Grant: Project Grant

Major depressive disorder (MDD) is a common and disabling condition. Up to one-third of patients with MDD do not respond to standard treatments, such as medication and therapy. Alternative treatments include direct-to-brain interventions, such as repetitive transcranial magnetic stimulation (rTMS). rTMS uses magnetic pulses to stimulate a region of the brain involved in mood. While rTMS is effective for some patients, not all patients benefit. To prevent patients from undergoing an intensive treatment (daily rTMS treatments for ~4 weeks) that will ultimately be ineffective, there is need to determine early on whether patients will benefit from rTMS. This study will examine whether tests assessing speech and eye movements can determine early on whether patients will benefit from rTMS. We focus on speech and eye-tracking markers because they are known to be altered in people with depression and track with symptom improvement. In addition, speech and eye-tracking tasks are inexpensive and easy to complete. Patients with MDD will be tested 4 times: before rTMS, 1-week after rTMS begins, at the end of rTMS (~4 weeks later), and 1-month following treatment. Depressive symptoms will be measured with a depression questionnaire. A non-depressed control group will be tested at single time point. We will test the following hypotheses: (1) Speech and eye-tracking measures will differ between depressed and non-depressed individuals. (2) Speech and eye-tracking measures will be associated with depression severity in patients with depression. (3) Early changes in speech and eye-tracking measures will predict who will benefit from rTMS treatment. If successful, this study will show that speech and eye-tracking patterns can indicate early on whether patients will benefit from rTMS. Such measures could easily be integrated into clinical practice, allowing clinicians to discontinue ineffective treatments more quickly, thereby reducing the burden of illness for patients.