Do you know why we get goosebumps?

Watching a horror movie gives many of you a chill down your spine. Some of you may even experience goosebumps. Well, the human body has its own set of unexplained quirks. Otherwise, why do we see our eyelids twitching randomly times? Or, why does our body jerk just before falling asleep? Goosebumps are one among these odd body signals that biologists are trying to find an explanation to. We get them while we feel cold or experience an extreme emotion. Actually, the hair of our arms, legs or torso stands upright as the muscles at the base of the hair follicles contract due to a stimulus like cold, fear or any other intense state of mind. Goosebumps are also known as goose flesh and goose pimples. However, the medical term is ‘cutis anserine’ where ‘cutis’ means skin and ‘anser’ means goose (as the texture of the skin is very similar to goose skin).  

The trigger behind goosebumps 
As already mentioned, goosebumps are caused by the contraction of the skin’s tiny muscles which in turn raises the hair roots. But why does this contraction occur in the first place? Well, living beings have complex systems. Your sympathetic nervous system is known for responding to dangerous or stressful situations by regulating the fight-or-flight response. After a sudden stimulus, the system induces an involuntary (one which you cannot control) reaction in skin muscles. We observe similar reactions in the animal kingdom too. For example, you might have seen a porcupine push out its sharp spines when it senses danger. This makes the porcupine appear larger in size, making the enemy pause before attacking. These kinds of responses are linked to the fight-or-flight reaction in our body.  

Goosebumps: More than a simple cold reflex! 
Most of you relate unpleasant situations, such as feeling extremely cold, uncomfortable or terrified, with goosebumps. However, it goes beyond that. The sympathetic nervous system receives an input from a variety of brain regions, including regions responsible for motivation, arousal, and emotion during an episode of goosebumps. You may get them even when listening to music, or seeing an exceptionally moving work of art. Though uncommon, goosebumps can be the symptom of certain brain problems. One of them is called temporal lobe epilepsy, and it can cause brain damage! Goosebumps are also common with withdrawal from heroin or other drugs. 

What function do goosebumps serve? 
When exposed to cold, goosebumps may help you retain heat. Contraction of skin muscles produces heat, just like bigger muscles do! Raised hair follicles tighten skin pores and trap heat. Standing hair traps a layer of air close to the skin and retains body heat.  

It is also possible that goosebumps are an evolutionary phenomenon with no real use to humans now. You may not have any trouble in regulating your body temperature if you do not get them. More in-depth study is required to understand goosebumps better. Recent research links goosebumps to hair follicle (a group of cells that form a pouch-like cavity) regeneration. This insight may provide new strategies for treating baldness or promoting tissue healing!