A multiverse analysis of early attempts to replicate memory suppression with the Think/No-think Task

In 2001, Anderson and Green [2001. Suppressing unwanted memories by executive control. Nature, 410(6826), 366-369] showed memory suppression using a novel Think/No-think (TNT) task. When participants attempted to prevent studied words from entering awareness, they reported fewer of those words than baseline words in subsequent cued recall (i.e., suppression effect). The TNT literature contains predominantly positive findings and few null-results. Therefore we report unpublished replications conducted in the 2000s (N = 49; N = 36). As the features of the data obtained with the TNT task call for a variety of plausible solutions, we report parallel "universes" of data-analyses (i.e., multiverse analysis) testing the suppression effect. Two published studies (Wessel et al., 2005. Dissociation and memory suppression: A comparison of high and low dissociative individuals' performance on the Think-No think Task. Personality and Individual Differences, 39(8), 1461-1470, N = 68; Wessel et al., 2010. Cognitive control and suppression of memories of an emotional film. Journal of Behavior Therapy and Experimental Psychiatry, 41(2), 83-89. https://doi.org/10.1016/j.jbtep.2009.10.005, N = 80) were reanalysed in a similar fashion. For recall probed with studied cues (Same Probes, SP), some tests (sample 3) or all (samples 2 and 4) showed statistically significant suppression effects, whereas in sample 1, only one test showed significance. Recall probed with novel cues (Independent Probes, IP) predominantly rendered non-significant results. The absence of statistically significant IP suppression effects raises problems for inhibition theory and its implication that repression is a viable mechanism of forgetting. The pre-registration, materials, data, and code are publicly available (https://osf.io/qgcy5/).</p

Chronic Stressors and Adolescents' Externalizing Problems:Genetic Moderation by Dopamine Receptor D4. The TRAILS Study

The existing literature does not provide consistent evidence that carriers of the Dopamine D4 Receptor 7-repeat allele are more sensitive to adverse environmental influences, resulting in enhanced externalizing problems, compared to noncarriers. One explanation is that the adverse influences examined in prior studies were not severe, chronic, or distressing enough to reveal individual differences in sensitivity reflected by DRD4-7R. This study examined whether the 7-repeat allele moderated the association between chronic stressors capturing multiple stressful aspects of individuals' lives and externalizing problems in adolescence. We expected that chronic stressor levels would be associated with externalizing levels only in 7-repeat carriers. Using Linear Mixed Models, we analyzed data from 1621 Dutch adolescents (52.2% boys), obtained in three measurement waves (mean age approximately 11, 13.5, and 16 years) from the TRacking Adolescents' Individual Lives Survey (TRAILS) population-based birth cohort and the parallel clinic-referred cohort. Across informants, we found that higher levels of chronic stressors were related to higher externalizing levels in 7-repeat carriers but not in noncarriers, as hypothesized. Although previous studies on the 7-repeat allele as a moderator of environmental influences on adolescents' externalizing problems have not convincingly demonstrated individual differences in sensitivity to adverse environmental influences, our findings suggest that adolescent carriers of the Dopamine D4 Receptor 7-repeat allele are more sensitive to chronic, multi-context stressors than noncarriers

The Role of Basal Cortisol in Predicting Change in Mental Health Problems Across the Transition to Middle School

Purpose: The period in which the transition to middle school occurs is marked by major changes in social context, social rules, and scholastic responsibilities. Some adolescents thrive during this period whereas others are overwhelmed and fail to cope adequately with their changing environment. We investigated basal cortisol upon waking as a predictor of change in mental health problems across the transition to middle school. By taking into account the transition experience, we extend prior findings that high basal cortisol predicts deteriorated mental health after the transition. In individuals with high awakening cortisol, we expected mental health problems to increase after negative transition experiences and to decrease after positive transition experiences, reflecting differential susceptibility. Evidence for the former but not the latter would suggest diathesis-stress. Methods: Data from 1,664 subjects were obtained from two measurement waves (mean ages, 11 and 13.5 years) of the TRacking Adolescents' Individual Lives Survey. Using linear regression, we investigated effects of awakening cortisol level, school transition experience, and their hypothesized interaction on change in mental health problems. Results: We found that a negative but not a positive experience was predictive of change in mental health. Importantly, our results showed that a negative experience predicts deteriorated mental health only in adolescents with high awakening cortisol but not in adolescents with low awakening cortisol. This finding was robust across informants. The converse, high awakening cortisol predicting decreasing mental health problems after a positive transition was not found. Conclusions: These results support the diathesis-stress model but not the differential susceptibility hypothesis. (c) 2015 Society for Adolescent Health and Medicine. All rights reserved

Chronic Stress and Adolescents' Mental Health:Modifying Effects of Basal Cortisol and Parental Psychiatric History. The TRAILS Study

Large individual differences in adolescent mental health following chronic psychosocial stress suggest moderating factors. We examined two established moderators, basal cortisol and parental psychiatric history, simultaneously. We hypothesized that individuals with high basal cortisol, assumed to indicate high context sensitivity, would show relatively high problem levels following chronic stress, especially in the presence of parental psychiatric history. With Linear Mixed Models, we investigated the hypotheses in 1917 Dutch adolescents (53.2 % boys), assessed at ages 11, 13.5, and 16. Low basal cortisol combined with the absence of a parental psychiatric history increased the risk of externalizing but not internalizing problems following chronic stress. Conversely, low basal cortisol combined with a substantial parental psychiatric history increased the risk of internalizing but not externalizing problems following chronic stress. Thus, parental psychiatric history moderated stress- cortisol interactions in predicting psychopathology, but in a different direction than hypothesized. We conclude that the premise that basal cortisol indicates context sensitivity may be too crude. Context sensitivity may not be a general trait but may depend on the nature of the context (e.g., type or duration of stress exposure) and on the outcome of interest (e.g., internalizing vs. externalizing problems). Although consistent across informants, our findings need replication

Collaborative recall of details of an emotional film

Collaborative inhibition refers to the phenomenon that when several people work together to produce a single memory report, they typically produce fewer items than when the unique items in the individual reports of the same number of participants are combined (i.e., nominal recall). Yet, apart from this negative effect, collaboration may be beneficial in that group members remove errors from a collaborative report. Collaborative inhibition studies on memory for emotional stimuli are scarce. Therefore, the present study examined both collaborative inhibition and collaborative error reduction in the recall of the details of emotional material in a laboratory setting. Female undergraduates (n = 111) viewed a film clip of a fatal accident and subsequently engaged in either collaborative (n = 57) or individual recall (n = 54) in groups of three. The results show that, across several detail categories, collaborating groups recalled fewer details than nominal groups. However, overall, nominal recall produced more errors than collaborative recall. The present results extend earlier findings on both collaborative inhibition and error reduction to the recall of affectively laden material. These findings may have implications for the applied fields of forensic and clinical psychology

Sensitivity to psychosocial chronic stressors and adolescents' externalizing problems:Combined moderator effects of resting heart rate and parental psychiatric history

From the literature it is not clear whether low resting heart rate (HR) reflects low or high sensitivity to the detrimental effects of adverse environments on externalizing problems. We studied parental psychiatric history (PH), reflecting general vulnerability, as possible moderator explaining these inconsistencies. Using Linear Mixed Models, we analyzed data from 1914 subjects, obtained in three measurement waves (mean age 11, 13.5, and 16 years) from the TRacking Adolescents' Individual Lives Survey population-based cohort and the parallel clinic-referred cohort. As hypothesized, more chronic stressors predicted more externalizing problems in vulnerable individuals with high resting HR but not in those with low resting HR, suggesting high vs. low sensitivity, respectively, to adverse environmental influences. Low sensitivity to adverse environmental influences in vulnerable individuals exposed to high stressor levels was additionally confirmed by high heart rate variability (Root Mean Squared Successive Difference; RMSSD). In adolescents with low vulnerability, in contrast, the association between chronic stressors and externalizing problems did not substantially differ by resting HR and RMSSD. Future research may demonstrate whether our findings extend to other adverse, or beneficial, influences. Notwithstanding their theoretical interest, the effects were small, only pertained to parent-reported externalizing problems, refer to a small subset of respondents in our sample, and are in need of replication. We conclude that HR and RMSSD are unlikely to be strong moderators of the association between stressors and externalizing problems