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BACKGROUND While the health risks of using ecstasy warrant intervention development, a recent meta-analysis of determinants of ecstasy use identified a number of lacunae in the literature. Specifically, no studies were included that address behaviours other than 'using ecstasy' (e.g. 'trying out ecstasy' or 'ceasing ecstasy use'). However, because meta-analyses aim to integrate study results quantitatively, the resulting rigid exclusion criteria cause many studies to be discarded on the basis of their qualitative methodology. Such qualitative studies may nonetheless provide valuable insights to guide future research. To provide an overview of these insights regarding ecstasy use, the current study summarizes and combines what is known from qualitative and exploratory quantitative literature on ecstasy use. METHODS The databases PsycINFO and MedLine were searched for publications reporting reasons for ecstasy use and related behaviour, and the results were structured and discussed per behaviour and compared over behaviours. RESULTS Two main categories of reasons were found. The first category comprised reasons to start using ecstasy, use ecstasy, use ecstasy more often, and refrain from ceasing ecstasy use. The second category comprised reasons to refrain from starting to use ecstasy, use less ecstasy, and cease using ecstasy. Reasons for related behaviours within each of these two categories appear to differ, but not as substantially as between the two categories. A large number of reasons that were not yet explored in quantitative research emerged. CONCLUSIONS The current summary and combination of exploratory studies yields useful lists of reasons for each behaviour. Before these lists can inform interventions, however, they beg quantitative verification. Also, similarity of determinant configurations of different behaviours can be assessed by addressing determinants of several behaviours in one study. Another important finding is that meta-analytical integration of the literature may overlook important findings and implications. Thus, qualitative reviews remain useful instruments in setting the research agenda.(click here to hide abstract)

Self-regulation research suggested that active self-control depends on a limited resource. Therefore the capacity for self-control is lower among people who already exercised control, a phenomenon labelled as ego depletion. This experiment examines whether priming of a persistent person exemplar may help to overcome ego depletion. Half of the participants engaged in a demanding self-control task (solving extremely difficult labyrinths) whereas the other half took part in a task that demanded little self-control (solving easy labyrinths). Then, half of the participants received a person exemplar prime related to persistence; the other half received a neutral prime. Finally, participants' persistence on a subsequent self-control task (squeezing a handgrip) was measured. The effect of a person exemplar prime on a subsequent self-control task depended on initial self-control demands. Participants who exercised high initial self-control and were then presented with a persistent exemplar prime showed assimilation. Their handgrip persistence was higher than the persistence of participants who received a neutral prime. Under conditions of low initial self-control the opposite pattern was found. A persistent person prime resulted in contrast and resulted in lower handgrip performance as compared to those who received a neutral prime. (PsycINFO Database Record (c) 2007 APA, all rights reserved) (journal abstract)(click here to hide abstract)

This PhD. thesis reports eight studies into the determinants of ecstasy use behaviours. Although all prior quantitative studies into ecstasy use determinants have examined the generic behavioural category ‘using ecstasy’, these studies may not be able to inform the development of interventions aiming to prevent ecstasy use or to promote cessation. The studies reported in this thesis indicate that the key determinants of ‘using ecstasy’ are not also the key determinants of ‘trying out ecstasy’ and ‘ceasing ecstasy use’. Furthermore, ecstasy use cessation usually seems to be prompted by life style changes (e.g. job/work, relationships, losing interest in the dance scene), rather than by fear of ecstasy’s health effects. This means that health promotion efforts would do better to adopt a harm reduction approach, rather than to focus on abstinence. The current thesis reports the studies on which these conclusions are based, and the first study into the determinants of a harm reduction strategy.(click here to hide abstract)

The present paper describes three studies that examined false confessions in the laboratory. Studies 1 ( N =56) and 2 ( N =9) relied on the by now classic computer crash paradigm introduced by Kassin and Kiechel ( Psychological Science , 7 , 125–128, 1996). Study 3 ( N =12) employed a novel paradigm in which undergraduate participants were falsely accused of exam fraud. Our data indicate that false confessions do occur, even when conditions become more ecologically valid. Furthermore, we explored whether individual differences in compliance, suggestibility, fantasy proneness, dissociation, and cognitive failures are related to false confessions. Of these, only fantasy proneness was associated with false confessions.(click here to hide abstract)