Piloerction is the erection or bristling of hairs due to the involuntary contraction of small muscles at the base of hair follicles that occurs as a reflexive response of the sympathetic nervous system especially to cold, shock, fright, or awe.
It can be on the nape of the neck or on the forearms and it is a holdover from animal behaviour such as a cat suddenly frightened by a dog or a cucumber.
The Beatle’s debut single Love Me Do from 1962 or thereabouts – the bent notes they sang were enough to raise the hairs on your neck if you were raised on what came before. In my case, the universe expanded in an instant. Recorded from the radio on a reel-to-reel Telefunken tape recorder.