Chapter 2 How and Why People Develop and Learn 33
how an extra chromosome 21 is responsible for Down syndrome. Down syndrome
is a disorder that causes a delay in physical, intellectual, and language develop-
ment. Genetic research will likely uncover more and more associations between
traits and groupings of multiple genes.
When considering factors that influence human development, genes are just
a part of the story. There are many genetic and environmental factors that are
connected to the development of any trait. There is still much that is unknown,
however, about the specific combinations of genetic and environmental factors
that determine traits. Just because a person has the genetic makeup to have a
trait, does not mean that the trait will develop. Assigning traits and behaviors
based on biology is called ethological theory.
How Does Environment Infl uence Development?
Even though genes determine your individual traits, the environment can
manipulate some traits. Scientists and researchers are finding many ways in
which the environment affects growth and development. Social and emotional
traits are affected by the environment, but physical traits are, too. For example,
the human brain continues to grow and develop long after birth. When children
are exposed to stimulating and interactive environments, their brains physically
respond differently from the brains of children who have not had the exposure.
The brain development of critical pathways needed for strong connections
affects children’s cognitive skills. Assigning traits and behaviors based on envi-
ronment is called ecological theory.
Family
Families affect human development
in profound ways. They offer the most
immediate setting for human develop-
ment. Children have their most frequent
interactions with family or caregivers in
the home, daycare, or school.
Many research studies suggest that
the quality of the home environment
is especially important to children’s
development and that these influ-
ences are very complex, 2-10. Good
parenting and a stimulating home
environment are consistently associ-
ated with better outcomes for children.
For example, family interactions and
activities that stimulate language and
cognitive development also promote
social development. At all ages, family
members teach children how to trade
or share toys, resolve conflicts, recog-
nize and express emotions in accept-
able ways, and interact with others in
socially appropriate ways.
lakov Filimonov/Shutterstock.com
2-10
Stress in the home has an effect on the health of
teens and adults.