An investigation of a novel transdiagnostic model of delusions in a group with positive schizotypal symptoms

Abstract

Introduction

Although several theories of delusions have been put forward, most do not offer a comprehensive diagnosis-independent explanation of delusion aetiology. This study used a non-clinical sample to provide empirical support for a novel transdiagnostic model of delusions that implicates aberrant semantic memory and emotion perception processes as key factors in delusion formation and maintenance. It was hypothesised that among a non-clinical sample, people high in schizotypy would demonstrate differences in semantic memory and emotion perception, relative to people low in schizotypy.

Methods

Using the Cognitive Disorganisation subscale of the Oxford-Liverpool Inventory of Feelings and Experiences, 41 healthy participants were separated into high and low schizotypy groups and completed facial emotion perception and semantic priming tasks.

Results

As expected, participants in the high schizotypy group demonstrated different performance on the semantic priming task and reduced facial affect accuracy for the emotion anger, and reaction time differences to fearful faces.

Conclusion

These findings suggest that such processes may be involved in the development of the sorts of unusual beliefs which underlie delusions. Investigation of how emotion perception and semantic memory may interrelate in the aetiology of delusions would be of value in furthering our understanding of their role in delusion formation.

Keywords:

• delusions
• semantic memory
• schizophrenia
• schizotypy

Notes

1. In reality, the participants scoring lowest and highest on the Cognitive Disorganisation scale were the same participants scoring lowest and highest on the Unusual Experiences scale.

2. As frequency did not interact with group or any of the other variables in the ANOVA no further comment will be made about this task manipulation.

Additional information

Funding

Funding: This paper was undertaken as part of an unfunded project at the University of Melbourne for the fulfilment of a DPsyC awarded to CC.