Goosebumps are sometimes called goose flesh or goose pimples. These goosebumps are the small bumps on your skin at the base of hairs that stand up on end whenever you feel scared or get cold. You may also experience goosebumps when you are excited about something. Your brain transmits signals to your skin muscles that make them tense up.
When muscles in your skin that are attached to your hair become erect, the hairs pull your skin up. Your body responds this way unintentionally. Humans and animals may both have this response. Supposedly, they call them goosebumps because your skin resembles the skin of a goose whose feathers have been plucked out.
Looking at it on the surface, the reason why you get goosebumps is because of an emotional occurrence, and of which your body reacts to it. Goosebumps occur because your brain sends a message to your body through your spine whenever you are either feeling cold or having a strong emotion towards a situation or something. You also have goosebumps when you experience fear in a situation. Your skin can also develop this occurrence called goosebumps when you set your eyes on something that looks unpleasant or irritating to you.
Now, when you find yourself in these emotional experiences, the brain will send a message to your body through your spine. When this happens, there are some muscles attached to the skin hair, and they also receive the message sent from the brain, which causes the hair on the skin to stand erect. Then you say you have goosebumps. Having goosebumps is actually an involuntary or reflex action.