Grandmother Cell
The grandmother cell, sometimes called the "Jennifer Aniston neuron", is a hypothetical neuron that represents a complex but specific concept or object.[1] It activates when a person "sees, hears, or otherwise sensibly discriminates"[2] a specific entity, such as his or her grandmother.
Also mentioned in Gödel, Escher, Bach An Eternal Golden Braid by Douglas R. Hofstadter.