This study investigated the role of reasoning biases in delusion formation and maintenance. Reasoning judgments have been shown to be influenced by prior knowledge, beliefs, and experience--that is, information stored in semantic memory. It was hypothesized that high schizotypes would exhibit a "jump to conclusions" style of reasoning as a result of not using implicit information concerned with cause-effect relationships. Research into human reasoning has traditionally adopted logic as a normative framework to assess human reasoning. Conditional inference tasks are direct tests of logical performance, and we employed an established design that depends upon the reasoner's ability to access and use implicit information. In an effort to negate some of the difficulties of research with schizophrenia patients, schizotypy measures were employed in a normal population. The results confirmed that high scorers on one dimension of schizotypy (Impulsive Nonconformity) failed to take account of the number of counterexamples that characterized the cause-effect conditional statement. These observations supported previous research demonstrating a jump to conclusions style of reasoning that it has been suggested plays a role in the formation and maintenance of delusions. Furthermore, these findings suggest a possible link between semantic memory and reasoning biases.

No abstract

Consistency with previous evidence, together with positive feedback, suggests that the PACI-O was acceptable with an offender population. Future research is required to assess the psychometric properties of the PACI-O, and to evaluate its potential as an assessment of offender motivation.

The most widely implemented offending behaviour programme in the United Kingdom was Enhanced Thinking Skills (ETS), a cognitive-behavioural group intervention that aimed to develop participant's general cognitive skills. A new offending behaviour programme has been developed to replace ETS: the Thinking Skills Programme (TSP). This study reports an evaluation of the effectiveness of TSP using psychometric assessments. Phasing of the two programmes created an opportunity to compare the two programmes consecutively. Forty participants, 20 from each programme, completed a range of psychometric measures to examine cognition, attitudes, and thinking styles. Analysis of pre- and post-programme psychometric results indicated that participants of TSP demonstrated improvements on 14 of the 15 scales, 9 of which were statistically significant. Effect sizes between pre-post results were generally greater for TSP than ETS, demonstrating that TSP had a more positive impact on the thinking styles and attitudes of participants than the ETS programme.

No abstract