Piloerection (or goose bumps) is the reaction of the sympathetic nervous system in which small muscle groups contract. It is a reflex that has evolved in the developmental history of mammals and humans.
What is piloerection?
Piloerection (or goose bumps) is the reaction of the sympathetic nervous system in which small muscle groups contract. Piloerection is a reflex that originally served to regulate the body’s heat. When goose bumps form, the hair follicles of the uppermost layer of the skin are pulled outward and the hair stands out. Goosebumps also appear suddenly when we are excited, frightened or stressed. Goosebumps are most visible on the forearms. However, we get them all over the body, perceiving them only primarily on the extremities. It also appears on legs, neck, chest, neck and buttocks. Music often produces goose bumps, because we are emotionally strongly addressed. Melodies set off many reactions in the brain, because the once heat-insulating reflex was able to transfer to acoustics during evolutionary history. Several theories try to explain the origin of goose bumps. For many scientists, the physiological phenomenon goes back to primal instincts and once served as a defense against hostile threats. Our present, weakly developed hairiness is a genetic remnant of the primeval fur. This had many functions. It served as protection against cold and threats. If the hairs were straight, an air cushion could form in the spaces between them, which acted like an insulating layer. Today, the goose bumps no longer offer us any real protection, because the hair is only sparsely present. However, the reaction still exists. The intensity of a goose bump can be accurately measured thanks to electrical pulses.
Function and task
Goosebumps cause our hair to stand up without warning. It usually happens when we feel cold, intense emotions and illness. Several theories exist about the task of goose bumps, all of which are not without controversy. The most likely is the assumption that goose bumps are a remnant of the fur of our ancestors. Why emotional moments in particular trigger goose bumps is not clear. Theories sound conclusive, but cannot answer all questions. Goosebumps at the highest levels of arousal, for example, do not occur with all elemental emotions. Some scientists suggest that piloerection is a response to frequencies or sequences of sounds made by animal infants seeking their mothers. In the modern world, goose bumps are an instinctive reaction with no particular purpose, it seems. We get goosebumps when we are scared or when we listen to our favorite music. The hair stands up and the skin looks, to exaggerate, like a plucked goose. Each hair on the skin is surrounded by a hair follicle that looks like a tiny mound. Hair follicle and hair bellows make a triangular shape. There are very small muscles on each hair follicle. If these muscles contract, goose bumps occur. An air cushion is created between the erect hairs and the skin. The cushion can better store the body heat and causes a better blood circulation of the epidermis. The contraction of the skin also reduces heat loss. At one time, this bodily function served the purpose of survival. The fact that goose bumps form when we are very afraid is interpreted by some researchers as a display of impertinence towards the enemy. It is possible that goose bumps were a deterrent mechanism. When our ancestors felt threatened, their hair stood up and they got goose bumps. The fluffed fur made them appear more dangerous than they actually were. Also a similar mechanism like the courtship behavior in the animal world could be behind it. With erected fur the prehistoric man looked more splendid and could impress more strongly.
Diseases and ailments
Skin and psyche are closely connected. This strong linkage can be seen even in small reactions. The autonomic nervous system supplies all organs and tissues and is part of the overall nervous system. It influences affects and feelings and controls sadness, joy, anger, aggression and excitement. In addition to goose bumps, the resulting vegetative affects include palpitations, increased blood pressure, paling, blushing, and an increase in breathing rate. Goosebumps are not only responsible for positive feeling.It occurs with colds, shows up with fever and chills. The skin can also make psychological conflicts visible, because the nerve endings reach into the uppermost layer of the skin. Stress in particular is often reflected directly on the skin. As a result of stress, itching, redness, hives or eczema occur. Stress sets a whole chain of reactions in motion and there is an intensive interplay between the immune system, psyche, nerves and hormone system. As a result of the high release of stress hormones, the immune system weakens and inflammatory reactions occur. Many diseases such as neurodermatitis, warts or hair loss can be explained by inflammatory reactions. Skin diseases also unbalance the soul. This is noticeable in psoriasis, the most frequent accompanying symptom of which is depression. Psoriasis often leads to a vicious circle, because those affected feel disfigured and sometimes even disgusted by their own bodies – which is often due to the fact that such a skin condition is socially considered unattractive. As a result, the stress reaction intensifies, and the stress leads to new episodes of the disease. This can lead to complete withdrawal and loneliness. According to recent studies, chronic skin diseases even restrict the quality of life with similar intensity as heart disease, diabetes or cancer.
