Tweaking is most often used by the general public to describe someone exhibiting pronounced symptoms of methamphetamine or amphetamine use, including punding (the repetitive performance of useless tasks), hyperactivity, an inhibited ability to relate socially, lack of appetite, inattention to bodily hygiene, exaggerated fidgeting, formication (the false sense of things crawling on or under the skin), or an incessant desire to fiddle or 'tweak' with objects in their surroundings.