The purpose of this study is to utilize the radioactive positron emission tomography (PET)
tracer [11C]UCB-J to investigate the effect of repetitive transcranial magnetic stimulation
(rTMS) on synaptic plasticity. UCB-J has been validated as a marker for synaptic density. We
will use this tracer to examine if rTMS leads to changes in synaptic plasticity, specifically
changes in synaptic density, in individuals receiving rTMS for MDD. If rTMS is proven
effective for increasing synaptic plasticity, there is a significant potential of a new
applicable treatment for a variety of diseases that affect brain physiology.