Symmetry, ordering and arranging compulsive behaviour.

Compulsive ordering and arranging, and a preoccupation with symmetry are features of obsessive-compulsive disorder (OCD) that have not been examined experimentally. Three connected studies were conducted to examine this phenomenon: a self-report measure of this behaviour was developed and validated, participants were asked to engage in tasks designed to assess preferences for order, and to assess the interference of disorderly surroundings in the completion of a stressful activity. The self-report measure has sound psychometric properties and validity. Participants with a strong preference for order were made more anxious by having to complete a difficult task in a disorganized environment. Participants without this preference did not show this effect. The results are discussed in terms of the phenomenology of compulsive ordering and arranging, and its relationships with both OCD and normal human behaviour. It is suggested that compulsive ordering and a drive for symmetry are extreme manifestations of the common preference for order and symmetry.