Unit 5: Learning and Memory
Chapters 8 and 9
Learning
 Nature’s most important gift to us is our adaptability
 We adapt through learning: a relatively permanent change in an
organism’s behavior due to experience
 Philosophers John Locke, David Hume and Aristotle believed that
we learn by association
Associative learning: learning that certain events occur together.
The events may be two stimuli (classical conditioning) or a
response and its consequences (operant conditioning)
Associative Learning
 Conditioning is the process of learning associations. There are two types:
 Classical conditioning: we learn to associate two stimuli and to anticipate
events
 A flash of lightening signals an impending crack of thunder, so we learn to brace
ourselves for thunder when we see lightening
 Operant conditioning: we learn to associate a response and its
consequences and to repeat acts followed by rewards and avoid acts
followed by punishment
 Pushing a vending machine button relates to the delivery of a candy bar
 We also use observational learning: learning from others’ experiences and
examples
Ivan Pavlov – Classical Conditioning
 Ivan Pavlov’s experiments explored classical conditioning and showed
how scientific research can reveal learning principles that apply across
species
 Pavlov’s study of how organisms react to stimuli in their environments
influenced John B. Watson’s idea that human behavior, though
biologically influenced, is mainly a bundle of conditioned responses
 Both Pavlov and Watson were behaviorists and believed that psychology
should study behavior without reference to mental processes
Pavlov’s Experiments - CC
 While doing experiments studying the salivary secretion in dogs, Pavlov
noticed that dogs began salivating to stimuli associated with food (food
dish, person who brings the food). Seen first as annoyances, Pavlov soon
realized they pointed to an important form of learning.
 So, Pavlov and his assistants began different experiments: they paired
various neutral stimuli, such as a tone, with food in the mouth to see if the
dog would begin salivating to the neutral stimuli alone.
 From an adjacent room they would present food at a precise moment. If
a neutral stimuli, a tone, regularly signaled the arrival of food, would the
dog associate the two stimuli? If so, would the dog begin salivating to the
neutral stimulus in the anticipation of the food?
Pavlov’s Experiments - CC
 Results: after several pairings of tone and
food, the dog began salivating to the tone
alone
 Because salivation in response to food in the
mouth was unlearned, Pavlov called it and
unconditioned response (UCR)
 Food in the mouth automatically,
unconditionally, triggers a dog’s salivary reflex.
Thus, Pavlov called the food stimulus an
unconditioned stimulus (UCS)
Pavlov’s Experiments - CC
 Salivation in response to the tone was a learned response or conditioned
response (CR)
 The previously irrelevant tone that now triggers the conditional salivation is the
conditioned stimulus (CS)
 Remember: conditioned = learned; unconditioned = unlearned
Pavlov’s Experiments - CC
Pavlov’s Experiments - CC
 Pavlov’s simple demonstration of associative learning was so
influential because the experiment identified five major
conditioning processes: acquisition, extinction, spontaneous
recovery, generalization, and discrimination
Acquisition - CC
 Acquisition: the initial stage in classical conditioning; the phase associating a
neutral stimulus with an unconditioned stimulus so that the neutral stimulus comes
to elicit a conditioned response
 Timing: would conditioning occur if the UCS appeared before the CS?
 Not likely because classical conditioning is biologically adaptive and helps
organisms prepare for good or bad events.
Extinction and Spontaneous Recovery - CC
 Extinction: the diminishing of a conditioned response; occurs in
classical conditioning when an unconditioned stimulus (UCS) does
not follow a conditioned stimulus (CS)
 Pavlov sounded the tone again and again without presenting food; the dogs salivated less and
less
 Spontaneous recovery: the reappearance, after a rest period, of an
extinguished conditioned response (CS)
 Pavlov allowed several hours to elapse before sounding the tone again; the salivation to the tone
would reappear
Generalization - CC
 Generalization: the tendency, once a response has been conditioned, for
stimuli similar to the conditioned stimulus to elicit similar responses
 Dogs conditioned to one tone also responded somewhat to the sound of a
different tone never paired with food
 Generalization can be adaptive: children taught to fear moving cars in
the street respond similarly to trucks and motorcycles
Discrimination - CC
 Discrimination: the learned ability to distinguish between a conditioned
stimulus and other stimuli that do not signal an unconditioned stimulus
 Pavlov’s dogs learned to respond to particular tones and not to other tones
 Discrimination has survival value: being approached by a pit bull may
cause your heart to race, but it may not when you are confronted by a
golden retriever
Pavlov’s Legacy
 Classical conditioning is one way that virtually all organisms learn to adapt to
their environment
 Pavlov showed us how learning processes can be studied; by isolating building
blocks on complex behaviors
 Provided a basis for John B. Watson’s work
Watson’s “Little Albert” Experiments - CC
 Watson presented 11 month old Albert with
a white rat and, as he reached to touch it,
struck a hammer against a steel bar just
behind Albert’s head
 After 7 repetitions of seeing the rat and then
hearing the frightening noise, Albert
became terrified at just the sight of the rat
 Five days later, Albert showed generalization
by reacting fearfully to a rabbit, dog, and
sealskin coat, but not to vastly different
objects like toys
Operant Vs. Classical Conditioning
 The second type of associative learning, operant conditioning: a type of learning
in which behavior is strengthened if followed by a reinforcer or diminished if
followed by a punisher
 Both classical and operant conditioning involve acquisition, extinction,
spontaneous recovery, generalization, and discrimination
 BUT classical conditioning involves respondent behavior: behavior that occurs as
an automatic response to some stimulus
 And operant conditioning involves operant behavior: behavior that operates on
the environment, producing consequences
Operant Vs. Classical Conditioning
 Organism is learning associations between events that it doesn’t
control: Classical conditioning
 Organism is learning associations between its behavior and resulting
events: Operant conditioning
B. F. Skinner’s Experiments - OC
 Centered on a simple fact of life that
psychologist Edward L. Thorndike called the
law of effect: rewarded behavior is likely to
recur
 Skinner developed a ‘behavioral technology’
that revealed principles of behavior control
Skinner Box - OC
 Working with rats, and later pigeons, Skinner
designed an operant chamber (Skinner box):
a chamber containing a bar or key that an
animal can manipulate to obtain a food or
water reinforce, with attached devices to
record the animal’s rate of bar pressing or key
pecking
 Skinner used shaping: reinforcers guide
behavior toward closer and closer
approximations of a desired goal
Shaping Behavior - OC
 Using a method of successive approximations, scientists rewards
responses that are ever-closer to the desired goal and ignore all
other responses
 By doing this long enough, researchers can eventually shape
complex behaviors
Principles of Reinforcement - OC
 Reinforcer: in operant conditioning, any event that strengthens the behavior it
follows; can be positive or negative
 Primary reinforcer: an innately satisfying stimulus, such as one that satisfies a
biological need
 Ex: getting food when you’re hungry
 Conditional reinforcer / secondary reinforcer: a stimulus that gains its reinforcing
power through its association with a primary reinforcer
 Ex: a rat in a Skinner box learns that a light reliably signals that food is coming; the rat will try to turn
the light on
Immediate and Delayed Reinforcers - OC
 Most laboratory animals only respond to immediate reinforcers, otherwise
no learning occurs
 Humans, on the other hand, do respond to reinforcers that are greatly
delayed (pay check at the end of the month, good grade at the end of
the semester)
 A huge step in the process for humans to mature and have the most satisfying
life, is to learn to delay our gratification for the benefit of long term goals
 Unfortunately, most of the time, small but immediate consequences are more
alluring than big but delayed consequences
Reinforcement Schedules - OC
 Continuous reinforcement: reinforcing the desired response every time it occurs
 Learning occurs rapidly, but so does extinction
 Partial (intermittent) reinforcement: reinforcing a response only part of the time;
results in slower acquisition but greater resistance to extinction than does
continuous reinforcement
 More applicable to real-life
Reinforcement Schedules - OC
 Skinner and colleagues compared four schedules of partial reinforcement
 Fixed-ratio schedule: reinforces a response only after a specified number of
responses
 Variable-ratio schedule: reinforces a response after an unpredictable number of
responses
 Fixed-interval schedule: reinforces a response only after a specified time has
elapsed
 Variable-interval schedule: reinforces a response at unpredictable time intervals
 Skinner found that the reinforcement principles of operant conditioning were
universal; no matter what response, reinforcer, or species, the effect of a given
schedule is the same
Reinforcement Schedules - OC
Punishment - OC
 Opposite of reinforcement is punishment: an event that decreases the behavior
that it follows
 Although punishment can be successful in suppressing a behavior, some
psychologist believe it may lead to undesired responses of anger, fear, or
resistance
 Since punishment only tells you what not to do, punishment combined with
reinforcement is usually more effective than punishment alone
Latent Learning – OC
 Although Skinner did not believe that
cognitive processes have a place in
psychology, evidence of cognition has
come from studying rats in mazes
 While exploring a maze with no obvious
reward, the rats seem to develop a
cognitive map: a mental representation of
the layout of one’s environment, of the
maze
Latent Learning - OC
 Then, when a reward is placed in the maze’s
goal box, the rats perform as well as rats that
have been reinforced with food for running
the maze
 During their explorations, the rats seemingly
experience latent learning: learning that
occurs but is not apparent until there is an
incentive to demonstrate it
 Learning can occur without reinforcement or
punishment, and there is cognition
Overjustification - OC
 The power of rewards can sometimes be detrimental
 Overjustification effect: the effect of promising a reward for doing what one
already likes to do; the person may now see the reward, rather than the intrinsic
interest, as the motivation for performing the task
 Overjustification with excessive rewards can undermine intrinsic motivation: the
desire to perform a behavior for its own sake and to be effective
 Extrinsic motivation: a desire to perform a behavior due to promised rewards or
threats of punishment
 A person’s natural interest usually survives when a reward is used neither to bribe
not to control, but to signal a job well done
Biological Predispositions
 In both Operant and Classical Conditioning, learning can only occur to the
extent of the species’ biological predispositions
 Pigeons can easily learn to flap their wings to avoid being shocked and to peck to obtain food,
but they have a hard time learning to peck in order to avoid a shock or to flap their wings and
eat with their beaks
 Biological constraints predispose organisms to learn associations that are naturally
adaptive
Observational Learning
 Among higher animals, especially humans,
learning need not occur through direct
experience
 The process of observing and imitating a
specific behavior is called modeling
 Social behaviors such as our catch-phrases,
ceremonies, foods, traditions, and fads all
spread by one person copying another
Observational Learning
 Recently, neuroscientists have discovered mirror neurons: frontal lobe neurons
that fire when performing certain actions or when observing another doing so
 The brain’s mirroring of another’s action may enable imitation, language
learning, and empathy
 The imitation of models shapes a child’s development
 Shortly after birth – an infant may imitate an adult who sticks out his tongue
 9 months – infants will imitate novel play behaviors
 14 months – infants will imitate acts modeled on tv
Albert Bandura’s Experiments
 A preschool child is coloring in a room when he sees an adult on the other side of the
room get up and kick, pound, and throw a large inflated Bobo doll around the room
 After observing this outburst, the child is taken to another room with appealing toys and
then told these good toys were for other children
 Then, the frustrated child is taken to another room with a few toys, including a Bobo doll
 Those who observed the adult’s outburst, when compared to those who did not, were
more likely to lash out at the doll
Bandura’s Bobo Doll Experiment
Observational Learning
 What determines whether we will imitate a model?
 Reinforcements and punishments
 We watch to learn and anticipate a behavior’s consequences in situations like those we are
observing
 Antisocial behavior such as family abuse can be passed on to younger
generations who regularly observe violence in the home
 On the other hand, prosocial behavior: positive, constructive, helpful behavior;
can prompt similar behavior in others
 Ex: Mahatma Gandhi and Martin Luther King Jr.
 Models are most effective when their actions and words are consistent
Television and Observational Learning
 Does viewing more violent programs on TV lead to people committing more
violent crimes?
 Although those who watch more TV are more likely to commit crimes, correlation
does not imply causation; maybe aggressive children prefer violent programs.
 However, prolonged exposure to violence can desensitize viewers.
Memory
 Memory: the persistence of learning over time through the storage and retrieval
of information
 Studying memory’s extremes has helped researchers understand how memory
works
 Your memory capacity is perhaps most apparent in your recall of flashbulb
memories: clear memories of an emotionally significant moment or event
 Ex: most people can recall where they were when they heard the news of 9/11
Information Processing
 Our memory is in some ways like a computer system’s information processing
system
 To remember any event requires that we get information into our brain
(encoding), retain that information (storage), and later get it back out (retrieval)
 Our memories are less literal and more fragile than a computer’s
Atkinson-Shiffrin’s Three Stage Processing
Model of Memory
 According to Richard Atkinson and Richard Shiffrin, we first record to-beremembered info as a fleeting sensory memory, from which it is processed into a
short-term memory bin, where we encode it for long-term memory and later
retrieval
1. Sensory memory: the immediate, initial recording of sensory information in the
memory system
2. Short-term memory: activated memory that holds a few items briefly before the
information is stored or forgotten
3. Long-term memory: the relatively permanent and limitless storehouse of the
memory system
 However, this process is limited and fallible
Working Memory
 The newer concept of working memory clarifies the short-term memory concept
by focusing more on how we attend to, rehearse, and manipulate information in
temporary storage
 Working memory integrates information coming in with that retrieved from longterm storage
 Includes a visual and a verbal component
Encoding
 Automatic processing: unconscious encoding of incidental information, such as
space, time, and frequency, and of well-learned information, such as word
meanings; difficult to shut off
 Effortful processing: encoding that requires attention and conscious effort
 We can boost our memory through rehearsal: the conscious repetition of information,
either to maintain it in consciousness or to encode it for storage