In this paper, we sought to understand what are the biological mechanisms of Obsessive-Compulsive Disorders so that we could learn how to be aware of our obsessive-compulsive tendencies. Previous research has found that obsessive-compulsive disorder correlates with brain dysfunctions such as with frontal-parietal communication, brain activity in the right frontal pole, and levels of dopamine. In our first (correlational) study, we tested the strength of these relationships by examining naturalistic daily changes in their variables longitudinally over a one-week period. We measured parietal cortex functioning by performance in the Spatial Cueing Task, frontal cortex functioning by performance in the Berg’s Card Sorting Test, levels of dopamine by number of eye blinks in one minute, and OCD by number of obsessive thoughts and compulsive behaviour in a day. Based on the strength of correlation found between parietal cortex functioning and levels of OCD symptoms in our correlational study, we then conducted a second (experimental) study to test for a causal relationship between these two variables. Over a one-week period, we randomly assigned participants each day to either a high parietal cortex functioning experimental condition or a low parietal cortex functioning control condition and measured the effect this manipulation had upon the levels of OCD symptoms. Data pooled across participants in our correlational study showed significant correlations of levels of OCD symptoms with parietal cortex functioning, but not with frontal cortex functioning or with levels of dopamine. However, the results of our experimental study failed to establish a causal role of the parietal cortex functioning upon levels of OCD symptoms. Therefore, the influences of specific brain structures and neurotransmitters on levels of OCD symptoms remains uncertain.
