Belief flexibility and trustworthiness in adults experiencing paranoia

Previous research has found associations between belief flexibility and delusional severity in clinical and non-clinical samples, but little is known about paranoia and belief flexibility. Additionally, studies have found people with paranoia make lower trustworthiness judgments compared to healthy controls, however, the research lacks relevance to day-to-day life.
Section one of this thesis aimed to review the current literature and develop an understanding of the relationship between belief flexibility and paranoia. Moreover, the review hoped to gain insight into whether there was a difference in belief flexibility in individuals experiencing low and high paranoia. A systematic literature search identified eight studies to be included in the current review. Of the eight studies, six studies examined non-clinical samples whilst two studies assessed clinical samples with non-clinical samples recruited as controls. Despite efforts to identify studies investigating differences in belief flexibility between low and high paranoia groups, only three studies were found. The review yielded mixed findings on the relationship between belief flexibility and paranoia in non-clinical and clinical samples, with some evidence suggesting that reduced belief flexibility predicted paranoia. However, of the three studies examining the difference in belief flexibility between the two groups, only one study reported on the association, which was found to be non-significant. The current review was the first to examine the relationship between belief flexibility and paranoia. However, due to the methodological limitations of the included studies, the findings from this review should be interpreted with caution. Further studies are required to aid the understanding of belief flexibility in people experiencing paranoia.
The second section of the thesis focused on the empirical study. The current study aimed to identify whether there was a difference in the rate a person experiencing low or high paranoia adjusts their trust judgements after receiving new information. Participants completed an online scenarios-based task measuring trust judgements in trustworthy and untrustworthy conditions. Questionnaires related to paranoia, attachment, self-esteem, analytical thinking, and belief updating were also completed. The study examined changes in trustworthiness judgements when the characters in the task behaved consistently, for example, always trustworthy or untrustworthy, and following a trust violation when the characters suddenly behaved in an opposite fashion to their previous behaviour. Trustworthiness judgements in both conditions between the low and high paranoia group were non-significant when the characters behaved consistently and following a trust violation. However, participants changed their trust judgements in response to additional information in the way that was expected, suggesting the task in the current study is sensitive to measures of trust judgements. In both conditions, a significant interaction between gender and time, with greater trustworthiness rating for females across time, and a significant interaction between age and group, with greater paranoia severity demonstrated in younger people, was found. However, the association between high paranoia and attachment insecurity and self-esteem was non-significant. The strengths and limitations of the study, implications of the findings, and recommendations for future research are addressed in the study.