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August 12, 2002
A: FROM MENTOR DENISE HARBERT. To read bio. click
here.
Hi Kyndra. It sounds like you're interested in Psychology.
My first college Psych course had an excellent textbook that
you might be interested in. It was called Psychology and was
written by John P. Dworetzky. I found new and used copies
on www.amazon.com, so it looks like the book is still in print.
It's got some pretty advanced topics, but explains them in
fairly clear English and gives a lot of great examples.
Konrad Lorenz coined the phrase "imprinting" when
describing the way newborn goslings identify the first object
that moves past them after hatching, then follow that object
everywhere it goes. This is not really a type of "learning",
but a genetically inherited behavior required for survival.
Generally speaking, most goslings imprint on their mothers,
who then lead by example while the goslings follow and mimic
her behaviors. This is how the goslings learn to find food,
fly south for winter, etc. The movie "Fly Away Home"
is about how a group of goslings imprinted on a 13 year old
girl, Amy. She cares for the birds, but eventually realizes
that they must learn to fly south for the winter. Problem:
geese learn to fly by mimicking the object they imprint on
and Amy can't fly. So Amy's dad builds two makeshift planes
and the two of them bond as father and daughter while teaching
the geese to fly south…
Ivan Pavlov was the first person to document the process
of classical conditioning. Pavlov was a physiologist who had
won a Nobel Prize for his research on digestion, and had primarily
studied the digestive process in dogs. Pavlov noticed that,
after a while, his dogs would begin salivating as soon as
they heard him use the tuning fork that he served them with.
Although other researchers had discovered this as well, he
was the first one who wanted to know what was happening. The
physiological response of salivation is usually caused by
the smell or sight of food. How could a fork cause salivation?
Pavlov wondered if the dogs could be conditioned to salivate
when presented with a sensation that had nothing to do with
food. He chose sound, which he reasoned should not trigger
a physiological response to food. He found a bell, rang it,
and confirmed that the dogs did NOT salivate at the sound
of the bell. He then started to ring the bell right before
he presented the dogs with food. Once the dogs saw or smelled
the food, they would start to salivate. When the bell was
continually paired with the food, the dogs eventually began
to salivate as soon as they heard the bell, even if food was
not presented. Thus, Pavlov showed that the dogs learned to
associate the bell with the food. This is classical conditioning.
A stimulus that normally causes a reflex behavior is paired
with a stimulus that normally does not cause the reflex behavior.
Eventually, both stimuli will cause the reflex behavior.
E. L. Thorndike coined the phrase "instrumental learning"
in his research. B. F. Skinner simplified the instrumental
learning theory and added some more logical steps to it, using
the phrase "operant conditioning". Often, the two
theories are considered to be equivalent, but Skinner's work
is more widely recognized. Skinner proposed that a behavior
that is not known to an organism (person or animal) can be
learned by positive and negative reinforcement. Imagine trying
to teach a rat to press a lever. Rats don't do this in their
natural habitats. If a rat is put in a cage with a lever,
she will probably step on it or hit it by accident sooner
or later. Now suppose that lever dispenses food. After a few
accidental hits, the rat will learn that hitting the lever
will release food. She will then push the lever every time
she wants food. Now put two levers in the cage. One is round
and one is square. The round one gives a low electric shock
and the square one gives food. The rat presses the round one,
gets a shock, presses the square one, gets food, presses the
round one, gets a shock, etc. Eventually, the rat will learn
to avoid the round one and only push the square one. Learned
behaviors can become more and more complex by short increments
until the rat is doing things that make her seem highly intelligent,
even though she is just a rat learning simple tasks with increasingly
sophisticated reinforcements.
"Insight learning" is not an established phrase
like the other three you asked about. I'm guessing you might
be referring to the theories developed by Wolfgang Kohler
while he studied a group of chimpanzees in captivity on an
island near North Africa. Kohler presented the chimpanzees
with puzzles that had to be solved in order for them to get
bananas (their favorite food). He would put bananas just out
of reach and would give the chimpanzees "tools"
that they could use in a specific way to get the bananas.
Kohler observed that the chimpanzees would try to reach the
bananas with their hands first. If that didn't work, they
would look around to see if there was another way. When they
saw Kohler's "tools", they would touch them and
examine them, put them down, and walk away. They would appear
to have expressions similar to the expressions of humans who
are thinking hard about a problem. Then, suddenly, they would
run to pick up the tools, put them together in a new way,
and use them to get the bananas. Kohler believed that the
chimpanzees used their "insight" to solve problems
in creative ways. He believed they were mentally manipulating
the objects around them to think of different ways that they
could be put together. Eventually, they would figure out a
solution and would put their mental idea into action.
In short, imprinting is a genetically programmed response
and learning through imprinting is all about mimicking behavior.
Classical conditioning involves learning to associate a new
object with an automatic reflex behavior that the organism
already does naturally. Operant conditioning describes how
an organism accidentally stumbles across a new behavior that
is not a natural reflex, but is learned and repeated through
positive and negative reinforcement. Insight describes how
an organism can consciously use mental thought processes in
order to invent a new behavior to solve a problem.
This might also give you some insight into your question
about how the "nature vs nurture controversy" applies
to behavior. Nature refers to genetically programmed processes
(heredity) such as imprinting, automatic reflexes, color blindness,
certain diseases, etc. Nurture is how the environment (organisms
and objects around you) influences you. Things like intelligence
might be a combination of nature and nurture. Some people
are born with mental limitations or excessive mental abilities
due to brain chemistry, which is probably inherited. On the
other hand, a child born with excessive mental abilities is
unlikely to learn physics if she lives her whole life without
ever encountering a person who knows something about physics.
She has to be nurtured, or influenced by someone or something,
to learn physics. You might want to check out my biography
for a story of how I had an instinctive ability for something
(nature) that I never would have discovered if my dad hadn't
pushed me in that direction (nurture).
Good luck! Let us know if this helps you understand…
August 9, 2002
A: FROM MENTOR CAROL TOMAN. To read bio. click
here.
Imprinting is a very low-level neurological function that
appears at a
specific time during maturation that has survival value for
young
birds -- they are destined to imprint on the thing they see
moving
right after they hatch. This differs from the other processes
you
list in that it is very specific in applicability (birds),
time (right
after hatching), and method (it is visual and requires motion).
The
two conditioning methods that you list are more general in
that they
can be applied to pretty much any animal with a sufficiently
complex
brain and they can be applied to "teach" a wide
variety of behaviors.
Conditioning is not really "learning" though, it
is "training". The
key difference between learning and training is that training
does not
transfer to different circumstances. For example, training
a rat to
push a red lever to get cheese and avoid the blue lever which
gives a
shock can be done with conditioning. Put him in a cage with
a red
rope and blue rope and the rat will most likely not expect
the red
rope to provide food, but a human being probably would draw
that
conclusion. That is because a human is capable of learning
from the
training, and transfering that knowledge to new circumstances.
I'm
not really sure what the term "insight learning"
means, but it might
refer to this ability of humans (and probably a few other
animals like
the other great apes, parrots, dolphins, etc.) to generalize
their
prior experience into new situations. I'd recommend reading
about the
differences between these terms in a textbook on psychology.
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