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LEARNING

Introduction

Adaptability – our capacity to learn new behaviors that help us cope with changing circumstances

May be humans most important characteristic

Learning – a relatively permanent change in an organism’s behavior due to experience

Introduction

Three types of learning:

Classical Conditioning

Operant Conditioning

Observational Learning

Aristotle, Locke, and David

Hume all agree:

“We learn by association”

Our minds naturally connect events that occur in sequence

How Do We Learn?

Behaviors can also become associated with contexts

Example: we may crave popcorn when we enter a Theatre

Example: some people only smoke when they are drinking

Associative Learning – learning that certain events occur together

Thunder and lightning

Christmas and presents

How Do We Learn?

Conditioning – process by which we learn associations

Classical Conditioning – a type of learning in which one learns to link two or more stimuli and anticipate events

Example: Pavlov’s tuning fork and meat powder both announce the presence of food

How Do We Learn?

Operant Conditioning – a type of learning where one learns to associate a

response (our behavior) and

its consequence and thus to repeat acts followed by good results and avoid acts followed by bad results

Example: a seal receives a treat (fish) each time it successfully balances a ball on it’s nose

How Do We Learn?

Observational Learning – a type of learning where we learn from others’ experiences

Example: if the first ten people that finish taking a test get a treat, test takers will work more quickly to attain the treat

Example: checking if there is electric in a cattle fence

Classical Conditioning

Ivan Pavlov (1849-1936) – responsible for the development of classical conditioning

Russian who studied digestive system

Won Russia’s first Nobel prize in 1904

Studied salivation habits of dogs

Paired “neutral” events with food in dog’s mouth

Classical Conditioning

John B. Watson (1913) – said psychology should be an objective science based on observable behavior

“Behaviorism” – shaped N.

American psychology during first half of 20 th century

Classical Conditioning

Unconditioned

Not trained/learned

Happens naturally

Unlearned

Conditioned

Trained

Learned

Doesn’t happen naturally

Classical Conditioning

Stimulus – something that elicits a response

Response – a behavior that happens as a result of a stimulus

Example:

Stimulus = Loud Noise

Response = Flinching

Classical Conditioning

Unconditioned Stimulus (US) – a stimulus that unconditionally

(naturally and automatically) triggers a response

Ex: food in mouth

Classical Conditioning

Conditioned Stimulus (CS) – an originally irrelevant stimulus that, after association with a

US, comes to trigger a CR

Ex: Sound of a tone

Unconditioned Response (UR)

– the unlearned, naturally occurring response to a US

Ex: salivation when food is in mouth

Conditioned Response (CR) – the learned response to a previously neutral (but now conditioned) stimulus (CS)

Ex: salivation to sound of a tone

Conditioning Processes

Pavlov worked on the following processes for 30 years:

_________________________

Acquisition

Extinction

Spontaneous Recovery

Generalization

Discrimination

Conditioning

Acquisition: in classical conditioning, the initial stage, when one links a neutral stimulus and an unconditioned stimulus so that the neutral stimulus begins triggering the conditioned response; in operant conditioning, the strengthening of a reinforced response

Acquisition

How much time should elapse between presenting the neutral stimulus (tone, light, touch) and the unconditioned stimulus?

About ½ second works well

Order is important

If US appeared before the CS, conditioning probably would not happen

Acquisition

Conditioning helps animals survive and reproduce

Higher-Order Conditioning – also called Second-Order

Conditioning, a new neutral stimulus can become a new conditioned stimulus

Tends to be weaker

Ex. – when a tone predicts food and a light precedes the tone, animal may learn that the light predicts food and respond to light

Extinction & Spontaneous Rec.

Extinction – in C.C. the diminishing of a conditioned response (CR)

– happens when an (US-food) does not follow a (CS-tone) in O.C. happens when a response is no longer reinforced

Extinction & Spontaneous Rec.

Spontaneous Recovery – the reappearance, after a pause, of an extinguished conditioned response (CR)

Ex. – dog begins to respond to tone again

Discrimination – in C.C. the learned ability to distinguish between a conditioned stimulus and stimuli that do not signal an unconditioned stimulus

Ex. – dog knows difference between bell and tuning fork

Extending Pavlov

Pavlov and Watson – underestimated the importance of cognitive

processes (thoughts, perceptions, expectations) and biological constraints on an organism’s learning capacity

Cognitive Processes

Robert Rescorla & Allan

Wagner (1972) – showed animals can learn the predictability of an event

Presented a light, then tone, then shock

Rats did not respond with fear to the light; the tone was met with fear

The more predictable the association, the stronger CR; animal learns expectancy

Biological Predispositions

Gregory Kimble (1981) – said an animals capacity for conditioning is constrained by its biology; each species’ predispositions prepare it to learn the associations that enhance its survival

Biological Predispositions

John Garcia – challenged idea that all associations can be learned equally well

First did radiation tests on rats in 1960s; rats weren’t drinking water from plastic bottles anymore

Thought rats may have linked plastic-tasting water (CS) to the sickness (UR) triggered by radiation (US)

Biological Predispositions

Garcia’s Findings:

Even if sickened several hours after tasting a novel flavor, rats would thereafter avoid the flavor

Sickened rats developed aversions to tastes, but NOT to sights or sounds

Contradicted idea that US must immediately follow CS; makes adaptive sense for rats being they use taste to identify food

Biological Predispositions

Another Garcia Study:

Coyotes and Wolves were tempted into eating sheep carcasses laced with poison

Both developed an aversion to eating sheep meat

Eventually wolves penned with a live sheep learned to fear the sheep

Learning enables animals to adapt to their environments

(taste aversions help animals to survive)

Pavlov’s Legacy

By today’s standards,

Pavlov’s ideas were correct, but incomplete

Pavlov’s Legacy

Pavlov showed us how a process such as learning can be studied objectively

Relevance today: classical conditioning is one way that virtually ALL organisms learn to adapt to their environment

Applications of Classical

Conditioning

Former drug users often feel a craving when they are again in a drug-using

context

When a certain taste accompanies a drug that influences an immune response, the taste by itself can come to trigger the same immune response

Applications of Classical

Conditioning

Watson (1913) had idea that human emotions and behaviors are mainly a bundle of conditioned responses.

Watson and Rosalie Raynor worked with 11-month-old

“Little Albert” to test how specific fears may be conditioned

Applications of Classical

Conditioning

“Little Albert” Study

Initially Albert feared loud noises but not white rats

In experiment, when Albert reached for white rat a loud noise was presented

After several trials, Albert cried at the sight of the rat

5 days later, Albert showed generalization by showing fear toward a rabbit, dog, etc. but not dissimilar objects

Applications of Classical

Conditioning

Watson ended up marrying

Raynor and he worked for

Maxwell House coffee, helping to introduce the

“coffee break” as an

American custom

Man who feared elevators cured his fear by making himself take elevators 20 times per day (conditioning)

Watson’s Classic Boast:

“Give me a dozen healthy infants, well-formed, and my own specified world to bring them up in and I’ll guarantee to take any one at random and train him to become any type of specialist I might select doctor, lawyer, artist, merchant-chief, and, yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors.”

-John B. Watson

Classical Conditioning

Classical conditioning forms associations between two stimuli; involves

respondent behavior, actions that are automatic responses to a stimulus

Operant Conditioning

In Operant conditioning, organisms associate own actions with consequences; actions followed by reinforcers increase; actions followed by punishers decrease.

Called “operant” because it is behavior that operates on the

environment to produce rewarding or punishing stimuli

Skinner’s Experiments

B.F. Skinner (1904-1990)

Edward L. Thorndike (1874-1949)

Thorndike’s Law of Effect: rewarded behavior is likely to recur

Skinner trained pigeons to:

Walk a figure 8

Play ping-pong

Keep a missile on course

Skinner’s Experiments

Thorndike trained cats to find their way out of a

“puzzle box”

Skinner created an “operant chamber” also known as a

“Skinner box”

Such a box contains an animal and has a bar or key to press or peck to release a reward of food or water; it also has a device that records responses

Shaping Behavior

Shaping – in operant conditioning, reinforcers guide behavior toward closer and closer approximations of the desired behavior

It is important to first watch how the animal naturally behaves, and then build on existing behaviors

Example: We can’t shape an elephant to jump rope

Shaping Behavior

Giant rats have been shaped to sniff out land mines in Mozambique

Pigeons have been shaped to recognize human faces among other stimuli

Among humans, whining is reinforced when we react to it – a whining child eventually gets attention

Types of Reinforcers

Reinforcer – in O.C. any event that strengthens

(increases frequency of) the behavior it follows

Examples include food, money, praise, attention, being yelled at, borrowing the car, etc.

What is reinforcing to one person may NOT be to the next

Types of Reinforcers

Positive Reinforcement

Strengthens a response

Presents a typically pleasurable stimulus

Negative Reinforcement

Strengthens a response

Reduces or removes something undesirable or unpleasant

Negative reinforcement is NOT the same as punishment

Negative reinforcement removes a “punishing” event

Types of Reinforcers

Primary Reinforcers – an innately reinforcing stimuli; one that satisfies a biological need

Getting food when hungry

Having a headache go away

Types of Reinforcers

Conditioned Reinforcers – also called Secondary

Reinforcers – gains its reinforcing power through association with primary reinforcer

When a light signals food is coming, the rat will work to turn on the light

Types of Reinforcers

Rats will not learn to respond if delay between behavior and reinforcement is more than 30 seconds

Humans DO respond – it’s called “delayed gratification”

Examples: paycheck at end of month, grades at end of Tri, trophy at end of season

Types of Reinforcers

Continuous Reinforcement

– reinforcing desired response every time it occurs

Partial (Intermittent)

Reinforcement – reinforcing desired response only part of the time; slower acquisition, but greater resistance to extinction

Reinforcement Schedules

Real life rarely provides continuous reinforcement

Partial Reinforcement examples:

Fishing – don’t get a fish every cast

Sales – don’t make a sale to every prospective consumer

Slot Machines – reward gamblers occasionally and unpredictably

Reinforcement Schedules

Partial Reinforcement

(Cont’d):

Occasionally giving in to a child’s tantrums is perfect way to reinforce that behavior; this will make the behavior persist

Reinforcement Schedules

Fixed-ratio

Reinforces behavior after a set # of responses

Ex: get a free coffee after you buy 10

High rate of responding

Variable-ratio

Reinforces behavior after unpredictable # of responses

Ex: slot machines and anglers

High rate of responding

Reinforcement Schedules

Fixed-interval

Reinforces the first response after a given time period

Ex: more frequently checking for the mail as delivery time nears

Produces choppy start-stop pattern of responding

Variable-interval

Reinforces the first response after varying time intervals

Ex: “You’ve got mail” after persistently checking email

Produces slow, steady responding

Punishment

Punishment – an event that decreases the behavior that it follows

Opposite of reinforcement, which increases the behavior it follows

Punishment

Studies show that criminal behavior, much of it impulsive, is not deterred by the threat of severe sentences

Increased patrols that ensured the swiftness of punishment lead to a drop in crime rate

Parenting and Punishment

1. Punished behavior is suppressed, not forgotten

-spanking a child for swearing may reinforce parents’ punishing behavior

2. Punishment teaches discrimination

-child doesn’t learn NOT to swear – just learns not to swear around parents

Parenting and Punishment

3. Punishment can teach fear

-child associates fear with undesired behavior, but also with person who delivers punishment or the place it occurred

4. Physical punishment may increase aggressiveness by modeling aggression as a way to cope with problems

Reinforcement & Punishment

Punishment tells you what not to do; reinforcement tells you what to do

What punishment often teaches…is how to avoid it

-Skinner

Today, reinforcement is a more emphasized approach

Extending Skinner’s

Understanding

Even though resisted by

Skinner, cognitive processes have a necessary place in science of psychology

Extending Skinner’s

Understanding

Rats seem to develop a

cognitive map of a maze, which suggests a cognitive process

Latent Learning – learning that becomes apparent only when there is some incentive to demonstrate it

Ex: rats quickly completing a before experienced maze when there is now food at end

Extending Skinner’s

Understanding

Excessive rewards can undermine intrinsic motivation (“it must not be worth doing for it’s own sake if I need to be rewarded for it”)

Motivation

Intrinsic Motivation – a desire to perform a behavior effectively for its own sake

Extrinsic Motivation – a desire to perform a behavior to receive promised rewards or avoid threatened punishment

Motivation

Giving people choices also enhances their intrinsic motivation

Rewards can be effective to signal a job well done; NOT to bribe or control

Biological Predispositions

An animals natural predispositions constrain its capacity for operant conditioning

Biological constraints predispose organisms to learn associations that are naturally adaptive

Biological Predispositions

Instinctive Drift – when animals revert to their biologically predisposed patterns

Skinner’s Legacy

Skinner said external influences (not internal thoughts and feelings) shape behavior

Skinner said we should use reward to evoke more desirable behavior; external consequence can help shape our future

Applications of Operant Cond.

At School

Teaching machines that immediately reinforce correct responses

Students must be immediately told whether what they do is right or wrong and, when right, they must be directed to the step to be taken next

Applications of Operant Cond.

In Sports

Golfers start with very short putts, eventually stepping further and further away

Batter begin with half swings at an oversized ball

Both examples resulted in faster skill improvement

Applications of Operant Cond.

At Work

Rewards are most likely to increase productivity if desired performance is welldefined and achievable

Reward specific, achievable behaviors, NOT vaguely defined merit

Reinforcement should be immediate

Applications of Operant Cond.

At Home

Notice people doing something right and affirm them for it; give children attention when they are behaving well

When a negative behavior is observed, don’t yell or hit.

Simply explain the misbehavior and give them a time-out

Applications of Operant Cond.

Self Improvement

State your goal

Monitor how often you engage in your desired behavior

Reinforce the desired behavior

Reduce the rewards gradually

Contrasting Classical & Operant

Conditioning

Similarities….

Both are forms of associative learning

Both involve acquisition, extinction, spontaneous recovery, generalization, and discrimination

Contrasting Classical & Operant

Conditioning

Differences…

Classical (Pavlovian) – organism associates different stimuli that it doesn’t control and responds automatically

(respondent behaviors)

Operant – organism associates its operant behaviors with consequences

Learning by Observation

Observational Learning – learning by observing others

Modeling – the process of observing and imitating a specific behavior

Learning by Observation

Children who often experience physical punishment tend to display more aggression

Mirrors in the Brain

Mirror Neurons – frontal lobe neurons that fire when performing certain actions or when observing another doing so; may enable imitation and empathy

In children, mirror neurons help in the development of a theory of mind

Make emotions contagious

Mirrors in the Brain

“Our brain’s mirror neurons underlie our intensely social nature.”

Empathy in the brain shows up in the emotional brain areas, but NOT in the somatosensory cortex, which receives the physical pain input

Bandura’s Experiments

Albert Bandura – pioneering researcher of observational learning

Known for famous Bobo

Doll experiment, where children imitated the behavior of observed adults

By watching, we learn to anticipate consequences

Applications of Observational

Learning

We look and we learn

Behavior modeling helps train communications, sales, and customer service skills

Prosocial Effects

Prosocial – positive, helpful behavior

Read with your children

If you want them to follow a religion, practice with them

Make actions and words consistent

Children learn by being told what to do, and watching what we do

Antisocial Effects

Antisocial – negative, nonhelpful behavior

Abusive parents may have aggressive children

Lessons learned as children are NOT easily unlearned as adults

On average, a 75 year old person in U.S. has spent 9 years watching T.V.

Antisocial Effects

Late 20 th

Century statistics on watching T.V.

Average child viewed 8000 TV murders, 100,000 acts of violence before finishing elementary school

60% of shows had violence

74% of violence in show went unpunished

58% didn’t show victim’s pain

“Violence viewing effect”

Antisocial Effects

Correlational studies DO support the link between violence viewing and violent behavior

Viewing cruelty to some extent causes people to act more cruelly

“Violence on television does lead to aggressive behavior by children”

Antisocial Effects

Imitation – children as young as 14 months will imitate acts they observe on

TV

Desensitized Viewers – prolonged exposure to violence leads to viewers becoming more indifferent to it when later viewing it

Antisocial Effects

Watching cruelty fosters indifference.

Children often imitate pro wrestlers

Review: Ivan Pavlov,

John Watson, B.F. Skinner,

Albert Bandura

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