MORGANTOWN, W.Va.—Joe Hilton was inside an MRI machine, wearing a $1 million helmet and goggles showing him pictures of heroin being cooked in a spoon and injected into an arm. 

Doctors behind a glass partition used the MRI images to ensure ultrasound waves from the helmet were correctly aimed at a target in Hilton’s brain a couple of millimeters in size. Then, more than 1,000 probes pulsed ultrasound waves to this area, known as the brain’s reward center.

https://www.wsj.com/health/healthcare/addiction-treatment-ultrasound-brain-stimulation-58d6dec3