Alan Scoboria

Initial Severity and Antidepressant Benefits: A Meta-Analysis of Data Submitted to the Food and Drug Administration

Background Meta-analyses of antidepressant medications have reported only modest benefits over placebo treatment, and when unpublished trial data are included, the benefit falls below accepted criteria for clinical significance. Yet, the efficacy of the antidepressants may also depend on the severity of initial depression scores. The purpose of this analysis is to establish the relation of baseline severity and antidepressant efficacy using a relevant dataset of published and unpublished clinical trials. Methods and Findings We obtained data on all clinical trials submitted to the US Food and Drug Administration (FDA) for the licensing of the four new-generation antidepressants for which full datasets were available. We then used meta-analytic techniques to assess linear and quadratic effects of initial severity on improvement scores for drug and placebo groups and on drug–placebo difference scores. Drug–placebo differences increased as a function of initial severity, rising from virtually no difference at moderate levels of initial depression to a relatively small difference for patients with very severe depression, reaching conventional criteria for clinical significance only for patients at the upper end of the very severely depressed category. Meta-regression analyses indicated that the relation of baseline severity and improvement was curvilinear in drug groups and showed a strong, negative linear component in placebo groups. Conclusions Drug–placebo differences in antidepressant efficacy increase as a function of baseline severity, but are relatively small even for severely depressed patients. The relationship between initial severity and antidepressant efficacy is attributable to decreased responsiveness to placebo among very severely depressed patients, rather than to increased responsiveness to medication.

Experimentally evoking nonbelieved memories for childhood events

We report on the 1st experimental elicitation of nonbelieved memories for childhood events in adults (Study 1) and children (Study 2) using a modified false memory implantation paradigm. Participants received true (trip to a theme park) and false (hot air balloon ride) narratives and recalled these events during 2 interviews. After debriefing, 13% of adults and 15% of children reported nonbelieved memories. While phenomenal ratings were higher for true than for nonbelieved memories immediately after the debriefing, after a month nonbelieved memories behaved as true memories. Also following debriefing, 23% of adults and 15% of children retracted their false memory claims. Prior to debriefing, participants with nonbelieved memories were most likely to indicate remembering the event, whereas participants with false memories who retracted their claim were most likely to endorse believing but not remembering the event. This research suggests that debriefings in previous false memory studies can lead to the development of nonbelieved memories. Additional findings regarding the correspondence between subjective belief, subjective memory, and objective memory judgments prior to and following debriefing are discussed.

Immediate and persisting effects of misleading questions and hypnosis on memory reports.

Immediate and persisting effects of misleading questions and hypnosis on memory reports were assessed. After listening to a story, 52 highly suggestible students and 59 low and medium suggestible students were asked misleading or neutral questions in or out of hypnosis. All participants were then asked neutral questions without hypnosis. Both hypnosis and misleading questions significantly increased memory errors, and misleading questions produced significantly more errors than did hypnosis. The 2 effects were additive, so that misleading questions in hypnosis produced the greatest number of errors. There were no significant interactions with level of hypnotic suggestibility. Implications of these findings for the per se exclusion of posthypnotic testimony are discussed.

The Role of Belief in Occurrence Within Autobiographical Memory

This article examines the idea that believing that events occurred in the past is a non-memorial decision that reflects underlying processes that are distinct from recollecting events. Research on autobiographical memory has often focused on events that are both believed to have occurred and remembered, thus tending to overlook the distinction between autobiographical belief and recollection. Studying event representations such as false memories, believed-not-remembered events, and non-believed memories shows the influence of non-memorial processes on evaluations of occurrence. Believing that an event occurred and recollecting an event may be more strongly dissociated than previously stated. The relative independence of these constructs was examined in 2 studies. In Study 1, multiple events were cued, and then each was rated on autobiographical belief, recollection, and other memory characteristics. In Study 2, participants described a nonbelieved memory, a believed memory, and a believed-not-remembered event, and they made similar ratings. In both studies, structural equation modeling techniques revealed distinct belief and recollection latent variables. Modeling the predictors of these factors revealed a double dissociation: Perceptual, re-experiencing, and emotional features predicted recollection and not belief, whereas event plausibility strongly predicted belief and weakly predicted recollection. The results show that judgments of autobiographical belief and recollection are distinct, that each is influenced by different sources of information and processes, and that the strength of their relationship varies depending on the type of event under study. The concept of autobiographical belief is elaborated, and implications of the findings are discussed in relation to decision making about events, social influence on memory, metacognition, and recognition processes.

Firefighter preferences regarding post-incident intervention

Abstract The effectiveness of Critical Incident Stress Debriefing (CISD) as a tool remains, at best, inconclusive. Yet in many locales CISD is mandatory for emergency services workers, including firefighters. To our knowledge, to date no study has investigated firefighters’ preferences for psychological intervention following traumatic events. To examine this, a survey was conducted with 142 members (54%) of an urban fire and rescue service in south-western Ontario, Canada. Firefighters were provided with five scenarios of varying traumatic intensity, for which they rated desirability of four voluntary post-incident interventions: CISD, individual debriefing, informal discussion, and no intervention. Firefighters expressed interest in working with post-event reactions within their peer group for all events, and an increasing interest in formal intervention as event severity increased. Individual debriefing was preferred to CISD in scenarios of low to moderate intensity. For scenarios of high intensity, ratings for all interventions were high. Expected relationships with prior CISD experience and years of service were not upheld. The essential role of informal peer-support, and the desire for meaningful intervention in severe situations, are discussed.

You and Your Best Friend Suzy Put Slime in Ms. Smollett's Desk: Producing False Memories with Self-Relevant Details

Rates of false memory reports vary markedly in the published literature. In an effort to explain these differences, the present study investigated the effects of including different types of details in a false narrative upon subsequent false memory formation. Participants were assigned to one of four conditions in which the inclusion of self-relevant and/or specific details in a false event (putting a toy in a teacher’s desk) was manipulated. Participants engaged in a standard memory recovery procedure over three interviews, involving recall for three true and one false event. Upon completion, 68.2% of participants in self-relevant groups were judged as having created memories or images about the false event, as compared with 36.4% in non-self-relevant groups. Subjective ratings of memory intensity were higher for self-relevant groups, and self-relevant participants were less likely to correctly guess the false event. These findings indicate that including self-relevant details in suggested childhood events increases the likelihood that such events will be accepted as false memories.

Script knowledge enhances the development of children’s false memories

We examined whether script knowledge contributes to the development of childrens false memories. Sixty 7-year-old and 60 11-year-old children listened to false narratives describing either a high-knowledge event (i.e., fingers being caught in a mousetrap) or a low-knowledge event (i.e., receiving a rectal enema) that were similar in terms of plausibility and pleasantness. Moreover, half of the children in each condition received additional suggestive details about the false events. Across two interviews, children had to report everything they remembered about the events. Script knowledge affected childrens false memories in that both younger and older children developed more false memories for the high-knowledge event than for the low-knowledge event. Moreover, at the first interview, additional suggestive details inhibited the development of childrens images into false memories.

Suggesting childhood food illness results in reduced eating behavior

Previous studies have shown that suggesting childhood events can influence current self-reported attitudes towards future behavior. This study shows that suggesting a false past event (i.e. becoming sick on a specific food during childhood) can modify present behavior (i.e. reduce eating of the food). Participants screened to be normal eaters received or did not receive a suggestion that they likely became sick on spoiled peach yogurt as a child. One week later they took part in an allegedly separate marketing taste-test study, during which they rated preferences for a variety of crackers and yogurts. After completing ratings, participants were invited to freely eat the remaining food while completing questionnaires. Results revealed that the participants receiving the suggestion expressed lower preference specifically for peach yogurt, and ate less yogurt of all the types, while not differing in eating of crackers. These results demonstrate that suggesting false past events influences subsequent behavior.

On the Existence and Implications of Nonbelieved Memories

In this article, we review the state of knowledge about a previously-assumed-to-be-rare memory phenomenon called nonbelieved memories. Nonbelieved memories are a counterintuitive phenomenon in which vivid autobiographical memories are no longer believed to have happened even though vivid recollective features remain present. Such memories stand in contrast to the more typical situation that when events are recollected they are also believed to have genuinely occurred. We review data on the frequency, characteristics, and factors that contribute to the development of naturally occurring and laboratory-induced nonbelieved memories and discuss the relationships of nonbelieved memories with theories of autobiographical remembering and the study of remembering in applied domains.

So that's why I don't remember: Normalising forgetting of childhood events influences false autobiographical beliefs but not memories

We investigated changes in autobiographical belief and memory ratings for childhood events, after informing individuals that forgetting childhood events is common. Participants received false prevalence information (indicating that a particular childhood event occurred frequently in the population) plus a rationale normalising the forgetting of childhood events; false prevalence information alone; or no manipulation, for one (Study 1) or two (Study 2) unlikely childhood events. Results demonstrated that combining prevalence information and the “forgetting rationale” substantially influenced autobiographical belief ratings, whereas prevalence information alone had no impact (Study 1) or a significantly lesser impact (Study 2) on belief ratings. Prevalence information consistently impacted plausibility ratings. No changes in memory ratings were observed. These results provide further support for a nested relationship between judgements of plausibility, belief, and memory in evaluating the occurrence of autobiographical events. Furthermore, the results suggest that some purported false memory phenomena may instead reflect the development of autobiographical false beliefs in the absence of memory.