Such integration would have to be limited to low-level microcontrollers tied into musculoneural structures for use in prostheses.
A true AI tied into the central nervous system would be a very dangerous thing, indeed.
It would bring an entirely new angle to John Milton's quote:
"The mind is its own place, and in itself can make a Heaven of Hell; and a Hell of Heaven."
It was exactly that sense of dichotomy that I was trying to capture.
I think I came close.
The character in the short section you read was built artificially from the memories of a dying man. An AI entity using optical microprocessors attended to his construction.
He was born with the memories of a previous life, plus all the advantages that a computer interfacing with every cell in his body might provide.
His intelligence could not be measured, for he had unlimited recall. The disadvantages of his arrangement did not become immediately apparent.