There is little debate on the role that language plays in the life of human beings. However, language is but one type of vocalization, and there are interesting discussions happening in scientific circles about human musical expression through voice and, by extension, instrumentation.
Why do we have this ability? What purpose does it serve? What is the role of melody and rhythm among human beings?
As with much research, we start with non-human animals.
Sounds produced by animals are understood to be largely, if not entirely, involuntary, tied directly to emotional centers in the brute brain. The perception of danger, for example, will automatically trigger shrieks of warning. Mating season may similarly stimulate a host of breeding-specific grunts and calls. The emotive and linguistic experience of animals is entirely synthesized (in the language of specialists).
This is not the case with humans. We have been blessed with voluntary control over our vocalizations. This requires a separating of emotions from conceptual thinking and behavior. Through this unique gift of language with its requisite psychic separation, we can talk about a dangerous scenario (a tsunami on the other side of the world, for example) without running for the hills.
While this does confer many advantages to humans, it also leaves us more cerebrally fragmented than our animal counterparts. Comparatively speaking, we are poorly synthesized. Our brains are therefore understood to be more differentiated (more scientific jargon).
Differentiation is a kind of fragmentation. Synthesis is about being whole. Those are key points, so you'll need to remember them.
Scientists recognize the interplay of two "inseparable but opposing needs" (Perlovsky, 2010). We have a need to learn about ourselves and the world around us, and this requires differentiation, a breaking up of the emotive-conceptual-liguistic complex. At the same time, however, we have an intense desire for wholeness, total integration of our psychic and physical selves. We crave synthesis.
This is a bit of a conundrum. In our quest for knowledge, we run the risk of losing ourselves.
The more we learn, the more we question, and the further we get from a simple understanding of who we are and what our place in the universe might be. This can lead to a good deal of existential frustration and an attendant sapping of energy. An interesting historical sidelight to reflect on is the incredible success of "less civilized" groups in completely overrunning more "advanced" populations. Those who live by core beliefs that are, for them, beyond question, have conserved a great deal of energy, and others have suffered for it. We have the example of newly Islamized "barbarous" Arabs destroying the Roman and Persian empires. Centuries later, Mongol shepherds conquered most of the known world. It has been suggested that what the invaders lacked in differentiated knowledge they more than made up for through integration and synthesis. This afforded them a greater concentration of will and this was perhaps a major factor in their success.
God knows best.
Anyhow, in order to repair the fragmentation and potential loss of resolve that comes with language and the acquisition of knowledge, that which is learned must be contextualized. Acquired information must somehow be brought in line with our beliefs and emotive experiences. While there are several adaptive responses available to manage this, music, according to one cognitive theory, is a way of reintegrating ourselves. According to Perlovsky (2010), "Its fundamental role in cultural evolution was maintaining synthesis in the face of increasing differentiation."
Where the spoken word may be incapable of connecting to primal emotional centers, music can bring our unconscious drives to the surface where they can be more fully worked out, on an individual or cultural level. Music is understood, then, to be essentially restorative in its function. Over-emphasis upon our intellect threatens to disintegrate our selves and so we have been gifted with melody and rhythm to reconnect with our primal emotional drivers and reintegrate what we know with what we feel and need.
This tension between differentiation and synthesis is understood to further our cultural development. Experiences lead to questions, inquiry that can threaten the status quo on both personal and societal levels. This internal dissonance generates a need for soothing, a return to wholeness. Music seems to provide a way of clearing out that dissonance by bringing our emotions in line with our discordant intellect. This introduces the possibility of a very important dynamic: our internal state is what generates our music and our music will only reinforce our internal state. New ideas, acquired and processed through linguistic and intellectual centers in the brain are reconciled with the remainder of our consciousness through musical expression. Music is but one way of accomplishing this, but in any case the result is an integrated state that affords the newly synthesized individual a greater concentration of will.
He is unified in himself and therefore irresistible.
That might be taking it too far, but here's a citation and you can come to your own conclusions:
Perlovsky, L. (2010, September 22). Music and emotions. Functions, origins, evolution. SciTopics. Retrieved from http://www.scitopics.com/Music_and_Emotions_Functions_Origins_Evolution.html