+ learning. + stimulus or stimuli any event or object in the environment to which an organism...

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Learning

+Stimulus or Stimuli

Any event or object in the environment to which an organism responds

+Learning

Relatively permanent change in behavior, knowledge, capability, or attitude acquired through experience & cannot be attributed to illness, injury, or maturation

Why injury? Like when your behavior may change because you’ve had a brain injury.

Why maturation? Like when you talk in a deeper voice as a result of puberty.

+Classical Conditioning

A stimulus comes to predict the occurrence of another stimulus and elicits a response similar to the response related by that stimulus.

A cat salivates when they see and smell their food; tap the can every time you are about to feed your cat & they will start to salivate when they hear the tapping.

+Ivan Pavlov (1849-1936)

Russian scientist, studied physiology of digestion, won Nobel Prize in 1904

Major contribution was the study of the conditioned reflex, which provided a model of learning called classical conditioning

Used dogs & a bell

+Elements of Classical Conditioning

Reflex: an involuntary response to a particular stimulus (eyeblink, salivation)

2 kinds of reflexes: conditioned & unconditioned OR learned & unlearned

Unconditioned response (UR): response that is invariably elicited by the US without prior learning

Unconditioned stimulus (US): elicits a specific response without prior learning

Conditioned stimulus (CS): neutral stimulus after repeated pairing becomes associated with & elicits a conditioned response

Conditioned response (CR): response that comes to be elicited by a conditioned stimulus as a result of repeated pairing with US

Elements Stimulus & Response

+Extinction & Spontaneous Recovery

Extinction: weakening & eventual disappearance of a learned response

Spontaneous recovery: reappearance of an extinguished response

+Generalization

In classical conditioning, the tendency to make a conditioned response to a stimulus similar to the original conditioned stimulus

+Discrimination

Learned ability to distinguish between similar stimuli so the conditioned response occurs only to the original conditioned stimulus but not the similar stimuli

+Higher Order Conditioning

Conditioning that occurs when a neutral stimulus is paired with an existing conditioned stimulus, becomes associated with it, and gains the power to elicit the same conditioned response

For example, Pavlov could flash a light along with the tone he played & then the light flashing would also become associated with the stimulus

+John Watson (1878-1958)

Demonstrated that fear could be classically conditioned by presenting a white rat along with a loud, frightening noise, thereby conditioning Little Albert to fear the white rat.

Fear generalized to a dog, a seal coat, Watson’s hair, and a Santa Claus mask

Formulated techniques to remove a conditioned fear

+Classical Conditioning: Modern View

Rescorla: predicting the occurrence of the unconditioned stimulus

Rat experiment: tone (CS) & shock (US) = predict response BUT tone (CS) & shock (US) AND no shock (US) = not predictable response

+Blocking

When previous conditioning to one stimulus prevents conditioning to a second stimulus with which it has been paired

Tone (CS), then Light (CS), but tone “trumped” CR because it was learned first, light (CS) was “blocked”

+Taste Aversions

Intense dislike and/or avoidance of a particular food that have been associated with pain or discomfort

Can be generalized

Chemotherapy: “scapegoat” food before treatment

+Everyday Classical Conditioning

Many emotional responses result from classical conditioning (positive and negative)

Fears & Phobias / dentist’s office

Drug Use / cues / soldiers & heroin use in Vietnam

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+Factors Influencing Classical Conditioning

How reliable a conditioned stimulus predicts the unconditioned response

The number of pairings of the conditioned stimulus and the unconditioned stimulus

Intensity of the unconditioned stimulus

Temporal relationship between the conditioned stimulus and the unconditioned stimulus

+Operant Conditioning

The consequences of behavior are manipulated in order to increase or decrease that behavior in the future.

Voluntary responses (not reflexive)

Active state

Simple to highly complex responses

+Thorndike & the Law of Effect

Edward Thorndike (1874-1949)

Trial-and-error learning: occurs when a response is associated with a successful solution to a problem after a number of unsuccessful responses.

Cats in the puzzle box, hitting lever for food

Law of effect: connection between a stimulus & response will be strengthened if the response is followed by a satisfying consequence or weakened it causes discomfort.

+B.F. Skinner: Operant Conditioning Pioneer

Burrhus Frederic Skinner (1904-1990)

Believed behavior was shaped by the environment

Response first, then consequence

Skinner box: soundproof chamber with a device for delivering food & either a bar for rats to press or a disk for pigeons to peck

+Shaping

An operant conditioning technique that consists of gradually molding a desired behavior (response) by reinforcing responses that become progressively closer to it

+Extinction

Weakening & often eventual disappearance of a learned response (in operant conditioning, the conditioned response is weakened by withholding reinforcement)

+Generalization

In operant conditioning, the tendency to make the learned response to a stimulus similar to the one that was originally reinforced

+Discriminative stimulus

A stimulus that signals whether a certain response or behavior is likely to be followed by reward or punishment

+Reinforcement

An event that follows a response and increases the strength of the response and/or the likelihood that it will be repeated

+Positive Reinforcement

A reward or pleasant consequence that follows a response and increases the probability that the response will be repeated

+Negative Reinforcement

The termination of an unpleasant stimulus after a response in order to increase the probability that the response will be repeated

+Primary Reinforcer

A reinforcer that fulfills a basic physical need for survival & does not depend on learning

Eating, sleeping, drinking, stopping pain, & having sex

+Secondary Reinforcer

A neutral stimulus that becomes reinforcing after repeated pairings with other reinforcers

Money, praise, good grades, attention, approval

+Continuous Reinforcement

Administered after every desired or correct response; the most effective method of conditioning a new response

Rat got food every time it pressed bar

+Partial Reinforcement

Pattern of reinforcement in which some portion, rather than 100%, of the correct responses are reinforced

More like real life, partial reinforcement is the rule

+Schedule of Reinforcement

Systematic program for administering reinforcements that has a predictable effect on behavior

Distinct rates & patterns of responses

+Fixed-Ratio Schedule

A fixed number of correct responses

Rat receives food after 5 pushes of lever

What would happen if the ratio was 100 pushes for each pellet of food?

If it was 1,000?

+Variable-Ratio Schedule

Reinforcer is given after a varying number of nonreinforced responses based on an average ratio

Rat gets food after 30 lever pushes, then 20 pushes, then 50… averages to VR of 30

Higher, more stable rates of responding than fixed-ratio schedules

+Variable-Ratio Schedule

Real life example: Casino gambling

Variable-ratio: highest response rate & most resistance to extinction

+Fixed-Interval Schedule

Reinforcer is given following the first correct response after a fixed period of time has elapsed

Working on salary: fixed-interval schedule

Food given every 60 seconds

+Variable-Interval Schedule

Reinforcer is given after the first correct response following a varying time of nonreinforcement based on an average time.

Pop quizzes, cannot predict, so study responses should be more uniform

+Partial Reinforcement Effect

Greater resistance to extinction

Reward not expected every time, so the learning does not become extinct

Strongest resistance to extinction observed by Holland & Skinner (1961): Fixed ratio of 900, pigeon emitted 73,000 responses during the first 4 ½ hours of extinction

Why parents should not give into nagging.

+Influencers in Operant Conditioning

Magnitude

Immediacy

Level of motivation of the learner

+Punishment vs. Negative Reinforcement

Punishment: adds a negative condition

Reinforcement: removes a negative condition

Punishment: Discourages a behavior

Reinforcement: Encourages a behavior

+Problems with punishment

Does not extinguish undesirable behavior, it suppresses that behavior when they are being punished

Does not help people develop more appropriate behaviors

Often causes fear & anger

Can lead to aggression

+Effective Punishments

Timing

Intensity

Consistency

+Escape & Avoidance Learning

Escape learning: performing a behavior because it terminates an aversive event (running away, taking medicine)

Avoidance learning: first, an event signals a bad situation (classical conditioning); second, you avoid that situation (operant conditioning, negative reinforcement)

+Learned Helplessness

A passive resignation to aversive conditions learned by repeated exposure to aversive events that are inescapable and unavoidable

Dogs; abused women

+Applications

Training Animals

Biofeedback

Behavior modification

+Learning by Insight: Aha!

Wolfgang Köhler (1887-1967)

Chimps, bananas, sticks, boxes & a flash of insight (not trial-and-error)

Solution gained through insight is more easily learned, less likely forgotten & more readily applied to new problems

+Latent Learning & Cognitive Maps

Edward Tolman (1886-1959)

Latent learning: occurs without apparent reinforcement but is not demonstrated until sufficient reinforcement is provided

Rats, mazes, one rewarded, one not, one rewarded later.

Cognitive map: mental representation of a spatial arrangement

+Observational Learning

Albert Bandura (1925-present)

Observational learning or modeling: learning by watching the behavior of others & the consequences of that behavior; learning by imitation

Fears acquired by observing behavior

Aggression acquired by observation