What is music? Music is a form of art. Music is the ordering of tones or sounds which produce compositions with unity and continuity. A group of tones or sounds is considered as music when it utilizes five elements: tempo, rhythm, pitch, melody and harmony (Jim Paterson)
What does music do to humans? It affects both psychological and physiological functions, by altering emotions and mood. Now let’s see in more details how it happens.
Music produces psychological effects by engaging the limbic system (a collection of brain structures), which is a centre for emotions, sensations, and feelings. Through the limbic system, music brings the alteration to a whole range of emotional state. So music ‘activates’ limbic system which then activates emotions.
Hormones and neurotransmitters (the chemicals which communicate the signal in the brain) are the physiological chemicals of emotion. Dopamine, beta-endorphins and enkephalins (so-called happiness neurotransmitters/hormones) lead to positive emotions of tranquillity and relaxation. It is believed that music causes the release of these hormones and neurotransmitters to produce physiological effects in human body.
In turn, emotions affect the autonomous nervous system, which regulates the functions of the cardiovascular, respiratory, neuroendocrine, and immune systems of the human body (Carolyn Murrock, Music and Mood).
Now, we have seen how our psychological and physiological responses are interconnected and how their interaction creates the feeling of happiness.
However, it is important to note that not every music makes you happy. Different types of music can induce different emotions and moods (i.e. various psychological responses) and thus target different hormones and neurotransmitters, as a result producing a different physiological response (Rollin McCraty et al, 1998). Psychological and physiological responses together produce a whole experience of a particular state such as happiness, sadness or anything else.
Here is a nice and short article on this topic which you might find interesting to read as well: www.seeker.com