LessWrong user 天河何处 proposed transferring brain functions to a silicon system piece by piece
LessWrong user 天河何处 proposed transferring brain functions to a silicon system piece by piece
On August 2, LessWrong user 天河何处 published an essay on digital immortality. The author proposes connecting a computing system to the biological brain, using both substrates together for an extended period, and gradually transferring brain functions to the new system.
A conventional digital copy creates two versions. One remains in the original body, while the other runs on a computer with the same memories and habits. The author argues that this means the copy does not continue the original person's experience.
The author defines a person as a “logically continuous experience”: “logical continuity makes you one consciousness, while a break creates two separate consciousnesses.” This leads to the “Ship of Theseus method,” in which memories, experiences, and decision making move to the new substrate piece by piece while the old one is still functioning.
In the author's proposed system, a bidirectional neural interface reads signals from the brain and sends signals back to it. The interface connects the brain to a silicon system. That system synchronizes memories, maps brain functions, initially assists with specific computations, and then assumes an increasing share of those functions. In the author's model, after the biological brain stops functioning, the computational component continues memory, perception, and decision making in a mechanical or biomimetic body.
Two elements of this system have already been used for specific tasks. In a 2021 study, one person with tetraplegia controlled a robotic arm using signals from the motor cortex and received tactile information through stimulation of the sensory cortex. In a 2023 study, Francis Willett's group decoded attempted speech from a participant with ALS using signals recorded by intracortical microelectrodes, reaching a rate of 62 words per minute.
These experiments demonstrate the two operations required by the author's proposal: reading neural signals and transmitting sensory information to the brain. The proposed path requires the computational component to join the shared process before the biological component stops functioning. At the end of the essay, the author asks who should decide whether a person is connected to the interface, how much authority each party should have, and what rights and restrictions would apply after digital immortality.