Definition of learning. Modules Learning. Vocabulary. Classical Conditioning Operant Conditioning Learning by Observation

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1 Modules Learning Classical Conditioning Operant Conditioning Learning by Observation Vocabulary Stimulus (Plural: Stimuli): an agent (as an environmental change) that directly influences the activity of a living organism or one of its parts Response: The behavior or cognitive process that occurs in reaction to a stimulus Definition of learning Learning is a relatively permanent change in behavior, or behavior potential, that occurs as the result of practice or experience. Produced by experience: not changes that result from maturation (neuromuscular development). Learning often takes place without immediately being shown in behavior and the learned behavior may be performed when there is an incentive to perform the behavior.

2 Learning Unlike most animals, we do not have a genetic blueprint for life. E.g., migrating birds know where they are supposed to go and how to go Much of what we do we learn from experience. Learning is our way of adapting to our environment We learn by association We (and virtually all organisms) naturally connect events that occur in sequence Associative Learning: learning that two events occur together two stimuli a response and its consequences Conditioning is the process of learning associations. Learning 1. Classical (or Pavlovian) conditioning Associate two stimuli E.g. lightning and thunder E.g. mosquito buzz and itching 2. Operant conditioning Associate a response and its consequence: repeat acts followed by rewards and avoid acts followed by punishments 3. Observational learning We learn from others experiences and examples (e.g., a child modeling his father dealing with frustration) In all these ways of learning, we adapt to our environments.

3 Module 18: Classical Conditioning A basic form of learning associations Behaviorism (Watson) An approach to psychology that emphasizes: That psychology should be an objective science. That psychology should concern itself ONLY with studying observable behaviors. That psychology should not be concerned with studying mental processes. A lot of what we know about learning was first studied by behaviorists. Classical Conditioning Ivan Pavlov Russian physiologist Nobel prize winner Conditioning was just an accident: dogs salivating before food was given

4 Classical Conditioning Pavlov s device for recording salivation Pavlov s Classic Experiment Classical Conditioning: Terminology Unconditioned Stimulus (US or UCS) stimulus that unconditionally--automatically and naturally--triggers a response Unconditioned Response (UR or UCR) Non-learned, naturally occurring response to the unconditioned stimulus salivation when food is present

5 Classical Conditioning: Terminology Conditioned Stimulus (CS) originally irrelevant (neutral) stimulus that, after association with an unconditioned stimulus, comes to trigger a specific conditioned response Conditioned Response (CR) learned response to a previously neutral conditioned stimulus (e.g., salivating to tone after learning) Classical Conditioning Organism associates two stimuli A neutral stimulus that signals an unconditioned stimulus begins to produce a response that is reserved for the unconditioned stimulus Conditioning Process

6 Conditioning Process Conditioning Process Note! Conditioning Process Note! And Note this too!

7 Birds An MIT student spent an entire summer going to the Harvard football field every day wearing a black and white striped shirt (referee shirt), walking up and down the field for ten or fifteen minutes throwing bird seed all over the field, blowing a whistle and then walking off the field. At the end of the summer, it came time for the first Harvard home football game, the referee walked onto the field and blew the whistle, and the game had to be delayed for a half hour to wait for the birds to get off of the field. The guy wrote his thesis on this, and graduated. Processes of Conditioning Acquisition Extinction Spontaneous Recovery Stimulus Generalization/ Discrimination Acquisition the initial stage in classical conditioning the phase associating a neutral stimulus with an US so that the neutral stimulus comes to elicit a conditioned response

8 Timing of CS before UCS Extinction diminishing of a CR in classical conditioning, when a US does not follow a CS E.g., ring the bell but do not present the food less and less salivation when done repeatedly, The learned association will become weaker and weaker... Spontaneous recovery Reappearance, after a rest period, of an extinguished CR

9 Classical Conditioning Generalization tendency for stimuli similar to CS to elicit similar responses Can be adaptive- as children taught to fear moving cars on street to respond similarly to trucks and motorcycles on the street Discrimination in classical conditioning, the learned ability to distinguish between a CS and other stimuli that do not signal a US E.g., fear pitbulls but not golden retrievers Lightning but not flashing disco lights Updating Pavlov s understanding Role of mental processes Thought/expectation of the CS-US link matters for conditioning Consistent link between the CS and US matters Role of biological dispositions Each species biological dispositions prepare it to learn the associations that enhance its survival Taste aversion (rather than sight) in rats - they are biologically prepared to learn associations between the taste of a particular food and the onset of an illness, but not between sights and sounds and an illness. Conditioned Taste Aversion If a flavor is followed by an illness experience, animals will avoid the flavor in the future CS + UCS > UCR Taste Toxic event Nausea CS -----> CR Taste Nausea Any real life applications? Quitting smoking

10 Nausea Conditioning in Patients US (drug) CS (waiting room) CS (waiting room) UR (nausea) US (drug) CR (nausea) UR (nausea) Classical Conditioning: Key Points Can explain a wide range of behavior Advertising, food aversion, phobias Focuses on naturally occurring behavior Any naturally occurring behavior (or response) can be conditioned to neutral stimulus Eye blink bell Sexual arousal strawberries