SHANGHAI – Patient No. 1 is a thin man, with a scabby face and bouncy knees. His head, shaved in preparation for surgery, is wrapped in a clean, white cloth.

Years of drug use cost him his wife, his money and his self-respect, before landing him in a Shanghai hospital, facing the surgeon who in 72 hours will drill two holes in his skull and feed electrodes deep into his brain. The hope is that technology will extinguish his addiction with the flip of a switch.

The treatment — deep brain stimulation — has long been used for movement disorders like Parkinson's. Now, the first clinical trial of DBS for methamphetamine addiction is being conducted at Shanghai's Ruijin Hospital, along with parallel trials for opioid addicts. And this man is the very first patient.

The surgery involves implanting a device that acts as a kind of pacemaker for the brain, electrically stimulating targeted areas. While Western attempts to push forward with human trials of DBS for addiction have foundered, China is emerging as a hub for this research.

Scientists in Europe have struggled to recruit patients for similar studies, and ethical, social and scientific questions have made it hard to push forward with this kind of work in the U.S., where the devices can cost $100,000 to implant.

China has a long, if troubled, history of brain surgery on drug addicts. Even today, China's punitive anti-drug laws can force addicts into years of compulsory treatment, including "rehabilitation" through labor. It has a large patient population, government funding and medical device companies ready to pay for research.

There are eight registered DBS clinical trials for drug addiction being conducted in the world, according to a U.S. National Institutes of Health database. Six are in China.

But the suffering wrought by the opioid epidemic may be changing the risk-reward calculus for U.S. doctors and regulators. Now, the experimental surgery is coming to America. In February, the Food and Drug Administration greenlighted a clinical trial in West Virginia of DBS for opioid addicts.

Patient No. 1, who wanted only his surname, Yan, to be published, said doctors told him the surgery wasn't risky. "But I still get nervous," he said. "It's my first time to go on the operating table."

In fact, there are risks. There is a small chance Yan could die of a brain hemorrhage. He could emerge with changes to his personality, seizures, or an infection. And in the end, he may go right back on drugs.

Three of Yan's friends introduced him to meth in a hotel room shortly after the birth of his son in 2011. They told him: Just do it once, you've had your kid, you won't have problems.

Later, he found meth focused his mind, which he directed at one thing: Cards. Every time he smoked, he gambled. And every time he gambled, he lost — all told, around $150,000, he estimated.

His wife divorced him. He rarely saw his son.

Last year his father gave him an ultimatum: back to rehab or brain surgery. "With surgery, I definitely have the chance to get my life back," Yan said.

Before there were brain implants in China, there was brain lesioning. Desperate families of heroin addicts paid thousands of dollars for unproven and risky surgeries in which doctors destroyed small clumps of brain tissue. Brain lesioning quickly became a profit center at some hospitals, but it also left a trail of patients with mood disorders, lost memories and altered sex drives.

In 2004, China's Ministry of Health ordered a halt to brain lesioning for addiction at most hospitals.

DBS builds on that history. But unlike lesioning, which irreversibly kills brain cells, the devices allow brain interventions that are — in theory — reversible. The technology has opened a fresh field of human experimentation globally.

"As doctors we always need to think about the patients," said Dr. Sun Bomin, director of Ruijin Hospital's functional neurosurgery department. "They are human beings. You cannot say, 'Oh, we do not have any help, any treatment for you guys.' "

Sun said he has served as a consultant for two Chinese companies that make deep brain stimulators — SceneRay Corp. and Beijing PINS Medical Co. He has tried to create a center of DBS research, not just for addiction, but also Tourette syndrome, depression and anorexia.

In China, DBS devices can cost less than $25,000. Many patients pay cash.

Some critics believe this surgery should not be allowed.

They argue that such human experiments are premature, and will not address the complex biological, social and psychological factors that drive addiction.

Scientists don't fully understand how DBS works and there is debate about where electrodes should be placed to treat addiction.

There is also skepticism in the global scientific community about the general quality and ethical rigor — particularly around issues like informed consent — of clinical trials done in China.

"It would be fantastic if there were something where we could flip a switch, but it's probably fanciful at this stage," said Adrian Carter, who heads the neuroscience and society group at Monash University in Melbourne. "There's a lot of risks that go with promoting that idea."