People with Alice in Wonderland syndrome have episodes where objects and even parts of their own bodies can seem much smaller or much larger than they actually are. Alice in Wonderland syndrome was first described in 1952, and was given its name in 1955 by John Todd, an English psychiatrist. The condition is mostly found in children, though that may be due, at least in part, to an unwillingness in adults to describe the distortions they see, says Annette E. Grefe, MD, a pediatric neurologist at Wake Forest Baptist Health in Winston-Salem, North Carolina. “This is conjecture, but some adults might be afraid that people would think they were kind of crazy, because what they experience sounds like a hallucination,” says Dr. Grefe. As Alice herself famously said in the book Alice’s Adventures in Wonderland, published in 1865, “This is getting curiouser and curiouser!” Here’s what it’s like to have Alice in Wonderland syndrome, as well as how it’s diagnosed and treated.

1. Things Appear Much Bigger or Much Smaller Than They Really Are

People with AWIS report perceiving changes in their surroundings, according to Anjan K. Chatterjee, MD, a neurologist at Penn Medicine in Philadelphia. “Usually, a bout includes either micropsia, where objects appear small, or macropsia, where things look bigger than they actually are,” says Dr. Chatterjee. In some cases, it’s not just an external object that seems to change size; people experiencing Alice in Wonderland syndrome may perceive their own body parts in a distorted way, either much bigger or much smaller, he says. “These episodes can last for minutes and sometimes longer — it’s not quick — or it’s a two-second thing where you rub your eyes and everything is better,” says Chatterjee. Understandably, people can have some anxiety and fear about what’s causing these perceptions, especially when they experience AIWS for the first time. For people who continue to have episodes, it can eventually be more mystifying than frightening, but it depends on the personality of the individual, Chatterjee says.

2. Lewis Carroll Himself May Have Had AIWS

Lewis Carroll (the pen name of Charles Lutwidge Dodgson) was the author of Alice’s Adventures in Wonderland, and it’s possible he was influenced by his own experience of migraine in writing the book. In the book, Alice finds a bottle labeled “Drink me,” and when she does, she shrinks to less than a foot tall. Almost immediately afterward, she consumes a cake that causes her to grow very tall, until her head hits the ceiling. “It actually turns out that the author Lewis Carroll probably had migraine, based on some of his diary entries,” says Chatterjee. It’s been speculated that he may have experienced Alice in Wonderland syndrome himself, and that may have been part of the origin of some of those unusual parts in those stories, he says.

3. Experts Aren’t Sure What Causes Alice in Wonderland Syndrome

We don’t know exactly what is going on to cause people to see objects as larger or smaller than they really are, says Grefe. “There are some theories that make sense from an anatomical basis,” she says. When Alice in Wonderland syndrome accompanies migraine, it may originate from the parieto-occipital part of the brain, according to Grefe. “The parietal area has to do with perception of the body and perception of space, and the occipital area has to do with vision,” says Grefe. When AIWS is related to epilepsy, it seems to originate in the frontal lobe, but there’s still a lot to be learned about that, she adds.

4. AIWS Is Rare but May Be Underdiagnosed

Alice in Wonderland syndrome is so rare that many experts may never encounter it in their career, says Chatterjee. But although experts agree that it’s rare, the overall prevalence isn’t known. To date, no epidemiological studies have been done that would show how common AIWS is in the population. And no universally accepted way to diagnose the syndrome exists either, according to a review published in June 2016 in Neurology Clinical Practice. Two people could present with the same symptoms, and one might get a diagnosis of AIWS and one might not. The lack of diagnosis may also be because some people don’t like to talk about their symptoms; they may fear that people will think they are hallucinating or have a mental illness. This situation was described in a first-person account published in The New York Times.

5. Alice in Wonderland Syndrome May Be Part of the Aura in a Migraine Attack

Although AIWS is very rare, when it is reported, it is often associated with migraine. “I think most typically it occurs as part of the aura, but it can happen during the headache as well,” says Chatterjee. And like other experiences of migraine aura, the perception changes brought about by Alice in Wonderland syndrome may occur without any headache at all, he says. When a person has a migraine episode without head pain, it’s called “typical aura without headache” or sometimes called a “silent” migraine, according to the American Migraine Foundation.

There are other conditions besides migraine associated with Alice in Wonderland syndrome, says Grefe. “This would include temporal epilepsy, as well as certain kinds of infections — viral infections, such as mono or the flu,” she says. Mono, or infectious mononucleosis, is most often caused by the Epstein-Barr virus (EBV), a kind of herpesvirus and one of the most common human viruses, according to the Centers for Disease Control and Prevention (CDC). Most people get it at some point in their lives. In rare cases, EBV can lead to complications such as encephalitis (swelling of the brain), which is often the cause of AIWS in children. Rarely, Alice in Wonderland syndrome is a sign of a stroke or brain tumor, says Chatterjee. “That’s very rare, and usually you would have many other symptoms in addition to the visual symptoms of Alice in Wonderland syndrome,” he says. AIWS may also be caused by certain drugs, such as LSD or other hallucinogens. And “there are definitely psychiatric disorders where those kinds of misperceptions are part of the symptoms,” says Chatterjee.

7. Treatment Involves Treating the Underlying Condition

Although no standardized guidelines on diagnosing AIWS have been issued by a medical organization, it’s strongly recommended that when a person has symptoms of the disorder, the various potential underlying causes be investigated with blood tests, EEG (electroencephalogram), and brain MRI. An EEG detects changes in brain activity and can be used to diagnose epilepsy and other seizure disorders. MRIs can help diagnose conditions such as tumor, infection, swelling, or damage caused by an injury or stroke. To diagnose for migraine, a physical exam and the person’s symptoms and medical history are examined. There’s no specific treatment for Alice in Wonderland syndrome, says Chatterjee. “The treatment depends on what’s causing the visual disturbance — if it’s migraine, we would use migraine medication. That would mean preventive medication if you have migraine frequently, and as-needed acute migraine treatment for the attack,” he says. If the Alice in Wonderland syndrome is related to seizure, then seizure medication would be appropriate, adds Chatterjee. “There’s something happening in the physiology of migraine or another underlying condition that’s kicking off these perceptual phenomena,” says Chatterjee. For that reason, you wouldn’t give medication specifically for the AIWS visual disturbance, he says. “That’s one thing that makes this different from hallucinations or delusions, where you might want to give people medications to try to suppress whatever is generating those visual images from the interior of our brains,” he says. Since Alice in Wonderland syndrome is not like that, you would treat people for their migraine or epilepsy or any other underlying cause, thereby treating the disorder itself, not the expression of the disorder, says Chatterjee.