On the relative role of inhibition in age-related working memory decline

In this cross-sectional study, the mediating role of inhibition relative to speed in age-related working memory decline on different tasks was investigated. It was hypothesized that the role of inhibition is marginal or absent in a relatively "passive" or simple working memory task, but present in a relatively "active" or complex task in which the processing, rather than the storage capacity of working memory, is addressed. This hypothesis was tested with a structural equation model that was fitted on a subsample (N = 213) of the Maastricht Aging Study (MAAS). The first trial of the Verbal Learning Test (VLT) served as the passive test and the Self-Paced Auditory Serial Addition Task (SPASAT) as the active test. Results showed that the role of inhibition was absent in predicting VLT performance, whereas it was comparable to the role of speed in predicting SPASAT performance. These findings suggest a relative, task-dependent role of inhibition in explaining age-related memory decline.     

Embedding lies into truthful stories does not affect their quality

When given the opportunity, liars will embed their lies into otherwise truthful statements. In what way this embedding affects the quality of lies, however, remains largely unknown. This study investigated whether lies that are embedded into truthful stories are richer in detail and contain higher quality details compared to lies that are part of entirely fabricated statements. Participants (N = 111) were asked to provide a statement that was either entirely truthful, entirely fabricated, or had the fabricated element of interest embedded into an otherwise truthful story. Results indicated that lies embedded in a fabricated statement are not qualitatively different from lies embedded in an otherwise truthful statement. Supporting Bayes factors provided moderate to strong evidence for this conclusion. Accordingly, verbal credibility assessment tools based on the verbal content measured in this study may be robust against the embedding of lies.     

Stereotypical behavioural cues — but not their order — influence credibility judgements

To what extent stereotypical deceptive behaviours such as gaze aversion and fidgeting actually influence people's credibility judgements remain largely unknown. In this study, we directly manipulated the presence/absence of such behaviours to investigate this. Participants were shown four truthful videos in which we manipulated the presence of stereotypical cues and asked them to judge how credible the person in each video is. Moreover, research consistently shows that decision making is influenced by various cognitive biases. One example is the primacy effect, which implies that people form an opinion early in the decision process. Information acquired early will have the largest influence on how subsequent information will be interpreted. To investigate a possible primacy effect, we also manipulated whether these cues were present towards the beginning or the end of the video (i.e. the timing of the manipulation). In line with our expectations, the presence of stereotypical cues significantly lowered the observed credibility, showing that the presence of these cues indeed influences credibility judgements. The timing of the cues had no effect.     

The person response function as a tool in person-fit research

Item responses that do not fit an item response theory (IRT) model may cause the latent trait value to be inaccurately estimated. In the past two decades several statistics have been proposed that can be used to identify nonfitting item score patterns. These statistics all yieldscalar values. Here, the use of the person response function (PRF) for identifying nonfitting item score patterns was investigated. The PRF is afunction and can be used for diagnostic purposes. First, the PRF is defined in a class of IRT models that imply an invariant item ordering. Second, a person-fit method proposed by Trabin & Weiss (1983) is reformulated in a nonparametric IRT context assuming invariant item ordering, and statistical theory proposed by Rosenbaum (1987a) is adapted to test locally whether a PRF is nonincreasing. Third, a simulation study was conducted to compare the use of the PRF with the person-fit statistic ZU3. It is concluded that the PRF can be used as a diagnostic tool in person-fit research.The authors are grateful to Coen A. Bernaards for preparing the figures used in this article, and to Wilco H.M. Emons for checking the calculations.     

Using an Example Statement Increases Information but Does Not Increase Accuracy of CBCA,RM, and SCAN

Verbal credibility assessment methods are frequently used in the criminal justice system to investigate the truthfulness of statements. Three of these methods are Criteria Based Content Analysis (CBCA), Reality Monitoring (RM), and Scientific Content Analysis (SCAN). The aim of this study is twofold. First, we investigated the diagnostic accuracy of CBCA, RM, and especially SCAN. Second, we tested whether giving the interviewee an example of a detailed statement can enhance the diagnostic accuracy of these verbal credibility methods. To test the latter, two groups of participants were requested to write down one true and one fabricated statement about a negative event. Prior to this request, one group received a detailed example statement, whereas the other group received no additional information. Results showed that CBCA and RM scores differed between true and fabricated statements, whereas SCAN scores did not. Giving a detailed example statement did not lead to better discrimination between truth tellers and liars for any of the methods but did lead to the participants producing significantly longer statements. The implications of these findings are discussed. Copyright © 2013 John Wiley & Sons, Ltd.     

Differential Outcomes of Adolescents with Chronically Ill and Healthy Parents

Approximately 10% of children grow up with a parent who has been diagnosed with a chronic medical condition (CMC) and seem to be at risk for adjustment difficulties. We examined differences in behavioral, psychosocial and academic outcomes between 161 adolescents from 101 families with a chronically ill parent and 112 adolescents from 68 families with healthy parents, accounting for statistical dependence within siblings. Children between 10 and 20 years and their parents were visited at home and filled in questionnaires. Multilevel analyses showed that 20–60% of the variance in most adolescent outcomes was due to the family cluster effect, especially in internalizing problem behavior, caregiving variables and quality of parent attachment. Conversely, the variance in stress and coping variables and grade point average (GPA) was mainly due to individual characteristics. Adolescents with parents affected by CMC displayed more internalizing problems than the comparison group and scored higher on frequency of household chores, caregiving responsibilities, activity restrictions, isolation, daily hassles and stress. In addition, their grade point average was comparatively worse. No group differences in externalizing problems, coping skills and quality of parent attachment were found. In conclusion, the family cluster effect largely explains adolescent outcomes and should be accounted for. Adolescents with parents affected by CMC are subject to an increased risk for internalizing problems, adverse caregiving characteristics, daily hassles, stress and a low GPA. According to a family-centered approach, school counselors and health care practitioners should be alert to adjustment difficulties of children with a chronically ill parent.     

The origin of children's implanted false memories: Memory traces or compliance?

A longstanding question in false memory research is whether children's implanted false memories represent actual memory traces or merely result from compliance. The current study examined this question using a response latency based deception task. Forty-five 8-year-old children received narratives about a true (first day at school) and false event (hot air balloon ride). Across two interviews, 58/32% of the participants developed a partial/full false memory. Interestingly, these children also showed higher false recall on an unrelated DRM paradigm compared to children without a false memory. The crucial finding, however, was that the results of the deception task revealed that children with partial and full false memories were faster to confirm than to deny statements relating to the false event. This indicates that children's implanted false memories reflect actual memory traces, and are unlikely to be explained by mere compliance.