The Netherlands Organisation for Health Research and Development.

No abstract

Objective: This meta-analysis aims to evaluate the effects of different types of physical exercise (PE) on negative symptoms in schizophrenia patients. Mind-body exercise (MBE), aerobic exercise (AE) and resistance training (RT) will be investigated. Method: The Cochrane Library, Medline, Embase and PsycINFO were searched from their inception until April 26, 2018. Randomized controlled trials comparing PE with any control group in patients with schizophrenia were included when negative symptoms had been assessed. This meta-analysis was conducted according to the PRISMA guidelines. The methodological quality of these studies was assessed with the Cochrane Risk of Bias assessment tool. Moderator, sensitivity, and meta regression analyses were conducted to explore causes of heterogeneity and impact of study quality. Results: We included 22 studies (N=1249). The overall methodological quality was poor. The meta-analysis (random effects model) showed a medium significant effect in favor of any PE intervention (Hedges' g=0.434, 95% CI=0.196 to 0.671) versus any control condition. MBE and AE respectively showed a medium significant effect (Hedges' g=0.461) and a small significant effect (Hedges' g=0.341) versus any control condition. The effect of RT could not be examined. The overall heterogeneity was high (I 2 =76%) and could not be reduced with moderator or sensitivity analyses. 3 Conclusion: This meta-analysis demonstrated that PE could be a promising intervention in the treatment of negative symptoms. However, the quality of the included studies was low and heterogeneity was high, which makes it impossible to make a clear recommendation. Therefore, results should be interpreted with care.

BackgroundImagery rescripting (ImRs) is a process by which aversive autobiographical memories are rendered less unpleasant or emotional. ImRs is thought only to be effective if a change in the meaning-relevant (semantic) content of the mental image is produced, according to a cognitive hypothesis of ImRs. We propose an additional hypothesis: that ImRs can also be effective by the manipulation of perceptual features of the memory, without explicitly targeting meaning-relevant content.MethodsIn two experiments using a within-subjects design (both N = 48, community samples), both Conceptual-ImRs—focusing on changing meaning-relevant content—and Perceptual-ImRs—focusing on changing perceptual features—were compared to Recall-only of aversive autobiographical image-based memories. An active control condition, Recall + Attentional Breathing (Recall+AB) was added in the first experiment. In the second experiment, a Positive-ImRs condition was added—changing the aversive image into a positive image that was unrelated to the aversive autobiographical memory. Effects on the aversive memory’s unpleasantness, vividness and emotionality were investigated.ResultsIn Experiment 1, compared to Recall-only, both Conceptual-ImRs and Perceptual-ImRs led to greater decreases in unpleasantness, and Perceptual-ImRs led to greater decreases in emotionality of memories. In Experiment 2, the effects on unpleasantness were not replicated, and both Conceptual-ImRs and Perceptual-ImRs led to greater decreases in emotionality, compared to Recall-only, as did Positive-ImRs. There were no effects on vividness, and the ImRs conditions did not differ significantly from Recall+AB.ConclusionsResults suggest that, in addition to traditional forms of ImRs, targeting the meaning-relevant content of an image during ImRs, relatively simple techniques focusing on perceptual aspects or positive imagery might also yield benefits. Findings require replication and extension to clinical samples.

IntroductionRuminative (abstract verbal) processing during recall of aversive autobiographical memories may serve to dampen their short-term affective impact. Experimental studies indeed demonstrate that verbal processing of non-autobiographical material and positive autobiographical memories evokes weaker affective responses than imagery-based processing. In the current study, we hypothesized that abstract verbal or concrete verbal processing of an aversive autobiographical memory would result in weaker affective responses than imagery-based processing.MethodsThe affective impact of abstract verbal versus concrete verbal versus imagery-based processing during recall of an aversive autobiographical memory was investigated in a non-clinical sample (n = 99) using both an observational and an experimental design. Observationally, it was examined whether spontaneous use of processing modes (both state and trait measures) was associated with impact of aversive autobiographical memory recall on negative and positive affect. Experimentally, the causal relation between processing modes and affective impact was investigated by manipulating the processing mode during retrieval of the same aversive autobiographical memory.ResultsMain findings were that higher levels of trait (but not state) measures of both ruminative and imagery-based processing and depressive symptomatology were positively correlated with higher levels of negative affective impact in the observational part of the study. In the experimental part, no main effect of processing modes on affective impact of autobiographical memories was found. However, a significant moderating effect of depressive symptomatology was found. Only for individuals with low levels of depressive symptomatology, concrete verbal (but not abstract verbal) processing of the aversive autobiographical memory did result in weaker affective responses, compared to imagery-based processing.DiscussionThese results cast doubt on the hypothesis that ruminative processing of aversive autobiographical memories serves to avoid the negative emotions evoked by such memories. Furthermore, findings suggest that depressive symptomatology is associated with the spontaneous use and the affective impact of processing modes during recall of aversive autobiographical memories. Clinical studies are needed that examine the role of processing modes during aversive autobiographical memory recall in depression, including the potential effectiveness of targeting processing modes in therapy.