Arrector Pili

Arrector Pili Muscle

The arrector pili muscles are small smooth muscles which attach to hair follicles. When these muscles contract, they make your hair stand on end – a phenomenon which may better known to you as “goosebumps”.

These muscles are not under conscious control, but are innervated by the sympathetic component of the autonomic nervous system.

Find out more about the autonomic nervous system in this tutorial.