protopathic sensibility

From an evolutionary perspective, it soon became clear to Rivers that the epicritic nervous reaction was the superior, as it suppressed and abolished all protopathic sensibility.

Head and Rivers noted that the thrill evoked by aesthetic pleasure is "accompanied by the erection of hairs" and they noted that this reaction was no greater in the area of skin with protopathic sensibility than it was in the area of the more evolved epicritic, making it a purely psychologically based phenomena.