Those who easily become angry, excited, passive or resentful when driving or playing may be giving insights into the inside self. (Para. 6)
Meaning: When people are driving a car or playing a game, those people who easily become angry, excited, or accept what is happening without attempting to change it, or easily become upset about something that they think it is unfair may be telling us something useful and valuable about their true nature.
adj. 不满(对 ... 产生反感)