This terrifying disorder turns people into zombies, into living, breathing ghosts; they believe they died, or never existed. And somewhere in their brains may be the key to human consciousness.

By Erika Hayasaki
Photographs by Eunice Adorno for Matter
Conceptual photographs by Marlous van der Sloot


I’ve come to Mexico City to find the real walking dead.

Glancing around the courtyard of the walled-off National Institute of Neurology and Neurosurgery, you might think this place is filled with them. Two dozen patients chew and pick at their lunches of yellow chicken legs and bread rolls, while others slump listlessly around a courtyard. Some are catatonic. Blank. Others are simply bodies in beds, slumbering beneath the sheets, unconscious in the afternoon. One woman with flared nostrils presses a bony shoulder into her mattress, cradling her emaciated body.

Most of the patients here have been diagnosed with garden-variety neurological disorders: schizophrenia, dementia, psychosis, severe depression, or bipolarism. But the ones I am searching for are different. They suffer from an affliction even more puzzling: They believe that they are dead.

It’s a rare disorder called Cotard’s syndrome, which few understand. For patients who have it, their hearts beat and lungs pump, yet they deny their existence or functionality of their bodies, organs or brains. They think their self is detached.

Gazing around the compound, I lock eyes with a 52-year-old woman in cotton pajamas who’s curled into a half-fetal position in a pleather blue chair. She looks rabid, and for a moment it seems like she wants to lunge at her doctor — or raise a fist at me. Her short tendrils of hair are matted. Her teeth, rotting. She wears blue sandals that look like Crocs, and through the gaps I notice her toenails are gnarled. Her name is Juanita and she has told doctors, from time to time, that she does not exist.

Something intangible separates her. Is she one of them? Or is she one of us?

Since it was first documented in 1880, more than a hundred cases of Cotard’s have been reported all over the world. There’s the 59-year-old woman who was hospitalized in the United Kingdom after reporting feeling like she was “a rotting corpse.” She told doctors the blood circulation to her legs was damaged, and her legs were falling off. Then there’s the 62-year-old Spanish man who was convinced not only that he was dead, but also that his penis was disappearing. A middle-aged Japanese woman complained that her mind was “completely blank with no thoughts,” that there seemed to be no brain in her head, and she could not talk because she’d “lost all her words.”

There is an inherent insensitivity in likening Cotard’s patients to the fictional living dead, as the Internet tends to do. But we have the crude tendency to compare people with Alzheimer’s and other dementias to zombies. Neuroscientists have even drawn similar conclusions: “If ever there were a syndrome that might explain what it feels like to be a zombie, Cotard’s delusion is it,” write Timothy Verstynen and Bradley Voytek, in Do Zombies Dream of Undead Sheep: A Neuroscientific View of the Zombie Brain.

We are captivated by shows like The Walking Dead, which feature the bloodthirsty with hair matted, teeth rotten, nails gnarled. Heads cocked to the side while doing that unmistakable wobble-walk. In our suspension of disbelief, they once were us. Now, they are primal. Intelligence deducted. They look like a grimier version of themselves, even though they no longer are themselves.

Cotard’s patients are seemingly caught in this strange life-death paradox. They believe they know what death feels like. I’ve spent the last half-decade researching and writing on mortality issues, hanging out at death conferences and even enrolling in a college class on death. From simulating near-death experiences to studying the memories of cardiac arrest patients whose hearts stopped beating until they were resuscitated, I’ve often thought about how we challenge the EEG lines that separate death and life because we’re scared of dying. How we live in denial of the finality.

After a neurologist at UCLA told me about Cotard’s patients he studied at the Mexico institute, I boarded a plane from Los Angeles. Turning my 8-month-old over to my husband, I left the cradle of life to explore the ledge of death.

Crumpled in the blue easy chair, Juanita heaves. She is glassy-eyed and skittish. The doctor gently holds her right hand.

Juanita, whose name has been changed to protect her privacy, was admitted to the ward at age 46 and diagnosed with Cotard’s after suffering from a stroke in her temporal lobe, which led to a lesion in her brain. She complained that her limbs had vanished, that her body was defunct and empty like a dummy. She lost the desire to work, eat, live. At times, she was free of the delusion; she recognized her body and her organs, but for much of her waking moments, she was convinced that she was not alive. Now, six years later, this is her 18th visit to the Institute.

Doctors know little about the neurological causes of Cotard’s. Some believe it is not in fact a singular disease, but rather an impermanent condition that is often associated with some combination of encephalitis, Parkinson’s, brain tumors, schizophrenia, depression, bipolar disorder, hypothermia, or brain injuries. Because it’s so atypical, many neurologists and psychologists around the world don’t even think to identify it, or know how.

But the head of this neuropsychiatry unit, Dr. Jesús Ramírez-Bermúdez, might be closer than anyone in figuring out its neurological roots. He has documented and treated more Cotard’s cases at this institute than any other specialist worldwide — a total of 12 — since encountering his first in 2000. To him, studying patients like Juanita is not just about treating them. It’s about trying to understand what is happening in their brains in those moments when they believe they do not exist. “That some people can really experience death in their minds in a delusional way — in a very intense suffering way — has universal value,” he tells me.

Dr. Jesús Ramírez-Bermúdez

What is death, after all, but the dissolution of the self? Beyond the physical feeling of death, if Cotard’s patients have indeed lost their sense of self, understanding why could offer some answers to the most elusive mysteries facing neuroscientists and philosophers: Where does consciousness come from, and how is the self generated?

Juanita is drooling now. She is aware of Dr. Ramírez-Bermúdez, and of me, I think.

“Que paso?” the doctor asks her.

She begins to weep, her chapped, red-rutted face turning a brighter shade, as she trembles.

“Que paso?” he says again.

In an instant, her eyes fill with fury. She looks rabid. Twisting in her seat, she screams in Spanish: “I just want to get the fuck out of here!

Later, in his office, after leaving Juanita to calm down in her room, Ramírez-Bermúdez sketches a diagram of her brain on a sheet of paper, shading her damaged areas, and pointing out the corresponding areas on the computer, where he has pulled up her neurological scans.

Juanita is one of the most difficult Cotard’s cases he has encountered. She not only suffers from a brain lesion, but has also lived much of her life in a destructive home environment. “My son hates me,” Juanita said during her consultation with Ramírez-Bermúdez. She hits her brother sometimes, and he hits her. “I hate that fucking dog,” she says of him. It’s hard to know how much her home life has contributed to her Cotard’s.

Dr. Jesús Ramírez-Bermúdez draws a picture of the brain.

Ramírez-Bermúdez points to a section of Juanita’s brain on the scan: There is a dark mass on the left side where her lesion lies, affecting the amygdala, which works in concert with the temporal lobes — areas involved in self-awareness, consciousness, and feelings. “Positive emotions produced by the left hemisphere are gone. She cannot produce them, or she has very few,” he says. “Ninety percent of the time she is sad, or angry, or anxious, or fearful.”

Despite Juanita’s erratic behavior, she doesn’t think she’s dead at the moment. For the past three years she has been taking the antipsychotic medication clozapine, which has alleviated her Cotard’s symptoms. But even when Juanita is experiencing a full-blown Cotard’s episode, she still feels emotions. And the most powerful among them might be one of the most human of all: misery.

“They exist in a state of frequent despair,” Ramírez-Bermúdez says of Cotard’s patients. “That’s why they frequently try to commit suicide.”

It’s a maddening quandary to believe you are dead — to know you do not belong on this earth, yet remain here, utterly sad, hopelessly lingering around. Somewhere in the patients’ minds they must realize, if even fleetingly, that they are not actually in-the-ground dead. When they do, Ramírez-Bermúdez explains, it drives some to try to get there. Self-starvation. A blade to the neck. Jumping off a rooftop.

“As a desperate attempt to restore the ability to feel something — anything! — such patients may try to inflict pain on themselves in order to feel more anchored in their bodies,” writes Dr. VS Ramachandran, a neuroscientist at UC San Diego, of Cotard’s patients. If depression had a worst-case scenario, some might consider Cotard’s to be its most dire distant cousin. For many patients, what begins as a state of anxiety, paranoia, fear, like in Juanita’s case, later turns into despondency.

Juanita has an elderly mother, who visits her in the neurology ward often. She is the only stable family presence in Juanita’s life. During each visit, the frail woman sits by her daughter’s side, looking for hints of the person she once was, hoping she will get better.

After spending time with Juanita, I begin to realize that Cotard’s patients are nothing like zombies. Cotard’s patients may have delusions of decay one day and with treatment be rid of them the next. The fact that they can feel at all means they’re trapped in their own living hell.

Patient Rafael Hernández holds his wife, Gisela’s, hand.

Seventy-six-year-old Rafael Hernández hovers at the edge of his dining room, away from his distraught wife, Gisela, who repeatedly wrings her hands and rests them on the plaid tablecloth as she tells me about her husband’s precarious mental state. Rafael has recently been diagnosed with psychotic depression and Cotard’s.

“It is very, very difficult,” she begins. “Not understanding what’s going on. Jesus, when he was crucified, had to walk and he fell. It’s the same process. Falling, standing up. It’s been a long learning process.”

Rafael’s khaki pants and brown cardigan hang off his body. He is hunchbacked, and his mouth sags in a permanent pout. He has not smiled for years. “I’m very afraid. I want to run away now,” he mumbles. “Something is not right, and it’s more than you can imagine.”

We’re sitting inside the couple’s vibrant Mexico City home, which is adorned with collections of intricately painted vases and chinaware, lush plants, and yellow walls. But it’s clear to me that Rafael does not fit in here anymore.

Rafael Hernández

Gisela switches from exasperation to tears, recounting her husband’s cognitive decline. Rafael was once a very different man. Gisela began dating Rafael when she was 15. He loved to debate and was passionate about politics. He always wanted to have the last word. Rafael received a master’s degree in chemical engineering and a doctorate in economics. But 10 years ago, he began to lose interest in his passions. He was no longer active, preferring instead to stay home when she traveled. Last October, Rafael began to speak of feeling like he was not in this world. He complained that his kidneys and organs were obsolete.

“Does your stomach hurt?” Gisela would ask.

He would reply that he did not have a stomach.

“There might be a problem with it,” she said, “but you do have a stomach.”

As Rafael’s illogical behavior continued, he told her he felt spirits all around, and he said things to her like “You are not you. You are a ghost.”

On the Day of the Dead, Mexico’s holiday celebrating loved ones who have passed away, he questioned why his picture was not on the table along with the shrine commemorating the dead. He believed he should have received offerings of food and tequila.

Eventually, he spoke of suicide. After losing 44 pounds in a matter of months, Rafael was hospitalized and put on feeding tubes.

Rafael, his wife, and their daughter.

Rafael listens with his head hanging as his wife speaks about his plight. Gisela takes his hand. Rafael squeezes her hand back. Under the institute’s care, Rafael received electroconvulsive therapy treatments for one month. Such treatments have shown to improve or eliminate symptoms, sometimes curing patients all together.

Rafael improved significantly, Gisela says. But she’s worried that he’s beginning to deteriorate again. Lately, he complains that his teeth do not work, which is why he believes he cannot properly chew or digest food. His doctors say his teeth are fine. He’s having a Cotard’s delusion.

I ask Rafael if he can describe what it’s like to feel dead, and he replies faintly in English: “All my past, all my experience, all my interests, my doctorate degree, my Ph.D. in economics. Now, I am without capacity to remember.”

As with other cases, Rafael’s Cotard’s began with depression, though it would be jumping to conclusions to say that depression is the cause. “Most patients who are severely depressed don’t go around claiming they are dead,” says Dr. Ramachandran. “Something else must be going on.”

Cotard’s syndrome is not listed in the Diagnostic and Statistical Manual of Mental Disorders. The only real way to diagnose it is to conduct psychiatric interviews that must rule out other similar disorders like asomatognosia, a neurological condition that leads to the feeling that one’s body parts are missing.

Ramírez-Bermúdez relies on questioning drawn from the medical literature to diagnose cases, and has determined which specific questions and answers to pay attention to:

“How long have you been a patient?”

Forever. I have always been here. (Indicating, in the Cotard’s patient, that time has stopped flowing, or is moving impossibly slow.)

“Do you know who I am?”

You are no one. You do not exist.

“Who are you?”

I am nothing.

I can’t help wondering: If one doctor reads certain behaviors as delusional depression, psychosis, asomatognosia, or something else, could another call it Cotard’s?

Dr. Ramírez-Bermúdez looks at scans of Juanita’s brain.

Ramírez-Bermúdez has his theories about the roots of Cotard’s. Studying Juanita’s behavior over the years, he found that she scored poorly when asked to identify some colors, animals, fruits, and vegetables. Like patients suffering from semantic dementia, Juanita couldn’t make the right connections. She had trouble on another test, too, one that required explaining or understanding the definition of words like bottle or bowl.

Perhaps a similar network of neural disconnections explains why a Cotard’s patient might not recognize an organ as an organ, or life as a life. Juanita’s brain lesion extends into the anterior temporal lobe — the area that is involved in linking perceptions with actions — which has led to some loss of that semantic memory. Could the delusion of death and problems in semantic processing simply be a rare coincidence? Or could the two conditions be related? Ramírez-Bermúdez wanted to find out.

Two years after encountering Juanita, Ramírez-Bermúdez met a woman who could help solve the puzzle. “Mrs. A,” the 56-year-old patient, had both Cotard’s and semantic dementia, could no longer grasp the word laundry, and could not name items like a pen, shoes, or glasses, or body parts like chin, hair, nose, or knee. Ramírez-Bermúdez, along with UCLA neurologist Mario Mendez, studied the woman, noting that she had been a vegetarian, but could no longer understand the word vegetarian either. She lost the concept of vegetarianism, too, and even began to eat meat.

In tests, Mrs. A also could not recognize any of the 24 famous faces shown to her, although she could recognize her own face in the mirror. She complained about pains throughout her body but could not describe the specific organs to address where her pains were located. “I am dying from the inside,” she said.

When Ramírez-Bermúdez and his colleagues took MRIs of Mrs. A’s brain, the scans showed atrophy in the temporal lobe regions on the left side of her brain, those responsible for understanding language and interpreting sensory images — the same areas affected by Juanita’s lesion.

Semantic networks of the brain allow us to assign purpose to the world’s concrete parts. You know what role a laptop computer fulfills for you. You know what tapping each key will do, how to press the right button to send an email, search on Google, or socialize. Without the semantic neural networks making those connections, the computer would appear before you as a useless heap of fragments. The world would lose meaning.

The doctors proposed that a person’s loss of semantic knowledge about her body — how it works, how it functions in the world — may, in some cases, lead to delusions of death. But how could not knowing the purpose of your own liver or heart lead you to deny your own existence altogether?

Dr. Ramírez-Bermúdez with other doctors at the National Institute of Neurology and Neurosurgery.

You might think of living as a simple equation: Perception of object + emotion = meaning. Without either, there is nothing.

While semantic networks give purpose to the concrete parts of the world — a computer or a bowl — the limbic networks (essential in memory, intention, and behavior) provide the understanding of why you are typing. I want to write a note expressing to this person how angry I am. Or why you are sipping. It’s cold outside and I desire something warm and steamy.

What if Cotard’s affects both the semantic and limbic systems? Last year, Ramírez-Bermúdez encountered a 50-year-old Cotard’s patient, brought into the institute by her family after a suicide attempt. She claimed to hear the voice of God, who told her that her children were going to die, and their bones, flesh, and blood would be taken out of them.

This patient reminded Ramírez-Bermúdez of a theory presented by Dr. Ramachandran, which considered whether Cotard’s bore similarities to another rare condition: Capgras delusion, a condition in which the facial-recognition area of the brain is disconnected from the amygdala in the limbic system, so a person is unable to recognize someone he or she has known or loved.

Ramachandran measured the emotions of a 30-year-old Capgras patient who had been in a coma after a traffic accident and woke up referring to his father as an impostor. Ramachandran analyzed the patient’s reactions to potential stimuli. The patient did not respond any more viscerally to photos of his parents than to photos of strangers, proving that he had no familiar feeling of warmth, or protection, or love when he saw them.

Cotard’s patients, Ramachandran predicted, could have complete loss of emotional reactions, not just with faces, but with provocative images of sex or violence. An overall deadening of the senses. He theorized that for patients with delusions of death, all sensory recognition areas are detached from the limbic system. So Ramírez-Bermúdez tested the theory with his Cotard’s patient, assessing her physiological and psychological arousal by attaching electrodes to her skin to measure her galvanic skin responses. Her reactions? Faint blips on the emotional scale.

It seemed, based on Ramírez-Bermúdez’s tests of his suicidal Cotard’s patient, that Ramachandran’s hypothesis could be right. Her sensory switches seemed to be shut off in response to certain stimuli. Her limbic system, largely unresponsive. When it came to emotional reactions, she was numb. Detached from her own self — the parts of her body and its place in the world, as well as the emotional meaning of these parts.

Why, how, or where exactly these connections may have been severed remains as unexplainable as why a person who feels almost no emotion, or feels dead, might want to kill herself. Ramírez-Bermúdez says this evidence indicates that Cotard’s and other psychiatric disorders “arise from a complex interplay” between these various bodily parts, which suggests that the seat of the self is not one particular region of the brain.

It’s this intricate give and take that may help explain mysteries of the self. “Empirical science, empiricism, takes no account of the soul, no account of what constitutes and determines personal being,” Oliver Sacks once wrote, while contemplating a patient who had lost his memories. Sacks asked: Was it possible that his patient “had really been ‘desouled’ by a disease?”

One afternoon, Ramírez-Bermúdez and I drive to the Cuicuilco pyramid, a grassy hill of meticulously arranged stones that has become a mecca for Mexico City residents on the Day of the Dead. He tells me that people celebrate with skulls and yellow marigolds, calling on souls to return. The living leave favorite foods and candies of their dead loved ones as offerings, and unroll bedding on which the resurrected can rest when they arrive.

Ramírez-Bermúdez’s descriptions of the traditions remind me of my childhood visits to Japan, how my Buddhist aunts would leave sake and cigarettes on an altar for my dead grandfather. So many of us grow up hearing about the soul, about life after death, in whatever form. We want to believe in it. In The Denial of Death, Ernest Becker said awareness of our own death made each of us strive to reach a level of “immortality” through our behavior and choices.

Ramírez-Bermúdez tells me he grew up with the same Day of the Dead traditions as his neighbors. But his interest in the brain did not mesh well with the spiritual beliefs of his country. In Mexico, he tells me, neurologists are not regarded with the reverence that they might receive in the U.S. or other countries. It’s hard to swallow the idea that the self, or the soul, can be boiled down to a tangle of emotions, perceptions, and neurological connections, which can be altered with a simple interruption to wiring.

We don’t want to believe those parts that make us who we are can so easily be obliterated. As in any gripping apocalyptic tale, it is always about us. Our survival. Our continuity and feelings. When we consider the mentally ill and brain-damaged, people who seem to have lost their memories or themselves, it often becomes all about us, too. Do most of the demented worry about that which they can no longer do? It’s like asking if the dead fret over being dead.

We create the line between life and death. Impose it. Debate it. When does a life actually begin? And when does it officially end? “When you lost your mind, you lose yourself,” wrote Lauren Kessler, in Dancing with Rose, about her time working in a dementia facility. “The walking dead. Give me anything, but spare me this disease.”

We fail to realize that they are us. If Cotard’s patients have anything in common with the fictional undead, I now understand it is this: Both allow us to scrutinize, to fantasize about, to wonder about that line. Thin as a vein. Fragile as a feeling. Vulnerable as the ego itself.

This story was written by Erika Hayasaki, edited by Madison Kahn, fact-checked by Sarah Sloat, and copy-edited by Lawrence Levi. Original photographs by Eunice Adorno for Matter. Conceptual photographs by Marlous van der Sloot.

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