Development and psychometric evaluation of a scrambled sentences test specifically for worry in individuals with generalised anxiety disorder

The tendency to draw negative conclusions from ambiguous information (interpretation bias) is prevalent across emotional disorders and plays a key role in the development and maintenance of pathological worry and anxious mood. Assessing interpretation bias using valid and reliable measures is central to empirical research. A commonly used measure of interpretation bias is the scrambled sentences test (SST), originally relating to depression. Given the association between interpretation bias and worry, we aimed to develop and psychometrically evaluate a new version of the SST with items pertaining to common worry domains for use in worry and anxiety research. In Studies 1–3 (analogue samples, combined N = 288), the new worry SST showed excellent construct validity (moderate-to-strong associations with worry and anxiety-related measures), and reliability (split-half and test-retest reliability). We confirmed construct validity in Study 4 (N = 215 individuals with generalised anxiety disorder). Furthermore, we demonstrated version specificity in analogue and clinical samples: the worry SST was associated with trait worry but not trait rumination, while the original depression SST largely showed the opposite pattern. Overall, the new worry SST is a psychometrically robust measure that may be especiall

Modeling of light scattering and haze in semicrystalline polymers

This article reports a new model approach for the description of light scattering in semicrystalline polymers, to describe more precisely the influence of supermolecular structure on the optical properties. This is the first study in which light scattering of polymer films has been modeled using exact Mie scattering theory of radially anisotropic spheres. As a model material a well‐known polymer, isotactic polypropylene (iPP) was used. Samples were prepared with different sample thicknesses and crystalline structures in order to identify the key parameters of light scattering in polycrystalline polymeric systems. Validation haze measurements were carried out with a spectrophotometer equipped with a 150 mm snap‐in integrating sphere. It was found that the optical properties of the polycrystalline sample can be described using multiple light scattering on these scattering centers. Good agreement was found between the simulated and experimentally measured haze values which proves the reliability and applicability of our new approach

tDCS increases anxiety reactivity to intentional worry

While considerable experimental research has examined the impact of transcranial direct current stimulation (tDCS) on a range of cognitive processes associated with emotional pathology, the impact of tDCS on worry has been comparatively neglected. Given that anxiety pathology is characterised by motivated engagement in worry, and that frontal tDCS has the capacity to enhance goal-oriented cognition, it is important to examine whether tDCS would increase or ameliorate the cognitive and emotional effects of worry. In the current study we examined how tDCS influenced the anxiety response to worry, and the frequency of negative intrusive thoughts. We additionally examined whether stimulation delivered in isolation, or in combination with a mindful-focus task would augment the effects of tDCS. Ninety-seven (75 female) healthy participants received either active or sham anodal tDCS to the left dorsolateral prefrontal cortex, delivered either in isolation or concurrently with a mindful task (four conditions). The frequency of negative thoughtc intrusions was assessed before and after a period of instructed worry, and state anxiety was assessed across the study. Active tDCS was associated with significantly greater elevation in anxiety in response to the worry induction. No effects were observed on the frequency of negative thought intrusions, and the combined delivery of tDCS with the concurrent mindful task did not alter the pattern of observed effects. While inviting replication in a high anxious sample, the present results highlight the possibility that tDCS may interact with motivated engagement in negative patterns of cognition, such as worry, to produce greater emotional reactivity

Using event-related potential and behavioural evidence to understand interpretation bias in relation to worry

Worry is a common experience, thought to be maintained by the tendency of interpreting ambiguous information in a consistent (e.g. negative) manner, termed “interpretation bias”. This study explored whether high worriers (Penn State Worry Questionnaire score, PSWQ ≧ 56) and low worriers (PSWQ score ≦ 39) show different interpretation biases, and examined at which stages of information processing these interpretation biases occur. Participants with high and low worry levels completed interpretation assessment tasks yielding behavioural and event-related potential indices. We focused on the N400 component, reflecting whether given interpretations were in line with or violated participants' own interpretations. We found that high worriers lack the benign interpretation bias found in low worriers from the early "online" interpretative stage, reflected by the reaction time in a relatedness judgment task and the N400 in a lexical decision task, to the later "offline" stage at which participants had time for reflection. Our results suggest that a benign interpretation bias may be a protective factor in relation to worry and is likely to remain active across online and offline stages of interpretation processing

Using event-related potential and behavioural evidence to understand interpretation bias in relation to worry

The tendency to interpret ambiguous information in a consistent (e.g., negative) manner (interpretation bias) may maintain worry. This study explored whether high and low worriers generate different interpretations and examined at which stages of information processing these interpretations can occur. Participants completed interpretation assessment tasks yielding behavioural and N400 event-related potential indices, which index whether a given interpretation was generated. High worriers lacked the benign interpretation bias found in low worriers. This was evident for early “online” interpretations (reflected in reaction times to relatedness judgments and lexical decisions, as well as at a neurophysiological level, N400, for lexical decisions only), to later “offline” interpretations (observed at a behavioural level on the scenario task and recognition task) when participants had time for reflection. Results suggest that a benign interpretation bias may be a protective factor for low worriers, and that these interpretations remain active across online and offline stages of processing

Impact of imagery-enhanced interpretation training on offline and online interpretations in worry

Worry and rumination are forms of repetitive negative thinking (RNT) that are maintained by negative interpretations and a predominance of abstract, verbal thinking. Hence, facilitating more positive interpretations and imagery-based thinking in combination may reduce RNT. Study 1 administered interpretation training with and without enhanced imagery, and an active control condition (designed not to change interpretations), in individuals with high levels of RNT (worry and/or rumination). Combining interpretation training with sustained imagery resulted in the highest levels of positive interpretation bias using an offline test of interpretation bias (when individuals have time to reflect). Study 2 investigated whether imagery-enhanced interpretation training influences online interpretations when ambiguous information is first encountered, indexed by reaction times and amplitude of the N400 event-related potential, as well as enhances offline positive interpretations in high worriers. It also examined whether imagery-enhanced interpretation training reduces negative thought intrusions associated with worry. Both online (reaction time) and offline interpretations were more positive following imagery-enhanced interpretation training, and negative thoughts were reduced, compared to the active control. However, no differences emerged on neurophysiological markers during the online task. Hence, brief interpretation training encompassing sustained imagery modifies online and offline interpretations, but further training may be required to impact upon neurophysiological measures

Internet-Delivered Interpretation Training Reduces Worry and Anxiety in Individuals With Generalized Anxiety Disorder: A Randomized Controlled Experiment

Objective: Generalized anxiety disorder (GAD) is a debilitating condition, characterized by negative interpretations about ambiguous situations. This study tested whether entirely internet-delivered interpretation training [cognitive bias modification (CBM)] versus control promotes positive interpretations and reduces worry and anxiety in individuals with GAD, with or without depression. Method: A two-arm (CBM; control) parallel-group randomized controlled experiment. Assessments were preintervention (T0), postintervention (T1), 1-month (T2) postintervention, and 3-month (T3) postintervention. Participants with GAD (with or without comorbid depression) were randomly allocated to either CBM (n = 115) or control (n = 115). Participants, but not researchers, were blind to allocated condition. Participants completed up to 10 online CBM or control sessions across 1 month. Interpretation bias [coprimary outcomes: scrambled sentence test (SST), recognition test (RT)], and number of negative thought intrusions during a breathing focus task were measured at T0 and T1. Self-reported levels of worry [Penn State Worry Questionnaire-trait (PSWQ trait); Penn State Worry Questionnaire-past week (PSWQ weekly)], anxiety [Generalized Anxiety Disorder scale (GAD-7)], depression [Patient Health Questionnaire (PHQ-9)], rumination [Ruminative Response Scale (RRS)], and repetitive negative thinking [RNT; Repetitive Thinking Questionnaire-trait (RTQ-trait)] were assessed at T0–T3. Results: The per-protocol analyses included N = 186 participants (CBM n = 94; control n = 92). As predicted, we found moderate-to-large training effects on the primary outcome of interpretation bias at T1. Secondary outcomes of negative thought intrusions at T1 and selfreported symptoms at T2 were all significantly lower in the CBM versus control condition. All but one effect (trait RNT) were sustained at T3. Conclusions: In this randomized controlled study, we found that fully online interpretation training ameliorated core features of GAD in individuals with or without comorbid depression up to 3 months posttraining

The perseverative worry bout: a review of cognitive, affective and motivational factors that contribute to worry perseveration

This paper reviews the cognitive, affective and attentional factors that contribute to individual perseverative worry bouts. We describe how automatic biases in attentional and interpretational processes contribute to threat detection and to the inclusion of negative intrusive thoughts into the worry stream typical of the “what if …?” thinking style of pathological worriers. The review also describes processes occurring downstream from these perceptual biases that also facilitate perseveration, including cognitive biases in beliefs about the nature of the worry process, the automatic deployment of strict goal-directed responses for dealing with the threat, the role of negative mood in facilitating effortful forms of information processing (i.e. systematic information processing styles), and in providing negative information for evaluating the success of the worry bout. We also consider the clinical implications of this model for an integrated intervention programme for pathological worrying

ENIGMA-anxiety working group: rationale for and organization of large-scale neuroimaging studies of anxiety disorders

Anxiety disorders are highly prevalent and disabling but seem particularly tractable to investigation with translational neuroscience methodologies. Neuroimaging has informed our understanding of the neurobiology of anxiety disorders, but research has been limited by small sample sizes and low statistical power, as well as heterogenous imaging methodology. The ENIGMA-Anxiety Working Group has brought together researchers from around the world, in a harmonized and coordinated effort to address these challenges and generate more robust and reproducible findings. This paper elaborates on the concepts and methods informing the work of the working group to date, and describes the initial approach of the four subgroups studying generalized anxiety disorder, panic disorder, social anxiety disorder, and specific phobia. At present, the ENIGMA-Anxiety database contains information about more than 100 unique samples, from 16 countries and 59 institutes. Future directions include examining additional imaging modalities, integrating imaging and genetic data, and collaborating with other ENIGMA working groups. The ENIGMA consortium creates synergy at the intersection of global mental health and clinical neuroscience, and the ENIGMA-Anxiety Working Group extends the promise of this approach to neuroimaging research on anxiety disorders

Mega-analysis methods in ENIGMA: the experience of the generalized anxiety disorder working group

The ENIGMA group on Generalized Anxiety Disorder (ENIGMA‐Anxiety/GAD) is part of a broader effort to investigate anxiety disorders using imaging and genetic data across multiple sites worldwide. The group is actively conducting a mega‐analysis of a large number of brain structural scans. In this process, the group was confronted with many methodological challenges related to study planning and implementation, between‐country transfer of subject‐level data, quality control of a considerable amount of imaging data, and choices related to statistical methods and efficient use of resources. This report summarizes the background information and rationale for the various methodological decisions, as well as the approach taken to implement them. The goal is to document the approach and help guide other research groups working with large brain imaging data sets as they develop their own analytic pipelines for mega‐analyses