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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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