Aversives

Denatonium, a very bitter chemical, is sometimes employed as an aversive substance in special nail polishes intended to reduce or discourage nail biting.[1]

In psychology, aversives are unpleasant stimuli that induce changes in behavior via negative reinforcement or positive punishment. By applying an aversive immediately before or after a behavior, the likelihood of the target behavior occurring in the future may be reduced. Aversives can vary from being slightly unpleasant or irritating to physically, psychologically and/or emotionally damaging.

  1. ^ Allen KW (March 1996). "Chronic nailbiting: a controlled comparison of competing response and mild aversion treatments". Behav Res Ther. 34 (3): 269–72. doi:10.1016/0005-7967(95)00078-X. PMID 8881096.