The psychological effect of an urban environment on individuals with persecutory delusions: the Camberwell walk study

BACKGROUND: Epidemiological studies have found that individuals who live in urban areas are at increased risk of developing psychosis. However it is unknown whether exposure to urban environments exacerbates psychotic symptoms in people who have a diagnosed psychotic disorder. The aim of the study was to examine the psychological and clinical effects of exposure to one specific deprived urban environment on individuals with persecutory delusions. It was predicted that the urban environment would affect emotional and reasoning processes highlighted in a cognitive model of persecutory delusions and would increase paranoia. METHOD: Thirty patients with persecutory delusions were randomised to exposure to a deprived urban environment or to a brief mindfulness relaxation task. After exposure, assessments of symptoms, reasoning, and affective processes were taken. Thirty matched non-clinical participants also completed the study measures to enable interpretation of the test scores. RESULTS: In individuals with persecutory delusions, exposure to the urban environment, rather than participation in a mindfulness task, increased levels of anxiety, negative beliefs about others and jumping to conclusions. It also increased paranoia. The individuals with persecutory delusions scored significantly differently from the non-clinical group on all measures. CONCLUSIONS: For individuals with psychosis, spending time in an urban environment makes them think more negatively about other people and increases anxiety and the jumping to conclusions reasoning bias. Their paranoia is also increased. A number of processes hypothesised in cognitive models to lead to paranoid thoughts are exacerbated by a deprived urban environment. Further research is needed to clarify which aspects of urban environments cause the negative effects. Methodological challenges in the research area are raised.     

Advances in understanding and treating persecutory delusions: a review

Purpose

Persecutory delusions are a central psychotic experience, at the severe end of a paranoia spectrum in the general population. The aim of the review is to provide an introduction to the understanding of persecutory delusions, highlight key putative causal factors that have the potential to be translated into efficacious treatment, and indicate future research directions.

Methods

A narrative literature review was undertaken to highlight the main recent areas of empirical study concerning non-clinical and clinical paranoia.

Results

Six main proximal causal factors are identified: a worry thinking style, negative beliefs about the self, interpersonal sensitivity, sleep disturbance, anomalous internal experience, and reasoning biases. Each has plausible mechanistic links to the occurrence of paranoia. These causal factors may be influenced by a number of social circumstances, including adverse events, illicit drug use, and urban environments.

Conclusions

There have been numerous replicated empirical findings leading to a significant advance in the understanding of persecutory delusions, now beginning to be translated into cognitive treatments. The first trials specifically focussed on patients who have persecutory delusions in the context of psychotic diagnoses are occurring. Initial evidence of efficacy is very promising.     

Attentional and memory bias in persecutory delusions and depression

BACKGROUND: Previous research has indicated that persecutory delusions and depression may share similar cognitive biases at implicit levels of processing, but differentiate at explicit levels, supporting the theory that paranoia may have a protective function against underlying negative schemata. The study aimed to investigate attentional bias and both implicit and explicit memory biases for personally salient and standardised emotional stimuli in persecutory delusions and depression. SAMPLING: 36 participants, with 12 in each group, were interviewed in order to generate personally salient stimuli to be employed within the cognitive tests. Standardised emotional stimuli were additionally employed as a control. Participants completed two probe detection tasks, one including personally salient stimuli and one including standard emotional stimuli. Memory for the stimuli presented in this task was assessed by a free recall task (explicit memory) followed by a word completion task (implicit memory). RESULTS: On an implicit memory task, both the deluded and depressed groups displayed comparable retrieval of positive and negative words. However, on the explicit memory task, the depressed group demonstrated a bias for negative stimuli, whereas the deluded group demonstrated a bias for positive stimuli. The groups did not demonstrate an attentional bias for personally salient information. However, an attentional bias for standardised emotional stimuli was found in the depressed group, although this was not specific to either negative or positive stimuli. CONCLUSION: The results indicate that depression and persecutory delusions may share similar patterns of processing at an implicit level but differentiate at the explicit level, which may be indicative of cognitive avoidance of threatening stimuli in psychosis. However, this does not seem to be a feature of automatic attentional processes in people with persecutory delusions. Implications for further research are discussed.     

Current Paranoid Thinking in Patients With Delusions: The Presence of Cognitive-Affective Biases

Background: There has been renewed interest in the influence of affect on psychosis. Psychological research on persecutory delusions ascribes a prominent role to cognitive processes related to negative affect: anxiety leads to the anticipation of threat within paranoia; depressive negative ideas about the self create a sense of vulnerability in which paranoid thoughts flourish; and self-consciousness enhances feelings of the self as a target. The objective of this study was to examine such affective processes in relation to state paranoia in patients with delusions. Methods: 130 patients with delusions in the context of a nonaffective psychosis diagnosis (predominately schizophrenia) were assessed for contemporaneous levels of persecutory ideation on 5 visual analog scales. Measures were taken of anxiety, depression, threat anticipation, interpretation of ambiguity, self-focus, and negative ideas about the self. Results: Of the patients, 85% report paranoid thinking at testing. Symptoms of anxiety and depression were highly prevalent. Current paranoid thinking was associated with anxiety, depression, greater anticipation of threat events, negative interpretations of ambiguous events, a self-focused cognitive style, and negative ideas about the self. Conclusions: The study provides a clear demonstration that a range of emotion-related cognitive biases, each of which could plausibly maintain delusions, are associated with current paranoid thinking in patients with psychosis. We identified biases both in the contents of cognition and in the processing of information. Links between affect and psychosis are central to the understanding of schizophrenia. We conclude that treatment of emotional dysfunction should lead to reductions in current psychotic experiences.Key words: delusions, paranoia, cognition, anxiety, depression, schizophrenia     

Virtual reality and persecutory delusions: safety and feasibility

OBJECTIVE: Virtual reality (VR) has begun to be used to research the key psychotic symptom of paranoia. The initial studies have been with non-clinical individuals and individuals at high risk of psychosis. The next step is to develop the technology for the understanding and treatment of clinical delusions. Therefore the present study investigated the acceptability and safety of using VR with individuals with current persecutory delusions. Further, it set out to determine whether patients feel immersed in a VR social environment and, consequently, experience paranoid thoughts. METHOD: Twenty individuals with persecutory delusions and twenty non-clinical individuals spent 4 min in a VR underground train containing neutral characters. Levels of simulator sickness, distress, sense of presence, and persecutory ideation about the computer characters were measured. A one-week follow-up was conducted to check longer-term side effects. RESULTS: The VR experience did not raise levels of anxiety or symptoms of simulator sickness. No side effects were reported at the follow-up. There was a considerable degree of presence in the VR scenario for all participants. A high proportion of the persecutory delusions group (65%) had persecutory thinking about the computer characters, although this rate was not significantly higher than the non-clinical group. CONCLUSIONS: The study indicates that brief experiences in VR are safe and acceptable to people with psychosis. Further, patients with paranoia can feel engaged in VR scenes and experience persecutory thoughts. Exposure to social situations using VR has the potential to be incorporated into cognitive behavioural interventions for paranoia.     

Genotype-phenotype studies in bipolar disorder showing association between the DAOA/G30 locus and persecutory delusions: a first step toward a molecular genetic classification of psychiatric phenotypes

OBJECTIVE: The authors previously reported an association between the D-amino acid oxidase activator (DAOA)/G30 locus and both schizophrenia and bipolar affective disorder. Given the presumed role of DAOA/G30 in the neurochemistry of psychosis and its localization in a schizophrenia and bipolar affective disorder linkage region (13q34), it was hypothesized that the bipolar affective disorder finding would be mainly due to an association with psychotic features. METHOD: The marker/haplotype associations obtained in a subset of 173 bipolar affective disorder patients with psychotic features were similar to those in the overall patient group, suggesting that stratification on the basis of psychotic features in general might be too crude a procedure. The authors therefore tested whether confining caseness to specific psychotic features would improve detection of genotype-phenotype correlations. RESULTS: In a logistic regression, "persecutory delusions" were found to be the only significant explanatory variable for the DAOA/G30 risk genotype among 21 OPCRIT symptoms of psychosis. The authors therefore tested for association between DAOA/G30 and bipolar affective disorder in the 90 cases with a history of persecutory delusions. Whereas this subset showed strong association (odds ratio=1.83 for the best marker), the remaining larger sample of 165 patients with no such history did not differ from comparison subjects, suggesting that the association between DAOA/G30 and bipolar affective disorder is due to persecutory delusions. This was confirmed in an independent study of 294 bipolar affective disorder patients and 311 comparison subjects from Poland, in which an association between bipolar affective disorder and DAOA/G30 was only seen when case definition was restricted to cases with persecutory delusions. CONCLUSIONS: These data suggest that bipolar affective disorder with persecutory delusions constitutes a distinct subgroup of bipolar affective disorder that overlaps with schizophrenia.     

Suicidal ideation and behaviour in patients with persecutory delusions: Prevalence,symptom associations,and psychological correlates

BackgroundTo determine the prevalence of suicidal ideation and behaviour - and their correlates - in patients with persecutory delusions.Methods110 patients with persecutory delusions in the context of non-affective psychosis were assessed for suicidal thoughts and behaviours over the past month. Symptom and psychological assessments were also completed.ResultsThe severity of suicidal ideation was: no suicidal ideation (n = 26, 23.6%); wish to be dead (n = 21, 19.1%); nonspecific active suicidal thoughts (n = 14, 12.7%); suicidal thoughts with methods but no intent (n = 29, 26.4%); suicidal thoughts with intent but no specific plan (n = 13, 11.8%); and suicidal intent with plan (n = 7, 6.4%). In the past month, five patients (4.5%) had made an actual, interrupted, or aborted suicide attempt. The severity of suicidal ideation was associated with higher levels of depression, paranoia, hallucinations, anger, insomnia, negative beliefs about the self and others, pessimism, worry, and delusion safety-seeking behaviours and lower levels of psychological well-being and reward responsiveness. Severity of ideation was not associated with cannabis or alcohol use, working memory, pain, or meaningful activity levels.ConclusionsPatients with persecutory delusions are typically in a severe state of psychological stress, and at risk of suicide, as indicated by very high levels of suicidal ideation. This exploratory study also identifies correlates of suicidal ideation that could be investigated in causal research designs.     

A pilot trial of cognitive behavioural therapy for interpersonal sensitivity in individuals with persecutory delusions

BackgroundAdvances in understanding delusions may be used to improve clinical interventions. Interpersonal sensitivity – feeling vulnerable in the presence of others due to the expectation of criticism or rejection – has been identified as a potential causal factor in the occurrence of persecutory delusions. The purpose of this study was to examine the potential impact on persecutory delusions of a (newly devised) cognitive behavioural intervention targeting interpersonal sensitivity (CBT-IPS).MethodsCBT-IPS was tested in an uncontrolled pilot study with eleven patients with persistent persecutory delusions in the context of a psychotic disorder. Patients had two baseline assessments over a fortnight period to establish the stability of the delusions, which was followed by six sessions of CBT-IPS, a post-therapy assessment, and a further follow-up assessment one month later.ResultsInterpersonal sensitivity and the persecutory delusions were stable during the baseline period. At the post-therapy assessment there were significant reductions of large effect size for both interpersonal sensitivity and the persecutory delusions. These gains were maintained at follow-up.LimitationsThe main limitation is that in this initial test there was no control group. The intervention may not have caused the reduction in delusions. Further, bias may have been introduced by the outcome data being collected by the therapist.ConclusionsThe findings from this evaluation are consistent with the hypothesised causal role for interpersonal sensitivity in the occurrence of persecutory delusions. CBT-IPS shows promise as a therapeutic intervention but requires a rigorous test of its efficacy.     

The journey to psychosis: an exploration of specific psychological pathways

Recent models of psychosis have implicated specific psychological processes in the aetiology of this disorder, and these factors may form a route to later symptoms—either directly or via a mediating pathway after exposure to adversity. Researchers are beginning to bring together findings that look into specific pathways between early experiences of adversity and different symptoms of psychosis, including thought disorder, hallucinations and persecutory delusions. The adversity-specific pathways include parental communication deviance, source monitoring biases, and insecure attachment. Researchers have also begun to utilise specific psychological factors as targets for treatment, and these include a focus on a worrying thinking style, negative beliefs about the self, interpersonal sensitivity, sleep disturbance, anomalous internal experience, and reasoning biases. Research on the impact of psychological processes is beginning to mount and is likely to improve our understanding of aetiology and lead to significant advances in the treatment of psychotic symptoms and disorders.     

Cognitive neuropsychiatric models of persecutory delusions

OBJECTIVE: The major cognitive theories of persecutory delusion formation and maintenance are critically examined in this article. METHOD: The authors present a comprehensive review of the literature, citing results of relevant functional neuroimaging and neural network studies. RESULTS: People with persecutory delusions selectively attend to threatening information, jump to conclusions on the basis of insufficient information, attribute negative events to external personal causes, and have difficulty in envisaging others' intentions, motivations, or states of mind. Presence of the "reality distortion" cluster of psychotic symptoms correlates with cerebral blood flow in the left lateral prefrontal cortex, ventral striatum, superior temporal gyrus, and parahippocampal region. Social cognitive processing (selective attention to threat, attribution of causation or mental states) in normal subjects involves similar areas. Neural network models of persecutory delusions highlight the importance of disordered neuromodulation in their formation and of disordered neuroplasticity in their maintenance. CONCLUSIONS: Further studies examining the interaction of these cognitive processes, cross-sectionally and longitudinally, at cognitive psychological, neural network, and functional neuroanatomical levels are warranted to establish a comprehensive cognitive neuropsychiatric model of the persecutory delusion.     

Postictal Psychosis: A Comparison with Acute Interictal and Chronic Psychoses

Summary: We studied 30 patients with postictal psychosis and compared them with 33 patients with acute interictal psychosis and 25 patients with chronic psychosis. All patients had either complex partial seizures (CPS) or EEG temporal epileptogenic foci. Patients with postictal psychosis had a high incidence of psychic auras and nocturnal secondarily generalized seizures. The most striking feature that distinguished postictal psychosis from both acute interictal and chronic psychoses was phenomenological: the relatively frequent occurrence of grandiose delusions as well as religious delusions in the setting of markedly elevated moods and feeling of mystic fusion of the body with the universe. In addition, postictal psychosis exhibited few schizophreniform psychotic traits such as perceptual delusions or voices commenting. Reminiscence, mental diplopia, and a feeling of impending death were also fairly frequent complaints of patients with postictal psychosis. Interictal acute psychosis and chronic epileptic psychosis were psychopathologically similar. Although acute interictal and chronic epileptic psychoses could simulate schizophrenia, postictal psychosis results in a mental state quite different from that of schizophrenic psychosis.     

How Cannabis Causes Paranoia: Using the Intravenous Administration of ?9-Tetrahydrocannabinol (THC) to Identify Key Cognitive Mechanisms Leading to Paranoia

Paranoia is receiving increasing attention in its own right, since it is a central experience of psychotic disorders and a marker of the health of a society. Paranoia is associated with use of the most commonly taken illicit drug, cannabis. The objective was to determine whether the principal psychoactive ingredient of cannabis—∆⁹-tetrahydrocannabinol (THC)—causes paranoia and to use the drug as a probe to identify key cognitive mechanisms underlying paranoia. A randomized, placebo-controlled, between-groups test of the effects of intravenous THC was conducted. A total of 121 individuals with paranoid ideation were randomized to receive placebo, THC, or THC preceded by a cognitive awareness condition. Paranoia was assessed extensively via a real social situation, an immersive virtual reality experiment, and standard self-report and interviewer measures. Putative causal factors were assessed. Principal components analysis was used to create a composite paranoia score and composite causal variables to be tested in a mediation analysis. THC significantly increased paranoia, negative affect (anxiety, worry, depression, negative thoughts about the self), and a range of anomalous experiences, and reduced working memory capacity. The increase in negative affect and in anomalous experiences fully accounted for the increase in paranoia. Working memory changes did not lead to paranoia. Making participants aware of the effects of THC had little impact. In this largest study of intravenous THC, it was definitively demonstrated that the drug triggers paranoid thoughts in vulnerable individuals. The most likely mechanism of action causing paranoia was the generation of negative affect and anomalous experiences.Key words: paranoia, delusions, cannabis, THC, cognitive     

A randomised controlled trial of a worry intervention for individuals with persistent persecutory delusions

Recent research has shown that worry is associated with distressing paranoia. Therefore, the aim was to target worry in a therapeutic intervention for individuals with delusions. It was predicted that a worry intervention would reduce levels of worry and paranoia distress. Twenty-four individuals with persistent persecutory delusions and high levels of worry were randomly assigned to receive a four session cognitive-behavioural worry intervention (W-CBT) or treatment as usual (TAU). The worry intervention was specifically designed not to target the content of delusions. In this open-label evaluation, assessments of worry and paranoia were conducted at baseline, at one month (end of treatment) and at two months. The worry intervention achieved a statistically significant reduction in worry which was maintained at two month follow up. A significant reduction in delusional distress was also reported. There was an indication that the worry intervention may also reduce the frequency of paranoid thoughts but this was not statistically significant. In the first trial specifically for persecutory delusions, a brief worry intervention was shown to have benefits. The results support a causal role for worry in paranoid experience.     

The psychology of persecutory ideation II: a virtual reality experimental study

A cognitive model of persecutory delusions is used to predict the occurrence of nonclinical paranoid thoughts in a virtual reality environment. Scorers across the range of paranoia entered a virtual reality scene populated by five computer characters programmed to behave neutrally (N = 30). Many appraisals of the computer characters were positive or neutral. However, there were also persecutory thoughts about the characters. Providing evidence of the validity of the experimental method, persecutory ideation was predicted by higher trait paranoia and a greater sense of presence in the environment. The psychological variables from the cognitive model that predicted persecutory ideation were anxiety, timidity, and hallucinatory predisposition. Further, hallucinatory predisposition distinguished the prediction of paranoid thoughts from social anxiety in virtual reality. It is concluded that nonclinical paranoid thoughts are most closely associated with emotional disturbances and anomalous experiences. Extreme reasoning bias may particularly contribute to the development of clinical phenomena.     

Improvement of both psychotic symptoms and Parkinsonism in a case of dementia with Lewy bodies by the combination therapy of risperidone and L-DOPA

A 69-year-old female of dementia with Lewy bodies (DLB) with fluctuating cognitive impairment, visual and auditory hallucinations, persecutory delusions and Parkinsonism was treated by the combination of 1 mg/day risperidone and 300-750 mg/day L-DOPA. By this combination therapy, both the psychotic symptoms and Parkinsonism improved, while cognitive function did not deteriorate. This report suggests that the combination therapy of risperidone and L-DOPA may be worth considering in the special cases of DLB.     

The psychology of persecutory ideation I: a questionnaire survey

Paranoia is a complex phenomenon that is likely to arise from a number of factors. In a recent cognitive model of persecutory delusions, three key factors are highlighted: anomalous experiences, emotion, and reasoning. In the first of two linked studies, we report a questionnaire survey of nonclinical paranoia designed to assess the theoretical model. A nonclinical population (N = 327) completed measures of paranoia, anomalous experiences (hallucinatory predisposition, perceptual anomalies), emotion (depression, anxiety, self-focus, stress, interpersonal sensitivity), and reasoning (need for closure). Paranoia was best explained by separation anxiety, depression, fragile inner self, hallucinatory experiences, discomfort with ambiguity, stress, self-focus, perceptual anomalies, and anxiety. The findings are consistent with the central predictions within the model of paranoia.     

Emotion and psychosis: links between depression, self-esteem, negative schematic beliefs and delusions and hallucinations

BACKGROUND: The role of emotion in psychosis is being increasingly recognised. Cognitive conceptualisations of psychosis (e.g. [Garety, P.A., Kuipers, E.K., Fowler, D., Freeman, D., Bebbington, P.E., 2001. A cognitive model of the positive symptoms of psychosis. Psychological Medicine, 31, 189-195]) emphasise a central, normal, direct and non-defensive role for negative emotion in the development and maintenance of psychosis. This study tests specific predictions made by Garety et al. [Garety, P.A., Kuipers, E.K., Fowler, D., Freeman, D., Bebbington, P.E., 2001. A cognitive model of the positive symptoms of psychosis. Psychological Medicine, 31, 189-195] about the role of emotion and negative evaluative beliefs in psychosis. METHODS: 100 participants who had suffered a recent relapse in psychosis were recruited at baseline for the Prevention of Relapse in Psychosis (PRP) trial. In a cross-sectional analysis, we examined the role of depression, self-esteem and negative evaluative beliefs in relation to specific positive symptoms (persecutory delusions, auditory hallucinations and grandiose delusions) and symptom dimensions (e.g. distress, negative content, pre-occupation and conviction). RESULTS: Analysis indicated that individuals with more depression and lower self-esteem had auditory hallucinations of greater severity and more intensely negative content, and were more distressed by them. In addition, individuals with more depression, lower self-esteem and more negative evaluations about themselves and others had persecutory delusions of greater severity and were more pre-occupied and distressed by them. The severity of grandiose delusions was related inversely to depression scores and negative evaluations about self, and directly to higher self-esteem. CONCLUSIONS: This study provides evidence for the role of emotion in schizophrenia spectrum-disorders. Mood, self-esteem and negative evaluative beliefs should be considered when conceptualising psychosis and designing interventions.     

Neuropsychological functioning in first-break, never-medicated adolescents with psychosis

The purpose of the current study was to examine neuropsychological functioning in a group of never-medicated first-break adolescents with psychosis. It is the first report of cognition in a sample of adolescents with psychosis in which all patients were drug-naive. Twenty-nine adolescent patients (mean age = 16.07; SD = 2.00; 15 male and 14 female patients) experiencing their first psychotic episode and 17 age-matched and sex-matched normal volunteers (mean age = 16.88; SD = 2.39; 9 male and 8 female subjects) were recruited and assessed with a neuropsychological battery. Measures of attention, memory, language, executive functioning, perceptual motor processing, and motor speed were obtained. Psychiatric symptomatology, estimated verbal IQ, and parental socioeconomic status were also determined. Patients with psychosis were significantly more impaired than normal volunteers; effect sizes were greatest in the areas of executive functioning, attention, and memory, and significantly smaller in areas of language, perceptual motor processing, and motor speed. The pattern was not altered when differences in verbal IQ and parental socioeconomic status were controlled. Sex and age interactions indicated that younger male patients were particularly impaired. The findings demonstrate neuropsychological deficits in adolescents with psychosis and suggest that cognitive deficits are core symptoms in psychotic disorders.     

Are anomalous perceptual experiences necessary for delusions?

Several theories of delusions suggest that anomalous perceptual experience is necessary for delusion formation. This study evaluated levels of anomalous perceptual experience in a large group of nonclinical participants from the general population (N = 337), a group of psychotic inpatients (N = 20), and 2 groups of hallucinating (N = 24) and nonhallucinating (N = 24) deluded patients. The aims of the study were to evaluate the hypothesis that pathological levels of anomalous perceptual experience were necessarily associated with delusions. Using the Cardiff Anomalous Perceptions Scale, the main finding was that as a group, nonhallucinating deluded patients were not significantly different from nonclinical participants on any of the anomalous perceptual experience indices. We conclude that anomalous perceptual experience, as measured by the Cardiff Anomalous Perceptions Scale, is not necessary for the presence of delusions.     

Cognitive endophenotypes of psychosis within dimension and diagnosis

This study sought to characterize the psychosis phenotype, contrasting cognitive features within traditional diagnosis and psychosis dimension in a family sample containing both schizophrenia and psychotic bipolar I disorder. Seventy-six probands with psychosis [44 probands with schizophrenia, 32 probands with psychotic bipolar I disorder] and 55 first-degree relatives [30 relatives of schizophrenia probands, 25 relatives of bipolar probands] were recruited. Standardized clinical and neuropsychological measures were administered. No differences in cognitive performance emerged between probands with schizophrenia and probands with psychotic bipolar disorder, or between relatives of probands with schizophrenia and relatives of probands with bipolar disorder in the domains of working and declarative memory, executive function and attention. Relatives overall showed higher cognitive performance compared to probands, as expected. However, when we segmented the probands and relatives along a psychosis dimension, independent of diagnostic groups, results revealed lower cognitive performance in probands compared to relatives without psychosis spectrum disorders, whereas relatives with psychosis spectrum disorders showed an intermediate level of performance across all cognitive domains. In this study, cognitive performance did not distinguish either probands or their first-degree relatives within traditional diagnostic groups (schizophrenia and psychotic bipolar disorder), but distinguished probands and relatives with and without lifetime psychosis manifestations independent of diagnostic categories. These data support the notion that schizophrenia and psychotic bipolar disorder present a clinical continuum with overlapping cognitive features defining the psychosis phenotype.