervention tournament in 63 countries

Effectively reducing climate change requires marked, global behavior change. However, it is unclear which strategies are most likely to motivate people to change their climate beliefs and behaviors. Here, we tested 11 expert-crowdsourced interventions on four climate mitigation outcomes: beliefs, policy support, information sharing intention, and an effortful tree-planting behavioral task. Across 59,440 participants from 63 countries, the interventions’ effectiveness was small, largely limited to nonclimate skeptics, and differed across outcomes: Beliefs were strengthened mostly by decreasing psychological distance (by 2.3%), policy support by writing a letter to a future-generation member (2.6%), information sharing by negative emotion induction (12.1%), and no intervention increased the more effortful behavior—several interventions even reduced tree planting. Last, the effects of each intervention differed depending on people’s initial climate beliefs. These findings suggest that the impact of behavioral climate interventions varies across audiences and target behaviors