Neuralink's Second Successful BCI Implant

Neuralink's Second Successful BCI Implant
Image Source: Neuralink / XBy Thu, 22 Aug 2024 07:48:36 GMT

Neuralink Corp., the brain-computer interface (BCI) company founded by Elon Musk, has recently made significant strides in its mission to connect the human brain with digital devices. The company's latest achievement involves successfully implanting a second brain-computer interface in a human subject, a procedure that marks an important milestone in the ongoing development of this groundbreaking technology.

Neuralink's second implant surgery was deemed successful, with the patient, identified only as Alex, now able to design 3D objects and play video games like Counter-Strike 2. This success follows the challenges faced with the first patient, Noland Arbaugh, whose implant experienced complications when the electrode threads retracted from his brain. To address this, Neuralink implemented several improvements in the second surgery, including reducing brain movement during the procedure and minimizing the gap between the implant and the brain's surface.

These modifications seem to have succeeded, as Alex's implant is performing efficiently, with around 400 out of its 1,024 electrodes actively transmitting brain signals. This information is wirelessly sent to external devices through Bluetooth, allowing Alex to utilize computer-aided design software to craft a personalized mount for his Neuralink charger, demonstrating the technology's practical uses.

Neuralink's brain-computer interface, dubbed "Telepathy," represents the third commercial BCI to undergo long-term human testing. Unlike other BCIs that are either attached to the inside of a cerebral blood vessel or sit atop the brain, Telepathy is unique in that it features a coin-sized electronics hub implanted directly into a hole in the skull. From this hub, 64 flexible threads extend into the brain's cortex, where they record neural activity.

A specialized surgical robot developed by Neuralink is responsible for inserting these threads, a process that takes between 20 to 40 minutes. Each thread is equipped with 16 recording sites, collectively forming 1,024 electrodes that track brain activity. Although the technology is highly advanced, the first implant encountered significant issues—85% of the threads retracted from Arbaugh's brain within a month, diminishing the device's effectiveness. In response, Neuralink engineers swiftly adjusted the recording algorithm to focus on the average activity of neurons around each electrode, which, while offering lower resolution, produced more consistent outcomes.

The improvements made to the surgical process for the second implant included altering the way the hole in the skull was sculpted to prevent air pockets, which had previously dislodged the electrodes. These refinements were crucial in enhancing the implant's stability and ensuring that the flexible electrodes could better withstand the natural movement of the brain.

Despite these advancements, concerns remain about the long-term stability and durability of the implant. The brain is not a static organ; it moves slightly as a person breathes and moves, raising questions about the longevity of the electrode threads that extend from the skull into the brain. Additionally, the materials used in the electrodes will need to be tested over extended periods to ensure they can withstand the environment inside the human body.

Looking ahead, Musk has ambitious plans for Neuralink's technology. He envisions future BCIs that not only restore digital autonomy for individuals with severe movement limitations but also enable humans to achieve symbiosis with artificial intelligence. Such devices could potentially help treat conditions like psychosis, seizures, and memory loss, although these applications present far greater challenges than the current goal of enabling users to control computer cursors