Delusional misidentification syndromes (DMS) are a group of rare disorders that …
Delusional misidentification syndromes (DMS) are a group of rare disorders that leave patients convinced people and places aren’t really as they seem. Researchers at Beth Israel Deaconess Medical Center identified 17 patients with delusional misidentification syndromes and mapped them onto a standardized brain atlas. Then, using the lesion network mapping technique they recently developed, the researachers determined that the brain lesions in the patients were functionally connected to an area of the brain called the retrosplenial cortex – thought to be involved in perceiving familiarity. Read more: bit.ly/2hFnfzN
Nearly all of the lesions were also connected to a region in the right ventral frontal cortex, associated with belief evaluation. Their work, published in the journal Brain, showed that lesions causing all types of delusions were connected to belief violation regions, suggesting that these regions are involved in monitoring for delusional beliefs in general. However, only lesions causing delusional misidentifications were connected to familiarity regions, explaining the specific bizarre content – abnormal feelings of familiarity – in these delusions.
Journal article: Finding the imposter: brain connectivity of lesions causing delusional misidentifications. Brain, 2016. doi:10.1093/brain/aww288
Image credit: Rakesh Karmacharya, Wellcome Images