By Christopher A. Thurber, Ph.D.
In the spring of 2002, Psychologist Wallace Dixon published the results
of a survey of 1,500 randomly selected, doctoral-level members of the Society
for Research in Child Development (SRCD). He had asked the society members
which studies, published since 1950, they considered "most revolutionary."
In this series, psychologist Christopher Thurber — an ACA member as
well as a member of SRCD — shares a summary of the top twenty most
revolutionary studies. Thurber has grouped these twenty studies into six
topics: (1) nature and nurture; (2) attachment and temperament; (3) language;
(4) cognitive development; (5) parenting and socialization; and (6) risk
and resilience.Each of the six articles, to be published consecutively for
the 2003 volume of Camping Magazine, will present a digest of several
studies, reflections on what made the research revolutionary, and ideas
about how the findings apply to today's campers and camp professionals.
Big Questions
Few questions in science or the humanities have engaged and frustrated
scholars more than "Why are people the way they are?" We wonder:
Were we born that way? Were we injured by someone or something? Is it cultural?
Did our parents raise us that way?
The three studies reviewed in this article were revolutionary in the way
they advanced our thinking about hereditary influences and environmental
influences on development. Or, as many of us heard the issue labeled in
school — Nature Versus Nurture.
No Winner
In the Nature Versus Nurture debate, there is, of course, no winner. Therefore,
framing the question as one factor versus the other is misguided. For any
given human trait or behavior, heredity and environment do not compete to
see which will win, or which factor will emerge as the singular reason why
someone is the way they are. Instead, heredity and environment interact.
For decades now, psychologists and geneticists alike have thought of heredity
and environment as interactive — hence, the title of this article.
Nature and nurture work together — each influencing the other at different
times — to shape the way people are. Prior to the 1950s, however,
most people did think in terms of Nature Versus Nurture. Psychologist Anne
Anastasi helped change that.
What's Revolutionary?
In her 1957 presidential address to the American Psychological Association's
Division of General Psychology, Anastasi challenged her colleagues to think
in a new way: "Psychologists began by asking which type of factor,
hereditary or environmental, is responsible for individual differences in
a given trait. Later, they tried to discover how much of the variance was
attributable to heredity and how much to the environment . . . a more fruitful
approach is to be found in the question ‘How?'"
In 1957, this was a revolutionary way of thinking. Subsequent studies,
with humans and other animals, sought to answer Anastasi's challenge. Sometimes,
the results were surprising.
How Do Heredity and Environment Interact?
Two other studies on the "Top 20" list offer intriguing answers
to the manner in which heredity and environment interact. Research suggested
that some abilities, such as facial recognition and the perception of movement,
were innate. Soon after birth, maturation and learning help these abilities
develop.
In 1961, developmental psychologist Robert Fantz published a summary of
his research on infant form perception. At the time Fantz published this
work, the scientific community agreed that very young human infants could
see light, color, and movement. Fantz and his colleagues set out to learn
whether newborns had an innate ability to perceive certain forms, such as
faces. He and his colleagues had already shown that newborn chicks had a
preference for objects shaped like seeds. (Fantz had measured the pecking
frequency of newly hatched chicks who were given objects of all different
shapes.)
With human newborns, Fantz measured how long they gazed at two-dimensional
versus three-dimensional circles, high-contrast versus low-contrast designs,
and organized drawings of faces versus scrambled patterns of similar shapes.
Interestingly, newborns gazed longer at three-dimensional objects, high-contrast
designs, and faces.
Fantz deduced that human babies are hard-wired to recognize visual stimuli
that are important for survival and later development. But Fantz also cited
studies that showed how visual perception was impaired when animals were
deprived of certain visual stimuli for some period after birth.
Thus, his conclusion was: ". . . there appears to be a complex interplay
of innate ability, maturation, and learning in the molding of visual behavior,
operating in this manner: there is a critical age for the development of
a given visual response when the visual, mental, and motor capacities are
ready to be used and under normal circumstances would be used together.
At that time, the animal will either show the response without experience
or will learn it rapidly."
To understand Fantz's conclusion, think about this: there are some human
traits that have a well understood hereditary cause. For example, the presence
of an extra twenty-third chromosome causes Down's syndrome. Other conditions,
such as infant lead poisoning, are purely environmental. Both conditions
result in cognitive deficits, but the causes are completely different. Fantz's
research was revolutionary in its suggestion that hereditary visual abilities
exist at birth, but that babies need exposure to complex visual stimuli
in order for these abilities to mature and develop fully. Perhaps the same
would turn out to be true for other traits.
Neural Architecture
In 1965, Harvard neurophysiologists David Hubel and Torsten Wiesel took
Fantz's research a step further. They wanted to know exactly which neurons
in the visual cortex were responsible for our innate perceptual abilities.
Of course, sticking probes in infants' brains and conducting post-mortem
exams was ethically impossible. So, Hubel and Wiesel used very young kittens.
(This may also seem unethical, but the findings have guided our treatment
of numerous visually impaired humans.)
Hubel and Wiesel measured the electrical impulses of individual brain neurons
when kittens were exposed to moving patterns on a screen located about five
feet from the kittens' faces. Their revolutionary finding was that kittens
had specific neurons that were activated by specific patterns. For example,
one set of neurons was activated by a line on the screen that moved up and
down; another set of neurons was activated by a line that moved left and
right. The "hard wiring" that Fantz had hypothesized could be
physically located in an animal's brain!
The most extraordinary part of this research was that different kittens'
neural responses were the same, regardless of whether the kittens had spent
their first open-eyed days in total darkness or in light. Hubel and Wiesel
concluded that what Fantz had called "critical periods" may not
be — at least for some innate abilities — as sensitive to environmental
stimuli as had been believed. In other words, the neural architecture that
enables animals to do some of the things they do is there at birth and easily
activated without extensive prior exposure or learning.
It Matters
This research by Fantz, Hubel, and Wiesel matters to anyone who works with
children. These studies, and many subsequent studies, have helped answer
Anastasi's challenging question about how heredity and environment interact
(or do not interact) to shape different human traits. Knowing something
about how heredity and environment have interacted over the course of a
child's life to shape a certain behavior guides our approach with that child.
Take, for example, a noncompliant behavior. Imagine that you explain to
your campers during orientation that they are not allowed in the water without
the permission of an adult. On the second day of camp, you see a camper
wading into the water and you shout, "Please come out of the water!
General swim starts at 11:30. Until then, no campers are allowed in the
water." But the camper fails to comply and continues wading into the
water. What's going on? In this case, knowing something about the hereditary
and environmental causes of the camper's behavior will guide your approach.
Perhaps the child was born deaf, with a congenital defect in her auditory
cortex. She didn't hear your explanation at orientation, and she's not hearing
your shouting now. In this case, you'll have to write or use sign language.
The point is that the camper's noncompliant behavior is not intentional.
In other words, she is not behaving defiantly, just ignorantly. She doesn't
know better, and your approach would first be to teach her the rules in
a way she can understand.
Alternatively, perhaps the child hears perfectly well, but has never experienced
reasonable consequences for her misbehavior. Her parents and teachers were
permissive, and the camp she went to last year allowed the campers to wade
into the water without adult supervision (!). Given her environmental exposure,
it's logical that she hasn't heeded the rules you explained. Naturally,
your approach would be different than with the deaf child. This defiant
child needs a second explanation of the rule, a reasonable consequence for
her misbehavior, solid examples of good behavior to follow, and a continuous
set of boundaries that are consistently reinforced by the entire staff.
She will have to learn what adult authority is.
In this example of a single behavior, one begins to appreciate the importance
of understanding causes for behaviors. As fate would have it, though, most
explanations for child behavior are not as attractively simple as our noncompliant
bather. Why else might she be disobedient?
As Complex as It Gets
Despite decades of quality psychological research, complex human behaviors
— including the full range of abnormal behaviors we all see at camp
— are still a confusing tangle of hereditary and environmental factors.
High-tech brain imaging techniques, such as functional magnetic resonance
imagery (fMRI) have helped us see the human brain in action like never before.
Imagine how excited Hubel and Wiesel would have been to have this technology
in the early 1960s! But just knowing the neurochemistry involved in a behavior
doesn't necessarily answer Anastasi's question of how nature and nurture
have interacted to cause a particular trait. With each child, we need to
become a sort of "behavior detective."
For example, we know that children with true Attention Deficit Hyperactivity
Disorder (ADHD) have a biological deficit (itself the result of a complex
heredity-environment interaction). In these children, certain neural pathways
between their brain stem and frontal lobes don't have enough of the neurotransmitters
dopamine and norepinephrine. Without enough of these important chemical
messengers, these children have difficulty sustaining attention.
Of course, treating the chemical dysfunction in these children's brains
with stimulant medications is tremendously helpful. But, as anyone who works
with children with ADHD can tell you, both medical treatment and adjustments
to the environment are necessary for maximum symptom relief. This is where
the detective work comes in.
Knowing the biological facts does not explain why a particular child does
not pay attention in a particular instance. To know this, we must also know
the history of how that child has been treated by others, the tasks to which
that child has been exposed, and the rewards that child has received for
paying attention in other circumstances. Knowing all this, of course, is
impossible. At best, camp staff get a tiny snapshot of a camper's history.
At worst, parents with-hold pertinent information, and staff must rely on
intuition.
Using What You Know
The three landmark studies reviewed in this article provide a scientific
basis for a useful approach to managing camper behavior. First, we must
"use what we know." We know that every camper was born with some
hard-wired traits. We also know that in the years before they attend our
camp, their hard-wired neural networks have grown, as a consequence of maturation
and learning. We know that each camper was exposed to different environmental
stimuli. Some of those stimuli have even promoted new neural connections
and literally changed some of the hard wiring. Finally, we know that most
of the behaviors, thoughts, and emotions that our campers possess reflect
years of complex interactions between heredity and environment.
Knowing What to Use
We stretch our understanding of the nature/nurture question each time we
sit up late on the lodge porch lamenting, "I just don't understand
what drives this kid." At camp, our campers captivate and concern us,
often leaving us asking, "Where did this child learn such a behavior?"
Or, "What kind of parents does this child have?" Or even "How
can a child be born like this?"
It's at frustrating moments such as these when we must "know what
to use." Below is a list of suggestions for applying our knowledge
of the heredity and environment interaction.
- Use your camp's health form to garner as much helpful information about
each camper as you can. Ask not only medical history questions (which
are primarily heredity-type questions) but also nurturing questions about
the child's bedtime routines, previous experience away from home, exposure
to violence, social skills, and self-discipline.
- In cases where a camper's behaviors, thoughts, or emotions seem mysterious
or abnormal, consult the child's parents. Although biased, parents know
more about their child's heredity and environment than anyone.
- In cases where a camper has received professional treatment for a physical
or psychological condition, consult the child's care providers. This requires
parental permission, but it can offer useful treatment strategies to continue
at camp.
- Prevent your own temper from flaring in response to misbehavior by
reminding yourself that what you're seeing is partly a reflection of a
genetic and social history. Take heart in the opportunity you have to
expose this camper to your healthy camp environment. You are adding the
next chapter to that child's history.
- Never say, "We only have a few weeks with this camper. That's
not enough time to promote meaningful change." Set the realistic
goal of sharing your camp's way of living and caring with each child.
Know that you've planted a seed that may blossom years down the road.
- Provide a loving and safe set of consequences. (Many campers may not
have had such exposure.) Praise positive behaviors and redirect negative
behaviors through reasoning, distraction, withdrawal of privileges, and
natural consequences.
- Work hard to make your camp and your staff as nurturing as possible.
Camp can be, quite literally, an environmental force in children's lives
that changes forever their brain chemistry and neural pathways.
Big Answers
Each of us arrives in this world with a genetic endowment primed for learning.
Perceptual skills, such as vision, take only limited environmental exposure
to be activated. More complex skills, such as language, take more time to
learn, but are possible only because our brains have the necessary structures
to acquire syntax without effort. And the most complicated skills, such
as impulse control or understanding our own emotions, take years of practice,
loving guidance, and brain tissue maturation.
So, the next time you praise a camper or stop him from fighting or put
your hand on his shoulder to comfort him or remind him to take his medication
or use humor to keep his attention or smile back when he smiles at you,
remember that you've just provided the next important piece of nurturing
in his young life. Over time, your nurturing will influence his very nature.
References
Anastasi, A. (1958). Heredity, environment, and the question “How?”
Psychological Review, 65, 197-208. (ranked 14/20)
Franz, R. L. (1961). The origin of form perception. Scientific American,
204, 66-72. (ranked 19/20)
Hubel, D. H., & Wiesel, T. N. (1965). Receptive fields of cells in striate
cortex of very young, visually inexperienced kittens. Journal of Neurophysiology,
26, 944-1002. (ranked 13/20)
Originally published in the 2003 January/February
issue of Camping Magazine.
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