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Thank you, Dr. Sacks -

The universally revered neuroscientist and writer Oliver Sacks helped clear the mist around neurology and made it easier for the general public to understand the many fascinating neurological conditions that exist. In his seminal 1985 book 'The Man Who Mistook His Wife for a Hat,' Dr. Sacks described some of the most perplexing conditions he encountered throughout his career. The book skyrocketed public interest in neurology, and this gallery will outline some of the most interesting conditions that some people really lived with.

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Mirrored-self misidentification -

Mirrored-self misidentification is exactly what it sounds like; people afflicted with this condition are unable to recognize their own reflection.

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Mirrored-self misidentification -

This condition is usually associated with people suffering from dementia and Alzheimer's, but can sometimes manifest on its own, too. To make things even stranger, most people with this condition are still able to recognize the reflections of other people they're familiar with, just not their own.

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Somatoparaphrenia -

One of the most confounding case studies laid out in Sacks' book concerns a case of somatoparaphrenia. In layman's terms, this means that an individual categorically denies the ownership of one of their own limbs.

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Somatoparaphrenia -

In the case of Dr. Sacks' patient, a man in a hospital would wake up from rest finding a leg in his bed, a leg he didn't recognize. While attempting to expel the limb from his bed, the patient would end up throwing himself onto the floor, bewildered by the fact that his whole body would follow the detached leg to the ground.

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Capgras syndrome -

Capgras syndrome is often known as the real imposter syndrome. Commonly associated with dementia, Alzheimer's and sometimes Parkinson's, Capgras syndrome is diagnosed when an individual becomes convinced that someone close to them has been replaced with a doppelgänger.

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Capgras syndrome -

The condition is named after French psychiatrist Joseph Capgras, who first observed and recorded the phenomenon in the early 20th century in a woman who was unshakably certain that her children, her husband, and her closest friends were actually clones of the people she once knew.

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Cotard's syndrome -

Cotard's syndrome is a heady and terrifying neurological condition that convinces those afflicted that they are, in fact, dead, and floating through life as a phantom. Interestingly, the condition doesn't cause feelings of panic or hellfire, but instead provokes feelings of quiet confusion, displacement, and sometimes guilt.

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Cotard's syndrome -

People affected by Cotard's syndrome are often convinced that, along with their soul, they have lost the physical parts of their insides as well, such as their brain, organs, or bones. In one of the earliest recorded cases of Cotard's syndrome, from 1788, it was reported that the patient strongly felt that she was meant to be in the ground, and tried to convince doctors, friends, and family members to bury her.

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Urbach-Wiethe disease -

The symptoms of Urbach-Wiethe disease are generally considered to be neurological, but the condition is caused by a specific physical event. Urbach-Wiethe can develop following the calcification of the amygdala, usually caused by a genetic irregularity.

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Urbach-Wiethe disease -

The symptoms of Urbach-Wiehte disease? The complete destruction of one's concept of fear. The amygdala is responsible for regulating the body's fear responses, such as a rise in body temperature, quickened heart rate, and conscious fear or nervousness. When the amygdala is calcified, it's unable to do its job, rendering those afflicted by the condition truly, literally, fearless. This might sound like a real-life superpower, but fear is a necessary emotion that is essential in keeping us alive and out of danger.

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Witzelsucht syndrome -

Some of the symptoms of Witzelsucht might sound familiar to anyone who watched Joaquim Phoenix in the 2019 film 'Joker.' The name, which combines the German words for "joke" and "addiction," says it all. People living with Witzelsucht syndrome are completely unable to stop joking around, even in the most serious or inappropriate situations.

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Witzelsucht syndrome -

People with Witzelsucht syndrome are constantly cracking jokes, making puns, and going on endless, pointless tangents, like the setup of a joke the punchline of which never arrives. This can make the lives of afflicted individuals and the people close to them exceedingly difficult.

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Prosopagnosia -

Prosopagnosia is a type of visual agnosia that might sound unfamiliar, because most people know it by its more common name: face blindness. Many people who have trouble remembering faces might joke about being face blind, but it is a very real condition that can make daily life difficult and confusing.

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Prosopagnosia -

Dr. Oliver Sacks explored the condition in the titular case study in 'The Man Who Mistook His Wife for a Hat,' and explained that the symptoms of prosopagnosia can extend far beyond simply not being able to recognize your friends. In extreme cases, people with face blindness might not even be able to differentiate a face from an object. In Dr. Sacks' story, the studied patient would literally mistake his wife for a hat, casually grabbing her head in an effort to retrieve his hat.

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Associative agnosia -

Another form of visual agnosia known as associative agnosia causes individuals to be able to recognize an object's uses and construction, but find it nonetheless impossible to name the object.

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Associative agnosia -

A person with this associative agnosia can look at a belt, understand that it is made of leather and some metal, and is used to hold their pants up. The word "belt," however, will escape them, and they may not even recognize the word when it is told to them.

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Mirror-touch synesthesia -

Synesthesia is the curious phenomenon of the five senses getting all mixed up in each other. For example, someone might visualize certain shapes when they hear certain sounds. Mirror-touch synesthesia takes it one step further, and projects the sensations of others onto someone else in a very real way.

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Mirror-touch synesthesia -

The most famous case of mirror-touch synesthesia involved a woman who claimed that she would feel the same things that the person she was looking at felt. If she saw someone get kicked in the knee, her own knee would throb with pain. Or if she saw two people embrace, she would feel as though she was being hugged herself. The strangest symptom emerged when she saw someone eating food; in this instance, she would feel as though someone was shoving food down her throat against her will.

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Alien hand syndrome -

Alien hand syndrome is similar to somatoparaphrenia in that the patient doesn't recognize their limbs as their own. Unlike the man who threw himself out of his bed, however, the limb affected by alien hand syndrome seems to have a mind of its own.

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Alien hand syndrome -

With alien hand syndrome, the limb in question doesn't simply lay limp, but rather seems to do whatever it wants. The limb's owner may demand that it reach for something, but the defiant arm or hand will refuse to do any such thing, or even reach in an entirely different direction.

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Hemi-spatial neglect -

Hemi-spatial neglect is a condition that usually manifests after a person has suffered a stroke, and essentially hides half of the world out of site.

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Hemi-spatial neglect -

It's hard to visualize how exactly half of the world disappears, but for example, someone with a plate full of food might eat half of their meal, and despite still feeling hungry and not totally satisfied, they are not able to recognize that there is more food on the plate to be eaten.

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Aphantasia -

Aphantasia can best be described as the absence of the mind's eye. People living with aphantasia are unable to visualize people, objects, or concepts in their head if the object or person in question isn't right in front of them.

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Aphantasia -

That's not to say that aphantasia renders the brain completely empty. People living with the condition are still able to store descriptions of things, persons, and concepts, but aren't able to actually picture these them. Someone can describe a red wagon from memory as a shallow metal box painted red with four wheels and a handle, but won't see anything matching that description in their head.

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Anterograde amnesia -

Amnesia has been widely studied, but remains one of the most perplexing neurological conditions out there. Anterograde amnesia is particularly curious in that instead of erasing memories it simply causes the brain to stop storing any new memories after a certain point.

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Anterograde amnesia -

The case described in Dr. Sacks' 'The Man Who Mistook His Wife for a Hat' involves a World War II veteran who hadn't stored a new memory since the end of the war. The man, referred to as Jimmie G., was perpetually stuck in 1945, and seemed completely oblivious to any of the events in his life or the world at large that came after. Even more interesting is the fact that the old man still behaved as a sharp and chipper young man, concerned with the things that most young men in the 1940s were concerned with. It was, however, very disheartening for Jimmie G. to forget where he was or what he was doing from minute to minute.

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Astasia-abasia -

Sometimes referred to as Blocq's disease, astasia-abasia is a neurological condition that causes individuals to feel perpetually off-balance. Astasia-abasia can be caused by Parkinson's, and makes getting from one place to another unscathed a constant battle.

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Astasia-abasia -

People with astasia-abasia can appear quite drunk when they walk, swaying to and fro and side to side, doing their best not to fall over. One man, a patient studied by Dr. Sacks, had the brilliant idea of fashioning a pair of glasses with a carpenter's level so that he could judge his balance by sight instead of actual balance.

Sources: (ScienceAlert) (All About Psychology) (Athena Care)

See also: Rare medical conditions with extremely bizarre symptoms

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