In people with OCD, actions are at odds with beliefs

UCL researchers have devised a mathematical model to understand what causes obsessive-compulsive disorder (OCD), a set of repeated behaviours deriving from an underlying brain dysfunction that is not yet well understood. In the study, published in Neuron , they found that people with OCD develop an internal, accurate sense of how things work but do not use it to guide behaviour. "This study shows that the actions of people with OCD often don't take into account what they've already learned," said Dr Benedetto De Martino (UCL Institute of Cognitive Neuroscience), the senior author of the paper that was led by graduate students Matilde Vaghi and Fabrice Luyckx. The researchers were able to measure the degree to which beliefs and action were dissociated from one another, and they found that the degree of uncoupling could predict the severity of OCD symptoms. "This was very surprising to me," Dr De Martino added. "It's the first time anyone has been able to calculate the degree of dissociation and show that it correlates with the severity of the disease." Dr De Martino's lab, the Brain Decision Modelling Laboratory, is focused on developing a mechanistic understanding of the connection between confidence and action. Specifically, his group looks at how certainty guides the decisions that we make.