Answer:
a placebo effect.
Explanation:
Placebo effect: It refers to the process in which an individual experiences a benefit or satisfaction after the implementation of a sham treatment or an indolent substance. The substance used in a placebo treatment has no medical effects and includes saline solution, and sugar pills, etc.
It occurs when an individual is given a placebo (sugar pills) but he or she believes in getting a genuine or real treatment and confronts an improvement in the condition. It can occur in day to day life.
Viewers' strange reactions in the question above best illustrates the placebo effect.