According to Elon Musk, the first human patient has been implanted with a Neuralink brain chip. The procedure was apparently successful, Musk said the patient was “recovering well” the day after the operation.

Neuralink, a company that aims to create a brain-computer interface (brain-computer interfaces), began recruiting human patients for its first clinical trial last fall after receiving the green light from the Food and Drug Administration. Neuralink said at the time that people “who have quadriplegia as a result of cervical spinal cord injury or amyotrophic lateral sclerosis (ALS)” could qualify for the trial. “The original goal of our brain-computer interface is to give people the ability to control a computer cursor or keyboard with just their thoughts,” the company wrote in a statement.

Musk did not share any further details about the procedure or the status of the study. He stated that “initial results show promising detection of neuronal spikes”. Successful implantation of the device into a human patient would be a significant milestone for the company. However, in this context it is important to mention that Neuralink also faces a federal investigation for alleged violations of animal welfare laws.

The US Department of Agriculture (USDA) inspector general is reportedly investigating Neuralink for possible animal abuse during research tests. According to Reuters, internal documents show that company employees expressed concern that the company was rushing animal testing and causing them unnecessary suffering.