Using rTMS to enhance social cognition in people with psychosis

In people with psychosis, deficits in social cognition are responsible for a large proportion of the functional disability associated with illness. In a previous study, we found that social cognitive performance is comprised of two subcomponents: 1) a ‘lower-level’ factor reflecting basic emotion detection skills and 2) a ‘higher- level’ factor reflecting higher social cognitive functions referred to as the ‘mentalizing’ factor. The mentalizing factor predicted functional outcome and fully mediated the relationship between neurocognition and social function. Therefore, the mentalizing factor appears to play a major role in determining functioning in people with psychosis. We propose a 4-week (20 session), double-blind, randomized clinical trial in 100 people with early phase psychosis to examine if repetitive transcranial magnetic stimulation, a non-invasive neuromodulatory technique, improves social cognitive performance. We hypothesize that stimulation of the dorsomedial prefrontal cortex - a key node of the mentalizing network - will alter network functional connectivity in people with psychosis and improve social cognitive performance. Neuroimaging will occur at baseline, at 4 weeks and 6 months after treatment. The primary outcome measure will be social cognitive performance, and the secondary outcome measures will include changes in within-mentalizing network functional connectivity and in long-term social functioning.