Researchers at China's Harbin Medical University are planning to conduct the first primate head transplants.

After performing roughly 1,000 head transplants on mice since 2013, surgeon Xiaoping Ren said that he wants to use monkeys next.

Ren’s team at Harbin Medical University has done many operations on mice since July 2013. They tested ways to help them survive longer than their record so far of one day after the surgery.

According to Wall Street Journal, the mice have lived as long as a day after the operations.

Now, Dr. Ren plans to turn his surgical skills to monkeys this summer. He hopes to create the first head-transplanted primate.

However, doctors researching in the field of head transplants have slammed the proposal. New York University medical ethics professor Arthur Caplan has labeled the idea as ridiculous.

Head transplantation could open up life-changing possibilities for people with severe disabilities or who have experienced extreme trauma. Paralyzed or quadriplegic patients could regain all of their physical movement.

One neurosurgeon, Sergio Canavero, is vowing to try a human head transplant within two years. The plans are ambitious. However, the very fact that they're even on the table shows how much medical technology has changed in recent years.