Neuralink Reveals Cable Withdrawal Problems In First Patient Brain Implant

Noland Arbaugh, Neuralink's first brain implant patient who was paralyzed from the shoulder down due to a diving accident (photo: x @ModdedQuad)

JAKARTA - Neuralink, a company founded by Elon Musk, last week revealed that the tiny cables in the brain of its first patient had shifted from its position. However, according to five people familiar with the matter, the company has been aware of this issue for years.

Neuralink learned from animal testing carried out before obtaining approval from US authorities last year that the cable might be interested, resulting in sensitive electrodes decoding of brain signals being interested, three sources said. However, Neuralink considers the risk to be low enough so there is no need for a redesign, the sources added.

Neuralink is testing this implant to give patients with disabilities the ability to use digital devices just by thinking, a prospect that could help people with spinal cord injuries.

The company last week said small implant cables, which were thinner than human hair, were attracted by the patient's brain in the first human trial, resulting in fewer electrodes that could measure brain signals.

This signal translates into action, such as activating the mouse cursor on the computer screen. The company says it has succeeded in restoring the implant's ability to monitor patient brain signals by making changes including modifying its algorithm to make it more sensitive.

The sources declined to be named because of the confidentiality agreement they signed with the company. Neuralink and its executives did not respond to media reports on this matter.

The US FDA is aware of potential problems with the cable as the company shares animal testing results as part of an app to start human trials, said one source.

The FDA declined to comment on whether they were aware of the matter or its importance. The agency said it would continue to monitor the safety of patients registered in the Neuralink study.

If Neuralink continues trials without a redesign, they could face challenges if more wires are interested and algorithm modifications prove insufficient, said one source. However, redesigning the cable has its own risk. Rescaling the cable in the brain, for example, could cause damage to brain tissue if the cable is detached or if the company needs to remove the device, two sources said.

The company has been trying to design cables in such a way as to facilitate its release, so that implants can be updated along with technological advances, said current employees and former employees.

In January, Neuralink implanted a device in the brain of the first patient, Noland Arbaugh, who was paralyzed from the shoulder down due to a diving accident in 2016. Within weeks of surgery, a number of wires were attracted to the brain," Neuralink said in a blog update last week. The post did not mention any adverse health effects on Arbaugh and did not reveal how many of the 64 device cables were interested or stopped collecting brain data.

So far, the device has allowed Arbaugh to play video games, explore the internet, and move the computer cursor on his laptop just by thinking, according to the company's blog post and video. Neuralink said that as soon as the operation, Arbaugh surpassed the world record for speed controlling the cursor with only a thought.

It is common for medical device companies to look for various design solutions during animal trials and for problems that arise during animal and clinical testing, according to outside researchers and sources who have worked in Neuralink and other medical device companies.

Specialists studying brain implants say moving cable problems can be difficult to overcome, in part because of the mechanism of how the brain moves inside the skull. Robert Lagat, a neurologist at the University of Pittsburgh, described cable movement so quickly after surgery as disappointing but unexpected. In a few days, weeks, months after implants like this, this may be the most vulnerable time," he said.

PIG HEAVING

In 2022, the FDA initially rejected the Neuralink app to start human trials, and raised safety concerns about cables. Neuralink conducted additional animal testing to address those concerns, and the FDA last year gave the company approval to start human testing.

The company found that a number of pigs that were implanted with their devices developed an inflammatory type in the brain called granuloma, which raised concerns among Neuralink researchers that the cable could be the cause. Granuloma is an inflammatory network response that can form around foreign objects or infections.

In at least one case, a pig developed the condition badly. The company's records reviewed by Reuters show that the pig had a fever and had difficulty breathing after surgery. Neuralink researchers did not realize the extent of the problem until they examined the pig's brain after it died.

Inside Neuralink, researchers debated how to fix the issue and started an investigation for months, said sources familiar with the event. "Finally, the company was unable to determine the cause of the granuloma, but concluded that the installed device and cable were not blamed," said one source.