Arrector pili muscle

Arrector Pili Muscle

Arrector pili muscle (labeled as "Muscles of hair follicles")

The Arrector pili muscle is a small, involuntary muscle in the base of the hair follicle that is responsible for 'goosebumps'. The muscle is a component of the pilosebaceous unit, which includes the hair follicle, hair shaft, and sebaceous gland.

Structure[edit | edit source]

The arrector pili muscle is a tiny muscle that attaches to the base of a hair follicle on one end and to dermal tissue on the other end. When the muscle contracts, it causes the hair to stand up which also produces a bulge of skin known as 'goosebumps'.

Function[edit | edit source]

The primary function of the arrector pili muscle is to regulate hair follicle positioning and sebum secretion. The muscle contraction can also create heat when the body is cold, which can cause the hair to stand up and trap more heat near the body.

Clinical significance[edit | edit source]

Abnormalities or damage to the arrector pili muscle can lead to conditions such as alopecia, or hair loss. Additionally, an overactive arrector pili muscle can lead to excessive production of sebum, leading to skin conditions such as acne.