Professor Hank Greely is quoted in this Science article on the “special challenges” neuroscientists face when experimenting with implanted devices. 

In 1980, an 11-year-old boy with cerebral palsy had an electrical stimulator implanted into his cerebellum to treat the involuntary muscle contractions that contorted his body. Once the device was switched on, the boy’s erratic movements calmed.

Now 46, the man still uses the stimulator, but the device is wearing out. The company that developed it has stopped manufacturing the device, and the electrodes used in the original are no longer available, says neurosurgeon Robert Gross of Emory University in Atlanta, who cares for the patient.

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Other fields have also confronted the difficulties of experimenting with implanted devices—cardiologists with pacemakers and endocrinologists with insulin pumps, for example. But Hank Greely, a bioethicist at Stanford University in Palo Alto, California, suggests that neuroscientists face special challenges. “We understand the brain much less than we understand the insulin system or heart rhythms,” he says, adding, “although you can do great damage with other implants, you are rarely going to change, directly at least, the patient’s personality. Even with DBS for Parkinson’s disease, we see patients whose personality and behavior changes dramatically with regard to gambling or to sex.”

Recent failures of several large clinical trials of deep brain stimulation for depression loomed large over the meeting. In the United States, companies or institutions sponsoring research are rarely, if ever, required to pay medical costs that trial subjects incur as a result of their participation, Greely points out. “Many people who work in research ethics, including me, think this is wrong,” he says.