New research by Colleen Rollins (PhD Candidate) indicates that distinct anatomical signatures characterise hallucination status in patients with psychiatric and neurodegenerative diseases.

Hallucinations are experienced by many people in all the senses in both health and illness. It’s well-known that some patients with schizophrenia have predominantly auditory hallucinations, whereas patients with Parkinson’s disease more frequently have visual disturbances.

Anecdotally, the content and emotional response to hallucinations can similarly be divided by diagnosis. Many patients never experience hallucinations at all. The neuroscience of hallucinations has generally looked to theoretical explanations for unifying predictions of the brain’s underlying structural and functional components.

Our own research with patients with schizophrenia identified the paracingulate sulcus, located on the medial frontal cortex, as a key marker to their occurrence. A broader cortical signature might, therefore, signpost a generative mechanism.

In fact, our meta-analysis published in EClinicalMedicine tells us that the neuroanatomy of hallucinations in psychiatric disorders, like schizophrenia, is entirely distinct from that associated with the neurodegenerative disorders, Parkinson’s and Alzheimer’s disease.

This discovery predicts a plurality of mechanisms, creating new hypotheses for categories of hallucination that take into account the qualitative experience. Indeed, if the experience of hallucinations is closely related to specific brain structures then they may have an expanded role to play in biologically-valid diagnostic frameworks and as markers of treatment response.

Read the full here: https://doi.org/10.1016/j.eclinm.2019.01.012 

Image credit: sk172 @sk_oneseventwo