Psychiatrists Report Rare Case of Woman Who Thinks She’s a Chicken 

Sabine Verschelde 

July 31, 2020

LEUVEN, Belgium—A 54-year-old woman has suffered the delusion of thinking she is a chicken for 24 hours. This very rare condition, known as zoanthropy, in which people think they are an animal is often not recognised, say researchers from the University of Leuven.

Zoanthropy can include people believing they are, or behaving like, any kind of animal: from a dog, to a lion or tiger, crocodile, snake, or bee.

It’s important to recognise this as a potential symptom of something serious, say the researchers in the July issue of the Belgian Journal of Psychiatry, Tijdschrift voor Psychiatrie.

The delusion can be a sign of an underlying psychiatric disorder, or it can be secondary to structural or functional abnormalities in the brain.

"Additional investigations with brain imaging and electroencephalogram are therefore advised,” say the authors. 

Psychiatrists Need to Be Aware That Clinical Zoanthropy Exists

In their paper, they describe the case of the woman who briefly thought she was a chicken, which was followed by her having a generalised epileptic seizure.

"Clinically, we saw a lady who perspired profusely, trembled, blew up her cheeks, and…seemed to imitate a chicken, [making noises] like clucking, cackling, and crowing like a rooster," they say.

"After about 10 minutes she seemed to tighten her muscles for a few seconds, her face turned red and for a short time she didn't react. These symptoms repeated themselves at intervals of a few minutes [and her] consciousness was fluctuating," with the patient "disoriented in time and space".

Lead author Dr Athena Beckers of University Psychiatric Centre, KU Leuven, Belgium, said in an interview with MediQuality: "With only 56 case descriptions in the medical literature from 1850 to the present day, the condition is rare. It amounts to about one description every 3 years.

"We suspect, however, that the delusion is not always noticed: the patient shows bizarre behaviour or makes animal sounds, it is probably often catalogued under the general term 'psychosis'."

Dr Beckers adds that it is important that the symptoms are recognised, because of the possible underlying causes which can include epilepsy. So this might require a different or complementary treatment "with, for example, antiepileptic drugs".

"I myself have only seen this type of delusion once, but I…heard anecdotal stories from other patients whose family member, for example with schizophrenia, sometimes thought he was a cow [during]…a psychosis.

"After the publication of my article I was also contacted by someone who told me they had experienced the same thing 30 years ago - he thought he was a chicken.

"I think it's a good thing that we psychiatrists are aware of the fact that clinical zoanthropy exists and may require additional research," she observed.

Fortunately, this woman's experience ended well. After about one year of disability, the patient was able to return to work progressively. Her mood remained stable and there were no more psychotic symptoms or any indication of epileptic episodes.

Such Delusions Are Rare 

Dr Georges Otte, a recently retired neuropsychiatrist who formerly worked at Ghent University, Belgium, gave his thoughts to Mediquality: "The interface between neurology and psychiatry…is a fertile meadow on which many crops thrive. But it is in the darkest corners of psychosis that one finds the most bizarre and also rarest excesses."

There are a number of delusions of identity, said Dr Otte.

These include Cotard’s syndrome, a rare condition marked by the false belief that the person or their body parts are dead, dying, or don’t exist, or Capgras delusion, where the affected person believes that a spouse or close family member has been replaced with an imposter. Delusions can also occur as a result of substance abuse, for example after using psilocybin (magic mushrooms), he added.

"Delusions in which patients are convinced of ‘shape shifting’ (man to animal) are quite rare," Dr Otte observed.

"In the literature we know that lycanthropy [a person thinks they are turning into a werewolf]," has been reported, and has "apparently inspired many authors of horror stories," he added.

"But it’s not every day that as a psychiatrist, you will encounter such an extreme psychotic depersonalisation as someone turning into a chicken."

Tijdschr Psychiatr 2020;62(7):582-586. Abstract.

Translated and adapted from MediQuality, part of the Medscape Professional Network.


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