Closed-Loop Transcranial Alternating Current Stimulation for the Treatment of Major Depressive Disorder: An Open-Label Pilot Study.

Major depressive disorder (MDD) is a leading cause of morbidity and disability with sharply increased prevalence through the COVID-19 pandemic, which was not matched with an increase in treatment options. This treatment gap highlights the urgent need for the development of novel treatment paradigms that are safe, effective, and accessible. Non-invasive stimulation has emerged as a promising network-based treatment approach for targeting the brain networks of depression symptoms with electromagnetic energy. Today’s stimulation paradigms mostly focus on specific spatial networks and are not designed to target the temporal structure of large-scale brain activity, which typically exhibits rhythmic patterns referred to as network oscillations. These oscillations emerge from the synchronous activation of neuronal populations and are pathologically altered in depression and other psychiatric illnesses.