It is a known fact that music can elicit both physical and emotional responses from its listeners and modify their mood. When asked why they listen to music, most people say it is because of the emotions they feel as a result. These emotions go hand in hand with certain physiological changes, such as dropped heart rate or blood pressure. There are two main criteria when relating emotion to music, and these are valence and arousal.
Valence is the difference between pleasant and unpleasant, positive or negative music (Gordana 1787).
Arousal refers to the activity of the music and whether it is passive music or active music (Gordana 1787).
There are many characteristics of music that help determine if it will elicit positive responses, both emotional and physical. Happy music tends to be loud and staccato with a relatively high pitch and quick tempo (Gordana 1787). Pleasant music characteristically contains consonant chords and activate the orbitofrontal area of the right hemisphere of the brain as well as the area below the corpus callosum. Unpleasant music generally contains dissonant chords, which activate the right parahippocampal gyrus of the brain (Weinberger).
Different acoustic cues in songs can bring out various emotions. Some of these cues are tempo, timbre, volume, articulation, tone, and vibrato. Variations of these cues evoke specific emotions in most people. It is debatable still whether music creates these emotions or if it simply helps listeners recall their own experiences with these emotions.
In addition to acoustic cues, there are also physiological responses that are associated with different emotions. Changes in pulse, blood pressure, and respiration can occur while listening to a song, as a result of the emotional response. These are physiological changes related to stress level. Music is known to decrease stress hormones (Gordana 1788). Music can also bring forth laughter, tears, and chills in the listeners. In fact, music engages the same part of the brain as food, sex, and addictive drugs, the reward circuit (Gaidos). This may also contribute to the popularity and attractiveness of listening to music.
Below is a chart with different acoustic cues in songs and how they create the three most basic emotions: fear, sadness, and happiness (Gordana 1788). Also on the chart is a list of physiological responses to music and whether they relate to fear, sadness, or happiness.