It's one thing to accept that emotions "colour" our lives. As we have seen, there is a lot of contention about just what emotions are. It's just as difficult to identify the functions of emotions. As with the original definition, some researchers seem to focus on the physical while others look more at the psychological.

Emotions seem to serve a number of functions. The extent to which any or all of these is more important than any other is a point of debate. Key functions of emotions seem to include:

Arousal - emotions arouse us to move and take action. This is done through activation of the autonomic nervous system, which causes an increased heart rate, etc…

Motivation - some argue that emotions provide the impetus to direct and sustain behaviour.

Being "frozen" with fear makes the attacker less likely to attack.

Adaptive functions - some argue that emotional responses provide us with adaptive responses that assist us in coping with particular situations. One researcher who has pushed this line is Ledoux. While his study focuses on fear, he suggests that various emotional responses are designed to ensure we respond in appropriate ways in order to ensure our survival. This response is known as the Fight or Flight response and occurs when we are under stress. Fear for example, leads to freezing. Generally if an animal is going to attack it will do so in response to movement. If the target is "frozen", it is less likely to attack. Indeed, a recommendation by Hugh Wirth of the RSPCA on how to respond to a savage dog is to freeze. Fear as in "being afraid" came later in the evolutionary cycle.

Adding colour to our lives - this may not be all that scientific but it does take in the fact that expression of emotions through art, poetry and literature provides us with much that underpins the sense of being human. Along with that, the expression of emotions from day to day with people adds colour too!

Regulating social interactions - identifying the emotions that others are feeling through their facial expressions and body language and tone of voice enables us to work out the way to respond. In some instances we may be attracted to an individual, in others, we may be warned to move away. How we respond to ours and other people's emotion is called Emotional Intelligence.