In a blog post on Wednesday, Neuralink said the failure in the threads resulted in “a net decrease in the number of effective electrodes” and the device had been adjusted to make it more sensitive.
It said the changes had resulted in a “rapid and sustained improvement” in the number of data bits the device can transmit per second, and that it has “now superseded Noland’s initial performance”.
Arbaugh is the first human patient to receive a brain implant, although the device has also been trialled by Neuralink on pigs, sheep and monkeys. In future, it could be used to allow many more paralysed patients to operate computers.
Arbaugh previously used a tablet computer and stylus, which he held in his mouth. The stylus prevented him from talking and could cause sores. After trialling the device, he said he had been able to beat his friends at computer games — something he previously thought would be impossible.
“It’s like a luxury overload. I haven’t been able to do these things in eight years and now I don’t know where to even start allocating my attention,” he said.
On March 20, the company ran a live-streamed demonstration of Arbaugh playing online chess. He said he was able to move the cursor of a computer by imagining where he would like it to go.
Experts at Neuralink have explored the possibility the malfunction was caused by a condition known as pneumocephalus, which involves trapped air in the brain potentially caused by the surgery used to implant the device into Arbaugh’s skull.
It was reported in the Wall Street Journal the company considered removing the device in a procedure known as “explantation”.
Neuralink, which was founded by Musk in 2016, has said it hopes to implant 10 of the chips into patients this year.
The device has been approved by the US Food and Drug Administration despite ethical objections from some experts, and reports of animal cruelty at the company during its earlier trials.
The company admitted some monkeys had died during the early tests, but denied accusations of cruelty.
It said it was “absolutely committed to working with animals in the most humane and ethical way possible”.