stoic is one or just plain cold.
The word emotion is a noun that means a mental state. Some synonyms for emotion are responsiveness, gut reaction, and affect.
The Yiddish word for being overcome by emotion is "kvell," which typically refers to bursting with pride, joy, or heartfelt emotion.
aloof
glee
Bursting
Motivation is a word used to describe the want or need to do something. The word emotion means the acts or feelings after something happens.
If its an angry outburt, the would be Tirade.
The word emotion is a noun. Words that describe emotions (happy, sad, angry) are adjectives.
Apathetic. It means "to show little or no emotion".
no emotion
You could use the words, Shy, Secluded or Private(:
Negative - irate means very angry... a negative emotion.