The anatomy of obsession

A new study sheds light on the specific characteristics of people with obsessive-compulsive disorder. Who hasn't had a thought they can't get out of their mind? Or had a random or inappropriate idea pop into their head? Or felt compelled to double-check and triple-check that the front door is locked? Such intrusive thoughts are normal. Typically they go away and we go about our lives. But for some people, intrusive thoughts can become uncontrollable, persistent and invasive, and so they may try to alleviate them through compulsive rituals: repeatedly washing their hands, for instance, if they fear being contaminated from touching surfaces like doors and countertops. It's at this point that we say the person has obsessive-compulsive disorder, or OCD. But how exactly do the obsessive thoughts of people with OCD differ from the more garden-variety intrusive thoughts we all experience from time to time? This is the question Jean-Sébastien Audet set out to answer in his Ph.D. under the supervision of Frederick Aardema , a professor in the Department of Psychiatry and Addiction at Université de Montréal.