“Why are there always so many damn socks in the laundry?”

William Doan’s wife asked him that question 10 years after they got married. He laughs when he remembers it. There were, and remain, so many damn socks in their laundry because when William Doan wakes up in the morning he puts on two pairs.

“I had to sort of fess up at this point,” he said, “and she was like, ‘really?'”

Doan, at 57, has lived much of his life with a diagnosis of obsessive-compulsive disorder, or OCD, as well as an anxiety disorder. He’s an artist and professor of theater at Penn State University.

In pop culture, OCD is often used as a kind of shorthand for fastidiousness. Every source I spoke with for this story quoted the casual diss Oh, you’re so OCD!  that sometimes gets lobbed at neat freaks (or that neat freaks self-deprecatingly aim at themselves.)

But real-life OCD has a specific, straightforward meaning. People who have it experience obsessions and compulsions that feed each other in recursive, hard-to-escape loops.

Wayne Goodman, chair of the department of psychiatry at the Icahn School of Medicine at Mt. Sinai hospital in New York City, explained what obsessions and compulsions are.

“Obsessions are always unpleasant thoughts, or unwanted images, or unwanted impulses. They’re not in any way pleasurable.”

A child might imagine again and again their parents killed in a plane crash. A religious person might feel bombarded with blasphemous urges. Someone else might fear toxins or pathogens that could invade their body.

So they develop compulsions, rituals they act out that offer temporary relief from the obsessions. The connection between the obsessions and compulsions may be difficult for people who haven’t experienced them to understand.

“There are things like hand washing, doing things over and over again, checking and checking,” he said. “But sometimes they can be much more covert. They can be things you do in your head, that nobody else is aware of, to try to neutralize a disturbing thought or unwanted impulse.”

(Interestingly, it’s not actually clear that obsessions arise first and lead to compulsions. There’s a body of research that suggests the reverse. Young children with OCD tend to display compulsions before they can articulate obsessions.)

That said, OCD isn’t about delusion or psychosis, where people can’t distinguish reality from their illness. Goodman said, “Patients with OCD in general have very good insight. They recognize that the thoughts they’re experiencing, although intrusive, are from their own brain.”

Goodman’s description tracks with Doan’s experience. “It’s completely irrational,” he said. “I don’t even reflect on it or try to figure it out anymore. I just know when I get dressed in the morning I’ve got to put on two pairs of socks. It’s part of how I have to begin my day. I have been traveling where I have gone and bought clean socks because I miscalculate the number of socks I’m going to need.”

It would be a mistake though to imagine OCD as a set of odd, if somewhat difficult to manage, quirks. For people who live with it, OCD becomes part of the texture of their hours and days. When Doan walks, indoors, outdoors, or on the treadmill, he counts his steps: 1 … 2 … 3 … 4 … 1 …. 2 …. 3 …. 4

Other people with OCD may perform small rituals — in their heads or with their bodies — all day. These can be relatively trivial and difficult to notice. I watched a friend throw salt over her shoulder three times before she cooked for more than a year. But before she told me the ritual related to her OCD, I assumed she was just superstitious.

But the compulsions can also be debilitating. Goodman describes patients who end up housebound, unshowered, and with uncut fingernails because they’re avoiding germs in the water and outdoors.

For many people with OCD, the symptoms ebb and flow over the course of their lifetime.

“I can tell when im going to have some insomnia,” Doan said. “Or suddenly I know that because I’ve been rehearsing arguments with people over and over and over again in my head that its like ‘Whoa, you’re letting this get the best of you.'”

Doan said that he feels OCD, along with anxiety, in his body before it translates into a mental experience.

The sensation begins in his chest, where the diaphragm sits and the bones of the rib cage join together. He feels vibrations, and a tightening feeling, and his breathing getting more shallow.

“If I could hear it I feel like it would be like humming. It’s vibratory, that’s the best word I have for it,” he said.

Those vibrations the signs of either a panic attack coming on or a period of heightened symptoms that can last for days.

When that happens, he has a series of coping mechanisms he can engage. He meditates. He goes for long walks. He makes art — some of it is illustrating this article — to express the wordless sensation of the illness.

Sometimes Doan’s wife will notice his symptoms before he does.

“We’ve been married for 33 years. And while she only figured out the socks 10 or so years in, she also just knows my personality. And she is really sensitive to when I might be moving into a phase of heightened anxiety.”

She’ll suggest he go somewhere quiet for a couple days to cope, or go for a long drive, or close himself in his art studio.

“She’s become a wonderful partner in that sense, in that she also senses what might be happening, and she knows what my good coping mechanisms are and she helps to facilitate those.”

Similarly, he said his close collaborators in his theatrical work have a habit of using humor to help break him out of obessive-compulsive loops.

While Doan’s experience may be fairly typical as far as OCD goes, the illness has no single common form. Blair Simpson, a clinician, researcher and professor at the Columbia University Medical Center, said that while OCD may be easy to define, in practice it can be hard to recognize and diagnose. That’s because the symptoms follow certain stereotyped patterns. But any two people with OCD will likely have very different experiences.

Broadly speaking, OCD divides into five categories or “symptom dimensions.”

Some people live with fears of contamination (1) or harm (2). They might worry that something will damage or contaminate their bodies. Or they might fear hurting or infecting their loved ones. These forms of OCD tend to associate with cleansing and checking rituals.

Other people feel compelled to do things “just so” (3). I spoke to one person who feels paralyzed when he can’t figure out which parking spot lies closer to his door at work. Another walks into stores to clutch every garment on her favorite rack until the ritual abates.

Then there are people who struggle with “kept thoughts” (4). These are “immoral” thoughts or urges that contradict the deeply held beliefs of people who live with them, like a religious Jew constantly imagining eating a pig.

And a final group struggles with hoarding (5), although researchers now consider that a somewhat separate disorder.

But even within those categories, no two patients have the exact same experience.

“I’ve seen thousands of patients, but I don’t think I’ve seen the same symptoms replicated more than once,” Simpson said. “You have no idea the range of thoughts or impulses patients have. We have patients who think California is contaminated.”

For that reason, she said many researchers avoid focusing too heavily on the specific ways OCD can manifest. Those vibrations Doan feels are too particular to him to draw any broad conclusions from — though they may represent a type of sensation to which other people with OCD can relate.

Right now, Goodman and Simpson say there are only two proven treatments for OCD.

Medicine can help — specifically “serotonin reuptake inhibitors” (SRIs and SSRIs) like Zoloft, which are also used to treat depression and anxiety.

Psychiatrists don’t actually know exactly why SRIs work for OCD, Goodman said. And for a long time serotonin acted as a kind of red herring. Researchers ran down a blind alley looking for a cause of OCD in the brain’s seratonin system. But they found no answers there.

The other proven treatment for OCD? Exposure therapy, which is a specific type of what psychiatrists call cognitive behavior therapy or CBT.

When Simpson has a patient, she’ll work with them to list the things they fear: their obsessions. Then she’ll work through the list with them, from mildest to most severe. She guides them to encounter their obsessions without letting their rituals kick in.

It’s not easy.

“Initially they get more anxious,” Goodman said of his own patients.

People with OCD work hard to avoid their triggers. One person I spoke with compared them to allergies. The mild ones may resemble a light cat allergy. They might make you uncomfortable if you enter the wrong house. Severe ones can be closer to a bad peanut allergy. You might feel like you’re dying if you bite into the wrong sandwich.

And for CBT to work, Simpson said, the course of treatment should be fast — just a few weeks. That’s a lot of stress in a short period of time.

But even with the best medicine and CBT from an expert psychiatrist, Simpson said, she can only expect to reduce symptoms in most patients. There’s no true cure.

“We see on average about a 40% decrease in severity,” she said. Some patients go into near-total remission, while other may see little to no impact at all.

The researchers I spoke with want treatments for their patients. They hope those methods will emerge from better knowledge of the disease. Right now, they suspect the cause or causes of OCD lie in the big-picture ways different parts of the brain connect with one another. And there are already suspect circuits. But the details remain a mystery.

When they figure out the details, Goodman hopes it will transform her job.

“Ideally, I would have battery of noninvasive tests that look at the brain,” she said, “And I could tailor treatments exactly to what I saw, and then monitor the outcomes to see not only if my patients are feeling better but if the circuit is performing better.”

I asked her how far she thinks we are from that kind of treatment, and she paused for several seconds.

“Further than I would hope. I hope I get there in my lifetime. And if we don’t I hope we get there soon.”

In the meantime, most people with OCD can learn to manage their symptoms.

“I think it’s a significant experience in my life, but not a dominant one,” Doan said. “There are times where it has felt like a dominant one, and that’s when reaching out to a counselor or using my coping mechanisms can help. But you know, I don’t wake up every day frustrated or anxious about these things anymore.”

I asked him if he would flip a switch to turn off his OCD if he could.

“Ten years ago I would have said yes,” he said. “I want to do away with my OCD.”

“But I think the time I’ve spent trying to figure out what to do with it, how to cope with it, how to manage it, how to embrace it, how to laugh about it, and how to let it be part of who I am has brought me to a point where I think a lot of my creative energy comes from that place. I’m not saying if I didn’t have OCD I wouldn’t be able to function as an artist, but I do think a good symbiotic relationship has emerged between my obsessive energy and my drive to make work.”