In what type of behavior does an individual adopt the beliefs of a person whom he or she admires ?

This sort of behavior is known as a "mirroring". The individual carefully registers the way the admired person talks, the phrases he uses, his body language, among other traits. He gradually and unconsciously starts to adopt these characteristics as his own. The result is that the individual could end up talking and dressing like the "model" person.

This sort of behavior is normally seen in romantic relationships, as well as on people who strongly admire a celebrity or personality.

In social psychology, mirroring is the behavior when an individual adopts or imitates the gesture, speech, attitudes or believes from another person which is subconsciously. This behavior usually occurs in social situations from close companies like friends or family to artists or public person.  

In biological terms, the “mirror neurons” are activated when an animal acts, then the other is observing and start to performs the same action, in humans occurs the same, we first mimic the movements, action, speech and believes.  

Mirroring is different from conscious imitation, in this latter is done by an effort to copy another person while mirroring is subconsciously done and is often unnoticed.  

So it depends in which situation the person adopts other´s behavior; mirroring has place since childhood and is innate because we all tend to mimic our parents but it is also done in adult life maybe due a psychological terms; mimic also occurs in childhood but without genetic inheritance, and is common in social interactions.  

a punishment or the threat of punishment used to enforce conformity. enforcement of norms or shared rules of conduct that tell people how to act in specific situations. social control. not everyone internalizes all of society's norms, and some people must be motivated by self-fulfillment.