Resting-state brain networks may help explain hallucinations across different sensory modalities and populations. This report from the International Consortium on Hallucination Research reviews evidence linking resting-state alterations to auditory hallucinations, finding connectivity differences in left-hemisphere auditory and language regions, plus atypical interactions of the default mode network with networks for cognitive control and salience. Similar patterns appear in visual hallucinations, suggesting both domain-general and modality-specific network changes. However, high methodological heterogeneity across studies limits direct comparisons. The authors offer recommendations for future research on resting-state connectivity and hallucinations.
Hallucinations are often studied as isolated symptoms, but this review argues that they emerge from a broader set of changes in cognition, perception, selfhood, time, interpersonal experience, and embodiment. The authors suggest that grouping different hallucinatory experiences under a single definition may obscure meaningful differences in their causes and subjective qualities. They review phenomenological and neurocognitive theories and the role of trauma, proposing that hallucinations are an equifinal outcome of multiple genetic, neurocognitive, subjective, and social processes. Future research should incorporate a wider range of experiential alterations, and clinical practice should use phenomenologically responsive techniques and develop targeted therapies.