Early learning can have long-lasting effects on the architecture of the brain.
According to a Stanford University School of Medicine study in owls,
early learning experiences forever change the brain's structure.
The researchers wondered how educated animals held on to their learning.
They thought that the neurons might make new connections that remained
intact in adult animals. They turned out to be right.
Neurons in the mapping part of the brain form connections with
new groups of neurons in different parts of the brain.
Adult owls that had learned behaviors as youths had both the normal
connections and the shifted connections. Those extra connections meant
that the animals could easily relearn, even as adults, behaviors.
The researcher said different parts of the brain lose the ability to make
large-scale changes in connections at different rates. It's a trade-off
between reliability and flexibility. Areas of the brain that
need to be reliable in adults, such as the ability to analyze the
world or find prey, stop making major structural changes early in life,
leaving the adult with a stable map. Other parts of the brain,
such as those involved in learning and memory, remain more open to
changes throughout life.
The results indicate that brain regions that help them sense
and interpret the world are dramatically affected by early
experiences, and educational experiences that stimulate young minds and
encourage them to explore the world in a new way may help build their
brain for future tasks.
One researcher's findings about how experiences shape the brain's architecture
help explain findings in both rats and monkeys, where early experiences
translate directly to how the adults behave and learn.
Shonkoff said the animal work has an important parallel in human development.
Making Rats Smarter
How do rats learn? Can rats be "educated?"
In classic studies, rats are placed in a complex communal environment filled
with objects that provide ample opportunities for exploration and play
The objects are changed and rearranged each day, and during the changing
time, the animals are put in yet another environment with another set of
So, like their real-world counterparts in the sewers of New York or the
fields of Kansas, these rats have a relatively rich set of experiences from
to draw information.
A contrasting group of rats is placed in a more typical laboratory
environment, living alone or with one or two others in a barren cage--which
is obviously a poor model of a rat's real world.
These two settings can help determine how experience affects the development
of the normal brain and normal cognitive structures, and one can also see
what happens when animals are deprived of critical experiences.
After living in the complex or impoverished environments for a period
from weaning to rat adolescence, the two groups of animals were subjected to
a learning experience.
The rats that had grown up in the complex environment made fewer errors at
the outset than the other rats; they also learned more quickly not to make
any errors at all.
In this sense, they were smarter than their more deprived counterparts. And
with positive rewards, they performed better on complex tasks than the
animals raised in individual cages.
Most significant, learning altered the rats' brains: the animals from the
complex environment had 20-25 percent more synapses per nerve cell in the
cortex than the animals from the standard cages (see Turner and Greenough,
1985; Beaulieu and Colonnier, 1987).
It is clear that when animals learn, they add new connections to the wiring
of their brains--a phenomenon not limited to early development (see, e.g.,
Greenough et al., 1979).