Transcript LEARNING
1 LEARNING A DEFINITION OF LEARNING 2 A relatively permanent change in behaviour potential that results from experience. Learning verses performance Experience required Internal processes (behaviour is the manifestation) Learning reflects a change in the potential to behave. Motivation, maturation, illness, fatigue may cause changes in behaviour but this is not learning. Behavior changes that learning causes are not always permanent. New, competing behaviors, may be learned. HISTORICAL ORIGINS 3 Several schools of thought have contributed to the the study of learning processes. Functionalism Behaviourism Associative Cognitive Functionalism 4 Early school of thought in psychology that emphasized instinctive origins and adaptive function of behavior. Antecendents Dualism Darwin’s Natural Selection Descartes’ Dualism 5 “Man as part machine” René Descartes (1594-1660) Nonhuman 6 Stimulus Involuntary Action Human Stimulus Involuntary Action Voluntary Charles Darwin Natural variation Some characteristics are selected John Dewey 8 Father of functionalism Suggested that reflexive behaviors of lower animals had been replaced in humans by the mind In humans, the mind had evolved as the primary mechanism for survival Mind enables individual to adapt to environment 9 The main idea of Dewey’s functionalism was that the manner of human survival differs from that of lower animals. William James 10 Argued that the major difference between humans and lower animals is in the character of their inborn or instinctive motives Humans possess greater range of instincts that guide behavior than do lower animals These include “social” instincts, which directly enhance our interaction with the environment and our survival Instincts are both purposeful and directional 11 The concept of instincts was strongly criticized based on: Anthropological observation of differences in values, beliefs, and behaviors among cultures Widespread and uncritical use of the instinct concept did not advance the understanding of human behavior. 12 By the 1920’s, psychologists had moved away from the instinct explanation and began to emphasize the learning process. Psychologists who viewed experience as the major determinant of human actions were called Behaviorists 13 These criticisms lead to the Behavioral Revolution Behaviorism 14 School of thought that emphasizes the role of experience in governing behavior Behaviorists believed that the important processes governing behavior are learned Major goal of behaviorism was to the determine the laws governing learning 15 An important influence on Behaviorism came from Aristotle’s concept of Associationism Associationism 16 Aristotle was the earliest advocate of associationism. Aristotle’s associationism had an important influence on behaviorism. Aristotle proposed that associations develop from two events that are contiguous, physically similar, or polar opposites. 17 John Locke, a 17th century British philosopher, expanded on Aristotle’s ideas Claimed All that there are no innate ideas ideas result from experience Distinguished between simple ideas which are based on sensory input and complex ideas which are combinations of several simple ideas David Hume 18 Proposed three principles of association connect simple ideas into a complex one: Resemblance Contiguity Cause and Effect Thorndike 19 Edward Thorndike Unlike Locke and Hume, who were philosophers, Thorndike was a scientist Work with cats in the puzzle box led to Law of Effect Law of Effect stated that a response made in the presence of a stimulus that leads to a satisfying result will strengthen the bond between the stimulus and the response. 19 20 21 Law of Readiness stated that the organism must be motivated to develop an association or to exhibit a previously established habit. It is noteworthy that, in Thorndike’s formulation, the consequence or reward was merely a facilitator to strengthen the stimulus-response relation. Future behaviorists would hypothesize about the importance of the role of the motivation 21 22 Thorndike also proposed the concept of Associative shifting or the gradual changing of the stimulus could result in the association of that response to a totally new stimulus. Pavlov 23 Pavlov believed that rules of association determine which behavior occurs in the learning situation. Was trained as a physiologist studying digestion, using the dog as a model He noticed that the dogs started to secrete stomach juices before the food was placed into their mouths He concluded that the dogs had learned a new behavior 24 25 Unconditioned stimulus Unconditioned response An innate reaction to an unconditioned stimulus Conditioned stimulus An environmental event that can elicit an instinctive reaction without any experience A stimulus that becomes able to elicit a learned response as a result of being paired with an unconditioned stimulus Conditioned response A learned reaction to a conditioned stimulus 26 Generalization Responding in the same manner to similar stimuli Extinction The elimination or suppression of a response caused by the removal of the conditioned stimulus Watson 27 John B. Watson demonstrated the importance of Thorndike and Pavlov’s learning principles to human behavior. His belief that abnormal as well as normal behavior can be the result of learning led to the Little Albert Study. Little Albert Study 28 Subject: 9 month old boy (Albert) UCS or US: loud noise CS: White rat Initially, the boy was not afraid of the rat. Then, each time he reached out for the rat, Watson & Raynor sounded a loud gong behind his back, causing a fear response Eventually, Albert showed a fear response to the white rat alone Thus, Watson & Raynor demonstrated that phobia could be learned. 29 30 One of Watson’s students, Mary Cover Jones, demonstrated that phobia could be “unlearned”. Peter and the Rabbit 31 Subject: Three year old Peter Problem: Peter was afraid of rabbit Procedure: Mary Cover Jones first brought the rabbit into a room where Peter was at ease and eating. Eating produced a positive emotional state whereas the rabbit produced a negative emotional state. She kept a comfortable distance but gradually brought the rabbit closer and closer. Eventually Peter could touch the rabbit without fear. 32 The process was called counterconditioning. Counterconditioning: the elimination of a conditioned response when the conditioned stimulus is paired with an opponent or antagonistic unconditioned stimulus. This played an important role in the development of the behavior modification technique of systematic desensitization. Are all forms of learning associative? 33 Led to the Cognitive “Revolution” Adding Cognition into the Picture Thinking/Reasoning Explicit Habituation Implicit Conditioning Semantic Episodic Skills Classical Instrumental Multiple Forms of Learning Sloman’s Evidence 1) Dissociations “H.M.” “Unconscious Sequence Learning” 2) Simultaneous Contradictory Belief “Linda Problem” “Visual Illusions” H.M. Sequence learning Nissen & Bullemer (1987) – Serial Reaction Time A B C * D Experimental Group = fixed sequence of locations D–B–C–A–C–B–D–C–B–Acircular sequence, 10 times per block Control Group = random sequence of locations Violated Sequence Subjects are sensitive to the presence of the sequence even when they deny knowing that there was a sequence Linda Problem Linda is 20 years old, single, outspoken, and very bright. She majors in philosophy. As a student, she is deeply concerned with issues of discrimination and social justice, and participated in the Occupy Wall Street Movement. Which of the following is more probable? (1) Linda is a bankteller. (2) Linda is a bankteller and a member of the NDP. Müller-Lyer Illusion Why Study Animal Learning? 1) precise control 2) start simple 3) use potent stimuli 4) model behavioural dysfunctions 5) avoid subjective data 6) interest in its own right Learning 3 Types of Questions? 1) Can it be learned? 2) What conditions encourage/hinder learning? 3) What is the underlying mechanism? Learned: Delayed Responding? Rats: 10-s Racoon: 25-s Choice Cue Dog:Location 5-min 1 Human Location 22 Location 1-year: 24-s Location 3 2-year: 50-s 6-year: 20-min Hunter (1913) Conditions: Delay of Reinforcement Grice – (1948) Choice Delay Goal Start Reward or No Reward Grice (1948) Results 1.2 s 100 90 80 70 60 50 40 30 20 2s 5s Trials 700 625 550 475 400 325 250 175 100 10s 25 Percent Correct 0s 0.5s Mechanism: Insight or Trial and Error? Kohler (1914) Is Sultan reasoning through to the solution?