Katherine Pugh
University of Oxford
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British Journal of Psychiatry | 2008
Daniel Freeman; Katherine Pugh; Angus Antley; Mel Slater; Paul Bebbington; Matthew Gittins; Graham Dunn; Elizabeth Kuipers; David Fowler; Philippa Garety
BACKGROUND Judging whether we can trust other people is central to social interaction, despite being error-prone. A fear of others can be instilled by the contemporary political and social climate. Unfounded mistrust is called paranoia, and in severe forms is a central symptom of schizophrenia. AIMS To demonstrate that individuals without severe mental illness in the general population experience unfounded paranoid thoughts, and to determine factors predictive of paranoia using the first laboratory method of capturing the experience. METHOD Two hundred members of the general public were comprehensively assessed, and then entered a virtual reality train ride populated by neutral characters. Ordinal logistic regressions (controlling for age, gender, ethnicity, education, intellectual functioning, socio-economic status, train use, playing of computer games) were used to determine predictors of paranoia. RESULTS The majority agreed that the characters were neutral, or even thought they were friendly. However, a substantial minority reported paranoid concerns. Paranoia was strongly predicted by anxiety, worry, perceptual anomalies and cognitive inflexibility. CONCLUSIONS This is the most unambiguous demonstration of paranoid ideation in the general public so far. Paranoia can be understood in terms of cognitive factors. The use of virtual reality should lead to rapid advances in the understanding of paranoia.
Journal of Abnormal Psychology | 2010
Daniel Freeman; Katherine Pugh; Natasha Vorontsova; Angus Antley; Mel Slater
A key problem in studying a hypothesized spectrum of severity of delusional ideation is determining that ideas are unfounded. The first objective was to use virtual reality to validate groups of individuals with low, moderate, and high levels of unfounded persecutory ideation. The second objective was to investigate, drawing upon a cognitive model of persecutory delusions, whether clinical and nonclinical paranoia are associated with similar causal factors. Three groups (low paranoia, high nonclinical paranoia, persecutory delusions) of 30 participants were recruited. Levels of paranoia were tested using virtual reality. The groups were compared on assessments of anxiety, worry, interpersonal sensitivity, depression, anomalous perceptual experiences, reasoning, and history of traumatic events. Virtual reality was found to cause no side effects. Persecutory ideation in virtual reality significantly differed across the groups. For the clear majority of the theoretical factors there were dose–response relationships with levels of paranoia. This is consistent with the idea of a spectrum of paranoia in the general population. Persecutory ideation is clearly present outside of clinical groups and there is consistency across the paranoia spectrum in associations with important theoretical variables.
The Lancet Psychiatry | 2015
Daniel Freeman; Graham Dunn; Helen Startup; Katherine Pugh; Jacinta Cordwell; Helen Mander; Emma Černis; Gail Wingham; Katherine Shirvell; David Kingdon
Summary Background Worry might be a contributory causal factor in the occurrence of persecutory delusions in patients with psychotic disorders. Therefore we postulated that reducing worry with cognitive behaviour therapy (CBT) would reduce persecutory delusions. Methods For our two-arm, assessor-blinded, randomised controlled trial (Worry Intervention Trial [WIT]), we recruited patients aged 18–65 years with persistent persecutory delusions but non-affective psychosis from two centres: the Oxford Health National Health Service (NHS) Foundation Trust (Oxford, UK) and the Southern Health NHS Foundation Trust (Southampton, UK). The key inclusion criteria for participants were a score of at least 3 on the Psychotic Symptoms Rating Scale (PSYRATS) denoting a current persecutory delusion; that the delusion had persisted for at least 3 months; a clinical diagnosis of schizophrenia, schizoaffective disorder, or delusional disorder; and a clinically significant level of worry. We randomly assigned (1:1) eligible patients, using a randomly permuted block procedure with variable block sizes and division by four strata, to either six sessions of worry-reduction CBT intervention done over 8 weeks added to standard care (the CBT-intervention group), or to standard care alone (the control group). The assessors were masked to patient allocations and did their assessments at week 0 (baseline), 8 weeks (end of treatment), and 24 weeks, follow-up. The primary outcomes were worry measured by the Penn State Worry Questionnaire (PSWQ) and delusions measured by the PSYRATS-delusion scale; we did the analyses in the intention-to-treat population, and also did a planned mediation analysis. This trial is registered with the ISRCTN Registry (number ISRCTN23197625) and is closed to new participants. Findings From Nov 1, 2011, to Sept 9, 2013, we recruited 150 eligible participants and randomly assigned 73 to the CBT intervention group, and 77 to the control group. 143 patients (95%) provided primary outcome follow-up data. Compared with standard care alone, at 8 weeks the CBT intervention significantly reduced worry (mean difference 6·35 [SE 1·56] PSWQ units, 95% CI 3·30–9·40; p<0·001) and persecutory delusions (2·08 [SE 0·73] PSYRATS units, 95% CI 0·64–3·51; p=0·005). The reductions were maintained to 24 weeks follow-up. The mediation analysis suggested that the change in worry accounted for 66% of the change in delusion. No patients died or were admitted to secure units during our study. Six suicide attempts (two in the CBT intervention group, and four in the control group) and two serious violent incidents (one in each group) were noted, but no adverse events were deemed related to the treatments or the assessments. Interpretation To our knowledge, this is the first large trial focused on persecutory delusions. We have shown that long-standing delusions were significantly reduced by a brief intervention targeted on worry, although the limitations for our study include no determination of the key elements within the intervention. Our results suggest that worry might cause paranoia, and that worry intervention techniques might be a beneficial addition to the standard treatment of psychosis. Funding Efficacy and Mechanism Evaluation programme, which is a UK Medical Research Council and National Institute of Health Research partnership.
Schizophrenia Research | 2009
Daniel Freeman; Katherine Pugh; Natasha Vorontsova; Laura Southgate
Insomnia is a potential cause of anxiety, depression, and anomalies of experience; separate research has shown that anxiety, depression and anomalies of experience are predictors of paranoia. Thus insomnia may contribute to the formation and maintenance of persecutory ideation. The aim was to examine for the first time the association of insomnia symptoms and paranoia in the general population and the extent of insomnia in individuals with persecutory delusions attending psychiatric services. Assessments of insomnia, persecutory ideation, anxiety, and depression were completed by 300 individuals from the general population and 30 individuals with persecutory delusions and a diagnosis of non-affective psychosis. Insomnia symptoms were clearly associated with higher levels of persecutory ideation. Consistent with the theoretical understanding of paranoia, the association was partly explained by the presence of anxiety and depression. Moderate or severe insomnia was present in more than 50% of the delusions group. The study provides the first direct evidence that insomnia is common in individuals with high levels of paranoia. It is plausible that sleep difficulties contribute to the development of persecutory ideation. The intriguing implication is that insomnia interventions for this group could have the added benefit of lessening paranoia.
Psychological Medicine | 2008
Daniel Freeman; Matthew Gittins; Katherine Pugh; Angus Antley; Mel Slater; Graham Dunn
Background In recent years a close association between anxiety and persecutory ideation has been established, contrary to the traditional division of neurosis and psychosis. Nonetheless, the two experiences are distinct. The aim of this study was to identify factors that distinguish the occurrence of social anxiety and paranoid thoughts in an experimental situation. Method Two hundred non-clinical individuals broadly representative of the UK general population were assessed on a range of psychological factors, experienced a neutral virtual reality social environment, and then completed state measures of paranoia and social anxiety. Clustered bivariate logistic regressions were carried out, testing interactions between potential predictors and the type of reaction in virtual reality. Results The strongest finding was that the presence of perceptual anomalies increased the risk of paranoid reactions but decreased the risk of social anxiety. Anxiety, depression, worry and interpersonal sensitivity all had similar associations with paranoia and social anxiety. Conclusions The study shows that social anxiety and persecutory ideation share many of the same predictive factors. Non-clinical paranoia may be a type of anxious fear. However, perceptual anomalies are a distinct predictor of paranoia. In the context of an individual feeling anxious, the occurrence of odd internal feelings in social situations may lead to delusional ideas through a sense of ‘things not seeming right’. The study illustrates the approach of focusing on experiences such as paranoid thinking rather than diagnoses such as schizophrenia.
Journal of Nervous and Mental Disease | 2007
Daniel Freeman; Katherine Pugh; Catherine M. Green; Lucia Valmaggia; Graham Dunn; Philippa Garety
Experimental research is increasingly important in developing the understanding of paranoid thinking. An assessment measure of persecutory ideation is necessary for such work. We report the reliability and validity of the first state measure of paranoia: The State Social Paranoia Scale. The items in the measure conform to a recent definition in which persecutory thinking has the 2 elements of feared harm and perpetrator intent. The measure was tested with 164 nonclinical participants and 21 individuals at high risk of psychosis with attenuated positive symptoms. The participants experienced a social situation presented in virtual reality and completed the new measure. The State Social Paranoia Scale was found to have excellent internal reliability, adequate test-retest reliability, clear convergent validity as assessed by both independent interviewer ratings and self-report measures, and showed divergent validity with measures of positive and neutral thinking. The measure of paranoia in a recent social situation has good psychometric properties.
Schizophrenia Research | 2014
Daniel Freeman; Katherine Pugh; Graham Dunn; Nicole Evans; Bryony Sheaves; Felicity Waite; Emma Černis; Rachel Lister; David Fowler
Background Research has shown that paranoia may directly build on negative ideas about the self. Feeling inferior can lead to ideas of vulnerability. The clinical prediction is that decreasing negative self cognitions will reduce paranoia. Method Thirty patients with persistent persecutory delusions were randomised to receive brief CBT in addition to standard care or to standard care (ISRCTN06118265). The six session intervention was designed to decrease negative, and increase positive, self cognitions. Assessments at baseline, 8 weeks (posttreatment) and 12 weeks were carried out by a rater blind to allocation. The primary outcomes were posttreatment scores for negative self beliefs and paranoia. Secondary outcomes were psychological well-being, positive beliefs about the self, persecutory delusions, social comparison, self-esteem, anxiety, and depression. Results Trial recruitment and retention were feasible and the intervention highly acceptable to the patients. All patients provided follow-up data. Posttreatment there was a small reduction in negative self beliefs (Cohens d = 0.24) and a moderate reduction in paranoia (d = 0.59), but these were not statistically significant. There were statistically significant improvements in psychological well-being (d = 1.16), positive beliefs about the self (d = 1.00), negative social comparison (d = 0.88), self-esteem (d = 0.62), and depression (d = 0.68). No improvements were maintained. No adverse events were associated with the intervention. Conclusions The intervention produced short-term gains consistent with the prediction that improving cognitions about the self will reduce persecutory delusions. The improvement in psychological well-being is important in its own right. We recommend that the different elements of the intervention are tested separately and that the treatment is lengthened.
Journal of Psychiatric Research | 2013
Daniel Freeman; Helen Startup; Graham Dunn; Emma Černis; Gail Wingham; Katherine Pugh; Jacinta Cordwell; David Kingdon
Worry has traditionally been considered in the study of common emotional disorders such as anxiety and depression, but recent studies indicate that worry may be a causal factor in the occurrence and persistence of persecutory delusions. The effect of worry on processes traditionally associated with psychosis has not been tested. The aim of the study was to examine the short-term effects of a bout of worry on three cognitive processes typically considered markers of psychosis: working memory, jumping to conclusions, and anomalous internal experience. Sixty-seven patients with persecutory delusions in the context of a non-affective psychotic disorder were randomised to a worry induction, a worry reduction, or a neutral control condition. They completed tests of the cognitive processes before and after the randomisation condition. The worry induction procedure led to a significant increase in worry. The induction of worry did not affect working memory or jumping to conclusions, but it did increase a range of mild anomalous experiences including feelings of unreality, perceptual alterations, and temporal disintegration. Worry did not affect the occurrence of hallucinations. The study shows that a period of worry causes a range of subtle odd perceptual disturbances that are known to increase the likelihood of delusions. It demonstrates an interaction between affective and psychotic processes in patients with delusions.
The Lancet Psychiatry | 2017
Daniel Freeman; Bryony Sheaves; Guy M. Goodwin; Ly-Mee Yu; Alecia Nickless; Paul J. Harrison; Richard Emsley; Annemarie I. Luik; Russell G. Foster; Vanashree Wadekar; Chris Hinds; Andrew Gumley; Ray Jones; Stafford L. Lightman; Steve Jones; Richard P. Bentall; Peter Kinderman; Georgina Rowse; Traolach S. Brugha; Mark Blagrove; Alice M. Gregory; Leanne Fleming; Elaine Walklet; Cris Glazebrook; E. Bethan Davies; Chris Hollis; Gillian Haddock; Bev John; Mark Coulson; David Fowler
Summary Background Sleep difficulties might be a contributory causal factor in the occurrence of mental health problems. If this is true, improving sleep should benefit psychological health. We aimed to determine whether treating insomnia leads to a reduction in paranoia and hallucinations. Methods We did this single-blind, randomised controlled trial (OASIS) at 26 UK universities. University students with insomnia were randomly assigned (1:1) with simple randomisation to receive digital cognitive behavioural therapy (CBT) for insomnia or usual care, and the research team were masked to the treatment. Online assessments took place at weeks 0, 3, 10 (end of therapy), and 22. The primary outcome measures were for insomnia, paranoia, and hallucinatory experiences. We did intention-to-treat analyses. The trial is registered with the ISRCTN registry, number ISRCTN61272251. Findings Between March 5, 2015, and Feb 17, 2016, we randomly assigned 3755 participants to receive digital CBT for insomnia (n=1891) or usual practice (n=1864). Compared with usual practice, the sleep intervention at 10 weeks reduced insomnia (adjusted difference 4·78, 95% CI 4·29 to 5·26, Cohens d=1·11; p<0·0001), paranoia (−2·22, −2·98 to −1·45, Cohens d=0·19; p<0·0001), and hallucinations (−1·58, −1·98 to −1·18, Cohens d=0·24; p<0·0001). Insomnia was a mediator of change in paranoia and hallucinations. No adverse events were reported. Interpretation To our knowledge, this is the largest randomised controlled trial of a psychological intervention for a mental health problem. It provides strong evidence that insomnia is a causal factor in the occurrence of psychotic experiences and other mental health problems. Whether the results generalise beyond a student population requires testing. The treatment of disrupted sleep might require a higher priority in mental health provision. Funding Wellcome Trust.
Psychiatry Research-neuroimaging | 2016
Nicola Collett; Katherine Pugh; Felicity Waite; Daniel Freeman
There has been growing awareness of the high prevalence of negative cognitions about the self in patients with persecutory delusions, and it has been proposed that paranoid fears build upon these perceived vulnerabilities. This study aimed to investigate for the first time a wide range of different conceptualisations of the negative self, and to examine associations with suicidal ideation, in patients with persecutory delusions. Twenty-one patients with persecutory delusions and twenty-one non-clinical individuals completed measures relating to negative self cognitions. The delusions group also completed a measure of suicidal ideation. It was found that the patients with persecutory delusions had low self-compassion, low self-esteem, increased fears of being mad, beliefs of inferiority to others, negative self-schemas, and low positive self-schemas when compared to the non-clinical control group. The effect sizes (Cohens d) were large, and the different conceptualisations of negative self cognitions were highly associated with one another. Self-stigma did not differ between the two groups. Furthermore, suicidal ideation was highly associated with low self-compassion, low self-esteem, fears of madness, and negative self-schema but not self-stigma. This study shows marked negative self cognitions in patients with persecutory delusions. These are likely to prove targets of clinical interventions, with patient preference most likely determining the best conceptualisation of negative self cognitions for clinicians to use.