Questionnaire provides insight into visual hallucinations

Embargoed until: Publicly released: 2026-09-02 09:01

International

Photo by Gustavo Alejandro Espinosa Reyes on Unsplash

International researchers have developed a new questionnaire to measure the contents of visual hallucinations, such as those caused by psychedelics or strobe lights. The authors collected 962 responses to the questionnaire and found hallucinations induced by strobes were associated with simple geometric shapes, while psychedelics led to visions of real-world objects, with greater vividness and detail. By studying visual hallucinations, researchers aim to explain how the brain produces consciousness in normal and altered states.

News release

From: The Royal Society

Measuring the Contents of Hallucinations from Psychedelics and Stroboscopic Light: The Six-Dimensional Visual Hallucination Questionnaire (6D-VHQ)Royal Society Open ScienceThe brain constantly works to construct conscious visual experiences from the information it receives from the eyes. When this is disturbed, hallucinations often occur. By studying the contents of visual hallucinations, researchers aim to elucidate how the brain produces consciousness in normal and altered states. This paper presents a new tool which measures the contents of visual hallucinations: the 6-Dimensional Visual Hallucination Questionnaire (6D-VHQ). The 6D-VHQ is tested with hallucinations induced by psychedelic substances and stroboscopic light. The results demonstrate how hallucinatory experiences change across these different methods of hallucination-induction, which may reflect the distinct ways they affect the brain.

Attachments

Note: Not all attachments are visible to the general public. Research URLs will go live after the embargo ends.

Research The Royal Society, Web page The URL will go live after the embargo lifts.

Journal/
conference: Royal Society Open Science

Research:Paper

Organisation/s: University of Sussex, UK

Funder: Roxiva Innovations Ltd. provided stroboscopic light equipment for use in this research. T.H. is supported by the Margaret Boden Informatics PhD Scholarship. D.J.S. is supported by the Medical Research Council grant UKRI083. A.K.S. is supported by European Research Council Advanced Investigator grant 101019254, under the Horizon 2020 Research Programme. Additional resources were provided by the Canadian Institute for Advanced Research (CIFAR) Program on Mind, Brain and Consciousness. Conflict of interest declaration. The present study used a strobe light device provided on loan by Roxiva Innovations Ltd. Roxiva Innovations Ltd. had no role in the design, data collection, analysis, interpretation, or writing of this study. The authors are collaborators on Collective Act’s Dreamachine programme and have previously received project funding from the UK Government/Unboxed 2022 via Collective Act Ltd; this funding was independent of the current study. A.K.S. and D.J.S. have also received equipment loans from Light Attendance GmbH for unrelated projects; Light Attendance GmbH had no involvement in the present research.

Media Contact/s

Contact details are only visible to registered journalists.