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Jessica Macari

lusions

Delusional Misidentification SyndromesInability to register the identity of something:an object, event, place or person.

Due to malfunctioned familiarity processing during information processing

Capgras delusion

Delusional belief that a friend, family member, etc. has been replaced by a twin impostor

Most common

While they may look and act just like the real person, some essence of the person is missing, almost as though "the soul of the person isn't in there,“

( Being John Malkovich)

Visual route (visual cortex) and affective route (limbic system) face recognition

Maladaptive function of the hypersensitive amygdala: creates a feeling too strongly suspicious to be rejected

Capgras delusion

Case of Sylvie G.•Believed that her husband was transformed before her eyes into different people •Continually felt as though people she knew were replaced by other people•Sylvie looked at the shoes and feet of those she suspected were fakes, and would use that as an indicator.•She also thought her hens were replaced by older ones; she even struggled with believing her coat was the same one she’d always had.

Courbon and Tusques (French neuropsychiatrists)

Prosopagnosia

•Inability to recognize familiar faces•Cannot match the face to the person it belongs to•Individuals know the face, but elicits no emotional response.•Dysfunction in the fusiform gyrus of the brain, the part where color and facial recognition is centered

Reduplicative Paramnesia

An individual believes a place or location has been duplicated, existing in two or more places simultaneously

Reduplicative Paramnesia

• RS, a 71 year old man, no previous brain damage or history of schizophrenia• Insisted his home was not his "real" house, yet recognized his family• Noticed similarities, but still believed the house was fake• Remarked on how striking it was that the owners of this house had the same ornaments as he had in "his" house and on what a coincidence it was that there were similar items beside the bed as there were in "his" house. • At interviews, RS continued to insist that there were two "Riverside Avenues“• A few days later he believed he returned to his ‘real home’

Intermetamorphosis

When a patient confuses the identities of familiar people or feels that they are being mistaken for someone else.

Courbon and Tusques coined the term to describe the illusion where things/people suddenly change into something or

someone else.

Fregoli delusion

• A delusional belief that different people are in fact a single person (well known to the victim) who changes appearance or is in disguise• Interior of the person is different• Form of persecution

(Courbon and Fail)

The condition is named after the Italian actor Leopoldo Fregoli who was renowned for his ability to make quick

changes of appearance during his stage act. Famous for his impersonations.

History

Fregoli Case

• 35 year old woman, divorced, unemployed•Diagnosed with chronic paranoid schizophrenia, stopped medication•Suffered grandiose delusions of actors who she thought were her friends•Believed she was the girlfriend of a famous actor Erik Estrada who was always visiting her home, disguised as other people•Scored borderline impaired on the Benton Test

Mirrored-self misidentification

Belief that one's reflection in a mirror is some other person who is following them around

Patient FE• 87 year old male, married with 2 children, no history of schizophrenia• Began having nocturnal hallucinations• He started not being able to recognize himself in the mirror• He thought the mirror image was a stranger• Had knowledge about mirrors and understood what reflections were.• Later on, he was unable to recognize his wife’s reflection, said:

“I have met the stranger’s wife, seen her. I don’t think she talks, either”

Syndrome of subjective doubles

• Delusion that person has a double or doppelgänger •Same appearance, but usually with different character traits and leading a life of its own.•Sometimes the patient has the idea that there is more than one double

Reverse subjective doubles

•When one believes an impostor is taking over their body•Misidentification of the self•In the process of being replaced

Bodily Delusions

Cotard delusiona disorder where the individual believes• They are dead(either figuratively or literally)• Do not exist• Are putrefying• Have lost their blood or internal organs• Delusions of immortality• Feelings of unreality

• Named after Jules Cotard, a French neurologist who first described the condition• Mostly occurs from brain damage to the right cerebral hemisphere, which deals with the expression of visual, facial, and verbal emotion as well as body-image.• Usually accompanied by other delusions

Cotard Delusion

RB Case

• 61 year old man with a schizophrenic wife• Became depressed and overdosed, following surgery• Believed he had been dead for a week• Said he wasn’t on earth but was somewhere between heaven and hell• “Anxious agitation”• He was deeply distressed, unable to lie or sit for a long time• Electro-convulsive therapy was used, and his beliefs ceased

Somatoparaphrenia

• When an individual denies ownership of a limb, or part of their body• Sometimes believes that the limb belongs to someone else• Related to body integrity identity disorder (BIID)• May cause the person to desire amputation

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