The Pleasure Instinct: Why We Crave Adventure, Chocolate, Pheromones, and Music (14 page)

—William Shakespeare,
Much Ado about Nothing

—Charles Darwin,
The Descent of Man

 

 

 

Several years ago I volunteered at a behavioral clinic and worked with a group of fourteen adolescents who were diagnosed with attention-deficit-hyperactivity disorder (ADHD). It was an amazing thing to see such large differences in symptoms among teens with the same diagnosis and even within the same individual from day to day. We had our share of students who were chock full of what most would consider normal childhood energy, along with others who were clearly different in that their activity levels seemed unending in practically every context.

At our clinical staff meeting one Monday morning, a new intern raised the possibility of adding music therapy to our group sessions. While some of us, I’m sure, were picturing a guitar and perhaps a few harmonicas, she went on to tell us about her friend who teaches African drumming. She argued passionately that kids with ADHD respond well to drum sessions because they promote group cooperation and turn-taking.Within two weeks, we had fifteen beautiful instruments—ten
kpanlogos
, with their warm, earthy bass tones, and five
djembes
, offering a high, snappy timbre.

The drums came complete with a colorful music therapist fresh out of UC Berkeley, who visited us every Thursday afternoon. Joachin began a typical drum session by gathering all the students into a circle and starting a very simple rhythm consisting of one beat sounded roughly every second—a “heartbeat.” In the first few weeks, just getting all fourteen students to sit in their chairs at the same time was a genuine accomplishment, but by the end of the first month they began to look forward to each session, and the changes in our little community were palpable. At some point during the fifth session, I remember feeling a deep sense of pride at how fast our circle had joined into a synchronized beat that particular day.

Joachin gradually introduced more complicated rhythms that were to be played on top of the heartbeat. Each student had a rhythm to maintain in concert with the entire circle—some had to play
menjani
, while others had to play
aconcon
or something else, and this varied from session to session.Above all, there was no room for solo performances in the circle, and whenever the group’s overall rhythm broke down, we would start over amid sighs of frustration.Toward the end of the third month a noticeable improvement in our collective sound became obvious.The sessions began to take on a true communal feel, and at times the group’s two or three main rhythms were so synchronized that the sound became almost hypnotic. During these periods I often lost myself in the moment, imagining the millions of other drum circles that have played across time and culture—humans of all kinds joining and celebrating nature’s periodicity. One minute I’m drumming with students in a therapeutic residence, the next I’m part of a tribal clan of early hominids living along the Rift Valley. Perhaps we’re drumming in preparation for a hunt or to celebrate the arrival of a newborn or a marriage.

Ancient drums have been discovered in almost every part of the world. Their earliest appearance in the archaeological record dates back to about 6000 B.C., excavated from Neolithic Era sites in northern Africa, the Middle East, and South America. Ceremonial drums have been found in these regions, along with wall markings depicting their use in various aspects of social and religious life. Other percussive and even flute-like instruments have been unearthed at
Homo sapiens
sites throughout Europe and Asia dating as far back as a hundred thousand years. And the music wasn’t limited to modern humans—it appears that Neanderthals made music as well. Archaeologists excavating a cave near Idrija in northwestern Slovenia recently found a bear’s polished thighbone with four artificial holes drilled into it that were aligned in a straight line on one side. Although we don’t have any way of knowing if this sixty-thousand-year-old object was ever used to make sounds or even music, very similar “bone flutes” have been discovered at
Homo sapiens
sites and estimated to be forty thousand to eighty thousand years old.

The rule is very simple in modern cultures across the world and throughout all of recorded history: wherever there are humans, there is music. No recorded human culture—whether extinct or extant—has ever been without music production. Although what passed for a melody in ancient China undoubtedly differs from, say, what a twenty-first-century European might find entertaining, all humans have a faculty for producing and enjoying music. Indeed, given the omnipresence of music production and enjoyment across human civilizations, some researchers consider musicality to be an evolutionary adaptation, perhaps akin to language. But unlike language, which is used to communicate our thoughts to others, music has no clear-cut survival or reproductive consequences. So the question remains:What is the adaptive function of music?

There are generally three schools of thought on the origins of music. The first group views music as an interesting, albeit evolutionarily irrelevant artifact of our sophisticated brains—a form of “auditory cheesecake.” The basic idea is that humans evolved a set of sophisticated cognitive, motor, and perceptual skills that have clear survival and/or reproductive value, and the expression of these skills led naturally to the emergence of other by-product abilities, such as art appreciation and musicality. The cheesecake view is overwhelmingly the most popular in mainstream psychological thinking today.

A second view is that music has real survival value and has been forged by the same principles of natural selection that have shaped other cognitive abilities such as binocularity, color vision, sound localization, and so forth. A wide range of suggestions for the function of music has been made, most having to do with its ability to bond the social group through coordinating action and ritual. Undoubtedly, music can have a profound influence on the behaviors and emotions of large groups of people—if you need to be convinced, simply visit a local nightclub or ballpark. This view, however, has its problems because it depends on the rather untenable position of invoking group selection to account for the evolution of musicality—a mechanism that has never proven convincing to scholars of mammalian evolution.

Finally, a third school of thought argues that music evolved primarily through mechanisms of sexual selection rather than natural selection. The chief difference between the two, of course, is that natural selection fosters adaptations that increase an organism’s likelihood of survival, while sexual selection fosters adaptations that increase the likelihood of successful mating and reproduction. Both mechanisms impact the ultimate scorecard of evolution—how well an organism passes on its genes—yet the adaptations that emerge can often be at odds with one another. For instance, the size and color vibrancy of the peacock’s tail is an important variable in reproductive success. Peahens are attracted to males with the largest and most colorful displays. At the same time, however, this conspicuousness puts “handsome” peacocks at a survival disadvantage from a natural selection viewpoint because they are easier to spot by predators, and vibrant, cumbersome tails make them less able to evade an attack. Indeed, adaptations driven by sexual selection often emerge
because
they handicap an organism’s survival in some way that makes it easier to assess its true fitness. In this example, the fitness cost of having a large and colorful tail makes the peacock an easy target. Those males who have the most conspicuous tails are truly the fittest—the thinking goes—because they can afford both the metabolic cost of growing a large tail and the survival cost associated with attracting the attention of predators. In this context, music is seen as just another ornate animal display designed to get the attention of the opposite sex. The proponents of this view argue that music production is a reliable fitness indicator because it signals an ability to maintain a high degree of skill at the cost of diverting energy, attention, and time away from basic survival behaviors.

Each of these perspectives on the origins of human musicality is based on distinct mechanisms and therefore has unique implications for our relationship with music and why we find it pleasurable. In this chapter I will offer a fourth perspective: that our attraction to music results from a developmental requirement that we experience distinct classes of auditory stimulation for normal brain growth and maturation throughout life but particularly during the first two decades. We will find that there are innate constraints on musical sensitivity that transcend cultural differences and provide a core set of features common to all styles and genres. These features have a great deal in common with the singsong of motherese and will offer clues as to why we find pleasure in music as well as many other types of acoustic experiences.

Music is said to be the universal language, but exactly what properties, if any, can be found that transcend culture, geography, and time? Most people prefer the musical genre they grew up with, and even the most casual observer must concede that there is tremendous variation in style from generation to generation. Clearly, learning plays a large role in shaping the specific musical idioms we prefer. Research throughout the past decade, however, has begun to show that certain sounds and note combinations have virtually universal effect on the emotions of listeners independent of the culture in which they were born, raised, and live. Moreover, most neurologically normal listeners, no matter where they are from, can agree on what is and is not musical, even when the sequence of tones is novel or drawn from a foreign scale. This has led some theorists to focus on the similarities between music and language development when speculating on the origins of musicality.

Decades ago, the linguist Noam Chomsky set out to understand why all normal children spontaneously speak and understand complex language. He pointed out that all mature speakers of a language can generate and interpret an infinite number of sentences, despite great variation in their levels of formal education. Moreover, in any given language, most native speakers can agree on whether a sentence seems grammatical. Since most speakers have these abilities despite varying levels of formal linguistic training, Chomsky argued that we are all born with an innate knowledge of language. The instinctual set of rules we unconsciously use to make grammatical judgments as well as to produce and interpret sentences is called the universal grammar. Chomsky argued that linguistic development involves the fine-tuning of this grammar toward settings appropriate to the indigenous language.

The composer Leonard Bernstein was the first to apply Chomsky’s ideas about language to music. He suggested that all the world’s musical idioms conform to a universal musical grammar. This theory was advanced more formally through the work of psychologist Ray Jackendoff and musicologist Fred Lerdahl. They viewed music as being built from a hierarchy of mental structures, all superimposed on the same sequence of notes and derived from a common set of rules. The discrete notes are the building blocks of a piece and differ in how stable they feel to a listener. Notes that are unstable induce a feeling of tension, while those that are stable create a sensation of finality or being settled. Musical styles differ in the emphasis placed on beat interval and pitch, but most genres use notes of fixed pitch.

Pitch is related to the frequency of the sound wave’s vibration that is emitted by an instrument, but is perceived musically relative to other notes and the interval separating them rather than in any absolute sense. When a guitar string is plucked it vibrates at several frequencies at once: a dominant frequency called the fundamental and integer multiples known as harmonics, which add fullness and timbre. For example, a note with a vibration of 64 times per second will have overtones at 128 cycles per second, 192 cycles per second, 256 cycles per second, and so forth. The lowest frequency—which is often the loudest—determines the pitch we hear. In this example, the fundamental frequency is 64 cycles per second and corresponds to the second C below middle C.

When a sound wave vibrates faster, say at a fundamental frequency of 128 cycles per second, we perceive the tone as being higher. Since the fundamental frequency of this new tone at 128 cycles per second is related to the other tone at 64 cycles per second by an integer multiple (128 = 64 × 2), it will sound higher but with the same pitch (a middle C).The interval that separates our two example tones at 64 and 128 cycles per second is called an octave.All primates perceive tones separated by an octave as having the same pitch quality. The pentatonic scale, common to most musical idioms across the globe, is built from having five distinct pitches within an octave. Throw in two additional pitches per octave and you have the seven-tone diatonic scale that forms the foundation of all Western music, from Beethoven to the Beatles.

Music is governed by a relatively small set of rules—like language—that can be used to generate an infinite variety of compositions. Music also employs recursion. In the same way that a sentence can be lengthened indefinitely by adding modifiers or additional words, so can a musical piece by inserting new or repeating phrasing. And just as language emerges naturally in children without a need for formal linguistic training, so too does music. Indeed, the only requirement for the development of musicality in babies is exposure to music.

As we have seen in earlier chapters, human newborns are far from being blank slates. With regard to the sensations of touch, motion, smell, and taste, they have clear preferences for certain stimulation patterns that are optimally tuned for regulating brain growth and development. The same is true for hearing. Newborns are attracted to music from birth and are sensitive to acoustic properties that are common to all music systems across cultures. By the time an infant is two months old, it will have roughly the same ability to distinguish pitch and timing differences in musical structure as that of listeners with decades of exposure to music. From the very beginning of life, newborns are attracted to specific features of music that are also preferred by adults the world over.