Koen Vanbrabant

Greater positive affect change after mental imagery than verbal thinking in a student sample.

This study sought to replicate previous work concerning the impact of positive mental imagery on emotion. Previous experimental studies found that imagining positive events was superior to verbally processing the same events in producing positive affect, and further that field rather than observer perspective imagery had a more powerful impact (Holmes, Coughtrey, & Connor, 2008; Holmes, Mathews, Dalgleish, & Mackintosh, 2006). In the current study, 78 students listened to 100 positive events randomly allocated to one of three conditions (between-subjects): imagining them via a field or an observer perspective or listening to the same events while thinking about their verbal meaning. Positive affect was measured before and after the task. Positive affect change was greater after imagery (field and observer) than the verbal condition, replicating previous research. Contrary to predictions, there was no significant difference in affect change between the field and observer conditions. To explain the latter result, we reflect on methodological explanations. In conclusion, there was greater positive affect change after positive mental imagery than positive verbal thinking. If results can be translated from the lab to the clinic then imaging positive situations may help people feel more positive than only discussing them verbally in therapy.

Abstract Thinking about Negative Events in Dysphoric Students Leads to Negative Generalization

The severity of many psychological disorders is associated with an increasing amount of different stimuli or situations that elicit a maladaptive response. This is known as the process of (over)-generalization and is often characteristic of individuals with emotional disorders. Recently, abstract repetitive thought has been proposed to be a transdiagnostic marker in several disorders (e.g., worry in anxiety; rumination in depression). The present study examined the impact of an abstract thinking style (compared to a more concrete thinking style) as a mechanism that contributes to generalization. Students (N = 83) were trained in either an abstract or concrete thinking mode and then completed a learning phase and finally a generalization test phase. High dysphoric students showed more negative generalization in the abstract condition compared to the concrete condition. For low dysphoric participants, the two thinking styles did not result in a difference in generalization. Implications for the transdiagnostic value of an abstract processing style in depression and anxiety are discussed.

A new approach for modeling generalization gradients: A case for hierarchical models

A case is made for the use of hierarchical models in the analysis of generalization gradients. Hierarchical models overcome several restrictions that are imposed by repeated measures analysis-of-variance (rANOVA), the default statistical method in current generalization research. More specifically, hierarchical models allow to include continuous independent variables and overcomes problematic assumptions such as sphericity. We focus on how generalization research can benefit from this added flexibility. In a simulation study we demonstrate the dominance of hierarchical models over rANOVA. In addition, we show the lack of efficiency of the Mauchlys sphericity test in sample sizes typical for generalization research, and confirm how violations of sphericity increase the probability of type I errors. A worked example of a hierarchical model is provided, with a specific emphasis on the interpretation of parameters relevant for generalization research.

Accuracy and usability of the eGVHD app in assessing the severity of graft-versus-host disease at the 2017 EBMT annual congress

Graft-versus-host disease (GvHD) is one of the most significant complications of allogeneic stem cell transplantation. Several international guidelines streamline its diagnosis and severity scoring [1–4,12]. Their implementation, however, remains challenging due to the variety of presentations of GvHD and the absence of validated biomarkers to confirm diagnosis. Poor GvHD assessment can be also due to sub-optimal knowledge of guidelines, incomplete patient assessment and/or lack of experience, as repeatedly shown through surveys [5–9] and expert board reviews of clinical trials data [10, 11]. Improving the accuracy of GvHD assessment has thus the potential to enhance the validity of research findings and clinical observations. E-tools can improve data capturing bedside, by offering easy and intuitive access to the latest guidelines, as well as automated help in applying complex decision algorithms. The Complications and Quality of Life Transplant Complications Working Party (CQLWP) of the European Society for Blood and Marrow Transplantation (EBMT) has therefore developed the eGVHD App to serve as a ‘pocketGvHD expert’ and its preliminary testing in a limited number of healthcare professionals was promising [7]. Here we aimed at further testing the accuracy and usability of the eGVHD App in a more diverse group of healthcare professionals and to evaluate current practice patterns in GvHD assessment. To do so, we used a ‘prepost’ single arm design involving a convenience sample of interdisciplinary healthcare professionals participating in the CQLWP eGVHD App session during the EBMT 2017 annual congress in Marseilles, France. This 60-min session provided general information on the eGVHD App’s functionalities, followed by an interactive survey on GvHD assessment skills and practice patterns. All participants, who had access to an interactive voting system (IVS) device (TurningPoint) to record their answers and a mobile device (tablet, smartphone, and laptop) to access the App, could participate in the study.

Training discrimination diminishes maladaptive avoidance of innocuous stimuli in a fear conditioning paradigm

Anxiety disorders are the most common mental disorder worldwide. Although anxiety disorders differ in the nature of feared objects or situations, they share a common mechanism by which fear generalizes to related but innocuous objects, eliciting avoidance of objects and situations that pose no objective risk. This overgeneralization appears to be a crucial mechanism in the persistence of anxiety psychopathology. In this study we test whether an intervention that promotes discrimination learning reduces generalization of fear, in particular, harm expectancy and avoidance compared to an irrelevant (control) training. Healthy participants (N = 80) were randomly allocated to a training condition. Using a fear conditioning paradigm, participants first learned visual danger and safety signals (set 1). Baseline level of stimulus generalization was tested with ambiguous stimuli on a spectrum between the danger and safety signals. There were no differences between the training groups. Participants then received the stimulus discrimination training or a control training. After training, participants learned a new set of danger and safety signals (set 2), and the level of harm expectancy generalization and behavioural avoidance of ambiguous stimuli was tested. Although the training groups did not differ in fear generalization on a cognitive level (harm expectancy), the results showed a different pattern of avoidance of ambiguous stimuli, with the discrimination training group showing less avoidance of stimuli that resembled the safety signals. These results support the potential of interventions that promote discrimination learning in the treatment of anxiety disorders.