Paranoia is one of the commonest symptoms of psychosis but has rarely been studied in a population at risk of developing psychosis. Based on existing theoretical models, including the proposed distinction between ‘poor me’ and ‘bad me’ paranoia, we aimed to test specific predictions about associations between negative cognition, metacognitive beliefs and negative emotions and paranoid ideation and the belief that persecution is deserved (deservedness).

We used data from 117 participants from the Early Detection and Intervention Evaluation for people at risk of psychosis (EDIE-2) trial of cognitive–behaviour therapy, comparing them with samples of psychiatric in-patients and healthy students from a previous study. Multi-level modelling was utilized to examine predictors of both paranoia and deservedness, with post-hoc planned comparisons conducted to test whether person-level predictor variables were associated differentially with paranoia or with deservedness.

Our sample of at-risk mental state participants was not as paranoid, but reported higher levels of ‘bad-me’ deservedness, compared with psychiatric in-patients. We found several predictors of paranoia and deservedness. Negative beliefs about self were related to deservedness but not paranoia, whereas negative beliefs about others were positively related to paranoia but negatively with deservedness. Both depression and negative metacognitive beliefs about paranoid thinking were specifically related to paranoia but not deservedness.

This study provides evidence for the role of negative cognition, metacognition and negative affect in the development of paranoid beliefs, which has implications for psychological interventions and our understanding of psychosis.

Frith et al (1995) and others have hypothesised that disruptions in the connection between left frontal and temporal areas of the brain are a central deficit in schizophrenia. In this paper we examine whether such connectivity as assessed by EEG coherence is related to level of symptoms in patients with schizophrenia.

For 73 patients with schizophrenia, assessments of the EEG coherence between frontal and temporal regions were carried out under conditions of activation by a mathematical task, and between frontal and occipital regions when performing a visuo-spatial task. We then examined the relationship between these coherence measures and the reality distortion, disorganisation and psychomotor poverty dimensions of symptomatology.

Only left frontal -temporal connectivity was found to have a significant negative relationship to symptomatology. This relationship was, however, specific to reality distortion rather than to symptoms of disorganisation or psychomotor poverty, and may be more characteristic of males than females.

Disruption of frontaltemporal connectivity appears to have a specific relationship to reality distortion symptoms in schizophrenia.

On the basis of Liddle's three-syndrome model of schizophrenia, it was predicted that: (1) symptoms of psychomotor poverty would be particularly correlated with impaired performance on neuropsychological tests likely to reflect functioning of the dorsolateral prefrontal cortex; (2) disorganisation would be particularly correlated with impaired performance on tests sensitive to medio-basal prefrontal functioning; and (3) reality distortion would be particularly correlated with measures sensitive to temporal lobe functioning.

The above hypotheses were tested on 87 subjects with a confirmed diagnosis of schizophrenia. Patients' symptoms were scored for each of the three syndromes. Patients completed six neuropsychological tests designed to measure impairment in specific areas of the brain.

There was no support for the first two hypotheses. There was, however, evidence of a specific relationship between reality distortion and neuropsychological performance usually considered to be related to left temporal lobe functioning.

Although not directly supporting the first two hypotheses; the results are, in general, consistent with there being different cortical-subcortical circuits associated with each of psychomotor poverty and disorganisation. Temporal lobe functioning appears to have particular significance for the reality distortion syndrome.