In this four-year project we propose to test whether the association between distinct patterns of brain connectivity measured with functional magnetic
resonance imaging and symptom profiles (biotype) can be used to personalise a brain stimulation intervention for Obsessive-Compulsive Disorder (OCD).
OCD affects 1-2% of Australians, 25% of whom attempt suicide. Symptoms of OCD are classified according to two major features: obsessions, aggressive
intrusive thoughts and compulsions, ritualistic acts performed to alleviate the distressing thoughts. There is currently no cure for OCD and while
pharmacological and behavioural interventions can mitigate OCD symptoms, over 50% of patients remain clinically symptomatic and highly disabled 40
years after initial treatment. Noninvasive brain stimulation technologies such as transcranial magnetic stimulation (TMS) are exciting emerging techniques to
complement existing therapies. However, the approach to treatment has so far been dominated by trial and error and there is currently no personalisation of
the intervention based on neurophysiological and clinical markers. In the past decade, animal and human work have converged in indicating that symptoms of
OCD are supported by abnormal communication between subcortical and cortical brain regions. Here we propose a study to assess whether an innovative
biotype-based TMS intervention successfully normalises brain connectivity and reduces OCD symptoms compared to non-guided TMS or placebo. This
project represents a necessary step for the translation of new knowledge and methods to modulate brain connectivity using local TMS. Results from this work
will provide strong neurobiological and clinical evidence motivating a large phase III clinical trial assessing the clinical efficacy of the proposed TMS
intervention for OCD. More generally, outcomes from this study will provide the foundations for the next generation of personalised brain stimulation
therapies in psychiatry.