Nervous system

The nervous system was a network of nerves and axons that enabled control of the body.

The Third Doctor speculated that the Nestene creature in Channing's tank was a kind of brain or nervous system, humanly speaking. (TV: Spearhead from Space)

Sutekh said he could shred the Fourth Doctor's nervous system into fibres and draw the pain out for centuries. (TV: Pyramids of Mars)

Mehendri Solon required the head from a species with a central nervous system to complete Morbius' body. (TV: The Brain of Morbius)

The Hoothi infected other creatures, usually having better control over ones with more complex nervous systems. (PROSE: Love and War)

After the Boneless killed Forrest, they performed an exploratory dissection of her nervous system and left a two dimensional print of it on a wall. (TV: Flatline)