Positronic link

From Memory Alpha, the free Star Trek reference

Positronic links or fibers are an integral part of Data's positronic brain. Their function is similar to the neural pathways in a humanoid body.

In 2368, some of Data's positronic links were severed, shutting his cortex processor off from the rest of his body and leading to a coma-like state. (TNG: "The Game")