Goosebumps are one of those phenomena that remind us that the separation between human beings and the rest of the animals is, deep down, a mirage, something artificial. Our body is constantly going through hundreds of physiological processes that regulate the way we react to our environment, in theory to better adapt to its variations.
Now… in the case at hand,Why does the skin get gooseflesh And how is this related to our emotions? Let’s see it.
A summary definition of what goosebumps is is the following: it is a condition of the skin in which the body hair stands up, so that since this hair is very fine and short in human beings, it seems that tiny “mountains” appear on its surface. hairs stand on end but normally we pay more attention to the part of the skin that forms the base of these.
The straightening of skin hair, known as piloerection in more formal or scientific contexts, is carried out by small muscle fibers linked to the base of each of the hairs.
Furthermore, this phenomenon does not usually occur in isolation, but is related to changes in states of consciousness and, specifically, in emotional states. In this way, goosebumps have a physiological dimension and another psychological dimension related to emotions. Below we will explore in a little more detail what we know about each of these two facets of having the willies.
It is known that the phenomenon of goosebumps, also known as horripilation, is a vestigial reflex that usually has an adaptive function in mammals in general since this group of animals are characterized by having hair.
The mechanism by which these bumps appear on the skin for a short period of time is as follows.
1. Activation of the sympathetic nervous system
This part of the nervous system is the circuit of nerve cells that intervenes when certain stimuli in the environment make us react to the environment in a state of activation that is more intense than normal. For example, it is the type of contexts in which Attack or flight behavior patterns.
2. Stimulation of the piloerector muscles
These tiny muscle fibers are connected to the sympathetic nervous system and act as a bridge between the latter and the hair follicle, where they are inserted. Upon receiving a signal from one of the nerves, these smooth muscle fibers contract, pulling the hair upward.
3. Changing the hair shaft
In the normal state, by default, body hair is arranged obliquely. That is, falling on one side, instead of being perpendicular to the skin. When it is tense by the piloerector muscle, the trajectory of the hair shaft straightens, so that instead of being almost attached to the skin, it remains pointed. The tension that is generated between the skin that surrounds the base of the hair, on the one hand, and the muscle fibers, on the other, causes a protuberance to appear in the part of the skin through which each hair appears.
As we have seen, goosebumps are something related to vestigial reflexes that come to us through a line of ancestors who did not belong to our species and who probably had much more developed body hair than us. Thus, piloerection could be the difference between having more or fewer offspring, or between surviving or not. Specifically, it has been an advantage for the following reasons
1. Helps insulate from the cold
Piloerection appears among other situations when the body is exposed to the cold, so that the body hair becomes fluffier and creates a wider insulating layer between the skin and the environment. This way, body heat is better preserved.
2. It is associated with situations of danger and reproduction
Another use of goosebumps, at least in our ancestors and in other mammals characterized by having denser and thicker body hair, is to provide the body with a way to appear larger, which is useful in case of let them hang around other potentially dangerous animals that may hesitate to attack or not.
At a level of social adaptation, in addition, the bristling of the hair is a quick way to make others notice that there is danger nearby, since it affects the entire body and, as long as you look in that direction, it is easy to see.
On the other hand, sexual excitement is also capable of causing hair to stand on end, which can be associated with the need to communicate interest or to signal a certain status. The latter is something that in mammals is closely linked to reproduction, especially in the case of males.
In the case of humans, the range of sensations that we can have is more varied than that of most mammals, since our mental processes are very enriched from contextual information articulated from abstract thought.
Therefore, goosebumps can appear in many situations in which a very intense emotion invades us, such as listening to music, being touched by a person, or even listening to a speech or reading a book. In this case, evolutionary usefulness loses its relevance: the hair stand does not have a specific function, it simply exists as a consequence of a process of natural evolution that has led to us (in the case of our evolutionary line).
