It is caused by the contraction of fimbriae muscles.
Hairy muscles are smooth muscles related to hair follicles. It consists of a slender spindle-shaped muscle fiber bundle, one end of which is inserted into the connective tissue sheath at the middle side of the hair follicle to the other end, forming an obtuse angle with the skin surface, so that when the hair muscle contracts, the hair stands upright on the skin surface, and the spindle-shaped muscle cells become elastic hard protein fibers at the end and end, which are inserted into the gaps between muscle cells and fixed to form tendon connections. When the muscles relax, the hair returns to its original position due to the elastic recovery of the surrounding dermis, and the elastic hard protein fibers around the outer hair root sheath are firmly attached to the epidermal cells. In fact, it has less elasticity and greater tension. Stiff hair follicles are inserted at the end of the muscle, but the starting point under the epidermis is not stiff, so when the hairy muscles contract, the skin is distorted, resulting in a goose skin-like appearance.
Hairy muscle activity is dominated by adrenergic sympathetic nerves. When there are mental and emotional changes such as fear, the sympathetic nerve is excited, the adrenaline level rises, the hair muscles contract, and the hair stands upright, that is, the so-called creeps and goose bumps appear.
The ancients often used this idiom to describe people's extreme anger. In addition, in some cartoons, people can often see funny scenes in which their hair and beard stand up like thorns when they are frightened or scared. Although "rushing to the crown with one anger" is somewhat exaggerated and exaggerated, it does have certain scientific truth.
The activity of hair is mainly controlled by the contraction of hair muscle, which is a slender spindle-shaped muscle fiber bundle, one end of which starts from the papillary layer of dermis and the other end is inserted into the connective tissue sheath in the middle of hair follicle.
Unlike skeletal muscle, the activity of hair muscle is not controlled by will at will, but by adrenergic sympathetic nerve. When there are emotional changes such as anger, fear and fright, the sympathetic nerve is excited, the adrenaline level rises, and the hair muscles contract, making the hair stand upright and the hair is the most obvious. In theory, when all the hair stands upright, there is the possibility of "rushing to the crown". But in fact, the hair shaft has high elasticity and flexibility. Even without a hat, due to the weight of the hair itself, the contraction force of the fimbriae muscle is not enough to make the whole hair shaft stand upright, let alone "crown". The ancients only exaggerated the normal contraction of this hair muscle to describe people's extreme anger.
References:
Journal of healthy living