Understanding OCD

When I was a young student in Saarbrücken, Germany in the early 1960s, I was quite undecided what I should study. I went to many different lectures, with no idea what subject to specialise in. One day my decision was suddenly made for me.

For a psychiatry lecture, which psychologists as well as medical students could attend, the professor had brought along one of his patients who suffered from OCD. The patient impressed me hugely. He spoke in a strikingly rational way about how he was obsessed by an absurdly irrational fear. He was convinced that, if he did not rid himself of germs, there was a real chance that he could infect members of his family through wounds they might have accidentally acquired. It was a monstrous fear that haunted him all his waking hours, and that no amount of washing could rid him of.

Like most people I had thought that being obsessive and compulsive was merely a quirky personality characteristic, and quite a common one. I imagined that I too was a bit obsessive. I can remember that, as a child I sometimes had the urge to touch every fence post, and I am still strongly drawn to straightening picture frames when they hang askew. But that was a long way from the case that I witnessed. It made me realise that OCD is a harrowing mental illness. But this was also very different from what I had imagined mental illness to be. I had observed some schizophrenic patients who were utterly convinced that their irrational thoughts were nothing but the bare truth. By contrast, the patient's account of himself was incredibly rational. His monster had only grown stronger over the years; he knew the cleaning procedures he imposed on himself were hopelessly ineffective and only ever gave him a few moments' relief, yet he could not stop them.

From then on I knew what I wanted to do. I wanted to be a researcher and find out what makes the mind behave in such a strangely contradictory way. How could your own mind keep you in thrall of some unimaginable fear when you knew that the fear was irrational? This was like creating your own nightmare and never being able to escape from it.

I started to read avidly about mental illness and found that the then available methods of treatment, ranging from lobotomy, electroshock, psychoactive drugs to psychoanalysis, were spectacularly unsuccessful. But then, in the psychology department I heard about a new way of treating mental illness that was being developed in London's Maudsley Hospital. I knew I had to go there and learn more about it.

The revolutionary new way was called 'behaviour therapy', and OCD, together with other anxiety disorders, was a showcase for its success. By good fortune I was accepted on a course in what was then called 'abnormal psychology'. I had already decided to do a PhD on OCD, but fate intervened. During my rotation on the course I met children with autism. This diverted my interest from OCD (although autism too is often associated with obsessions and compulsions).

From time to time I have wondered wistfully what progress had been made in our understanding of OCD. This was why I was extremely excited to be asked to present this documentary. It gave me a chance to catch up on new developments and it immediately rekindled my earliest interests in the mind and brain.

One particularly gratifying experience during filming was that I was able to visit Isaac Marks, who had been one of the pioneers of behaviour therapy at the Maudsley when I was a student. It was fascinating to hear him reminisce about his first attempts to apply the insights he had gained from an animal learning experiment he had watched in the US.

Remarkably, later on during the filming, I saw a version of this same experiment being carried out with humans in the brain scanner at Cambridge's Addenbrookes' Hospital. I was also excited to meet David Adams, whose insightful account of his own OCD in his book The Man Who Couldn't Stop is better than any textbook.

I discovered that the leading OCD researchers are on the way to finding the brain abnormality that can explain the cruel tricks that OCD plays on the mind. Trevor Robbins and his group in Cambridge have identified a critical neural circuit, connecting two major brain regions. One is the orbitofrontal cortex, known to be concerned with achieving valued goals. The other is mid-brain region, the basal ganglia. This is known to be associated with our ability to acquire automatic habits. According to Robbins, in the case of OCD the habit system has gained dominance over the goal-directed system, just as it does in drug addiction. It's an ancient system that serves as a precaution against invisible threats, such as contamination and predator attack, but in OCD it seems that this system cannot be turned off. The potential threat is ever present. There is no way to obtain certainty that it has disappeared.

I was also struck by the 'hyper-responsibility' of the patients: their family, even the world at large will be catastrophically affected if they fail to carry out precautionary rituals. Why? I couldn't let go of this question. We know little about how we control our own thoughts. Fortunately, most of us are under the illusion that unwanted thoughts are not caused by us, but by 'our brain'. We can dismiss them, and then we do not feel responsible for them. People with OCD don't have this luxury. The unwanted thoughts intrude on their full consciousness, creating the illusion that they did cause them, and therefore that they are responsible.

By the end of the filming I was convinced that OCD provides an amazing example of how our common understanding of mental illness has gradually changed over the last 50 years. Today we have much more awareness of mental illness and put less blame on those who are affected. Professional help is available. There are also excellent support networks that inform and inspire. Exciting advances are being made about the abnormal functioning of particular brain circuits, but that's only the start. To understand how brain and mind relate to each other is a hugely complex enterprise. We have hardly embarked on it.

- Watch now. Also view the BBC resource.