Through 2020, Elon Musk’s company Neuralink paid $1.4 million to the University of California, Davis, to use its facilities, where experimenters removed portions of monkeys’ skulls to implant electrodes in the animals’ brains related to the development of a “brain-machine interface.” Only in 2022, following a public records lawsuit by the Physicians Committee for Responsible Medicine, did the troubling details of these experiments begin to come to light. The company is still conducting experiments on animals at its facilities in California and Texas.

This is the story of one monkey, “Animal 10.” He was a 7-year-old macaque in January 2018 when he was assigned to the Neuralink project. At the company’s request, Animal 10 received less food so he would be kept hungry during experiments. 

 

 

In April 2018, Neuralink experimenters injected Animal 10 with ketamine and fitted a hard plastic collar tightly around his neck. This collar would remain for more than a year. 

 

 

Neuralink used such collars to make it easy to remove a monkey from his cage with a pole. They would then transfer him to a restraint chair for use in experiments while he is awake and conscious like the monkey in this picture.

 

 

On June 1, UC Davis staff noted that Animal 10 had blood in his cage, on his rump, and at the base of his tail. Staff suspected that the cause was a rectal prolapse.

 

 

On Aug. 27, staff observed that Animal 10 had lesions on his right forearm from self-injurious behavior and picking. This is common in monkeys in labs who suffer severe psychological stress.

 

 

On Sept. 3, staff noted that the lesions on Animal 10’s arms had scabbed over. 

 

 

On Sept. 5, staff observed that Animal 10 now had lesions on his right arm and his left leg. This “trauma” was again thought to be a result of self-mutilation and picking behavior. 

 

 

On Sept. 24, UC Davis staff noted that Animal 10 still had trauma to his left leg from self-mutilation, including a lesion on his ankle and redness. They waited for an assessment from behavioral health staff. 

 

 

On Oct. 15, a veterinarian said that Neuralink’s request that Animal 10 be deprived of food be stopped, likely because of his deteriorating mental and physical health.

 

 

On Oct. 15 and 16, lab staff observed multiple traumas, lesions, and “significant hair loss” on Animal 10’s arm from self-mutilation. He was likely suffering extreme psychological distress while being used in Neuralink experiments.

 

 

Throughout the rest of October and November 2018, there were multiple observations of Animal 10 with significant hair loss, trauma, and wounding from self-mutilation and picking.

 

 

In April 2019, after being used in Neuralink experiments for a year, Animal 10 was still experiencing severe psychological stress, with overgrooming, extreme hair loss, and self-mutilation observed.

 

 

In May, more than a year after he was fitted with a tight plastic collar around his neck, UC Davis and Neuralink finally removed the collar. 

 

 

In August and September, Animal 10 still had lesions from self-picking. He also had kyphosis, which is an irregular curvature of the spine.

 

 

On Dec. 17, staff observed that Animal 10 had liquid stool, another common response in monkeys to extreme stress from the lab environment. They put Animal 10 on probiotics.

 

 

For the rest of the month, staff gave probiotics to Animal 10, but there were still repeated observations of liquid stool in his cage.

 

 

On Aug. 21, 2020, staff again observed that Animal 10 had hair loss and lesions “consistent w/picking” on his shoulder, arm, and both legs.

 

 

On Sept. 8, staff noted that Animal 10 had trauma to his arm, with lesions and surrounding hair loss observed, consistent with picking or self-injurious behavior.

 

 

On Sept. 28, Animal 10 underwent a physical exam and health review in anticipation of being shipped. His history of chronic non-pathological diarrhea and self-picking lesions were noted. Despite that, he was approved for shipment. 

 

 

On Oct. 1, 2020, staff loaded Animal 10 into a crate and shipped to Neuralink’s facility in Fremont, Calif. Nothing more is known about Animal 10 or his ultimate fate at Neuralink’s secretive lab.