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