Friday was my fourth treatment. We've maxed out on both sides now so it won't get any worse. The only uncomfortable bit is my jaw moving. On the right side, I snap my teeth. Not much though. If I bit my tongue it would hurt but no more than all the other times in my life I have done so. Ouch! And even though my jaw muscles are being stimulated on both sides, I haven't had any muscle ache after. So far so good.
Since I can't take a photo myself, here is much what my treatment looks like, only the lounge chair I sit in is more comfortable than this looks, and I wear a lycra cap. The cap is marked to make sure that the exact same spot in my brain is stimulated each time.
Below is what the actual instrument looks like, though the one used on me is attached to a stand like in the photo above. My psychiatrist says it puts out 3 Teslas, similar to a standard MRI. The best MRI available uses 7 Teslas.