Abstract
Visual hallucinations (VH), defined a visual perception without a corresponding object in the visual environment, are characteristic of Lewy body disorders and associated with adverse outcomes. Clinical management remains limited by reliance on retrospective self-report and challenges distinguishing between various visual experiences. We piloted a structured virtual reality (VR) environmental exposure protocol to systematically characterize abnormal visual perceptual events. Participants were exposed to four environments under varying visual conditions and narrated their experience. Narratives were independently reviewed by two clinicians for abnormal visual perceptive events. Eleven participants with Parkinson’s disease or dementia with Lewy bodies (6 VH+, 5 VH − by questionnaire) completed the protocol. Across participants, 23 abnormal perceptual events were identified (6 hallucinations, 17 misperceptions). Event phenomenology aligned with clinical descriptions and occurred more frequently during visually degraded conditions. Perceptual error events were observed more frequently in VR than typically captured through retrospective interview (2.09 vs. 0.016 per participant). However, event rates did not differ significantly between VH + and VH− groups and did not replicate participants’ typical spontaneous hallucinations. Technical and methodological constraints further limit interpretation. These findings demonstrate the feasibility and tolerability of structured VR-based assessment of perceptual vulnerability in Lewy body disorders and support further development and validation of this approach.
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Data availability
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. The code produced in house is available at https://doi.org/10.5281/zenodo.18670154.
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Acknowledgements
We wish to acknowledge Sixue Chen for technical assistance with software development and Dr. Cyrus Zabetian for access to the Washington State Parkinson’s Disease Registry.
Funding
The authors declare financial support was received for the research, authorship, and/or publication of this article. Dr. Hirczy was supported by the Veterans Affairs Advanced Fellowship Program in Parkinson’s Disease and the University of Washington Department of Neurology Catalyst Award. Dr. Kojima received funding from the Virginia Merril Bloedel Hearing Research Center.
Data Availability.
The datasets generated during and/or analyzed during the current study are available from the corresponding author on reasonable request. The code produced in house is available at https://doi.org/10.5281/zenodo.18670154.
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Contributions: CN- Conceptualization, FA – Formal Analysis, FQ- Funding, RE – Revising and Editing, RS – Resources, SU- Supervision, SW – Software, WD – Writing (Original).
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A study related patent for the automated assessment of visual hallucinations using varying virtual environments has been provisionally filed by The University of Washington with designated inventors Siegfried Hirczy and Sixue Chen (Application #63/792,128). All the other authors declare that they have no competing interests.
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Hirczy, S.S., Lin, YH., Xiong, W. et al. A pilot study of assessing visual hallucinations using virtual reality in lewy body disorders. Sci Rep (2026). https://doi.org/10.1038/s41598-026-46644-1
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DOI: https://doi.org/10.1038/s41598-026-46644-1
