Capgras syndrome is down one of the stranger avenues of neurological conditions. Its characterized by delusional beliefsthat a person often a family member, loved one, spouseor friend has been replaced by an imposter doppelgnger.
As if that couldn’t get morepeculiar,Harvard neurologists have recently published a paper in the journal Neurocase abouta man suffering from what they have coined Cat-gras Delusions. In the paper, they detail the first known case of a person whose Capgras delusions were centered on their pet cat.
Among his medical records, they found that the 71-year-old man had a history of heavy drinking, sports-related head injuries, and bipolar disorder. Six years previous to the unusualthoughts occurring, he had stopped taking his psychiatric medications and consequentlybegan suffering from delusions that the FBI was monitoring him. His thoughts then moved to his cat, believing it hadbeen replaced by an identical masqueraderwho was also involved in theconspiracyagainst him.
The study explained that he knew that the current cat resembled his pet cat physically, but that the personality or psychic core of his cat had been replaced.
Image credit:Sasha Nazim/Shutterstock
The neurologists explained that these delusional beliefs are caused by a glitch when retrieving autobiographical memory, a collection of our past experiences. Normally, when we perceive an external stimulus, our brain has to retrieve information from our internal catalogof autobiographical memories. This process allows us to associate new stimuliwith past experiences. However, in the case of Capgras delusions, the patients perception of an external object doesnt trigger the appropriate retrieval of autobiographical memory.
This can lead to them associating the external stimulus with the practical attributes, such as its appearance, but not an association with their emotional memory,leading to this lack of familiarity with aphysically recognizable object.
From information gathered throughbrain scans, the neurologists believe the erroneous thoughtpattern was linked to deterioration ofhis cerebral cortex, the region concerned with higher cognitive skills, in a process similar to dementia. This was no doubt aggravatedbythe numeroushead traumas he received whileplaying ice hockey.
Much like this case, Capgras syndromeis strongly linked to other neurological diseases and mental health issues. Its believed that 81 percent of Capgras sufferers have some form of neurodegenerative disease, most commonly Lewy body disease.
Why exactly this mans delusions were centered on his cat and not, say, his wife remains a mystery. However, while this is the first case of Cat-gras Delusions, there have been two reported cases of Capgras delusions towardsa pet dog and two cases towardspet birds.
Main image credit:Gwydion M. Williams/Flickr. (CC BY 2.0)
Read more: http://www.iflscience.com/health-and-medicine/neurological-disorder-made-man-feel-his-cat-was-imposter