Prevalence and classification of hallucinations in multiple sensory modalities in schizophrenia spectrum disorders

Abstract

We conclude that MMHs, rather than auditory hallucinations, are the most frequent perceptual symptom of patients diagnosed with a schizophrenia spectrum disorder. Our data also suggest that hallucinations experienced in a single sensory modality (notably auditory ones) stochastically increase the risk for more sensory modalities to join in. We recommend that future studies take into account all 14 sensory modalities in which hallucinations can be experienced. For this we provide a classification of MMHs that allows characterization of their serial versus simultaneous occurrence and their congruent versus incongruent nature.