Learning #2

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Classical conditioning forms associations
between stimuli (a CS and the US that it
signals). It involves respondent behavior,
actions that are automatic responses to a
stimulus. For example, salivating in
response to food and later in response to
a tone.
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In operant conditioning, organisms
associate their own behavior/actions with
consequences. Actions/behaviors
followed by reinforcers increase, those
followed by punishers decrease. Behavior
that operates on the environment to
produce rewarding or punishing stimuli is
called operant behavior.
Operant
Classical
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Law of Effect: the law of effect was
developed by Edward Thorndike (18741949). The law of effect states that
rewarded behavior is likely to recur.
Behaviors that are followed by favorable
consequences become more likely and
behaviors followed by unfavorable
consequences become less likely.
Edward Thorndike’s law of
effect is one of the few
laws of psychology.
Thorndike developed his
law through research with
cats. The cats were
placed in puzzle boxes
that required the cat to
perform various actions.
The cats were enticed
then rewarded with fish,
once they had made it
out of the box.
Thorndike discovered that
the cats performance
tended to improve with
successive trials. This
illustrates his law of effect.
Using the work of Thorndike as a starting
point, Skinner developed a behavioral
technology that reveals principles of
behavior control. Skinner was able to train
pigeons to do many behaviors that were
not pigeon like.
 Skinner designed an operant chamber for
his studies. It is commonly known as the
Skinner box. The box has a key or bar that
the animal must press . The action releases
a reward of food or water.
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Shaping behavior is essential to operant
conditioning. Shaping is important
because humans and animals rarely
perform the desired behaviors the first
time around. They need a hint as to what
is required.
 How does shaping occur? Shaping is a
process where reinforcers are used to
guide a subject’s actions toward a
desired behavior.
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Shaping works by step by step reinforcement of
appropriate behavior.
If the researcher wants the rat to press a bar:
Step 1: reward when it approaches the bar
Step 2: once this is normal behavior do not reward
unless the rat moves closer to the bar
Step 3: once this is normal behavior do not reward
unless the rat touches the bar
Step 4: do not reward unless the rat presses the bar
This process is called successive approximations.
Reward behaviors that are ever closer to the goal but
do not reward any other actions. Through this process
animals can be taught complex behaviors.
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We can use shaping to understand
nonverbal subjects. In 1964, Herrnstein and
Loveland trained pigeons to respond to
discriminative stimuli. They would reinforce
the pigeon for pecking at a picture of a
human face but not other pictures. The
face is the discriminative stimulus. After
being trained to discriminate among
objects like flowers, humans, cars, etc, the
pigeons could usually identify a new picture
and place it in the correct
category.(Bhatt,1988; Wasserman,1993)
A reinforcer is any event that strengthens
the behavior it follows.
 Reinforcers can be tangible, verbal or
can be an activity.
 Positive reinforcement: increasing
behaviors by presenting positive stimuli.
A positive reinforcer is any stimulus that,
when presented after a response,
strengthens the response.
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Negative reinforcement: increasing
behaviors by stopping or reducing
negative stimuli (such as shock). A
negative reinforcer is any stimulus that,
when removed after a response,
strengthens the response
Positive
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Add a desirable stimulus
Examples: getting a hug
Getting a paycheck
Receiving a food reward
Praise or attention
They can vary with circumstances, what is
appealing to one may not appeal to
someone else, or may not appeal to you at
that time
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Remove an aversive stimulus
Examples: buckle up to stop the beeping
Hit the snooze to stop alarm
Take drugs to stop withdrawal pangs
Take an aspirin to stop pain
Escape shock
Negative reinforcers are not punishment
Negative
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Primary reinforcers: an innately
reinforcing stimulus, such as one that
satisfies a biological need. Example:
getting food when hungry or receiving
pain relief when you have a headache.
 Conditioned reinforcers: a stimulus that
gains its reinforcing power through its
association with a primary reinforcer, also
known as a secondary reinforcer.
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For example, Skinners rats associate a light with
food. If they turn on the light, they receive
food, therefore they will work to turn on the
light. The light has become a conditioned
reinforcer.
Researchers (Briers et al.,2006) looked into the
research question that because food and
money are linked, people who are hungry
would be more money hungry. People were
less likely to donate to a charity when food
deprived, and less likely to share money with
fellow participants when food aromas where
present.
Immediate reinforcers: reinforcers that
occur immediately after the desired
behavior. In animal research immediate
reinforcers are critical. Humans however
will respond to delayed reinforcers. The
paycheck you receive after a week or
more of working is an example of delayed
reinforcement.
 Those that are willing to accept delayed
gratification have been shown to become
socially competent and high-achieving
adults.
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Continuous reinforcement: reinforcing
the desired response every time it occurs
 Partial (intermittent) reinforcement:
reinforcing a response only part of the
time, results in slower acquisition of a
response but much greater resistance to
extinction than continuous
reinforcement
 Example: slot machines
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Partial reinforcement schedules:
 Fixed-ratio schedules: reinforces a
response only after a set number of
responses: example: after you buy 10
you get one free deals
 Variable-ratio schedules: reinforces a
response after a varied number of
responses: example: slot machines
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Fixed-interval schedules: reinforces the
response only after a set amount of time
elapses
 Variable-interval schedules: reinforces
the response after varying amounts of
time have elapsed
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Cognitive processes do impact operant conditioning. For
example, rats and other animals on a fixed interval
schedule will respond more frequently as the time for a
reinforcer grows near. The rats behave with expectation.
They act as if they expect repeating the response to
produce the reward.
 Latent learning: rats were placed in a maze and allowed
to explore it for 10 days. They received a food reward for
completing the maze. The rats demonstrated their prior
knowledge by completing it as quickly as rats that had
been rewarded for running the maze all along. The rats
seem to have developed a cognitive map. The rats prior
knowledge is not activated until a researcher places a
reward in the goal box at the end of the maze. They
developed latent learning, which is learning that is not
evident until there is an incentive to demonstrate the
learning.
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Insight: we suddenly see the answer
where before it seemed as if there was
no answer. The problem is a baby robin
falls into a narrow opening 30 inches
deep in a cement block wall. How can
the robin be rescued?
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A 10 year old boy solved the problem,
when several construction workers could
not. Add sand a little at a time giving the
bird time to adjust to the sand. As the
san rises so will the bird.
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Intrinsic motivation: a desire to perform a behavior
solely for its own sake
Extrinsic motivation: a desire to perform a behavior to
receive the promised reward or avoid the threatened
punishment.
Excessive rewards can undermine the intrinsic
motivation. People may believe that if they must be
rewarded that they behavior as no value on its own.
Motivation studies: Deci/Ryan; if you want a behavior
to be long term focus on the intrinsic/Patall; choice
encourages intrinsic motivation/Boggiano; rewards
effective if used not to control but to signal a job well
done/Eisenberger&Rhoades, Henderlong& Lepper;
rewards can boost creativity, raise performance,
increase confidence and increase enjoyment
An animal’s biological predispositions will
restrict its ability to be trained through
operant conditioning.
 Hamsters could be operantly
conditioned (with a food reinforcer)to
rear up or to dig but not to wash its face.
Standing up and digging are part of the
hamsters’ normal food seeking behaviors
but face washing is not.(Shettleworth,
1973)
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Instinctive drift: occurs when trained animals
revert to their biologically predisposed
patterns.
The Brelands (students of Skinner) began a
business training animals for entertainment
purposes. They worked with a variety of
animals and began with the assumption that
you could train almost any response with
operant training. They soon discovered that
biological predispositions interfered. Pigs
trained to pick up coins and carry them soon
began to drop them and push them with their
snouts. This is an example of instinctual drift.
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Education: immediate feedback and pacing to fit each individual
student was Skinner’s dream. Although, we are not yet taught by
computers, the computer has changed education with online testing,
interactive learning software and web-based learning.
Sports: using reinforcement techniques to improve athletic performance.
For example, teaching golf students to putt by beginning with very short
putts and rewarding success, then over time lengthening the
putts.(Simek,O’Brien,1981,88)
Work: reinforcing appropriate work behaviors with immediate
reinforcement. The reinforcement can be either financial or praise, both
can be effective. Reward specific behaviors, not just a vague concept
like merit.(Baron,1988)(Peters, Waterman,1982)
Home: reinforce appropriate behaviors in children by reinforcing correct
behaviors as opposed to punishing incorrect
behaviors.(Wierson,Forehand,1994)
Self-improvement: reinforce the desired behaviors and extinguish the
undesired ones. Psychologists suggest the following four steps:1)State
your goal in measurable terms 2) Monitor how often you engage in the
desired behavior 3) Reinforce the desired behavior 4) Reduce the
rewards gradually
Observational learning: learning by
observing others, also called social learning
 We learn all types of behaviors by imitating
others. Those we imitate are the models
and our imitation is called modeling.
 Mirror neurons play a role in observational
learning. These neurons fire when an action
is performed but also when the same
action is observed. Our mirror neurons
underlie our strong social nature.
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Young humans’ behaviors are shaped
by imitation. Babies will imitate certain
actions at a very young age. By 8 to 16
months, infants will imitate novel gestures
(Jones,2007). By 12 months, they will look
where an adult is looking (Brooks &
Meltzoff,2005) By 14 months, they will
imitate acts seen on TV (Meltzoff &
Moore, 1989,1997)
In 1961, Bandura set up an experiment
researching imitative
behavior/observational learning.
 A preschool age child is in a room
working on a drawing, in the same room
and adult is playing with toys. The adult
suddenly gets up and for about 10
minutes beats, throws and even kicks a
large Bobo doll, while yelling.
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The child is then taken to another room with
really cool toys, but the experimenter tells
the child that they cannot play with those
toys. The child is then taken to another
room, where there are a few toys, including
a Bobo doll. The child is left alone. Those
that have been with the adult model are
much more likely to respond to the Bobo
doll in a similar fashion than are children
who were not exposed to the adult model.
The children not only acted similar to the
adults, they mimicked exactly the adults
actions and words.
 Why would the children imitate the
behavior? Why do we imitate certain
models? Bandura believed that it was
connected to reinforcements and
punishments. We anticipate a behavior’s
consequences by watching the model. We
imitate people we perceive as like us or as
successful and admirable.
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Prosocial effects: positive models can
have prosocial effects. For example,
want to raise a reader, read to them,
surround them with books, read with
them, read in front of them.
 Positive role models can encourage
positive behaviors. Models are most
effective when consistent, words and
actions match.
 Parents are powerful models.
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Antisocial effects: observational learning of negative,
antisocial behaviors.
May explain why the children of abusive parents are
more aggressive.
Media may have an impact. For example, homicide
rates rose during the same time period that TV was
widely spreading across the country.
The violence viewing effect (Donnerstein,
1998)indicates that the amount of violence watched
, the attractiveness of the perpetrator, and the lack
of a negative outcome are linked to aggressive
violent behaviors.
The violence viewing effect stems from 1) imitation
and 2) desensitization over time.
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