Daniel Freeman

A cognitive model of the positive symptoms of psychosis

In the last 10 years a consensus has developed that the symptoms of psychosis may be better understood by linking the steps between the phenomenological experiences and social, psychological and neurobiological levels of explanation. Cognitive models of psychosis are an important link in this chain. They provide a psychological description of the phenomena from which hypotheses concerning causal processes can be derived and tested; social, individual, and neurobiological factors can then be integrated via their impact on these cognitive processes. In this paper, we set out the cognitive processes that we think lead to the formation and maintenance of the positive symptoms of psychosis and we attempt to integrate into our model research in social factors. If this model proves useful, a fuller integration with the findings of biological research will be required (Frith, 1992).

A cognitive model of persecutory delusions

A multifactorial model of the formation and maintenance of persecutory delusions is presented. Persecutory delusions are conceptualized as threat beliefs. The beliefs are hypothesized to arise from a search for meaning for internal or external experiences that are unusual, anomalous, or emotionally significant for the individual. The persecutory explanations formed reflect an interaction between psychotic processes, pre-existing beliefs and personality (particularly emotion), and the environment. It is proposed that the delusions are maintained by processes that lead to the receipt of confirmatory evidence and processes that prevent the processing of disconfirmatory evidence. Novel features of the model include the (non-defended) direct roles given to emotion in delusion formation, the detailed consideration of both the content and form of delusions, and the hypotheses concerning the associated emotional distress. The clinical and research implications of the model are outlined.

Connecting neurosis and psychosis: the direct influence of emotion on delusions and hallucinations.

Diagnostic classification systems contain a core divide between neurosis and psychosis, leading to their separate study and treatment. The basis for the separation of the disorders is outlined and reassessed. It is argued that the empirical evidence does not support such a sharp distinction between neurosis and psychosis. The frequent occurrence of emotional disorder prior to and accompanying psychosis indicates that neurosis contributes to the development of the positive symptoms of psychosis. Psychological theories and experimental evidence concerning the influence of emotion on the content and form of delusions and hallucinations are therefore reviewed. It is argued that in many cases delusions are a direct representation of emotional concerns, and that emotion contributes to delusion formation and maintenance. The content of hallucinations less often directly expresses the emotional concerns of the individual, but emotion can trigger and contribute to the maintenance of hallucinatory phenomena, although how this occurs is not well understood. It is concluded that study needs to be made of the interaction between psychotic and neurotic processes in the development of delusions and hallucinations, and that neurotic and psychotic disorders may have common maintenance processes.

Reasoning, emotions, and delusional conviction in psychosis

The aim of the study was to elucidate the factors contributing to the severity and persistence of delusional conviction. One hundred participants with current delusions, recruited for a treatment trial of psychological therapy (PRP trial), were assessed at baseline on measures of reasoning, emotions, and dimensions of delusional experience. Reasoning biases (belief inflexibility, jumping to conclusions, and extreme responding) were found to be present in one half of the sample. The hypothesis was confirmed that reasoning biases would be related to delusional conviction. There was evidence that belief inflexibility mediated the relationship between jumping to conclusions and delusional conviction. Emotional states were not associated with the reasoning processes investigated. Anxiety, but not depression, made an independent contribution to delusional conviction.

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.

Persecutory delusions: developing the understanding of belief maintenance and emotional distress.

BACKGROUND The objective of the study was to develop the cognitive understanding of persecutory delusions. It was hypothesized that safety behaviours contribute to the persistence of persecutory delusions by preventing disconfirmation. It was further hypothesized that emotional distress is associated with aspects of the content of delusions. An investigation was designed to establish whether individuals with persecutory delusions use safety behaviours, and to test predicted associations between delusion content and emotional distress. METHOD A cross-sectional investigation was conducted on 25 individuals with persecutory delusions. A detailed assessment was made of the presence of safety behaviours, the content of delusions and emotional distress. RESULTS All participants had used at least one safety behaviour in the last month, most typically avoidance. Higher levels of anxiety were associated with greater use of safety behaviours. New data were obtained on the content of persecutory delusions. Aspects of the content of the delusions were associated with levels of depression, self-esteem, anxiety and delusional distress. CONCLUSIONS Individuals with persecutory delusions use safety behaviours. The findings may develop the understanding of delusion persistence, acting upon delusions and the negative symptoms of schizophrenia. There are implications for cognitive interventions for psychosis. Support was also found for the hypothesis that emotional distress is linked to the content of delusional beliefs; it is speculated that prior emotional distress influences the content of delusions, and that delusion content in turn influences levels of emotional distress.

Implications for neurobiological research of cognitive models of psychosis: a theoretical paper

BACKGROUND Cognitive models of the positive symptoms of psychosis specify the cognitive, social and emotional processes hypothesized to contribute to their occurrence and persistence, and propose that vulnerable individuals make characteristic appraisals that result in specific positive symptoms. METHOD We describe cognitive models of positive psychotic symptoms and use this as the basis of discussing recent relevant empirical investigations and reviews that integrate cognitive approaches into neurobiological frameworks. RESULTS Evidence increasingly supports a number of the hypotheses proposed by cognitive models. These are that: psychosis is on a continuum; specific cognitive processes are risk factors for the transition from subclinical experiences to clinical disorder; social adversity and trauma are associated with psychosis and with negative emotional processes; and these emotional processes contribute to the occurrence and persistence of psychotic symptoms. There is also evidence that reasoning biases contribute to the occurrence of delusions. CONCLUSIONS The benefits of incorporating cognitive processes into neurobiological research include more sophisticated, bidirectional and interactive causal models, the amplification of phenotypes in neurobiological investigations by including emotional processes, and the adoption of more specific clinical phenotypes. For example, there is potential value in studying gene x environment x cognition/emotion interactions. Cognitive models and their derived phenotypes constitute the missing link in the chain between genetic or acquired biological vulnerability, the social environment and the expression of individual positive symptoms.

The Brief Core Schema Scales (BCSS): psychometric properties and associations with paranoia and grandiosity in non-clinical and psychosis samples.

BACKGROUND Traditional instruments that measure self-esteem may not relate directly to the schema construct as outlined in recent cognitive models. The Brief Core Schema Scales (BCSS) aim to provide a theoretically coherent self-report assessment of schemata concerning self and others in psychosis. The scales assess four dimensions of self and other evaluation: negative-self, positive-self, negative-other, positive-other. METHOD We analysed the psychometric properties of the BCSS using a sample of 754 students recruited by email and 252 people with psychosis recruited as part of a trial of cognitive therapy. We report the internal consistency, stability and the factor structure of the scale, and the association of the BCSS with measures of self-esteem and with symptoms of paranoia and grandiosity. RESULTS The BCSS have good psychometric properties and have more independence from mood than the Rosenberg Self-Esteem Schedule. People with chronic psychosis reported extreme negative evaluations of both self and others on these scales, but their levels of self-esteem and positive evaluations of self and others were similar to the student sample. CONCLUSIONS Extreme negative evaluations of self and others appear to be characteristic of the appraisals of people with chronic psychosis, and are associated with symptoms of grandiosity and paranoia in the non-clinical population. The BCSS may provide a more useful measure of schemata about self and others than traditional measures of self-esteem.

Comments on the content of persecutory delusions: does the definition need clarification?

Diagnostic criteria for subtypes of delusional beliefs based upon content have rarely been the subject of comment. In this article, several influential accounts of persecutory delusions are reviewed; differences and difficulties are noted, and their potential effect on cognitive psychological investigations discussed. One method of ensuring that researchers study similar phenomena is to use a more detailed definition than currently available, and therefore a new set of criteria is offered. Finally, related methodological problems in this emerging research area are highlighted. The issues discussed may stimulate further research on the content of delusional beliefs.

Cognitive-behavioural therapy and family intervention for relapse prevention and symptom reduction in psychosis: randomised controlled trial {

BACKGROUND Family intervention reduces relapse rates in psychosis. Cognitive-behavioural therapy (CBT) improves positive symptoms but effects on relapse rates are not established. AIMS To test the effectiveness of CBT and family intervention in reducing relapse, and in improving symptoms and functioning in patients who had recently relapsed with non-affective psychosis. METHOD A multicentre randomised controlled trial (ISRCTN83557988) with two pathways: those without carers were allocated to treatment as usual or CBT plus treatment as usual, those with carers to treatment as usual, CBT plus treatment as usual or family intervention plus treatment as usual. The CBT and family intervention were focused on relapse prevention for 20 sessions over 9 months. RESULTS A total of 301 patients and 83 carers participated. Primary outcome data were available on 96% of the total sample. The CBT and family intervention had no effects on rates of remission and relapse or on days in hospital at 12 or 24 months. For secondary outcomes, CBT showed a beneficial effect on depression at 24 months and there were no effects for family intervention. In people with carers, CBT significantly improved delusional distress and social functioning. Therapy did not change key psychological processes. CONCLUSIONS Generic CBT for psychosis is not indicated for routine relapse prevention in people recovering from a recent relapse of psychosis and should currently be reserved for those with distressing medication-unresponsive positive symptoms. Any CBT targeted at this acute population requires development. The lack of effect of family intervention on relapse may be attributable to the low overall relapse rate in those with carers.