Exploring the cognitive profiles related to unimodal auditory versus multisensory hallucinations in schizophrenia-spectrum disorders

ABSTRACT

Introduction

Hallucinations can be experienced across multiple sensory modalities, but psychiatric studies investigating the cognitive mechanisms of hallucinations have been somewhat restricted to the auditory domain. This study explored the cognitive profiles of individuals experiencing multisensory hallucinations (MH) in schizophrenia-spectrum disorders (SSD) and compared these to those experiencing unimodal auditory hallucinations (AH) or no hallucinations (NH).

Methods

Participants included SSD patients (n = 119) stratified by current hallucination status (NH, AH, MH) and nonclinical controls (NCs; n = 113). Group performance was compared across several cognitive domains: speed of processing, attention, working memory, verbal learning, visual learning, reasoning and problem-solving, social cognition, and inhibition.

Results

The clinical groups performed worse than NCs but differences between the clinical groups were not evident across most cognitive domains. Exploratory analyses revealed that the MH group was more impaired on the visual learning task compared to the NH (but not AH) group.

Conclusions

Preliminary results suggest that impaired visual learning may be related to MH. This could be attributed to the presence of visual hallucinations (VH), or greater psychopathology, in this group. However, replication is needed, as well as the investigation of other potential cognitive mechanisms of MH.

KEYWORDS:

• Cognition
• schizophrenia
• schizoaffective disorder
• nonauditory hallucinations
• hearing voices
• multisensory hallucinations
• auditory hallucinations

Acknowledgements

The authors would like to thank the participants for their time and efforts.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

The data that support the findings of this study are available on request from the corresponding author [MB]. The data are not publicly available because of privacy restrictions.

Additional information

Funding

WLT was supported by a National Health and Medical Research Council (NHMRC) New Investigator Project Grant (GNT1161609), and SJL was supported by a NHMRC Senior Research Fellowship [grant number GNT1154651]. TVR was supported by a Dame Kate Campbell Fellowship from the University of Melbourne.