PSY 402. Theories of Learning Chapter 1 What is Learning?

Transcription

1 PSY 402 Theories of Learning Chapter 1 What is Learning?

2 What is Learning? Learning is: An experiential process Resulting in a relatively permanent change Not explained by temporary states, maturation, or innate response tendencies.

3 Three Limits on the Definition The change that occurs during learning is a potential for behavior that depends on other conditions. Learning is not always a permanent change. What can be learned can be unlearned. Changes also occur for other reasons maturation, motivation.

4 Three Kinds of Learning Adaptation to the environment Habituation & sensitization Classical conditioning Also known as Pavlovian conditioning, respondent conditioning, S-S learning. Instrumental or operant conditioning Also known as S-R learning.

5 Roots of Learning Theory The discovery of reflexes Functionalism British Associationists

6 1.3 (A) René Descartes; (B) René Descartes came up with the concept of reflex action

7 Man, the Machine Descartes proposed that the body operates mechanically via reflex actions, similar to machinery. Reflexes are activated by stimuli in the environment. A reflex connects a stimulus (S) with a response (R). This concept is used throughout learning theory.

8 The Role of Mind Descartes proposed that the mind could overrule the action of bodily reflexes. Hobbes disagreed, arguing that the mind too operated reflexively. Hedonism all human thought is governed by seeking pleasure and avoiding pain. De la Mettrie observed that humans and animals are similar, and the body can affect the mind, as well as vice versa.

9 1.4 Two famous British Empiricists John Locke David Hume

10 British Empiricists (Associationists) Locke, Hume, Berkeley The mind is a blank slate (tabula rasa) at birth. Knowledge is built up from sense impressions combined to form complex ideas. Associations bind these impressions together. Complexity is built from simple parts Example of the apple sweetness, redness, roundness, associated with taste, smell to form the idea (concept) of an apple.

11 1.5 Immanuel Kant

12 Nature vs. nurture Nativists (nature) vs. empiricists (nurture). Rationalism Kant argued that the mind is prepared to respond to its environment at birth. A priori assumptions or ideas organize experience. We are born knowing about causality, substance, and a variety of other concepts. This idea is called preparedness. The extreme version of this philosophy is called structuralism.

13 1.6 (A) Charles Darwin; (B) Drawing from one of Darwin s notebooks

14 Evolution & Natural Selection Darwin there is a continuity between humans and animals and both struggle for survival. Perhaps the mind itself has evolved. Functionalism because behavior promotes survival, we can study behavior to understand its adaptive function.

15 Functionalists Dewey lower animals have reflexes, humans have a flexible mind James people have instincts, not reflexes The difference is whether the behavior can be changed or interrupted Brucke internal biochemical forces motivate behavior in all species.

16 Criticisms of Functionalism The variety of behavior across cultures is inconsistent with universal human instincts. Infants seem to have few innate instincts. Labeling everything an instinct doesn t aid understanding much. Bernard cataloged instincts

17 Comparative Psychology Romanes collected stories of animal behavior. Morgan observed that dogs were not as clever as humans in performing certain tasks. Complex animal behaviors may be built from laboriously learned simple processes. We cannot judge from the observed result but from the process of learning. Morgan s canon behavior should not be explained by a complex process if a simpler one works (parsimony of explanation).

18 1.7 (A) C. Lloyd Morgan; (B) Morgan s dog, Tony

19 Behaviorism A search for the laws governing learning. Emphasis on experience. Avoidance of mentalistic concepts. Associations are formed based on: Resemblance (similarity) Contiguity in time or place Cause and effect We can generalize from animals to humans.

20 Early Experiments Thorndike S-R learning with cats in puzzle box. Pavlov S-S learning with dogs salivating for meat powder. Watson S-S learning with humans, such as Little Albert and the white rabbit. Skinner S-R learning with rats in Skinner boxes (operant chambers). A radical Behaviorist. Tolman the gadfly of Behaviorism, arguing that even rats have minds and think about their actions.

21 1.8 (A) Edward Thorndike; (B) Two puzzle boxes Thorndike used to study the intelligence of cats

22 Thorndike s Laws Also called S-R learning. Law of effect A chance act becomes a learned behavior when a connection is formed between a stimulus (S) and a response (R) that is rewarded. Law of exercise the S-R connection is strengthened by use and weakened with disuse.

23 Thorndike s Laws (Cont.) Law of readiness motivation is needed to develop an association or display changed behavior. Associative shifting a learned behavior (response) can be shifted from one stimulus to another. Once a behavior is learned, the stimulus is gradually changed. Fish + stand up, then stand up alone.

24 1.9 (A) Ivan Pavlov; (B) Pavlov s classical conditioning set-up

25 Pavlov s Conditioned Reflex Conditioning -- a stimulus that initially produces no response can acquire the ability to produce one. Learning occurs through pairing in time and place of one stimulus with another stimulus that produces a response. This is a kind of associative shifting, but the response is involuntary.

26 Pavlov s Studies

27 1.10 John B. Watson

28 Watson & Raynor Human fears can be acquired through Pavlovian (classical) conditioning. Rat paired with loud noise Stimulus generalized to other white objects (white rabbit, white fur coat) Mary Cover Jones developed counterconditioning -- a technique for eliminating conditioned fears. Acquisition of fear-inhibiting response

29 Little Albert

30 1.11 (A) B. F. Skinner; (B) A modern Skinner box

31 Ethics of Learning Research Animals and humans are now protected by oversight and ethical guidelines. Pain or injury to animals must be weighed against and justified by the knowledge to be gained. Electric shock typically is uncomfortable and upsetting but not physically harmful.

32 The Operant vs Respondent Distinction How voluntary is behavior? Operant vs respondent distinction: Respondent behavior is controlled by what happens first (antecedents), elicited by stimuli in the environment. Operant behavior is controlled by the consequences of behavior in the past, emitted by the organism based on prior experience.

33 1.12 Edward C. Tolman developed operational behaviorism

34 Tolman s Operational Behaviorism Tolman proposed that behavior can be described in terms of unobservable mental constructs. Thirst is a construct that relates antecedents to observed behavioral responses. Constructs are widely used in psychology. Cognitive psychology emerged out of Tolman s early research demonstrating constructs in rats.

35 1.13 A theoretical construct like thirst is not directly observable (Part 1)

36 1.13 A theoretical construct like thirst is not directly observable (Part 2)