The general adaptation syndrome (GAS) coined by Hans Seyle refers to the expected ways in which our body responds to stress. The GAS has various phases or stages. Here we will be focusing on the alarm phase, where our fight-or-flight response becomes activated when we experience stress.This can involve a pounding heart, shallow respiration, dilated pupils etc.
In this given situation, when you are fearful because you think the police is making you pullover, when your heart starts racing, you exhibit behavior associated with the alarm phase of the general adaptation syndrome.