Multimodal hallucinations: a transcultural perspective

Abstract

This thesis explored the occurrence and phenomenology of multimodal hallucinations (MMH; i.e. perceptions without external stimulus, in multiple sensory modalities), in the context of psychosis, with a special focus on these hallucinations to jinn, voodoo or the evil eye. The results of a review of the medical literature on jinn as an explanatory model in the context of biomedical disorders are presented. Data from a multi-site Dutch GROUP study showed that MMH in western psychotic patients were surprisingly more prevalent than expected, compared to non-western patients, and the MMH lifetime prevalence was almost twice as high compared to unimodal hallucinations. A relatively large patient group reported hallucinations in 3 or 4 modalities. With these results, a hypothesis on a possible underlying mechanism in the development of MMH, a so-called stochastic process, was developed. In two subsequent chapters, the results of semi-structured interviews with both outpatient and inpatient participants showed similar patterns, providing additional indications for a stochastic process. The thesis concludes with recommendations for future research on MMH, with emphasis on understanding of the origins of MMH and subsequently, on clinical importance and alleviating distress of patients.