After a person has been paralyzed for long enough, he or she may wish they could do simple things that able-bodied people take for granted. For instance, one man with quadriplegia agreed to test a new type of robotic arm so that he could drink a beer on his own.

Thanks to the arm, the man is now indeed able to have a drink at his own pace. Using his mind to control the device, he can also do other things, like grasp objects and play video games, according to one of the researchers behind the test.

There are several types of robotic arm prototypes that users operate with their thoughts. This one uses a different process. Instead of implanting electrodes in the subject’s motor cortex, which creates movement, researchers put nearly 200 implants in the man’s posterior parietal cortex, or PPC. That part of the brain activates the motor cortex, by transmitting the person’s intention to move.

This seemingly subtle difference may make controlling the arm easier, the lead researcher told The Washington Post. Instead of having to concentrate on each step of an action, the man can simply imagine the action as a whole. The system interprets the motions needed to complete that action.

This more intuitive system seems to be easier to learn. The man was able to move the arm within a day of trying.

Besides him, the scientists have operated on three other patients to prepare them to use a robot arm. However, the study’s lead author said that mind-controlled robot limbs are still in the early stages of development.