The French doctor George Gilles de la Tourette first described the condition – that's often punctuated by expletives - in 1885. But sufferers are only now getting the help they need.
Hawking, screaming and spitting – they are all part of normal conversation with Ben Bruhns. The sudden outbursts are random and uncontrollable. Sometimes, he even jerks a leg forward, involuntarily.
But Bruhns is not acting up or being "weird." The involuntary motions are all tics – and typical for Tourette Syndrome. Ben can't control his tics, or suppress them.
"It's like a spring, winding itself up. And the more it winds itself up, the more it has to release," says Bruhns. "It's like a compulsion, in my head."
Ben Bruhns was diagnosed with Tourette's when he was a child. He's just turned 34 and still suffers from tics. They're totally random and can happen anytime and anywhere – on a tram or at school, on a casual walk, and at the supermarket.
People can find it awkward when they are confronted with Tourette's sufferers in public.
Most would rather avoid contact or interaction with people who shout obscene words.
As a result, Professor Kirsten Müller-Vahl of the Hannover Medical School, says Tourette's sufferers tend to also suffer prejudice.
"About 20 to 30 percent of Tourette's sufferers have what we call coprolalia – they have a compulsion to use curse words. But most don't. There's a theory that there's a region in the brain that's central to obscenities – and that this region is not being suppressed enough. But it's just a theory. We don't really know what's happening," says Müller-Vahl.
But it's clear that there is a disorder in the brain.
In order to make controlled movements, various regions and networks in the brain have to work perfectly together.
With Tourtette's sufferers, these networks tend to be broken, and too much of the neurotransmitter Dopamine gets released.
Professor Jens Kuhn at Cologne's University Clinic describes this as an imbalance. Kuhn treats many Tourette's sufferers, including Ben Bruhns.
"We often treat tics with neuroleptic drugs," says Kuhn. "They're used to control Dopamine release, or rather, they block Dopamine receptors."
When adults suffer from severe tics, however, doctors may suggest deep brain stimulation (DBS) as a treatment. Deep brain stimulation was first developed to treat Parkinson's disease. It helps Parkinson's sufferers control the shakes, and in Tourette's sufferers it helps with the tics.
"The patient has two electrodes implanted in the brain, with a relatively small neuro-surgical operation. And the implants are attached to an impulse generator, which is like a pacemaker, and that's implanted in the chest," says Kuhn.
Ben Bruhns received his brain pacemaker in 2006. And at first, everything seemed to work well.
"Things improved by about 60, 70 or 80 percent. It was great," says Bruhns. "But then I fell on my head and the probes moved. I've had them implanted another three times since then. It's okay today. I've learned to be quite happy with a 50 percent improvement."
Ben prefers to stay at home because he gets stressed when he's with people, and that is when the tics are at their worst.
"At school, they used to call me 'spastic' or 'idiot' and that obviously had an effect on me. They always called me 'spastic', and threatened to beat me up after school," Bruhns says.
In 70 percent of Tourette's cases, the symptoms disappear when sufferers enter adulthood.
Ben Bruhns still has his tics.
When he was younger, he had wanted to train as a retail salesman, but he was bullied repeatedly, and dropped out.
In March, he wants to try again. He's managed to find an apprenticeship with a company that makes golf clubs - despite his having Tourette's.
And this time, he hopes he'll stay.