SHANGHAI - More than 1,000 drug users in Shanghai have undergone an eight-month virtual reality treatment program over the last three years to overcome their addiction.

According to the local judicial department, more than 70 percent of the participants have reduced desire for drugs after undergoing the treatment.

Users wearing a headset see several common drug use scenarios displayed through VR software. The headset is equipped with an infrared eye-tracker that can detect what they are looking at and for how long. If one watches an object for a long time, he or she must be interested in it.

The VR system simulates drug-craving cues in order to collect psychological data to evaluate addicts and help them off drugs. Their biological indicators, such as heart rate and skin conductivity, are recorded at the same time.

Traditional methods to induce drug cravings are mainly fake drugs and pictures of drugs, which look unreal, and addicts' eye movements cannot be recorded accurately, making assessment difficult, said Xu Ding, a senior researcher with Shanghai rehabilitation administration.

"The VR technology can offer an immersive environment, such as a party, a bar or a KTV room, where users can interact with virtual features," Xu said.

Health professionals also use VR to help addicts cut their psychological reliance on drugs.

After inducing drug cravings, VR images automatically switch to scenes showing negative consequences of drug use, such as disease, broken families and suicide, to arouse feelings of discomfort and then aversion to drugs.

"If you see a worm every time you eat an apple, you'll stop wanting apples," said Zhang Chaojing, of Shanghai Qingdong rehabilitation center.

Sometimes the VR system displays natural scenery to help calm addicts, better regulate their emotions and gradually abandon drugs.

"Modern solutions are more scientific," said Xu.

In recent years, Shanghai rehabilitation centers, with local research institutions, have adopted advanced technologies and new methods to help patients free themselves of addictions. A sports-based method has also been used since last year, with addicts guided to control their emotions and actions through exercise habits.

"We hope new technologies can help them improve life skills, get family support and finally return to normal life," Xu said.