My Research Interests

Beach statue
I hear those voices

My research focuses on understanding the reality discrimination failures underlying hallucinations.

Hallucinations are experiences in the absence of external stimuli that are typically vivid, significant and located in external space with the qualities of real perception. They are a cardinal symptom of schizophrenia and characteristic of other psychiatric, neurological and neurodegenerative conditions including bipolar disorder, Parkinson’s disease and Alzheimer’s disease. 10-13% of the healthy population also report some life-time hallucinatory experience. Being surprisingly real, such events can challenge and frighten and thus cause high levels of disability and distress. Despite the depth and breadth of this impact, the neural systems and cognitive mechanisms involved are unresolved. Why do some people experience hallucinations and others do not? How can false experience be generated with the phenomenological properties of real perception? How do we know whether the information in our head is real or imagined?

Hallucinations in schizophrenia are associated with the morphology of the paracingulate sulcus (PCS), which lies in the medial prefrontal cortex of the brain, dorsal and parallel to the cingulate sulcus (CS). I am currently focusing on developing an understanding of the relationship between PCS morphology and hallucinations by investigating the mechanisms by which these perceptual anomalies are generated and the determinants of PCS morphological variation.

Variable paracingulate sulcus morphology.
Garrison et al. (2015). Nature Communications, 6, 8956.