~ • ~ • ~ • ~
1.3.1
NOT
OUT
OF THIN
AIR:
MUSIC
COMES
FROM EVOLVED
BRAIN
“MODULES”
Some people believe music comes wafting magically
out of thin air in the form of mysterious, disembodied “inspiration.” It then
presumably lodges in the skull of the composer or songwriter, who feverishly
jots it down or records it on a tiny digital device, and later claims, “It just
came to me in a flash. I wrote the whole song in 23 seconds.”
That’s
where music seems to come from. But the musical inspiration you enjoy actually
comes to you courtesy of the parallel processing that goes on in certain
integrated “modules” within the fascinating neuro-computational organ located
inside your head.
Your brain processes music and also creates music.
So,
what’s a module?
It’s
a network of brain cells, a brain structure, that has evolved to carry out some
specialized function. The Canadian cognitive psychologist Steven Pinker, in How the Mind Works,
describes the mind as “what the brain does,” or, more specifically,
... not a single organ but a system of organs, which we can think of as
psychological faculties or mental modules.
Evidence from cognitive science, neuroscience, evolutionary
biology, evolutionary psychology, and other disciplines points to the
existence of numerous such brain structures. Possibly hundreds of
them. A mental toolbox that enables you to survive and replicate
your genes in your offspring.
Consider
your body’s architecture. You have many physical body parts, external and
internal—hands, feet, lungs, heart, etc. You can easily identify numerous
sub-parts as well: each of your hands has fingers, fingernails, knuckles, a
thumb, palm, muscles, ligaments. Every normal human is born with these physical
internal and external body parts.
The
same applies to your brain’s architecture. Even though you can’t see your
brain’s modules, they’re as real, and as different from each other, as your
hands and your liver. And, like the rest of your body parts, you have these
brain structures at birth.
All
other humans on the planet are born with the same brain modules as you, just as
they’re born with the same internal and external body parts that make all of us
identifiably human. And that means, as discussed later in this chapter, humans
show remarkable similarities in behaviour in every culture globally.
Brain
modules or faculties vary slightly from individual to individual, just as other
body parts do. The feet you were born with, for example, have the same basic
structure and anatomy as everybody else’s feet. While easily identifiable as
“feet,” your feet vary slightly from everyone else’s; they’re
identifiably yours.
Same
with the mental faculties or modules you were born with. While each one performs
the same specialized function in every human brain, your modules vary slightly
from everyone else’s. But, like your feet, your mental modules still perform in
a recognizably human way. That’s why human culture shows so much similarity
everywhere in the world. And that includes musical similarity, discussed in more
detail later in this chapter.
Multiple Intelligences
What exactly is intelligence? Usually, it’s defined
as the ability to understand, reason, and solve problems. So IQ tests focus on
logical and verbal abilities.
However, according to the theory of multiple
intelligences (controversial, but nonetheless intriguing because it jibes with
evidence that the mind has evolved as a complex modular system), humans have
other kinds of intelligence—interpersonal intelligence, kinesthetic
intelligence, visual intelligence, and so on. One of these is musical intelligence.
Most people excel at only one or two kinds of
intelligence. For instance, if you’re gifted as a musician, and also have an
outstanding ability to empathize, then you might have exceptional potential for
writing songs—and yet score only average on a standard IQ test.
|
1.3.2
YOU
WERE
BORN
WITH A PERSONALITY
The genetic code to build a head full of specialized modules evolved
in response to selective pressure over millions of years. Being born
with music-acquisition, language-acquisition and other skills and
abilities already wired in your brain means you were born with a
basic personality. You inherited it from your parents. But the
personality you had at birth differed substantially from the
personalities of your parents.
Your
modular brain structures are not completely developed, connected, and
constructed at birth. That’s why it takes some time before you can talk and
sing.
The
same applies to other aspects of your development. It takes several years before
your permanent teeth come in. If you’re female, you don’t begin to develop
breasts until puberty. If you’re male, you don’t grow facial hair until then.
Nevertheless, at birth, you have the brain wiring in place for all this to
happen.
From
childhood on, the surrounding culture shapes the personality you were born with,
but does not replace it. The personality you have today owes its character
partly to your genetic inheritance (perhaps half), and partly to your personal
environment (perhaps half)—especially your peer group.
(NOTE: This does not mean that your genetic inheritance causes
50% of your personality and your peer group causes the other 50%.
Instead, it refers to observed variance in measures of personality
and behaviour due to diversity among individuals in all kinds of
areas related to upbringing, such as education, religion, leisure
activities, and so on.)
Genetic
inheritance influences everyone’s behaviour today, as it always has. That is, no
matter how “enculturated” we humans think we’ve become, we have not by any means
“outgrown our genes”!
1.3.3
MODULES
AIN’T
COMPUTERS
At birth, your brain came equipped with numerous
pre-wired adaptations—precisely the opposite of a “blank slate” (more on this a
bit later). Your brain does not function like a “general-purpose computer” with
a single processor. As an example of the inborn modular nature of the brain,
consider the brain circuitry for modelling objects visually. It exists in the
brains of all people at birth—even
people born blind. That is, some people blind from birth can
accurately draw objects in proper 3-D visual perspective, a skill they
could not possibly learn from the surrounding culture. For example,
a Turkish artist named Esref Armagan, who has been blind since
birth, can paint realistic compositions of things he has never seen,
with accurate three-point perspective and scale size.
Your
brain’s modular architecture does not resemble conventional computer design.
Pinker again:
The word ‘module’
brings to mind detachable snap-in components, and that is misleading. Mental
modules are not likely to be visible to the naked eye as circumscribed
territories on the surface of the brain, like the flank steak and rump roast
on the supermarket cow display. A mental module probably looks more like
roadkill, sprawling messily over the bulges and crevasses of the brain. Or it
may be broken into regions that are interconnected by fibers that make the
regions act as a unit . . . the metaphor of the mental module is a bit clumsy;
a better one is Noam Chomsky’s ‘mental organ.’
If you
own an ordinary desktop or notebook computer, it’s a serial computer that
mimics a parallel computer. Unlike your brain, a computer processor executes
only one instruction at a time. But it does its work so fast that it usually
fools you into thinking it’s doing several things at once.
That’s
not how your brain works. Brain structures tend to evolve as specializations for
various tasks, such as detecting danger, recognizing faces, protecting kin,
mating, predicting the behaviour of others, and playing the harmonica for your
horse.
Taken
together, your brain’s constituent modules do not function like a conventional
computer. Nor like computer software. Nor like a mechanical clock. Rather, they
connect up in vastly complex networks of neurons that communicate with each
other and vie for your attention. Your brain is a massively parallel neural organ of
computation, not a serial one. That is, unlike a small conventional
human-made computer, your small conventional human brain
processes information and interpretations using many different
modules simultaneously. That’s why you can drive your car, drink coffee,
talk on your cell phone, and run over a pedestrian, all at the
same time. Try programming a computer to do that!
1.3.4
EVIDENCE
FOR BRAIN
MODULARITY
Where does the evidence of brain modularity come from?
Studies of patients who have experienced brain lesions
(structural changes in the brain) due to injury or disease reveal brain
modularity. Many patients exhibit the same behavioural changes or
deficits after suffering a brain lesion that occurs in the same physical
area of the brain, often due to a stroke. Observations of the effects
of injuries and diseases occurring in different parts of the brain have
disclosed a number of modules.
Another
source is measurement and observation of brain activity using positron emission
tomography (PET) and functional magnetic resonance imaging (fMRI). These
techniques reveal which specific parts of the brain are active during the
performance of a mental or physical task. If, in many individuals, the same
specific areas “light up” during the performance of the same task, it indicates
a module or modules at work.
Some
other information sources that scientists in a variety of specialties use to
investigate the functioning of the brain’s mental organs are:
• Observed effects of abnormalities in specific genes that
implicate certain modules, such as the FOXP2 gene and
language (discussed a bit later in this section)
