Passage A

In music, a certain complexity of sounds can be expected to have a positive effect on the listener. A single, pure tone is not that interesting to explore; a measure of intricacy is required to excite human curiosity. Sounds that are too complex or disorganized, however, tend to be overwhelming. We prefer some sort of coherence, a principle that connects the various sounds and makes them comprehensible.

In this respect, music is like human language. Single sounds are in most cases not sufficient to convey meaning in speech, whereas when put together in a sequence they form words and sentences. Likewise, if the tones in music are not perceived to be tied together sequentially or rhythmically—for example, in what is commonly called melody—listeners are less likely to feel any emotional connection or to show appreciation.

Certain music can also have a relaxing effect. The fact that such music tends to be continuous and rhythmical suggests a possible explanation for this effect. In a natural environment, danger tends to be accompanied by sudden, unexpected sounds. Thus, a background of constant noise suggests peaceful conditions; discontinuous sounds demand more attention. Even soft discontinuous sounds that we consciously realize do not signal danger can be disturbing—for example, the erratic dripping of a leaky tap. A continuous sound, particularly one that is judged to be safe, relaxes the brain.

Passage B

There are certain elements within music, such as a change of melodic line or rhythm, that create expectations about the future development of the music. The expectation the listener has about the further course of musical events is a key determinant for the experience of "musical emotions." Music creates expectations that, if not immediately satisfied, create tension. Emotion is experienced in relation to the buildup and release of tension. The more elaborate the buildup of tension, the more intense the emotions that will be experienced. When resolution occurs, relaxation follows.

The interruption of the expected musical course, depending on one's personal involvement, causes the search for an explanation. This results from a "mismatch" between one's musical expectation and the actual course of the music. Negative emotions will be the result of an extreme mismatch between expectations and experience. Positive emotions result if the converse happens.

When we listen to music, we take into account factors such as the complexity and novelty of the music. The degree to which the music sounds familiar determines whether the music is experienced as pleasurable or uncomfortable. The pleasure experienced is minimal when the music is entirely new to the listener, increases with increasing familiarity, and decreases again when the music is totally known. Musical preference is based on one's desire to maintain a constant level of certain preferable emotions. As such, a trained listener will have a greater preference for complex melodies than will a naive listener, as the threshold for experiencing emotion is higher.