It
wasn’t until the Darwinian Revolution of the past century that
science finally began to make some sense out of where humans come
from.
Cultural evolution has now become much faster and more
profound than what business-as-usual Darwinian processes are
currently doing in biological evolution. Culture interacts with
developmental processes, as in my example of how structured stuff
could have become possible at earlier and earlier ages. A number of
present-day human abilities have some potential for future
elaboration even without natural selection helping. Reading and
writing will serve as a good example.
The percentage
of Europeans who were literate did not begin to increase
substantially until the Protestant Reformation, with its emphasis on
everyone (even women) reading the Bible themselves rather than just
relying on a priest to interpret it for them. So until
a few centuries ago, only a small percentage of the population had
much opportunity to be improved by natural selection for reading
abilities.
Still, at least 85 percent of us can be taught to read
without much difficulty, even though we don’t pick it up
spontaneously in the manner of spoken language. It suggests that we
surely had the latent capacity to read before 5,000 years ago – but
that there need not be a “reading instinct” with its own brain area.
But there is a specialized brain area for
reading. How can that be?
In an adult human who can read,
you can sometimes find an area in the brain that is essential for
reading. It can do other things as well, but you can have strokes
in small areas where the only obvious symptom is that the person
loses the ability to read, without losing the ability to talk or
write. Let me give you an example of what happened to my father,
adapted from my account in Conversations with Neil’s Brain.
One day he had a bad headache, quite unlike any other he ever had
before. The next morning, he felt somewhat better and fixed himself
breakfast, then went out to pick up the newspaper off the sidewalk.
Upon sitting down to breakfast and unfolding the newspaper, he
discovered to his astonishment that he could not read it. The words
weren’t blurred. He could name the letters, but couldn’t read the
words.
Some days
later, the neurologist asked him to write out a paragraph in
longhand. My father accurately took the dictation. Asked to read
aloud from his own handwriting, he couldn’t. The neurologist had
seen this before, but I was astonished that there could be such a
“disconnect” between the two abilities. My father could name the
letters correctly. He could often correctly guess at the shortest
two- and three-letter words. But he often made errors when he would
try to piece together longer words. His spoken language was normal
and he understood everything that was said to him. He didn’t have
any abnormal blind spots that might interfere with reading and he
could drive a car without problems. He just couldn’t read anymore.
A year later, he had recovered his abilities to read the newspaper,
but he tired easily and wouldn’t read for more than 20 minutes at a
time.
So
my father, like the other patients suffering from alexia without
agraphia, appeared to have a specialized cortical area that was
essential for reading. But where could such a thing come from in
evolution, if reading is such a recent invention and the literacy
rate was too low to expose reading to natural selection for its
usefulness? One hint is that the strokes that cause such
reading-only problems are in various places in various patients, not
in some standard place common to all humans in the manner of, say,
primary visual cortex in the back of the brain.
Experience can rewire the brain
and there is some evidence that reading abilities are wired up on
the fly during childhood – as we say, they are “softwired” during
development rather than hardwired in the manner of instincts.
Self-organization from experience can create specialized areas of
expertise in human cerebral cortex, when done early enough in life –
and it changes the foundation on which later things can build. It’s
not just that the earlier you do it, the better as an adult, but
that the order in which you learn things might matter.
The science of this is not well worked out yet, but let me give you
an illustrative example from the research of my neurosurgical
colleague George Ojemann. In studying the physiological
organization of the left middle temporal gyrus (it’s just above the
left ear), he showed a strong association between the location of
specialized reading and naming sites and, of all things, that
patient’s verbal IQ. He found that patients whose sites for reading
were in the superior temporal gyrus, with naming in the middle
temporal gyrus, had high verbal IQs. And he found the reverse in
the patients with low verbal IQs. So some “residential layouts” of
these functions in the cortex are more favorable than others. Why?
Might early acquisition of reading skills lead to higher verbal IQ,
simply because phonetic languages rely on writing to represent
sounds, and the closer the reading areas are to auditory cortex, the
better?
Tune in next year – parents are always experimenting on their
children and researchers increasingly have the tools to image the
brain’s functional specializations and correlate them with test
scores and learning history – but for present purposes, I just want
this to serve as an example of how cultural feedback can cause
self-organization, softwiring the developing brain to determine
adult human capacities. It’s a softwiring example, on the
developmental time scale, of the hardwiring for acquisitiveness of
structured stuff that I sketched out earlier on the evolutionary
tweaking time scale: how overheard examples of structured stuff
could allow softwiring for structured stuff at an age where it
“takes better.”
Culture works so well in the case of reading because we have
childhood education for reading at a time when the brain is very
plastic. Does softwiring add atop more instinctive stuff – say,
sharing tendencies – to make a new type of person? Do professional
musicians develop cortical specializations for harmony that the rest
of us adults don’t have? What about logical abilities, or being
able to feel empathy well enough to routinely practice ethical
behaviors?
We know that
education matters, in the sense that ignorance is often expensive,
but does properly staged education hold the potential for
reorganizing the brain in profound ways? Even without genetic
changes, the future baby might still be like modern babies when
fresh out of the womb but become profoundly different in mental
organization before reaching adulthood.
Education
isn’t required for some
things. Children will learn to walk and talk without assistance,
though swimming, reading, and writing usually require teaching.
Recognizing someone from their face or the way they walk is a very
difficult task, judging from many decades of attempts in artificial
intelligence, but kids do them without being taught how.
It looks as if our minds come with good intuitions about
some things, but not others. There is an intuitive physics about
how objects fall and bounce but it’s not very good. If you are out
running and your keys drop out of your hand as you jump over a
puddle, and if you manage to take two more steps before you hear
them hit the ground, where did they land – back in the puddle or
after the puddle? Intuition will tell you to look back in the
puddle, where you were at the time they dropped. (This is called
Aristotelian physics – Aristotle failed to do the experiment that
would have shown him that his impetus-based reasoning was wrong.
You have to study Newtonian physics to realize that the keys
continue traveling forward at the same velocity as you were running
and so will land near your current position.)
We have an intuitive biology as well, in that we ascribe
to something a hidden essence that drives its growth and makes it
what it is. We often distinguish how from why using
an intuitive notion of evolution that ascribes purpose to living
things, as if they were designed for some goal or role. (And so we
assume a designer, unless we have absorbed the lessons of the
Darwinian process, those six essentials that can create very
improbable beings after enough generations.)
We have an intuitive psychology that helps us understand
other people, at least if we are old enough to pass that “theory of
mind” test. We treat living beings as if they were animated by
desires and beliefs. For people and pets, this works pretty well,
though some people talk to plants too. And many of us, not just the
cartoonists, intuitively ascribe higher intellectual functions to
animals without language.
There is even an intuitive economics based on
reciprocity that leads us to mentally keep track of who owes what to
whom – and to punish cheaters and freeloaders, even at cost to
ourselves. We have an intuitive notion of probability, though it is
easily fooled. We have an elementary sense of number, though real
arithmetic has to be taught.
This core of intuitions, except for the higher
intellectual functions, was likely around even before Homo
sapiens evolved. Add some protostructure such as framing and
the closed-class words and you have a considerable advance over
ape-level minds. Add some unstructured protolanguage and it becomes
even more interesting, with gossip from well-known sources providing
much experience at one remove. Hearsay was likely accepted without
much questioning or reasoning about it (it often still is). Then
structured thought itself finally emerges and we get additional ways
of organizing knowledge and discounting the fallacious flotsam.
Adding
structured stuff atop the core intuitions
took our ancestors into a realm of
creativity where we got used to doing novel things. We got used to
deciding quickly without much contemplation – and so we used those
core intuitions quite a lot, even though evolution probably didn’t
get much of a chance to debug the combination of intuition and
structured stuff.
While some of our core intuitions carry over to help us
with modern economics, there are many areas (math, science,
technology) in which we are simply unprepared for the modern world.
“It’s
not just that we have to go to school or read books to learn these
subjects,” Steven Pinker writes. “It’s that we have no mental tools
to grasp them intuitively. We depend on analogies that press an old
mental faculty into service, or on jerry-built mental contraptions
that wire together bits and pieces of other faculties. Understanding
in these domains is likely to be uneven, shallow, and contaminated
by primitive intuitions.”
Key concepts of, say, quantum
mechanics or neuroscience actually require unlearning a lot of your
intuitions. Neither Aristotelian nor Newtonian physics will help
you grasp the wave vs. particle demonstrations. And always
ascribing an actor to every action (as in those mandatory roles for
verbs in the argument structure version of syntax) will get you into
trouble searching for the seat of the soul or the center of
consciousness – when what you need are concepts of distributed,
self-organizing systems and how they handle novel inputs on the
fly. (And create new levels of organization with just the right
amounts of abstraction and anchoring – more in a minute.)
Perhaps premodern people simply weren’t conscious
in our modern sense, lacking most of that speculative “train of
consciousness” that William James talked about.
I
am conscious (aware might be the better word) of the chair
supporting me as I read. I notice the sunlight from the window
behind me. It is quickly fading and a blast of wind is rattling the
trees near the house; another shower is likely to start pounding on
the window. I am contemplating the cat, and she is contemplating
the fire in the fireplace. She has one ear cocked back, a sure sign
of an approach-avoidance conflict. I try thinking about a
feline-based metaphor for a lecture but then become self-conscious,
considering what the audience would think of me if I said something
that silly. The music in the other room just switched from Brahms
to some aborigine music. I am reminded of the Australian trip and
start speculating about the prospects for a trip to the Galapagos.
Which reminds me that I’d have to get some dental work done before
going.
The here and now, the past and future, worries and delights, self
and others – all are conscious aspects of mind. Sometimes an
agenda intrudes, as I remember to check my watch, so that I leave in
time for a pending appointment. There are nagging responsibilities
that I push onto the back burner for now. I contemplate getting up
from my comfortable chair to exercise but soon the moment passes.
My mind drifts until consciousness wanes and lapses. The telephone
awakens me and I quickly check my watch before I get up, heart
pounding. A close call.
Consciousness is, however, more than just the minimum requirements
of awake and aware. Many would emphasize that sensation becomes
conscious only when it undergoes some further processing in the
brain, as when it encounters past associations or becomes part of a
plan for action.
Some of such consciousness is likely shared with the great apes, but
probably not the speculative aspects. Nor are they likely to
experience the pangs of conscience. That takes foresight, what
augments the minor amounts of moral sense that the other apes have.
A central aspect of consciousness is the ability to
look ahead, the capability we call “foresight.” It is the ability to
plan, and in social terms to outline a scenario of what is likely
going to happen, or what might happen, in social interactions that
have not yet taken place.... It is a system whereby we improve our
chances of doing those things that will represent our own best
interests.... I suggest that “free will” is our apparent ability to
choose and act upon whichever of those [scenarios] seem most useful
or appropriate, and our insistence upon the idea that such choices
are our own.
– Richard D. Alexander, 1979
One of the reasons
that paleoanthropologists like to talk about consciousness at this
point is that modern humans seem so much more capable of high-end
cognitive functions. An umbrella-coverage term, something like the
living-nonliving distinction, is attractive to many people.
Personally, though I concede that we are conscious in ways that
great apes are not, I often avoid the C word and other such big,
loaded words when I am trying to describe things that I think of in
more textured, fine-grain terms.
There’s a famous quip by Francis Crick, about the border between the
living and the nonliving forms of matter, something that used to
cause a lot of debate in the first half of the last century. Well,
said Crick, note that this all-important boundary gradually
disappeared into just so much molecular biology. And, he suggested,
the same thing was going to happen to consciousness as a concept–
that it would disappear into just so much neurobiology. (I would
add: We’ll still talk about it, just as “alive” has remained a
useful concept, but consciousness won’t be a “thing” anymore.)
Medicine
now calms the voices and delusions,
dampens the obsessions and compulsions, and lifts the depressions.
Besides patching us up, so we aren’t hobbled, might they eventually
“improve” us so that we perform in extraordinary ways?
I’m not a big fan of optimal performance. It usually
sacrifices versatility and creativity, and so optimization often
leaves you stranded, high and dry, when the time comes to move on to
a job promotion or the next phase of life. But I can imagine much
more useful cocktails of the everyday stimulants that will help
students study better, help artists be more creative, help with
multitasking. Espresso stands will specialize in them, customizing
the mix for your desired mental set.
Most of these innovations, of course, will prove to be
illusory, mere placebos. Some will prove dangerous even in mild
daily doses, in the manner of nicotine and LSD. Others will be
efficacious but will be overused. “If some is good, more must be
better” is a fallacy recognized even in ancient Greek medicine
(almost any medicine becomes a poison in sufficient quantities).
For food and water, we fortunately satiate. But satiety often
doesn’t kick in for more novel substances such as tobacco or
alcohol. We can indulge to the point of significant impairment,
with enough softwiring changes in some individuals’ brains so that
backing up becomes very difficult (it is called addiction).
So consumer experimentation (including what
adventuresome or ignorant parents try out on their children) will be
a rocky road – but eventually, emerging from the serious research
track, there will be a science of everyday mind enhancement. Still,
I’d bet on improvements in education as the major source of enhanced
functioning, what makes genius more common and brings up the bottom.