In the blink of an eye, Katie O'Brien's view of the world can change. In seconds, the 19-year-old can feel as though she's living in a world that has shrunk to the proportions of a doll house. Other times everyday objects seem strangely large.
"Right when I wake up, that's when I'll start to see things differently," Katie said. "I was looking at the couch once and it looked like the couch just was growing. It was really weird. It was really horrible."
Katie said that she was more confused than frightened by the experience as a child. "I don't know if I was necessarily like, really scared. It was just something that didn't make sense. Something I didn't understand," she said.
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Katie's mother, Denise O'Brien, can relate, because she'd had some of the same bizarre experiences when she was a child.
"I just remember feeling really tiny and everything got really big," she said. "And then, it reverses. … I mean, you know it hasn't happened, but, it just … it's a very odd sensation."
Denise O'Brien was in her 20s before she had any explanation. She and her daughter share a rare condition called Alice in Wonderland syndrome, named, of course, after Lewis Carroll's famous childhood fairy tale. Just think of the strange illusions experienced by Alice in the book. (CLICK HERE for more information about Alice in Wonderland syndrome).
In "Alice's Adventures in Wonderland," Alice describes growing so large that she can no longer see her feet: "Now I'm opening out like the largest telescope that ever was. Goodbye, feet." The Mayo Clinic's Dr. David Dotick said that experience is "rather typical … of the patients who describe this sort of distortion of body image."
Dotick is an expert in migraines and their accompanying auras -- those strange alterations in perception or physical sensations that can erupt just before a migraine strikes. Alice in Wonderland syndrome is connected to those devastating headaches that affect 28 million Americans.
"It's not just body image," said Dotick. "Sometimes patients describe mosaic vision, where they see a picture over your face that's fractured and looks like it's in little pieces. Or zoom vision where things seem very, very faraway or things seem … very, very close."
"Some feel as though only part of their body is morphing," he explained. "One patient said it was as if her ear was ballooning out 6 nches."
The syndrome can also cause bizarre alterations of time and space, a perception Katie O'Brien shares with her sister, Molly.
"I'll hear just normal sounds, people talking, driving, music, anything," said Molly. It doesn't get … high-pitched or anything. It's just, everything's just really, really quick."
Dotick says that people who suffer from this syndrome often think they're going crazy. "That's why they tend not to share it. That's why I think it's probably more common than we now recognize," he said.
For all three O'Briens, the Alice in Wonderland auras, which last up to 30 minutes, are a sign a migraine is on the way. Intriguingly, the syndrome can also occur with epilepsy.
"It's sort of a clue, when you have the aura, to go and hide for a while and get rid of it," said Denise.