By KATIE MOISSE, ABC News
Brian Kearney was an angry teenager.
"There were lots of holes in my bedroom wall," said 21-year-old Kearney, recalling the "superhuman strength" that sent his VCR clear across the room. "I would say I was a little on edge."
For Kearney, who also struggled with an eating disorder in his teens, anger was a way release the pressure of high school.
"I didn't develop appropriate coping mechanisms," Kearney said.
Nearly two-thirds of American teenagers admit to having "anger attacks" that involve destroying property, threatening violence or engaging in violence, a new study found. And one in 12 has intermittent explosive disorder, characterized by chronic, uncontrollable fits of rage.
"It's an enormous problem that mental health professionals have not taken seriously," said Ronald Kessler, a psychiatric epidemiologist at Harvard Medical School in Boston and lead author of the study, published Monday in the journal Archives of General Psychiatry. "I think it's clear from this study that needs to change."
Kessler describes intermittent explosive disorder, dubbed IED, as the mirror image of panic disorder.
"Without a really good reason, people all of a sudden feel very fearful, or very angry, and do something excessive," he said. "It's either fight or flight."
For Kearney, one wrong look could trigger a "vicious" reaction.
"I can't explain how I felt when I was in one of those fits of rage," he said. "It's almost like I would black out."
Kessler said Kearney's situation is too common to ignore.
"One in 12 kids has this problem. And people very often continue to have this problem into adulthood, affecting their education, jobs and marriages," he said. "Not to mention the criminal implications."
Although IED is listed in the American Psychiatric Association's Diagnostic and Statistical Manual, its cause - and how best to treat it - remain unknown.
"It bears studying, because what we currently know remains speculative," said Dr. Bela Sood, chair of child and adolescent psychiatry at VCU Medical Center in Richmond, Va.
Sood said IED can be hard for patients - and their parents - to handle.
"During an episode, a person goes from zero to 60," she said. "Afterward they often feel remorseful, but the deed is done."
Kearney said he would apologize to his parents after an attack but admitted the anger took a heavy toll.
"It definitely affected our relationship," he said. "But in the end I'm closer to them than I ever was."
Kearney, now a junior at Rowan University in Glassboro, N.J., patched up his relationships - and the holes in his wall - and left his troubled teenage years behind. He credits talk therapy for his victory over anger, as well as Xanax that helps quell his anxiety.
"Everything I've gone through has shaped me into the person I am today," he said. "And I think I'm a pretty good person."