Your brain is a complex organ that is constantly working to keep you functioning and alive. It keeps you walking, talking, and just being human. However, we all know that things can go wrong with the brain. In fact, 18.2 percent of us suffer from some form of mental illness every year.

It’s likely that you’ve heard of conditions like depression, bipolar disorder, and schizophrenia. But you may not have heard of the conditions described below, which can alter the way you perceive the world or even make you think that your family members are impostors.

10 Akinetopsia

Everyone knows about the common condition known as color blindness, so you may find it relatively easy to understand what it’s like to be missing some or all colors from your vision. But can you imagine losing your ability to see motion?

This is called akinetopsia. One of the few known patients, a mother referred to as “Patient LM,” was diagnosed with the condition in 1978 at 43 years old. To her, the world looks like she’s watching a movie but only seeing a frame every so often.^[1]

Patient LM was first admitted to the hospital with complaints of severe headaches. She had suffered a stroke which resulted in damage to her middle temporal visual area (MT or V5). This region of the brain is believed to be responsible for perceiving motion. Fortunately, she retained all other visual abilities, such as depth and color perception.

9 Losing Your Own Body

At age 19, Ian Waterman suffered a near-total loss of his sense of touch as well as proprioception, the ability to know where your body parts are. Without proprioception, the movements that you have been able to do your whole life without much thought (such as walking) become almost impossible.

Waterman was told that he probably wouldn’t walk again and would be confined to a wheelchair for the rest of his life. He was too stubborn for that, though. To perform many movements, he learned to replace his lost proprioception with his eyes and to plan all movements in advance.

With a lot of practice, he has regained his ability to make normal arm and hand movements. However, he still describes his walking as “controlled falling.”^[2]

8 Prosopagnosia

Prosopagnosia was introduced into popular culture when Brad Pitt stated that he may have this condition. In an interview with Esquire in 2013, he said that he should get tested.

Prosopagnosia is the loss of the ability to recognize people’s faces. However, you can still identify them from other characteristics, such as a unique smell or style of clothing.

Until quite recently, it was believed to be a rare condition that only occurred in those with neurological damage—for example, someone who has suffered a stroke or head injury. However, it has been seen in people without such damage. It’s now believed that around 1 in 50 people experience prosopagnosia.^[3]

Another common belief is that prosopagnosia is associated with autism, but this is not the case. Although people with autism sometimes experience face recognition difficulties, the two conditions do not appear to be linked.

7 Capgras Delusion

Imagine a scenario where someone you know suffers a traumatic head injury in an accident but luckily survives. Then the person wakes up and no longer believes that you are you. Instead, he thinks you’re an impostor.

This is known as the Capgras delusion and is believed to occur after someone sustains damage to the superior temporal sulcus, an area in the brain believed to be important in attributing emotional feelings to a person.

Even though the sufferer can still recognize faces, he can’t attribute feelings to the recognized individual and so believes that person to be an imposter. This also applies to the sufferer’s pets. He will believe that one of the impostors living with him has also replaced his dog.^[4]

Even stranger, those with the delusion often know how absurd these feelings are. But as the visual sense is so dominant in humans, they find it hard to disregard the feeling that everyone they know has been replaced.

6 Urbach-Wiethe Disease

Ever think it would be nice to be fearless? Patient SM, who suffers from Urbach-Wiethe disease, experiences just that. The disease causes both of her amygdalae (believed by many to be the fear centers of the brain) to selectively deteriorate.

To test whether SM’s fearlessness applied to a variety of situations, psychologists took the woman to the haunted house at Waverly Hills Sanatorium in Louisville, Kentucky. When she was going through the house, SM was not scared whatsoever. Instead, she smiled and laughed at the haunted house.^[5]

As some people don’t find haunted houses scary, the psychologists took SM to a pet store after she said that she hated snakes. Once there, she rubbed their scales and held them. Psychologists reported that she acted curious and interested rather than frightened of the snakes.

5 Kluver–Bucy Syndrome

At age 19, “Kevin” (probably not his real name) was a law-abiding citizen who began to experience “attacks” of deja vu as often as 20 times a day. Other symptoms included sharp chest pains, breathlessness, and even musical hallucinations.

All of this was diagnosed to be a result of epilepsy, which was found to be caused by the right mesial temporal lobe in his brain. At age 39, Kevin underwent surgery to remove the part of his brain that was causing the issues.

About a month after the surgery, he experienced serious behavioral changes. He developed an insatiable appetite for food and sex and eventually began downloading and viewing child porn.

Kevin was diagnosed with Kluver–Bucy syndrome. After his arrest, the defense argued that he was not in control of his actions due to his condition. As a result, he was given a reduced sentence.^[6]

4 Guillain–Barre Syndrome

When you have Guillain–Barre syndrome, your immune system attacks your peripheral nervous system, which carries information between your central nervous system (your spinal cord and brain) and the rest of your body. Guillain–Barre leads to weakness, numbness, and tingling throughout your body. Eventually, this can lead to paralysis.^[7]

Although the cause is unknown, this disorder is believed to be triggered by a stomach flu or lung infection. Luckily, it only affects about 1 in 100,000 people, so there’s no need to worry too much.

3 Rett Syndrome

Rett syndrome affects babies and occurs almost exclusively in girls. Babies who are born with this syndrome appear to develop normally for about six months. Then they progressively lose their ability to control the muscles that help them move, coordinate, and communicate.

Babies with Rett syndrome often have smaller heads due to slowed brain growth. As they get older, this delayed growth becomes more noticeable in the other parts of their bodies.^[8]

For now, there is no cure. Current treatments attempt to improve the child’s movements and communication as well as support the family.

2 Bobble-Head Doll Syndrome

Bobble-head doll syndrome also affects children, often around age three. It causes them to bob their heads up and down or side to side. If they try, the children can prevent the bobbing. It also disappears when they sleep. But if the child becomes excited or isn’t concentrating, then the bobbing worsens.

As children spend a lot of time being excited or not concentrating, this can be quite a problem. Luckily, it does not appear to be fatal. In fact, the disorder can be cured quite readily as it is caused by a cyst in the brain. Once the cyst is removed, the syndrome either disappears or its symptoms are significantly reduced.^[9]

1 Synesthesia

For people with synesthesia, one sense, such as hearing a noise or smelling an odor, simultaneously activates another sense. Of course, not all individuals react to every stimulus. There are different kinds of synesthesia.

In the case of sight, you may see a specific color whenever you perceive a certain letter or number. With taste, a certain noise may trigger a specific taste in your mouth. Usually, only two senses are linked. However, in rare cases, synesthesia can link three or more. In fact, the word “synesthesia” comes from Greek and translates to “joined perception.”

Women are three times as likely as men to have the condition. Synesthetes are also more likely to be left-handed and have someone else in their families with the condition. Estimates of the number of people with synesthesia vary wildly—from 1 in 200 to as few as 1 in 100,000.

Although scientists don’t know which areas of the brain are involved with synesthesia, some believe that this condition is caused by “crossed wires” within the brain. Other research points to the limbic system (which regulates emotional responses) as being responsible for this syndrome.^[10]

The expression “it’s all in your head” can be used to support a strong case for almost anything that occurs in the world. Essentially, this forms the basis of Cartesian philosophy. And even while our understanding of reality and our place in it may have progressed beyond that, much of what we take to be true in the world is still undoubtedly made up.

In fact, several syndromes that can affect someone are essentially nothing more than our minds playing tricks on us, whether caused by popular culture, preconceptions, side effects of medical conditions, or something else entirely. So here are 10 fascinating syndromes that only exist in your head.

Related: Top 10 Rare Diseases That Change Your Appearance

10 Gourmand Syndrome

There are numerous adverse outcomes that a traumatic brain injury can induce. Undoubtedly, gourmand syndrome is one of the most peculiar. A sufferer of a certain kind of brain damage may develop an obsession with gourmet meals. It involves more than just indulging in delicious food—it involves talking, writing, and reading about it all.

Since the condition alters one’s relationship with food, doctors have classified it as a benign eating disorder. Lesions in the same region of the brain have been seen in most patients with the illness, indicating that trauma in that particular area is the cause.

The illness was initially noted in the 1990s, and a political reporter who experienced it in one instance changed careers to become a cuisine writer.^[1]

9 Daughter from California Syndrome

You might be familiar with daughter from California syndrome if you work in the medical field. That’s the word for a phenomenon that has been seen repeatedly by healthcare professionals when interacting with elderly or terminal patients. Although it’s a really depressing scenario, it happens frequently enough for the professionals to have given it a name.

As a patient approaches the end of their life, it occasionally happens that a relative who has never paid them a visit shows up, knowing that the patient’s time is running out. This individual—dubbed the “Daughter from California”—has a brazen demeanor, tries to handle every facet of the dying patient’s care even though they have never been involved before, and acts as though they are more knowledgeable than the medical staff who have been providing care for the patient the entire time.

It’s thought that they typically seek drastic measures to save their relative’s life since they feel guilty and deny ever being involved in the first place. Even if they are merely in the way, they have this mental notion that they can take control and make things different.^[2]

8 Third Man Syndrome

Third man syndrome, one of the most enigmatic illnesses you’re likely to read about, is frequently described as just having a guardian angel. Numerous accounts indicate that people have seen a mysterious presence with them in situations where survival is at stake. While exploring Antarctica in the early 1900s, Sir Ernest Shackleford was among the first to write about this occurrence. He wrote of journeying across the icy landscape with two other men in his notebooks, and at one point, he felt as though they were truly traveling with a fourth person.

Since Shackleford’s time, other individuals who have encountered dire situations have also sensed the presence of a different entity, a kind of guide. These have included mountain climbers, explorers, and survivors of shipwrecks. Frank Smyth attempted to ascend Mount Everest in 1933 and experienced a mysterious companion who helped him overcome his feelings of loneliness.

At one point, he broke his food rations in two and attempted to give them to the man who wasn’t there since his feelings for Smyth were so strong. It was even physical for Ron DiFrancesco, the final survivor of the South Tower. He claimed to have felt someone take his hand and lead him out of the smoke.

The science underlying the phenomenon is not fully understood because it has not been thoroughly explored. Some contend it could be a guardian angel, but some propose this is a natural human survival response. In the worst situations, a method to gather your thoughts and concentrate on preserving your own life.^[3]

7 Anton Syndrome

We are aware that denying reality when faced with issues like illness or death is typical. However, the precise way that shows up can be unexpected. Patients who suffer from blindness but refuse to accept it can develop Anton syndrome. Those who have it deny that they are blind and instead make up stories or reasons for what they think they see. In a case from history supposed to represent Anton syndrome, the patient merely insisted on being transferred because she thought every room she was in was too gloomy.

In the face of evidence that they are blind, sufferers will not accept that they are blind. Instead, they will invent stories to explain their blindness and act as though they can see objects or persons in the room that aren’t there.^[4]

6 Stendhal Syndrome

There are people out there who take art very seriously. You could even have witnessed or known someone who intensely reacts emotionally to works of art. Maybe that’s what art is all about. To evoke emotions in others. However, Stendhal syndrome elevates this to a new plane.

Thousands of visitors visit Florence, Italy, each year to view the artwork there. A small percentage of those countless visitors will cry because they are so moved by the artwork they encounter.

The condition can cause dizziness, heart palpitations, hallucinations, and panic attacks in those who experience it. Researchers believe it happens when one is exposed to so much exceptional and historical art that it overwhelms the senses, a phenomenon known as an “Art Attack.” In 1989, psychiatrists properly recognized the ailment as a psychiatric disease.^[5]

5 Capgras Syndrome

The idea that something or someone significant has been replaced by an identical replica is known as Capgras syndrome. The illness is not limited to mental health; it may also result from neurodegenerative diseases or brain trauma. The typical symptoms of the condition involve the belief that a loved one or someone close to them has been switched. But it also seems that some individuals may assume that specific items or pets have been victims of the same replacement plan.

Those who experience the illness may think that a fake has temporarily replaced a loved one or that it has happened over a longer period. Additionally, they think that the imposter’s identity can be determined by modest physical cues. They think this will allow them to distinguish between the real person and the impostor.^[6]

4 De Clerambault Syndrome

Most of us have likely experienced unrequited love at some point. You must simply roll with the punches and carry on with your life because it’s an inevitable thing. Clerambault syndrome is a disorder in which you believe someone else is longing for you rather than the other way around.

Also known as erotomania, it is defined as the hallucinatory conviction that you are the object of someone else’s romantic or professional admiration. Almost usually, women receive a diagnosis; however, there have been rumors that men may not be receiving enough diagnoses. The state can be short-lived or have lasting effects, with the person believing they are being sought after and that the other person is infatuated with you while not feeling the same way.^[7]

3 Salieri Syndrome

Italian musician Antonio Salieri has a lengthy history of being linked to a rivalry with Mozart. This rivalry has even been the subject of a short novel, an opera, and the film Amadeus. There isn’t much evidence to support the existence of rivalry in real life. And none that Salieri attempted to poison Mozart ever did. It’s a good thing that reality is unimportant to this list.

The phenomenon known as Salieri syndrome occurs when individuals who may be highly skilled feel that someone more gifted is overshadowing them and, because of their jealousy, deliberately work to discredit their potential rivals. This has been investigated in group settings, where it has been demonstrated to weaken the group as a whole and lower everyone’s performance.

Despite being a historical relic, the name is most frequently used in professional settings. According to the group research, when an employee deliberately undermines someone else because they believe they are superior to them, not only does the target of the abuse suffer, but they also bring the entire workplace down with them. All this solely depends on how they view themselves and their place in the dynamic. Everyone now does poorly, even though they may have done well if they had left well enough alone.^[8]

2 Chinese Restaurant Syndrome

How do you feel about MSG? For many years, monosodium glutamate was demonized in the media and seen as a hazardous food additive that, if you were ever exposed to it, would endanger your happiness and health. At one point, the situation became so severe that people began blaming their diseases and the adverse effects on consuming Chinese food. They referred to the phenomenon as “Chinese Restaurant Syndrome,” which was supposedly caused by the widespread usage of MSG in the meals at the time.

The peculiar thing about MSG is that it isn’t some bizarre artificial substance. It is made from L-glutamic acid and is found naturally in various foods. It can be made by fermenting carbohydrates such as molasses or beet sugar. Additionally, it can be found naturally in several foods, such as cheese and tomatoes.

Chinese cuisine syndrome is said to induce a wide range of symptoms, including weakness, perspiration, nausea, and headaches. The issue is that there has never been solid scientific evidence connecting this to MSG. While Chinese restaurants became more and more famous in the West throughout the 1960s and 1980s, this purported condition gained notoriety at the same time. However, it is now thought that a large portion of the so-called symptoms and MSG’s demonization are the result of ignorance and prejudice.^[9]

1 Puppy Pregnancy Syndrome

Puppy pregnancy syndrome is a disorder like no other. If for no other reason than the fact that it sounds completely fictitious and the people who experience it are obviously not telling the truth. Nevertheless, it has happened multiple times, and researchers have identified the syndrome’s symptoms.

The illness, which appears to be primarily confined to one region of India, seems to be cultural. After being bitten by a dog or coming into contact with one, six men and one woman said they were certain the dog had gotten them pregnant. They thought they were carrying a puppy litter. While a small percentage of those who reported having the illness did have some history of mental health issues, the majority did not. The only similarity between them was that they all came from rural areas close to Calcutta.

Few in the village deny the condition’s plausibility; the great majority of residents think it is totally real. Dog saliva is believed to have the potential to make someone pregnant, particularly if the dog bites the person while it is very aroused. Nobody explained how they arrived at that decision.

Males are reported to die if they bring their puppy litter to term. However, local healers are said to have the ability to treat the condition—possibly for a charge.^[10]

You can make a convincing argument that the phrase “it’s all in your head” applies to pretty much everything in the world. This is, more or less, a cornerstone of Cartesian philosophy. And while maybe we have advanced beyond that as it relates to reality and our place in it, that’s not to say there isn’t plenty that we perceive in the world that is just made up. Whether it’s a cultural phenomenon, a bias, a side effect of an illness, or something more, there are plenty of syndromes that one can be afflicted with that boil down to little more than our minds playing tricks on us. 

10. Chinese Restaurant Syndrome 

What is your opinion of MSG? for years monosodium glutamate was vilified in the media and considered a dangerous food additive that was risking your health and happiness should you ever be exposed to it. It got so bad at one point that the name “Chinese Restaurant Syndrome” was coined to explain the series of illnesses and side effects people claimed to be suffering from after eating Chinese food, ostensibly because MSG was a common ingredient in the cuisine during this time.

The thing about MSG is that it’s not some strange synthetic chemical. It actually exists naturally in some foods and it’s derived from L-glutamic acid. You can produce it by fermenting it from carbs like beet sugar or molasses. It also occurs naturally in several food products including tomatoes and cheese.

Chinese food syndrome supposedly caused all kinds of symptoms ranging from a headache to nausea to weakness and sweating. The problem is that no science has ever conclusively linked this to MSG. While this alleged condition rose to prominence in the 1960s and through the 80s, along with the rise in popularity of Chinese restaurants in the West, it’s believed today that much of the so-called symptoms and demonization of MSG simply came from prejudice and ignorance. 

9. Salieri Syndrome 

Antonio Salieri was an Italian composer and has long been associated with a rivalry between himself and Mozart. There is even a short story and subsequent opera based on this rivalry, not to mention the movie Amadeus. However, in real life there’s actually little evidence to suggest any rivalry existed. And certainly none that Salieri ever tried to poison Mozart.  Good thing this list isn’t concerned with reality.

Salieri Syndrome is the name for a phenomenon where people who may actually be quite talented feel like they are being overshadowed by someone more talented and go out of their way to undermine their would-be rivals out of a sense of envy. Researchers have studied this in group settings where it has been shown to undermine the entire group and make everyone’s performance worse. 

Though the name is borrowed from history, it is most often observed in the workplace today. As the group research shows, if one person at work is actively undermining someone else they think is better than them, not only will the person they are undermining suffer, but they bring everyone in the office down with them. This is all purely based on their own perceptions of themselves and how they fit into the dynamic. Had they left well enough alone they, and everyone, might have done well, but now all do poorly.

8. Third Man Syndrome 

One of the most mysterious conditions you’re likely to hear about, Third Man Syndrome has sometimes been referred to as simply having a guardian angel. Reports show, and in more than one instance, when a person faces a life and death scenario that they have perceived a mysterious presence with them. 

In the early 1900s, Sir Ernest Shackleford was one of the first people to write about this phenomenon as he explored Antarctica. In the journals he wrote on his journey, he recorded traveling across the frozen landscape with two other men and feeling at some point that there was actually a fourth person there with them. 

Since Shackleford’s time, other people who have found themselves in extreme circumstances have also felt another presence with them, a guide of sorts. This has been shipwreck survivors, explorers and mountain climbers. In 1933, Frank Smyth tried to summit Mt. Everest and felt a mystery companion staving off loneliness as he climbed. 

The feeling for Smyth was so real that at one point he stopped to eat, broke his food rations in half, and tried to hand them to the man who wasn’t there. For Ron DiFrancesco, the last survivor to escape the Twin Towers, it was even physical. In the smoke, he said he felt someone take his hand and guide him out.

The phenomenon is not well studied, so the science behind it is not entirely well known. While some people would argue that it may actually be a guardian angel, it has also been suggested that this is part of a survival response humans have. A way to center yourself and focus to save your own life in the most dire circumstances. 

7. Puppy Pregnancy Syndrome 

You’ll be hard-pressed to find a stranger condition then puppy pregnancy syndrome. if for no other reason than it sounds like it’s entirely made up and the people who suffer from it can’t possibly be telling the truth. Despite this, it has occurred more than once and researchers have documented symptoms of the syndrome.

The condition that seems to be cultural, and occurs almost exclusively in a certain part of India. Six men and one woman reported having been bit by or had some other contact with dogs and, afterwards, were convinced that the dog had impregnated them. They believed they were carrying a litter of puppies.

Although some people who claim to be suffering from the condition had some evidence of psychiatric conditions in their past, most of them did not. The only thing they had in common was that they were from the same rural area near Calcutta.

The vast majority of people in the village believe that the condition was entirely real, with very few doubting that it was possible. The people believe that dog saliva could cause pregnancy, especially if the dog was in a state of arousal when it bit the person. No explanation was given how anyone came to that conclusion.

Local healers are said to have the power to cure the condition, presumably for a fee, which is entirely necessary since males are said to die if they carry their puppy litter to term. 

6. Anton Syndrome

We know that denial is common in dealing with things like death or disease. But just how that manifests can be surprising. Anton syndrome occurs in patients who are suffering blindness but will not acknowledge that fact. Those who suffer from it do not acknowledge they are blind and instead create excuses or fantasies about what they are actually experiencing. In one historical case from ancient Rome believed to be Anton syndrome, the patient simply believed all the rooms she was in were too dark and demanded to be moved elsewhere. 

Sufferers will refuse to acknowledge their blindness, and even in the face of proof that they can’t see where they are and what they’re doing, will simply make up stories to account for that and pretend they can see things or people in the room, even if they aren’t there.

5. Stendhal Syndrome 

Some people take art extremely seriously. You may have even known or seen someone who has a serious emotional reaction to certain pieces of art. Perhaps maybe that’s the point of art. To elicit feelings in people. But Stendhal Syndrome takes this to the next level.

Every year, the city of Florence, Italy hosts thousands of tourists who come to see the art there. Among those many travelers there will be a handful of people who break down after being overwhelmed by the art they see there. 

Those who experience it may endure dizziness, hallucinations, heart palpitations and panic attacks. Researchers attribute it to taking in so much historic and remarkable art that it overwhelms the senses in what is sometimes called an Art Attack. Psychiatrists fully classified the condition as a psychiatric disorder in 1989.

4. Gourmand Syndrome 

There are a lot of side effects that one can experience because of a traumatic brain injury. Gourmand syndrome is arguably one of the most unusual. After a certain brain trauma a victim can become obsessed with the idea of fine dining. That’s not just eating fine food, it’s reading about it, writing about it, chatting about it, the whole nine yards.

Doctors classified the condition as a benign eating disorder, since it affects the way you relate to food. Most of the sufferers of the condition have exhibited lesions at the same part of their brain, showing that trauma in the specific area is the cause. 

The condition was first described in the 1990s, and in at least one case a political reporter who suffered from it switched to a food writer.

3. Capgras Syndrome 

Capgras Syndrome is the belief that someone, or something, close to you has been replaced by an exact duplicate. The condition is not just psychiatric, it can be because of an injury to the brain or neurodegenerative conditions as well. Typically, someone suffering from the syndrome will believe that a person close to them like a loved one has been swapped, but apparently a person can also believe certain objects and pets may have fallen victim to the same replacement scheme.

Those who suffer from the condition may believe that an imposter has replaced their loved one only briefly, or it can be over an extended period. They also believe that there are subtle physical clues that let them know the imposter isn’t the real person. In this way they believe they can tell the difference between the real person and the imposter. 

2. De Clerambault Syndrome

Most of us have probably dealt with unrequited love in the past. It’s a thing that happens, and you just have to roll the punches and move on with your life. There’s a condition called Clerambault Syndrome where it’s not you longing for someone else, but you convinced someone else is longing for you.

Also called erotomania, it’s characterized as a delusional belief that someone, often considered to be of higher professional or social standing, is in love with you. It’s almost always women who are diagnosed, but it’s been speculated the occurrence in men is underdiagnosed. The condition can be brief, or it can last decades with the person convinced that you’re being pursued and the other person just won’t leave you alone because they love you so much, even though none of it is felt by the other party.

1. Daughter from California Syndrome

If you work in healthcare, you may have heard of Daughter from California syndrome. That’s the name for an observed phenomenon that healthcare workers have encountered many times when dealing with elderly or terminal patients. It’s a bit of a sad situation, but it occurs enough that the entire industry has adopted a name for it.

What happens is, as a patient nears the end of their life, sometimes a relative who has never come to visit the dying patient will arrive knowing that the end is near. This person, the so-called Daughter From California, has a brash attitude and attempts to take over all aspects of the dying patient’s care despite having never been involved before, and acting like they know best rather than the healthcare professionals who have been tending to the person the entire time.

They demand extreme methods to save the life of their relative, and it’s believed this is generally out of a sense of guilt and denial for having never been involved previously. They make up this idea in their head that they can change things by taking over even though they’re just in the way.

Nearly everyone has a family member or friend who suffers from cancer, diabetes, or heart disease. Reality is often stranger than fiction. There are some syndromes out there that are so incredibly rare, you may be shocked to learn that these diseases can actually happen.

10. Alice in Wonderland Syndrome

In Lewis Carroll’s famous children’s book Alice’s Adventures in Wonderland, the body of the hero, Alice, grows bigger after drinking from a mysterious bottled labeled “drink me,” and the rest of the objects around her became small. While most people would assume this is just one of many scenes from the book that only exist in a world of fantasy, people actually suffer from a real condition that alters their perception, making them feel as though people and objects around them have either become very, very small, or grown to gigantic proportions. This phenomenon is known as Alice in Wonderland Syndrome.

While this sounds like a psychological hallucination, it’s actually a result of an adjustment in the parietal lobe of the brain. Your eyes simply perceive objects at the wrong size, even if your mind is fully aware that it’s not real. Migraine headaches and fevers can sometimes trigger these visions. It can also be triggered by stress, an infection, and of course, taking drugs. Even drugs as mild as cough medicine have been known to bring on these hallucinations.

Lewis Carroll was known for having severe migraines, and he also drank laudanum on a regular basis to help cope with the pain. Unfortunately, this liquid would have turned him into an addict, since it was a combination of opium, morphine, and codeine.  Many historians now believe that he was writing about his own experiences, and he was most likely terrified that he was going insane.

Episodes of Alice in Wonderland Syndrome come and go within a matter of minutes, and most people experience them at home. Dr. Sheena Aurora from Stanford University is the only physician who has managed to capture brain activity on an MRI while a 12-year-old girl was in the middle of having these visions. It turns out that electrical activity in the brain can sometimes cause abnormal blood flow, which causes the change in perception of object sizes. Aside from being a bit scary, this doesn’t seem to have any negative effects on the person’s health or day-to-day life.

9. Foreign Accent Syndrome

Usually, changing your accent can take years of living in a foreign state or country, or intently studying actors in foreign films and TV shows. But for some people, all it takes is a day of surgery and a long nap for them to wake up sounding like a totally different person.

Foreign Accent Syndrome is when someone suddenly changes their accent without warning. People typically get this syndrome after suffering from a brain injury or a stroke. In the case of a woman named Lisa Alamia from Texas, she woke up with an English cockney accent after she had surgery on her jaw to fix an overbite.  Sometimes, the foreign accent patients develop doesn’t fit in with any country at all, because it really is just speech patterns that are affected by either their tongue placement, or the part of the brain that helps them process languages. While there is no easy cure for this syndrome, patients can attend speech therapy, if they really want to go back to their original accents.

8. Alien Hand Syndrome

Imagine that your hand had a mind of its own, and that it did whatever it wanted. It starts slapping you in the face, or picking up items off the shelves in the stores and throwing them in your cart without warning. This is Alien Hand Syndrome, and it can be caused by damage to the brain and nervous system after a seizure, brain tumor, or stroke, or surgery.

You have probably seen a baby who can’t help but grab at almost anything you put in front of them. As an adult, you have developed impulse control, and your brain knows better than to reach out for anything and everything. But people who suffer from this syndrome cannot control one of their hands, and it will reach out and grab or slap objects in front of them, because it becomes almost like a reflex. In many cases, this can get people into a lot of trouble when they are out in public. Patients who to go to physical therapy often walk with a cane, even if they don’t really need one, simply to keep their alien hand occupied.

7. Paris and Jerusalem Syndrome

There is a saying that you should never meet your heroes, because you’re bound to be disappointed. The same holds true for the places in the world that you have built up in your mind as being these amazing cities, because the disappointment can be so harsh, it literally sends people to the hospital.

The two places in the world that affects the most people are Paris and Jerusalem. Japanese people in particular have a tendency to romanticize Paris, France as this place where they can show up and find the love of their life. When they get there to realize the Eiffel Tower isn’t that much different than its counterpart in Tokyo, many people start to have extreme anxiety attacks and bouts of depression that are so bad, they end up in the hospital.

In a similar fashion, Christians build up the idea of Jerusalem as being such a wonderful and holy place. Many people have convinced themselves that if they visit, there will be a miracle, and somehow, their lives will be changed forever. It might actually be better to leave disappointed, when you consider the alternative. In 1992, a Canadian tourist visiting Jerusalem had such an intense religious experience, that he claimed he was the Biblical character Samson. He was sent to a local psychiatric hospital. When the doctors in Jerusalem were interviewed by the New York Times, they said that a patient claiming to be Samson was a new one. Usually, people like to think they’re Jesus.

6. Hallermann-Streiff Syndrome

With fewer than 250 people known to have the disease, Hallermann-Streiff Syndrome is one of the rarest conditions in the world. There are 28 abnormal characteristics that doctors use to diagnose someone with HS Syndrome. That’s far too many to list here, but the most common attributes are distinct facial features with small, close-set eyes and beak-like noses. This is due to an underdeveloped skull and facial bones. There is also a lack of hair growth, dwarfism, and poor eyesight from cataracts. People who are born with Hallermann-Streiff Syndrome typically don’t suffer with any sort of learning disabilities. Mentally, they become fully grown adults, but they continue to live in child-like bodies their entire lives.

A woman named Michelle Kish is 20-years-old, but she is often confused with being a small child. During an interview with the BBC, Michelle’s parents said that during her pregnancy and birth, everything seemed absolutely normal. They didn’t know about her diagnosis until after she was born, and they took her to a geneticist. HS Syndrome happens completely at random, and it occurs in one out of every 5 million births. Michelle spends a lot of time in and out of hospitals for her medical difficulties, but she is otherwise a very happy and intelligent lady.

5. Glass Syndrome

Osteogenesis Imperfecta, also known as “Glass Syndrome” or “Brittle Bone Disease,” is when a child is born with extremely fragile bones that can break from even a gentle touch from another person. They can even break a rib from coughing or laughing too hard. In most cases, they will already start breaking their bones when they are inside the womb. Because of this, their bones can never grow to their full potential, often leaving them physically unable to walk.

An Australian actor named Quentin Kenihan proves that people with brittle bones can still live their lives to the fullest. He is a filmmaker, actor, director, author, and public speaker. He got a part in Mad Max: Fury Road in 2015, and is one of the few disabled actors in history to appear in an Academy Award winning film.

4. Blue Skin Syndrome

Before the invention of antibiotics, doctors prescribed “colloidal silver” for a litany of medical problems, but today, doctors no longer prescribe it because it can causes a condition called Argyria, where a person’s skin turns blue. It turns out that if humans come into contact with too much metal in the blood steam, it will actually change their skin color. It is believed that the term “blue blood” came from the fact that people in aristocratic families ate all of their food and drink from real silver, and it must have tinted some peoples’ skin.

In 2008, a man named Paul Karason began taking a supplement called colloidal silver after seeing it advertised as a way to improve his health. He didn’t get out very much, and after months of taking colloidal silver every day, one of his friends asked what happened to his face. He finally looked in the mirror, and saw that his entire body had turned blue.

There is actually another mysterious syndrome that can turn a person’s skin blue, as well. The Fugate Family is remembered as the “Blue People of Kentucky” because several members of the clan were born with blue skin, while others looked perfectly normal. This was caused by a syndrome called methemoglobinemia, which is an an increased amount of iron in the blood from poor oxygenation.

3. Cutis Laxa Syndrome

https://youtu.be/SWOFOyo0jc0

The movie The Curious Case of Benjamin Button depicts a child who was born looking like an old man, and he gets progressively younger as he ages. This disease truly does exist in real life, but unfortunately, most people born with this don’t get to grow up to be Brad Pitt.

Bancroft TV filmed a documentary about a young woman named Zara Hartshorn, who suffers with the rare condition, which is called Cutis Laxa Syndrome. This causes skin to sag prematurely and gives someone the appearance that they are much older than their actual age. Sometimes, the syndrome can manifest with internal issues normally associated with the elderly as well, like heart and lung complications. While the sagging skin is strictly a cosmetic issue, it can completely destroy the person’s self-esteem. This issue is also genetic, so parents with Cutis Laxa Syndrome will pass it down to their children or grandchildren.

There is not much that can be done to cure the syndrome, beyond getting plastic surgery. Zara Hartshorn chose to get a facelift when she was just 16-years-old to help improve her appearance.

2. Sleeping Beauty Syndrome

Klein Levin Syndrome, also known as “Sleeping Beauty” syndrome, usually begins in someone’s teen years. While it’s normal for growing teenagers to enjoy sleeping in, Klein Levin Syndrome causes someone to fall asleep for weeks, or even months at a time.

It is usually triggered by catching a virus, like the flu, and it causes a disruption in the immune system. People who suffer with this disease begin to act like a bear that is about to go into hibernation. They will often lose weight during the course of their slumber, only to wake up half-asleep and extremely irritable. They eat as much food as they possibly can, before going back to sleep.

For the people who suffer from Klein Levin Syndrome, they miss out on school, but also on family vacations, birthdays, and other important events in their lives. Unfortunately, there is no cure, but doctors are trying hormone treatments and other medications to help reduce the sleeping episodes. Thankfully, some people can grow out of it once they become adults.

1. The Bubble Boy (Severe Combined Immunodeficiency)

In 1971, a baby named David Vetter was born with a condition called Severe Combined Immunodeficiency. David’s mother’s first child died of an infection soon after his birth, so they knew to quickly transfer baby David to a sterile environment before he could be exposed to germs.

David spent the rest of his young life inside of a bubble. He was put on the news, where many people reached out to offer help. NASA even developed a special suit that enabled him to walk around for the first time. In 1975, the movie The Boy in the Plastic Bubble, starring John Travolta, premiered, loosely based on David’s life story. That film, in turn, helped inspire the 2001 movie Bubble Boy.

When people saw footage of David in the news, the public criticized his mother for keeping him in the bubble his entire life, even though it was the only thing keeping him alive. They knew that the arrangement could not last into his adulthood, and doctors around the world began to suggest possible cures for his disorder.

Desperate to find a cure, David’s mother agreed to allow doctors to try an experimental procedure. They wanted to give him a bone marrow transplant from his sister, in the hopes that it could help his body form a healthy immune system. He was taken out of his bubble just long enough to have the surgery. But unfortunately, that short time out of his bubble truly did kill him about a week later.

After David’s death, doctors have since discovered that if a baby is born with this disease, their only chance of a cure is to give them a bone marrow transplant when they are still an infant, or in the womb. This method has a 95% chance of helping the baby develop a healthy immune system for the rest of their life.