I admit that both my wife and I love to watch some of the medical thrillers and police procedural shows on television. We record them and, when time permits, we take a break from life and immerse ourselves into the world of make-believe.

It’s interesting that I describe these shows as “the world of make-believe” because the best fiction plots these days usually are based on facts.

An especially interesting new show this season is called Black Box. Its central theme involves the practice of neuroscience, which I’ve blogged about often in the past (Here, Here and Here).

A particular episode fascinated me because one of the patients Dr. Black treated was convinced that he was dead—he was certain that he had died and transitioned to a “walking dead” state. Since researching this subject, I’ve discovered that other TV programs have used this mental illness as a plot premise, as in one of the more popular episodes of Scrubs.

In 1880, the neurologist Jules Cotard described this mental disorder as “The Delirium of Negation” and the disease has since been alternately named Cotard’s Syndrome, Cotard Delusion and Walking Dead Syndrome.

The simple definition of Cotard’s Syndrome is that a person thinks that he or she is already dead but still maintains the capacity to move around. The patient walks aimlessly with no purpose and with no interest in sleep, so the person feels trapped in a zombie-like state of existence.

People afflicted with this mental disease have a strong delusion that either they have already died, do not exist or that their blood and/or internal organs have been lost. Some of the patients with this mental disease also believe that they have lost various body parts or insist that they have lost their soul.

With this disorder, people have trouble performing simple personal hygiene tasks such as bathing or brushing their teeth. They are unable to conduct day-to-day work activities or perform any kinds of actions that normal people do. They withdraw from the world, thinking that their bodies are decaying and putrefying, and their minds even delude them into seeing the process of decay when they look at their reflection in a mirror. They often do not eat, drink, speak much or interact with others.

Patients with Cotard’s Syndrome have been shown to spend considerable time in a graveyard because that is where they believe they should be.

There were over 1,000 cases documented in 2013. And, although Cotard’s Syndrome was not included in the 1994 nor the 2000 edition of the Diagnostic and Statistical Manual of Mental Disorders, it was included in the tenth edition of the International Statistical Classification of Diseases and Related Health Problems of the World Health Organization, in which “Cotard Delusion” is identified as a disease of human health.

Cases have been reported in patients with mood and psychotic disorders, and the psychiatric syndrome has varying degrees of severity. Mild cases exhibit as despair and self-loathing, and more severe cases are characterized by intense delusions of non-existence and chronic psychiatric depression.

A recent study of a Cotard’s patient showed that the PET scan of the person’s brain indicated low metabolic activity. Additionally, large parts of the patient’s frontal lobe (which controls attention, memory and motivation) and the parietal lobe (sensory perception) of this patient’s brain had almost no activity—a condition common to people in the vegetative state.

The cause of Cotard’s Syndrome is still unknown, but one famous case was the vocalist in a black metal band called Mayhem and the vocalist developed Cotard’s after he was resuscitated following a serious auto accident.

What is known is that most cases of Cotard’s are more responsive to electroconvulsive treatment (ECT) than to pharmacological therapies. Follow-up psychotherapy with antidepressants, antipsychotics and/or mood stabilizers has proven to be beneficial, however, in restoring a positive self-image for these patients as well as a more normal hopefulness about their future.

So, if you’re looking for a zombie-like plot scenario but want a more scientifically-based rather than science fiction-based approach, than look into Cotard’s Syndrome for a reasonable explanation of your next walking corpse character.

Thoughts? Comments? I’d love to hear them!