Successful entrepreneur Aaron Harvey was around 13 years old when he experienced his first intrusive thought.

“I was playing basketball and was called to come in. When I went to my room and there was a baby sleeping in there, I had a thought of harming the child,” Harvey told FoxNews.com. “At that age, I thought I was maybe psychotic.”

Harvey was not suffering from psychosis, and he was not schizophrenic. He has a form of obsessive compulsive disorder (OCD), known as Pure Obsessional OCD, commonly referred to as Pure O. The condition involves having unwanted thoughts that repeatedly pop into your head whether you like it or not. But unlike a daydreamer’s reverie, these thoughts or images are often violent and horrific, and for people with OCD, the only way to escape them is by doing mental rituals. These rituals or compulsions tend to take place within a person’s mind, so you won’t see someone with Pure O rinsing their hands a hundred times or counting cracks on the streets.

Dr. Anthony Pinto, a licensed psychologist and director of the Northwell Health OCD Center at the Zucker Hillside Hospital in New York, said examples of mental rituals can be as simple as using special words, images or numbers to neutralize intrusive images. Common examples include when a person reviews reasons for why they aren’t a pedophile or a serial killer, and then mentally repeat reassurances to themselves, like “I would never do that,” or “I love my family,” Pinto said.

“They might use these mental rituals like prayer or counting to neutralize that anxiety or to try to make that anxiety go away as a way to cope,” Pinto who is also on the adjunct faculty at Columbia University Medical Center Department of Psychiatry, told FoxNews.com, “except the more you do them, the more you have to do them to lower your anxiety, you become dependent on them.”

Although the exact cause of Pure O is not fully understood, some experts have associated the disorder with genetics or a biological misfiring in the brain.

"Eighty-five percent of humans in the non-clinical population reports to having these types of associations."

“It’s an oversensitivity of the brain to reacting to signals that ordinarily would not produce an emergency reaction, but in people with OCD it’s misfiring as if there’s a crisis going on,” Dr. Steven Phillipson, a clinical psychologist and director of OCD Online, told FoxNews.com. “Eighty-five percent of humans in the non-clinical population reports to having these types of associations. But with the OCD subset of [the] population, there’s such a pairing of terror that a person becomes manipulated to believe that there must be something wrong with them— there must be a danger if I feel this threatened or that I might be capable of acting in a violent way.”

Intrusive thoughts can manifest over time and typically fall into three categories: sex, religion and violence. Their frequency can vary from patient to patient, but in Harvey’s case, he was having “hundreds and hundreds” per day.

From sacrilegious images of Christ to confusing thoughts about his sexual orientation, Harvey’s mind continued to play tricks on him into adulthood.

“A butcher knife would be out on the table and I had a thought of killing her with the knife."

“It started getting really scary for me when my ex moved in, [when] we were engaged,” Harvey said. “A butcher knife would be out on the table and I had a thought of killing her with the knife. I was so scared that I put the knife away to take away the thought.” Harvey explained his unwelcome thoughts eventually led him and his fiancée to begin dining out instead of cooking.

Often, Pure O patients’ nightmare-like thoughts can feel like one continual panic attack.

“Before your logical mind can say, ‘This is not a threat,’ you've already been completely overwhelmed with anxiety throughout your entire body,” Harvey said. “It kind of feels like your stomach is being cut up.”

Harvey never confided in anyone about his evil thoughts. He lived in silence and suffered alone for more than 20 years, a decision that almost brought him to suicide, he said.

“The OCD had really gotten to me at that point, and there was a lot of suicide ideation,” Harvey said. “There was a lot of picking dates and doing dangerous things, which ultimately led me to that first Google search to try to figure out what was going on before I really did something harmful.”

Those Google search results helped illuminate the condition Harvey had been coping with for nearly his entire life: Pure O. But with limited online resources, finding the right type of treatment was an experiment on its own. Mental health professionals continue to debate which therapy remains the most appropriate.

“Traditional therapy, like analysis, is not only ineffective but highly detrimental,” Phillipson said. ”To look into the nature of the thoughts as if there’s some underlying issue going on— or an analyst saying, ‘Oh, if you have thoughts about harming your child, we need to look deeper into your underlining anger issues’— that’s really not what’s going on. They’re still trying to see the thoughts as the problem, which they’re not.”

Cognitive therapy is another common form of treatment that Phillipson advises against. In this type of therapy, therapists try to help patients identify the rational reason for their thoughts. Although the patient might find comfort in a doctor telling them their thoughts are irrational, this approach could make the patient dependent on the therapist’s measurement of what is rational and what is not, Phillipson explained.

Instead of encouraging a greater examination of the intrusive thoughts, Philipson said patients need to train their brains to accept them. He suggested exposure response prevention therapy (ERP), which aims to help patients manage obsessive behaviors.

In ERP, patients voluntarily recall their feared, intrusive thoughts so they can proactively challenge the mental rituals they’ve become accustomed to using to relieve any accompanying anxiety or terror.

 “When patients engage in this treatment in a very aggressive way the brain very quickly recognizes that these ideas and this terror experience is no longer necessary to protect so it naturally shuts it down,” Phillipson said.

A study published in the December issue of the Journal of Clinical Psychiatry found 53 percent of patients who had not responded to multiple trials of medication and followed ERP saw their OCD symptoms improve.

Harvey often ruminated about running someone over with his car. He wasn’t aware that one of his mental rituals was putting the car in park whenever he stopped at a stoplight, for the fear of stepping on the gas and killing someone. But after months in ERP therapy, he learned how to react without anxiety. 

“So my exposure is to leave the car in drive, and by leaving it in drive, I’m accepting the fact that my foot might fly over to the other side and run someone over, and as a result I’m devaluing that thought,” Harvey said.

Today, Harvey is breaking his silence and has launched IntrusiveThoughts.org, a website dedicated to educating and empowering OCD sufferers. Harvey’s mission to raise awareness of the disorder is personal. He said he doesn’t want kids to suffer alone like he did.

“I could have lived a much different life over the last 20 years— a much healthier and happier life,” Harvey said, “and the only way to do that is to empower sufferers with the condition to actually start talking about them.”

Some studies estimate that up to 1 out of 5 children experience a mental disorder in a given year.

“We need to find ways to get information out about the different forms for OCD [and] that it’s not just the washing of hands— the more stereotypical example of it,” Pinto said. “We need to increase the awareness on the different ways OCD can manifest in the first-line areas where these patients might be presenting symptoms— through the school and primary care physicians.”

Pure O, like the rest of OCD subtypes, is a chronic condition. There is no cure or easy fix, but patients can respond well to treatments and experience periods of remission.

“The goal isn’t for the thoughts to be gone. The goal is for the thoughts to be meaningless and ineffective,” Phillipson said. “Recovery is a state where a person’s brain might produce these associations rather than 40 to 50 times a day, to possibly twice a day, sometimes twice a week.”

For more information visit IntrusiveThoughts.org.