When Eric Haller gets sick and goes into an "episode" -- about eight to 10 times a year -- he slips into a dreamlike state and is unable to do simple cognitive tasks, like reading, adding up numbers or comprehending his favorite TV shows.
The 21-year-old from Placentia, Calif., has a 3.5 average at Fullerton State University and interns for the L.A. Clippers, but his capabilities disappear when he descends into a trance.
Haller has Kleine-Levin syndrome, a rare sleep disorder that is characterized by recurring but reversible periods of excessive sleep, sometimes up to 20 hours per day, accompanied by childlike behavior.
Just last week, he came out of an episode that lasted 30 days. The one before that was 37 days.
"When I go through it, it's complete hell for me," said Haller. "It doesn't feel real and it's hard to understand what people are saying. It's so frustrating, because I want to understand."
Symptoms include excessive food intake, especially "junk food," plus "irritability, childishness, disorientation and hallucinations," according to the National Institute of Neurological Disorders and Stroke.
More than 70 percent of those who have KLS are male, and it affects only about 1,000 children and young adults worldwide.
Doctors know little about the disorder but suspect it may be related to a malfunction of the hypothalamus and thalamus, parts of the brain that control appetite, sleep and sexuality.
The disease is typically diagnosed around age 11, and episodes eventually decrease in frequency and intensity over the course of eight to 12 years.
The hardest part is psychological for both KLS patients and their caregivers, who report feeling the stress of this capricious condition.
Sometimes, patients babble like babies, barely incomprehensible -- and others can act out sexually.
Haller is an avid sports fan, but he could barely remember the Super Bowl, which had taken place during his last trancelike episode. It was just too taxing for him to follow.
Often these children are sent for psychiatric evaluation or misdiagnosed with mood or behavior problems. It took doctors four years to diagnose Haller with KLS.
In between episodes, those affected are perfectly normal, and the memories of how they behaved are "hazy," according to Haller.
"Normally, Eric is a loud mouth, a sport-loving guy," said his mother, Lori Haller-Schiller. "I never know when it will come on. It's like a light switch and he turns into a child. He likes sleeping and is very crabby and doesn't like to talk."
He also gets fast-food cravings, according to Haller-Schiller, who is on the board of the KLS Foundation.
"Every day I go to Chick-fil-A and order a meal for three people. It's so weird, and the Gummy Worms.… He doesn't eat like that normally."
She said he will watch Seinfeld reruns for hours and resort to childhood cartoons. He misses about 100 days of reality a year, she said.
After coming out of the last episode, he was surprised to learn that Jeremy Lin had become world-famous, even though he works for a professional basketball team. Haller remembered he had seen him on the cover of Sports Illustrated, but thought, "What the heck is this?"
"I don't really know when it's coming on -- I get two or three days' warning, maybe," he said. "I wake up and feel a little off – not aware and everything seems dreamlike. I can function but it keeps getting worse, day by day."
His first episode happened at about age 11. "I was crying because I couldn't do basic math homework, and I was a very smart kid."
Haller-Schiller said it took two years to diagnose her son. His parents took him to a psychiatrist thinking he was depressed and then to a sleep specialist, but they could find nothing wrong. Eventually, doctors solved the mystery.
"The worst part is not knowing. But when we got to the remarkable stage when we could talk to someone for the first time, it was amazing," said Haller-Schiller. "It was bittersweet."
In public school, Haller was given an individualized education plan because the episodes disrupted his ability to do homework. He also cannot be left alone during these periods, according to his mother.
Haller and his family draw inspiration from AAlanna Wong of Seattle, who also has KLS.
Britain's Daily Mail newspaper described how the 22-year-old was first misdiagnosed with schizophrenia. One of her episodes lasted eight months.
Now, Wong writes a blog, My KLS Life, with stories and coping tips to help others.
Children Eventually Outgrow KLS
There are no effective drugs to treat the disorder, although some patients have had some success with lithium, which is used to treat bipolar disorder.
Like other parents, they are desperate to find relief during these KLS episodes and will try anything -- acupuncture, chiropractics and even smoking the hallucinogenic drug salvia.
Haller tried an oxygen chamber to no avail. He had such a bad reaction after trying the stimulant Provigil that he was hospitalized for two days.
He never knows when the episodes will occur or even how long they will last.
"The hardest part is time goes by so slowly and it's so frustrating," said Haller. "Movies I have seen before, I watch over and over, 15 times. And it takes me about two to three weeks to fully adjust after it's over. It's tough."
Many patients' families report that symptoms began after a viral infection, which may make the brain "more vulnerable" to KLS, according to Dr. Phyllis Zee, director of the Sleep Disorders Center and professor of neurology at Northwestern University.
The disorder seems to be more prevalent among Ashkenazi Jews and is sometimes seen in siblings, which would suggest a genetic predisposition.
"Structurally, you look at the brain and it's normal, except for its functionality," said Zee. Before KLS becomes full-blown, parents may notice a change in temperament or personality, confusion and prolonged sleepiness.
Some act out sexually when they are in an episode. "Imagine a teenager in front of his friends masturbating," she said. "People think either he is being an exhibitionist or he has a psychiatric condition. It's embarrassing."
One of Zee's KLS patients was referred to her because she was hospitalized "in a weird state."
"She came in hypersexual and was trying to make out with the nurses," she said. "Normally, she was a proper young woman."
Zee said patients will eventually outgrow the disorder, but they just don't know when.
"We never see it when patients are in their 40s," she said.
As for Haller, he knows how embarrassing KLS episodes can be. Now, he is open with his friends about his disorder, but is hesitant to share with strangers, especially when he has been out of school or work for an extended period of time.
"I don't want them thinking I am that kid with the sleeping disorder," he said.
In the meantime, he takes the attitude that the episode that ended a week ago will be his last and he takes care of himself.
Haller doesn't smoke or drink alcohol, gets plenty of sleep and limits his stress. He works out regularly at a fitness center.
"I take precautions and health steps," he said. "You've got to be smart with it and smart with yourself ... Honestly, I don't let it affect my life in least bit and I try to have a positive attitude. I don't let it hold me back."