Download Meyers Psych 6

Psychology in Everyday
Life
David Myers
PowerPoint Slides
Aneeq Ahmad
Henderson State University
Worth Publishers, © 2011
Learning
Chapter 6
Definition: Learning
• “Learning” is defined in psychology as ‘a
relatively permanent behavior change (or
change in mental processes) as a result
of experience.
Learning
How Do We Learn?
Classical Conditioning
 Pavlov’s Experiments
 Pavlov’s Legacy
Learning
Operant Conditioning
 Skinner’s Experiments
 Skinner’s Legacy
 Contrasting Classical & Operant
Conditioning
Learning
Biology, Cognition, and Learing
 Biological Constraints on Conditioning
 Cognitive Processes and Classical
Conditioning
 Cognitive Processes and Operant
Conditioning
 Learning by Observation
How Do We Learn?
• By linking events that occur close
together, humans and other animals
exhibit associative learning.
• This process of learning associations is
called conditioning.
• There is also cognitive learning, the
acquisition of mental information by
observing events, watching others, or
through language.
Classical Conditioning
• A stimulus is an event or situation that
evokes a response.
• In classical conditioning, we learn to
associate two stimuli; the unconditioned
response to one stimulus becomes the
conditioned response to the other.
Classical Conditioning
This woman has now been conditioned to have a negative response to the
flash of light, even before or without the loud noise.
Classical Conditioning: Pavlov’s
Classic Experiment
Classical Conditioning
• The neutral stimulus (NS) elicits no response
before conditioning.
• The unconditioned stimulus (US) is a stimulus
which triggers a reflex (automatic response, UR)
without conditioning.
• The conditioned stimulus (CS) is an originally
neutral stimulus that, after association with a US,
comes to trigger a CR.
Classical Conditioning
• The unconditioned response (UR) is an
unlearned, natural response to a US
• The conditioned response (CR) is a learned
response to a previously neutral stimulus (CS). It is
the same action as the unconditioned response,
except that it is now triggered by the formerly neutral
stimulus (now CS).
Conditioning Processes
• Pavlov and his associates identified five
major conditioning processes:
– Acquisition
– Extinction
– Spontaneous recovery
– Generalization
– Discrimination
Acquisition
• Acquisition is the first stage in classical
conditioning – where a NS is linked with a US
that the NS begins triggering the CS
Why are our bodies set up to be conditioned?
Classical conditioning helps us prepare for good
and bad events.
This is why the neutral stimulus must happen
first for conditioning to occur; it is the event we
use as a warning for the bad, a clue that helps
us find the good!
Acquisition
Extinction and Spontaneous Recovery
• If, following acquisition, the CS occurs
repeatedly without the US, it can lead to
extinction, the weakening of the CR.
• After a delay (a few hours more), however, the
CS may elicit a spontaneous recovery of a
(weakened) CR
Generalization
• Generalization: after conditioning, an
organism may respond similarly to stimuli
that resemble the CS
• This can be adaptive, but also have
lingering effects
– A child scared by a red car learns to avoid
stepping in front of all vehicles.
Generalization
• Child abuse can lead to general
hypersensitivity to the faces of any angry
person, not just their abusers.
Discrimination
• Organisms also learn to discriminate, or
distinguish, between a CS and other
stimuli.
• Consider your responses to a guard dog
and a guide dog: would they both make
your heart pound with fear?”
Pavlov’s Legacy
1. Many other responses to many other
stimuli can be classically conditioned in
many other creatures
– This is one way that virtually all animals
learn to adapt to their environment
2. A process such as learning can be
studied objectively
Can Pavlov’s work help us
understand emotions?
• Little Albert
– John B. Watson and Rosalie Rayner (1920)
worked with 11-month old boy
– Initially feared loud noises but not white rats
– Presented him with white rat, and just as he
reached out to touch it, made a very loud
noise just behind his head
– After 7 repeats, burst into tears at sight of rat
– 5 days later, he had generalized this fear to a
rabbit, a dog, and a sealskin coat
Operant Conditioning
• Classical conditioning involves respondent
behavior, an automatic response to a stimulus
• It involves operant behavior, which operates on
the environment, producing consequences
• Consequences: Reinforcers following a
behavior strengthen it (make that behavior more
likely to happen again), and Punishments
following a behavior weaken that response
(make it less likely to recur.
Operant Conditioning
(a) Response:
Balancing a ball
(b) Consequence:
Receiving Food
(c) Behavior stregthened
B. F. Skinner’s Experiments
• Skinner designed an operant chamber (aka
Skinner Box) – a box with a recording device to
track how often an animal presses a bar to
obtain reinforcement – any event or other
consequence that strengthens the behavior it
follows.
Reinforcement for the Individual
• What is reinforcing to
one individual?
• Can vary by situation –
a cold drink is
reinforcing if you are
hot, but not if you are
cold
Shaping Behavior
• Shaping: gradually guiding actions closer
and closer toward a desired behavior,
using reinforcement.
• Using successive approximations, one
rewards responses that are ever-closer to
the desired behavior.
• Through continued shaping we can find
the limits of animals’ ability to discriminate
among colors, smells, sounds.
Types of Reinforcers
• Positive reinforcement: (+, adding)
anything that strengthens a response
when presented after the response (e.g., a
food reward)
• Negative reinforcement: (-, taking away)
anything that, when removed, strengthens
a response (e.g., stopping a shock). Note:
NOT a punishment
Ways to Increase Behavior
Types of Reinforcers
• A primary reinforcer is innately reinforcing
(e.g., giving food when hungry, or alleviating a
headache).
• A conditioned (secondary) reinforcer gains its
reinforcing power through links with a primary
reinforcer.
• Most organisms require immediate
reinforcement, but humans can also use
delayed reinforcement (e.g., the paycheck at
the end of the week).
Reinforcement Schedules
• Continuous reinforcement – reinforcing
desired response every time it occurs
– Learning occurs rapidly, but so does extinction
• Partial (intermittent) reinforcement –
reinforcing a response only part of the time
– Learning is slower but increased resistance to
extinction
Partial Reinforcement Schedules
for Operant Conditioning
• Fixed-ratio schedule – reinforces response
only after fixed number of responses
• Variable-ratio schedule – reinforces response
after an unpredictable number of responses
– Produces high rates of responding
• Fixed-interval schedule – reinforces response
only after a specified time has elapsed
– Produces choppy start-stop pattern
• Variable-interval schedule – reinforces
response at variable time intervals
– Produces slow, steady responding
Schedules of Reinforcement
Punishment
• A punishment is an event that decreases
the frequency of the behavior it follows
• Two Types of punishment:
– Positive (+, adding something) Punishment
– Negative (-, taking something away)
Punishment.”
Punishment
Physical Punishment for Children:
Why Not?
1. Punished behavior is suppressed, not
forgotten. This temporary state may
(negatively) reinforce parents’ punishing
behavior
2. Punishment teaches discrimination
(rule learned: don’t swear at home)
3. Punishment can teach fear
4. Physical punishment may increase
aggressiveness
Physical Punishment for Children
• A single swat or two may be effective for 2
to 6-year-olds if:
– The swat is only used for backup when milder
tactics fail
– The swat is combined with reasoning and
reinforcing
• Remember:
– Punishment tells you what not to do,
reinforcement tells you what to do
Skinner’s Legacy: Controversy
Skinner argued that behaviors were shaped by
external influences instead of inner thoughts and
feelings. Critics argued that Skinner
dehumanized people by neglecting their free will.
Applications of Operant Conditioning
• In school: use individualized shaping to
reinforce students starting with their
current level of performance.
• At work: reinforce, even with verbal
acknowledgement, specific behaviors and
achievements
• At home: be careful not to reward
tantrums and not to be negatively
reinforced by giving in.
Contrasting Classical and
Operant Conditioning
Biological Constraints on
Conditioning
• Natural selection favors traits that aid
survival.
• This applies to conditioning: Each species
comes prepared to learn those things
crucial to its survival.
Biological Constraints on
Conditioning
Male associate red with sexual attractiveness–
why?
• Female primates display red when nearing
ovulation
• Human females tend to blush more
Limits on Classical Conditioning
• All conditioned stimuli are not equal
• Rats avoided a taste – but not sights or
sounds – associated with being sick
– Taste aversion: animals are biologically
predisposed to learn by eating food, not by
the appearance of food, which foods make us
sick.
Limits on Operant Conditioning
• Animals can most easily learn behaviors
that draw on their biological
predispositions
– YES: Train a pigeon to flap wings to avoid a
shock, and peck to obtain food
– NO: Train a pigeon to peck to avoid a shock,
and to flap wings to obtain food
• Biology predisposes us to learn
associations that are naturally adaptive
Cognitive Processes and Classical
Conditioning
• Behaviorism: The view that (1) psychology
should be an objective science that (2) studies
behavior without reference to mental processes
– Founded by Pavlov, Watson, and Skinner
– Most psychologists today agree with (1) but not (2)
• Underestimates two important sets of influences:
– Biological predispositions limit our learning
– The effect of our cognitive processes on learning
Cognitive Processes and Operant
Conditioning
• B. F. Skinner tried to downplay the role of
cognitive processes. However, they
cannot be ignored
– Rats exploring a maze develop a cognitive
map, a mental representation of the maze.
– Rats with experience in the maze exhibit
latent learning of the maze’s layout
Cognitive Processes and Operant
Conditioning
• Excess rewards can destroy intrinsic
motivation, the desire to perform a
behavior for its own sake.
• This is in contrast to extrinsic motivation,
in which behavior is performed to gain
reward or avoid punishment.
Learning By Observation
• Cognition is a factor in observational
learning, in which humans and some
other animals learn without direct
experience – by watching and imitating
Observational Learning
• Bandura’s (1961) Bobo doll experiments showed
the importance of modeling – the process of
observing and imitating a specific behavior
Mirrors in the Brain
• Mirror neurons fire when we perform
certain actions and when we observe
others performing those actions
– A neural basis for observational learning and
imitation
• Peope with autism display less imitative
behavior, and reduced mirror neuron
activity
Mirrors in the Brain
• If we see a loved one in pain, our face
mirrors their expression, and so does our
brain
Applications of Observational
Learning
• Models of prosocial behavior – helpful,
constructive behavior – can have prosocial
effects.
• Unfortunately, antisocial behavior can also be
learned by observation