Delusions demand attention

Transdiagnostic neural markers of emotion-cognition interaction in psychotic disorders

Deficits in working memory (WM) and emotion processing are prominent impairments in psychotic disorders, and have been linked to reduced quality of life and real-world functioning. Translation of knowledge regarding the neural circuitry implementing these deficits into improved diagnosis and targeted treatments has been slow, possibly because of categorical definitions of disorders. Using the dimensional Research Domain Criteria (RDoC) framework, we investigated the clinical and practical utility of transdiagnostic behavioral and neural measures of emotion-related WM disruption across psychotic disorders. Behavioral and functional MRI data were recorded while 53 participants with psychotic disorders and 29 participants with no history of psychosis performed a modified n-back task with fear and neutral distractors. Hierarchical regression analyses showed that psychotic symptoms entered after diagnosis accounted for unique variance in fear versus neutral accuracy and activation in the ventrolateral, dorsolateral, and dorsomedial prefrontal cortex, but diagnostic group entered after psychotic symptoms did not. These results remained even after controlling for negative symptoms, disorganized symptoms, and dysphoria. Finally, worse accuracy and greater prefrontal activity were associated with poorer social functioning and unemployment across diagnostic groups. Present results support the transdiagnostic nature of behavioral and neuroimaging measures of emotion-related WM disruption as they relate to psychotic symptoms, irrespective of diagnosis. They also provide support for the practical utility of these markers in explaining real-world functioning. Overall, these results elucidate key aspects of the RDoC construct of WM maintenance by clarifying its transdiagnostic importance and clinical utility in psychotic disorders. (PsycINFO Database Record

Using theories of delusion formation to explain abnormal beliefs in Body Dysmorphic Disorder (BDD)

Body Dysmorphic Disorder (BDD) is characterised by overvalued or delusional beliefs of 'imagined ugliness'. Delusional beliefs have been explained by a number of cognitive theories, including faulty perceptions, biases in attention, and corruption of semantic memory. Atypical aesthetics may also influence beliefs in BDD. In fourteen BDD patients, compared to controls (n=14), we examined these theories of beliefs in a cognitive test battery consisting of perceptual organisation and visual affect perception tasks, a Stroop task using body words, a sentence verification task, a fluency task, and an attractiveness task. BDD patients performed similar to controls on tasks measuring information (bias) processing and aesthetics. However, BDD showed abnormal abilities on semantic processing involving sentence verification and category fluency. There was only a trend finding of impaired performance on perceptual processing tasks in BDD. The findings suggest that the delusional beliefs in BDD may be explained by impaired semantic processing.

Paranoid thinking, suspicion, and risk for aggression: a neurodevelopmental perspective

This article represents an effort to extend our understanding of paranoia or suspicion and its development by integrating findings across clinical, developmental, and neuroscience literatures. We first define "paranoia" or paranoid thought and examine its prevalence across typically and atypically developing individuals and theoretical perspectives regarding its development and maintenance. We then briefly summarize current ideas regarding the neural correlates of adaptive, appropriately trusting interpersonal perception, social cognition, and behavior across development. Our focus shifts subsequently to examining in normative and atypical developmental contexts the neural correlates of several component cognitive processes thought to contribute to paranoid thinking: (a) attention bias for threat, (b) jumping to conclusions biases, and (c) hostile intent attribution biases. Where possible, we also present data regarding independent links between these cognitive processes and aggressive behavior. By examining data regarding the behavioral and neural correlates of varied cognitive processes that are likely components of a paranoid thinking style, we hope to advance both theoretical and empirical research in this domain.

Selective attention to threat bias in delusion-prone individuals

The study examined the selective attention to threat bias in delusion-prone individuals recruited from New Religious Movements (NRMs). Twenty-seven delusion-prone NRM individuals were compared with 25 individuals with psychotic disorders and 63 non-delusion-prone individuals on a Stroop task, together with psychotic and delusion proneness measures. NRM individuals showed significantly lower levels of selective attention to threat bias compared with individuals with psychotic disorders but not with non-delusion-prone individuals. Selective attention to threat bias was also not correlated with distress associated with delusional ideation. These findings may be specific to delusion-prone NRM individuals. The absence of the selective attention to threat bias may be related to levels of safety and security among members of NRMs.

Specificity of emotion-related effects on attentional processing in schizotypy

OBJECTIVES

In the schizophrenia spectrum, cognitive functions such as perception, language, and attention have been shown to be adversely influenced by negative affect. The present study addressed three issues of specificity and one issue of mechanism regarding affect-related attentional disruption in schizotypy: (1) Is attentional disturbance from negative affective stimuli specific to positive (PS) but not negative schizotypy (NS)? (2) Do positive affective stimuli also foster attentional disturbance? (3) Are anxiety and depression differentially related to PS and NS? (4) Whatever the degree of specificity in these relationships, does anxiety mediate the relationship between schizotypy and attentional disturbance?

METHODS

Nonpatient participants (N=162) provided responses on scales of schizotypy, anxiety, and depression and performed an emotional Stroop task, judging the ink color of positive, neutral, and negative words.

RESULTS

PS but not NS was associated with poorer attentional performance. This attentional disturbance was specific to negative words. PS was associated with anxiety and depression, whereas NS was associated only with depression. Finally, anxiety and depression did not fully mediate the relationship between PS and attentional interference related to negative affective stimuli.

CONCLUSIONS

Findings of attentional disturbance in the presence of negative affective stimuli, particularly in positive schizotypy, have substantial theoretical implications. They provide a path by which the interplay of cognitive and affective phenomena could lead to the formation, maintenance, and exacerbation of positive symptoms, including delusions and hallucinations. Findings from this study also underscore the importance of examining the differential contribution of comorbid anxiety and depression to cognitive and affective function in the schizophrenia spectrum.

Cognitive neuropsychiatry and delusional belief

Cognitive neuropsychiatry is a new field of cognitive psychology which seeks to learn more about the normal operation of high-level aspects of cognition such as belief formation, reasoning, decision making, theory of mind, and pragmatics by studying people in whom such processes are abnormal. So far, the high-level cognitive process most widely studied in cognitive neuropsychiatry has been belief formation, investigated by examining people with delusional beliefs. This paper describes some of the forms of delusional belief that have been examined from this perspective and offers a general two-deficit cognitive-neuropsychiatric account of delusional belief.

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.

Persecutory delusions: a review and theoretical integration

Persecutory (paranoid) delusions are a frequently observed clinical phenomenon. In recent years, an increasing volume of research has attempted to explain these types of beliefs in terms of psychological mechanisms. Theories have emphasized early experience, perceptual abnormalities, motivational factors, and information-processing deficits. In this article we review relevant findings, including our own studies of the role of causal attributions and theory of mind deficits. We propose a new integrative model that builds on this work. The core of the model is an account of the way that causal attributions influence self-representations, which in turn influence future attributions: the attribution--self-representation cycle. We argue that biases in this cycle cause negative events to be attributed to external agents and hence contribute to the building of a paranoid world view. These abnormalities are amenable to investigation by functional neuroimaging, and recent studies have implicated specific areas of neuroactivation. However, these findings do not necessarily suggest that paranoid delusions are entirely biological in origin, and there is evidence that adverse early experience may play a role in determining the development of a cognitive vulnerability to paranoid thinking.

Cognitive neuropsychiatry: towards a scientific psychopathology

Cognitive neuropsychiatry represents a systematic and theoretically driven approach to explain clinical psychopathologies in terms of deficits to normal cognitive mechanisms. A concern with the neural substrates of impaired cognitive mechanisms links cognitive neuropsychiatry to the basic neurosciences. The emergence of cognitive neuropsychiatry in the 1990s illustrates the growing rapprochement between cognitive neuropsychology, clinical medicine and the neurosciences in addressing common questions about disorders of the mind/brain. In reviewing recent applications, we highlight how this hybrid discipline will make a distinctive contribution to the science of psychopathology.