Mood-as-input theory and specific negative moods for perseverative checking and worrying

The mood-as-input hypothesis predicts that perseveration at an open-ended task is determined by “stop rules” for the task and by the valency of the mood. Stop rules define a person’s goals in task attainment, e.g. stopping after doing as much as they can, or stopping when they no longer feel like continuing. This thesis will examine the combined effects of stop rules and specific negative moods (sadness, anxiety, anger) on perseverative worrying and checking tasks, and the influence of specific negative moods on personal performance standards. The final study explores the impact of experimentally induced mood on a worry task when the mood source is made highly salient i.e. attributed to an obvious event or source. On a perseverative checking task, different negative mood and stop rule combinations were found not to affect participant performance. However, using a personally-relevant worry task, participants in each specific negative mood condition persevered for longer using an “as many as can” rule compared with those using a “feel like continuing” rule. The opposite was found for participants in a happy mood. The effects of sadness and anxiety on personal performance standards and stop rule preference were also examined. Findings suggest a positive relationship between sad and anxious moods and “as many as can” stop rule preference. An attempt to manipulate mood attribution after inducing an angry mood showed marginally significant differences in attribution by the high and low manipulation groups, but no effects of mood attribution on task performance. These findings suggest that with a catastrophic worry task, participants in each specific negative mood condition using an “as many as can” stop rule persevered for longer compared with those using a “feel like continuing” stop rule. The implications of this work are discussed in relation to mood-as-input accounts of perseveration and models of mood

What’s worrying our students? Increasing worry levels over two decades and a new measure of student worry frequency and domains

Background The frequency and severity of mental health problems in student populations have been a growing cause for concern worldwide, and studies have identified measures of a number of mental health symptoms that have been steadily increasing in frequency and intensity over the past 20–25 years. Methods In two studies we investigate the levels and domains of pathological worrying in university student participants. Study 1 is a retrospective study of Penn State Worry Questionnaire (PSWQ) data collected between 2001 and 2019. Study 2 describes the development of the Student Worry Questionnaire, a short and easily delivered measure of student worrying that identifies both frequency of worry as well as the student-relevant domains across which worrying occurs. Results Study 1 revealed a steady increase in student worry scores of around 20% between 2001 and 2019, with a significant positive correlation between year of data collection and mean PSWQ score. The domain scores in Study 2 indicated that academic work was a significantly higher worry than any of the other domains, and worries about intimate relationships and ‘what people think of me’ were also worries that scored higher than either financial or health worries. Conclusions The present studies indicate that pathological worrying can be added to the list of anxiety- and stress-related symptoms that have been shown to be on the increase in student populations in recent decades, and we discuss whether these increases represent a greater willingness to report symptoms or a genuine increase in experienced symptoms over time

Alterations in amygdala-prefrontal functional connectivity account for excessive worry and autonomic dysregulation in generalized anxiety disorder

Background: Generalized anxiety disorder (GAD) is characterized by the core symptom of uncontrollable worry. Functional magnetic resonance imaging studies link this symptom to aberrant functional connectivity between the amygdala and prefrontal cortex. Patients with GAD also display a characteristic pattern of autonomic dysregulation. Although frontolimbic circuitry is implicated in the regulation of autonomic arousal, no previous study to our knowledge combined functional magnetic resonance imaging with peripheral physiologic monitoring in these patients to test the hypothesis that core symptoms of worry and autonomic dysregulation in GAD arise from a shared underlying neural mechanism. Methods: We used resting-state functional magnetic resonance imaging and the measurement of parasympathetic autonomic function (heart rate variability) in 19 patients with GAD and 21 control subjects to define neural correlates of autonomic and cognitive responses before and after induction of perseverative cognition. Seed-based analyses were conducted to quantify brain changes in functional connectivity with the right and left amygdala. Results: Before induction, patients showed relatively lower connectivity between the right amygdala and right superior frontal gyrus, right paracingulate/anterior cingulate cortex, and right supramarginal gyrus than control subjects. After induction, such connectivity patterns increased in patients with GAD and decreased in control subjects, and these changes tracked increases in state perseverative cognition. Moreover, decreases in functional connectivity between the left amygdala and subgenual cingulate cortex and between the right amygdala and caudate nucleus predicted the magnitude of reduction in heart rate variability after induction. Conclusions: Our results link functional brain mechanisms underlying worry and rumination to autonomic dyscontrol, highlighting overlapping neural substrates associated with cognitive and autonomic responses to the induction of perseverative cognitions in patients with GAD

Computerized exposure therapy for Spider Phobia: Effects of cardiac timing and interoceptive ability on subjective and behavioral outcomes

Objective: Spider phobia is a common form of anxiety disorder for which exposure therapy is an effective first-line treatment. Motivated by the observed modulation of threat processing by afferent cardiac signals; we tested the hypothesis that interoceptive information concerning cardiovascular arousal can influence the outcomes of computerised exposure therapy for spider phobia. Method: Fifty-three normal healthy participants with high spider phobia scores underwent one of three modified computerised exposure protocols, defined by the timing of exposure to brief spider stimuli within the cardiac cycle: Systole (during afferent baroreceptor firing); Diastole (during baroreceptor-quiescent interbeat interval); Random (non-contingent on cardiac cycle). Outcomes were judged on phobic and anxiety measures and physiological data (skin conductance). Subjects were also rated on interoceptive accuracy. Results: Mancova analysis showed that timing group affected the outcome measures (F(10,80)=2.405, p=0.015) and there was a group interaction with interoception ability (F(15,110)=1.808, p=0.045). Subjective symptom reduction (SPQ) was greatest in the Systolic group relative to the other two groups (Diastolic (t=3.115, ptukey=0.009); Random (t=2.438, ptukey=0.048), with greatest reductions in those participants with lower interoceptive accuracy. Behavioural aversion (BAT) reduced more in cardiac-contingent groups than the non-contingent (Random) group (Diastolic (t=3.295, ptukey=0.005); Systolic (t=2.602, ptukey=0.032). Physiological (SCR) responses remained strongest for spider stimuli presented at cardiac systole. Conclusion: Interoceptive information influences exposure benefit. The reduction in the subjective expression of fear/phobia is facilitated by ‘bottom-up’ afferent signals; while improvement in the behavioural expression is further dependent on ‘top-down’ representation of Interoceptive effects in spider phobia treatment self-related physiology (heart rhythm). Individual interoceptive differences moderate these effects, suggesting means to personalise therapy

Evaluation of a brief 4-session psychoeducation procedure for high worriers based on the mood-as-input hypothesis

Given the ubiquity of worrying as a consuming and distressing activity at both clinical and sub-clinical levels, it is important to develop theory-driven procedures that address worrying and allow worriers to manage this activity. This paper describes the development and testing of a psychoeducation procedure based on mood-as-input hypothesis, which is a transdiagnostic model that describes a proximal mechanism for perseverative worrying. The study used nonclinical participants meeting IAPT criteria indicating GAD symptomatology. In 4 sessions, participants in experimental groups received psychoeducation about the basic principles of the mood-as-input hypothesis and received guidance on how to identify and change worry-relevant goal-directed decision rules and negative moods. Participants in the psychoeducation conditions were compared with participants in a befriending control group. Psychoeducation about the model significantly reduced PSWQ scores at follow-up compared with the befriending control condition (a between-groups large effect size, Cohen's d = 1.05), and the homework tasks undertaken by the psychoeducation groups raised mood and reduced worry immediately. At follow up 48.2% of participants in the psychoeducation groups were below the recommended cut-off for identifying GAD symptomatology compared with 20% of participants in the control condition. This study was conducted on a small sample, high-worry student population, without a formal diagnosis. This brief, low-intensity procedure is potentially adaptable to online or self-help procedures, and can be integrated into fuller cognitive therapy packages

Network abnormalities in generalized anxiety pervade beyond the amygdala-prefrontal cortex circuit: insights from graph theory

Generalized anxiety (GAD) has excessive anxiety and uncontrollable worry as core symptoms. Abnormal cerebral functioning underpins the expression and perhaps pathogenesis of GAD: Studies implicate impaired communication between the amygdala and the pre-frontal cortex (PFC). Our aim was to longitudinally investigate whether such network abnormalities are spatially restricted to this circuit or if the integrity of functional brain networks is globally disrupted in GAD. We acquired resting-state functional magnetic resonance imaging data from 16 GAD patients and 16 matched controls at baseline and after 1 year. Using network modelling and graph-theory, whole-brain connectivity was characterized from local and global perspectives. Overall lower global efficiency, indicating sub-optimal brain-wide organization and integration, was present in patients with GAD compared to controls. The amygdala and midline cortices showed higher betweenness centrality, reflecting functional dominance of these brain structures. Third, lower betweenness centrality and lower degree emerged for PFC, suggesting weakened inhibitory control. Overall, network organization showed impairments consistent with neurobiological models of GAD (involving amygdala, PFC, and cingulate cortex) and further pointed to an involvement of temporal regions. Such impairments tended to progress over time and predict anxiety symptoms. A graph-analytic approach represents a powerful approach to deepen our understanding of GAD

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

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 self-reported 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