Switching Off Severe Depression?

Some people with severe depression fail to respond to treatments with psychoactive drugs. A study, albeit on a single patient at the University of California, suggests that a deep brain stimulation device can offer respite to such patients (https://www.theguardian.com/society/2021/oct/04/woman-successfully-treated-for-depression-with-electrical-brain-implant). The neurally-implanted device can detect patterns of activity in the amygdaloid region of the brain. When patterns are detected that are indicative of a depressive episode, tiny electrical impulses are sent to an adjacent brain region called the ventral stiatum. These impulses disrupt the patterns of activity in the amygdala, restoring the patient's mood to normality. Rather obviously, this approach is quite invasive. It certainly would not be appropriate in every case of severe depression. The changes produced in the studied patient were, however, striking. She clearly thought the device was a 'life-changer'.