Basic Processes of Learning Chapter 4 Principles of

Basic Processes of Learning Chapter 4

Principles of Learning The environment is always fluctuating LEARNING: the process or set of processes through which sensory experience at one time can affect an individual’s behavior at a future time Experience: any effects in the environment that are mediated by the individual’s sensory systems

Classical Conditioning: Part I � Classical conditioning is a learning process that creates new reflexes REFLEX: a simple, relatively automatic, stimulus-response sequence mediated by the nervous system Stimulus Tap on the knee Nervous system • Nerves • Spinal Cord Response Leg jerks forward HABITUATION: the decline in the magnitude or likelihood of a reflexive response that occurs when the stimulus is repeated several times in succession

Pavlov’s Discovery Ivan Pavlov (1849 -1936) Studied the reflexes involved in digestion Could some other stimulus be triggering the salivating response in dogs?

Classical Conditioning

Extinction and Recovery from Extinction EXTINCTION • The gradual disappearance of a conditioned reflex that results when the CS occurs repeatedly without the UCS SPONTANEOUS RECOVERY • The return-due to the passage of time with no further testing or training-of a CR that had previously undergone extinction

Extinction and Spontaneous Recovery

Generalization and Discrimination Generalization • The phenomenon by which a stimulus that resembles a CS will elicit the CR even though is has never been paired with the UCS Discrimination Training • Procedure by which generalization between two stimuli is diminished or abolished by reinforcing the response to one stimulus and extinguishing the response to the other

Classical Conditioning and Behaviorism � BEHAVIORISM: (early 20 th century) school of psychological thought that holds the proper subject of study is observable behavior, not the mind � Behavior should be studied through an environmental context, not an internal, individualistic context � John B. Watson

Poor Little Albert… https: //www. youtube. com/watch? v=K 2 f. VYk. Bb. A 88

“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 beggarman and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors. (1930)” John Watson

Have you been classically conditioned? � Latch-key incontinence � Urinating and running water � Conditioned nausea

Stimulus-stimulus associatons Pavlov’s Stimulus-Stimulus Theory CS • Bell Mental representation of UCS • Food Watson’s Stimulus-Response Theory UCS CR • Food • Salivation CS CR • Bell • Salivation CR • Salivation

Which theory is better? Robert Rescorla (1973) Rats ”freezing” in response to a loud sound. UCS UCR So, do the rats freeze in response to the light because they associate the light with the sound, or because they have created a new light-freeze association? Rescorla habituated the rats to the loud sound. Remember habituation? UCS CS CS CR If S-S theory is correct, habituated rats should no longer freeze to light. If S-R theory is correct, habituated rats will still freeze.

Learned Expectancy Rescorla (1998): Classical conditioning is not a stupid process by which the organism willy-nilly forms associations between any two stimuli that happen to co-occur. Rather, the organism is best seen as an information seeker…” Example: Food is associated with not only salivation but chewing, etc. However, this behavior is not elicited after conditioning (begging, tail-wagging is). Translation: The dog expects the food. 1. The CS must precede the UCS • Classical conditioning does not occur if the CS and UCS occur simultaneously or the CS follows the UCS 2. The CS must signal heightened probability of occurrence of the UCS • As the number of pairings increases, so does the strength of the association. Internal probability calculation? 3. Conditioning is ineffective when the animal already has a good predictor • The Blocking Effect – new stimulus presented with CS does not become a new CS.

Conditioned Fear, Hunger and Sexual Arousal FEAR • UCS: sudden, loud noises, loss of support • Helps to avoid dangerous situations HUNGER • UCS: smell, visual or auditory stimuli • The appetizer effect SEXUAL AROUSAL • CS: any kind of stimulus, really • Conditioning increases number of offspring

Conditioned Drug Reactions � Drugs have two effects: the main effect and a compensatory effect that stabilizes the body (seen in rats injected w/morphine in distinct environment) � Why is only the compensatory effect able to be conditioned? � DRUG TOLERANCE: the phenomenon by which a drug produces successively smaller physiological and behavioral effects, at any given dose, if it is taken repeatedly � Overdosing A Clockwork Orange

Operant Conditioning I � OPERANT CONDITIONING: a training or learning process by which the consequence of a behavior response affects the likelihood that the individual will produce the response again Edward Thorndike (1898) Cats in the puzzle box LAW OF EFFECT: Responses that produce a satisfying effect in a particular situation become more likely to occur again in that situation

Burrhus Frederic (“BF”) Skinner � Researched and popularized theory of operant conditioning � Skinner box � REINFORCER: any stimulus change that occurs after a response and tends to increase the likelihood that the response will be repeated � AWARENESS need not be involved! (thumb twitch, fine motor skills)

Principles of Reinforcement How do you establish the first response? � SHAPING: procedure in which successively closer approximations to the desired response are reinforced until the response finally occurs (we do this with people too!) � EXTINCTION: the decline in response rate that results when an operant response is no longer followed by a reinforcer

Schedules of Partial Reinforcement (vs. continuous reinforcement) Fixed-ratio schedule • A reinforcer occurs after every nth response, where n is some whole number greater than 1 Variable-ratio schedule • The number of responses required before reinforcement varies unpredictably around some average Fixed-interval schedule • A fixed period of time elapses between one reinforced response and the next Variable-interval schedule • The period of time that must elapse before a response will be reinforced varies unpredictably around some average

Reinforcement and Punishment Goal Positive (Introducing something) Negative (Removing something) Manipulation INCREASES TARGET BEHAVIOR Positive Reinforcement (Lever Press Food pellet) DECREASES TARGET BEHAVIOR Positive Punishment (Lever Press Shock) + Add something good + Add something bad Negative Reinforcement (Lever Press Shock off) Negative Punishment (Lever Press removes food) - Take away something bad - Take away something good

The Big Bang Theory https: //www. youtube. com/watch? v=JA 96 Fba-WHk

Operant Conditioning II Through discrimination training, an animal can be conditioned to make an operant response to a stimulus more specific than the entire inside of a Skinner Box. Discriminative stimulus GENERALIZATION

The Overjustification Effect � OVERJUSTIFICATION EFFECT: the phenomenon in which a person performing a task for no reward becomes less likely to perform that task for no reward after a period of time during which he or she has been rewarded for performing it � Cognitive consequences of rewards � Behavior Analysis (or Applied Behavior Analysis) Judge Rotenberg Educational Center (MA)

Facilitating Learning: PLAY � Exercise or activity for amusement or recreation; has no useful purpose � Karl Groos’ Theory of Play (1898): Practice species-typical behavior 1. the young play more than adults 2. Species that have the most to learn play the most 3. Play most at important skills 4. Involves repetition 5. Play is challenging � Play in humans: a form of imitation

Facilitating Learning: EXPLORATION: the investigation of unknown regions A more primitive form of learning A balance of curiosity and fear

Exploration: Information Acquisition � Tolman and Honzik (1930): Rewards affect what animals do more than what they learn � LATENT LEARNING: learning that is not demonstrated in the subject’s behavior at the time that the learning occurs but can be inferred from its effect on the subject’s behavior at some later time

Facilitating Learning: OBSERVATION � OBSERVATIONAL LEARNING: learning by watching others � Is it really imitation? � Stimulus enhancement: increase in the salience or attractiveness of the object that the observed individual is acting upon � Goal enhancement: an increased drive to obtain rewards similar to what the observed individual is receiving

Food-Aversion Learning What is safe to eat? Most animals learn to avoid foods that have made them ill Food aversion differs from classical conditioning because: A significant time delay CS must be a taste or smell Food Preference Learning Animals must also learn to choose foods that satisfy a nutritional requirement, can associate certain foods with improvement in health Humans have a preference for high-calorie foods: (evolutionary advantageous)