GENERAL PSYCHOLOGY II. Dr. Albina Colden

Transcription

1 GENERAL PSYCHOLOGY II Dr. Albina Colden

2 GENERAL PSYCHOLOGY II 1. A (re-)introduction to Psychology 2. Quantifiable Responses: Behaviourist Learning. sensitization. habituation. classical conditioning. operant conditioning 3. The Mental World: Cognition. schema theory. priming, framing, and subliminal processes. cognitive dissonance and the drive for coherence. self-awareness, intent, and free will: an illusion? 4. Memory. memory systems. memory processes

3 neurological & biological processes mental processes social processes developmental processes Motivation Attention Perception Emotion Cognition Learni n g Memory Behaviour Biological Psychology Behaviorism Cognitive Psychology Psychology of Emotion Memory Individual Difference s Social Psychology Neuropsychology Cross- Cultural Psychology Developmental Psychology Personality Abnormality

4 BEHAVIORIST LEARNING

5 BEHAVIORIST LEARNING Q What is Behaviorist Learning? How is it different from other types of learning?

6 BEHAVIORIST LEARNING Q What is Behaviorist Learning? How is it different from other types of learning? A Behaviorist Learning is focused on external behaviour focused on the prediction and control of behaviour quantitative and quantifiable physiological / neurological (not cognitive) automatic (happens regardless of intent) not limited to human beings; can take place in any life form

7 The Birth of the Term Behaviourism John B. Watson John Broadus Watson, a godfather of American behaviorist psychology, tests grasp reflex in a baby, circa (Courtesy Johns Hopkins University Archives/From "World as Laboratory )

8 The Birth of the Term Behaviourism John B. Watson published article: "Psychology as the Behaviorist Views It " (1913) (sometimes called "The Behaviorist Manifesto." ) In this article, Watson outlined the major features of his new philosophy of psychology, called "behaviorism." Watson s idea of behaviorism emphasised external behavior rather than the internal, mental state The analysis of behaviors and reactions = the only objective method to get insight in the human action.

9 The Birth of the Term Behaviourism John B. Watson "Psychology as the Behaviorist Views It " (1913) Psychology as the behaviorist views it is a purely objective experimental branch of natural science. Its theoretical goal is the prediction and control of behavior. Introspection forms no essential part of its methods, nor is the scientific value of its data dependent upon the readiness with which they lend themselves to interpretation in terms of consciousness. The behaviorist, in his efforts to get a unitary scheme of animal response, recognizes no dividing line between man and brute. The behavior of man, with all of its refinement and complexity, forms only a part of the behaviorist's total scheme of investigation.

10 The Birth of the Term Behaviourism John B. Watson Behaviourism (1930) 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, merchantchief and, yes, even beggar-man and thief, regardless of his talents, penchants, tendencies, abilities, vocations, and race of his ancestors. I am going beyond my facts and I admit it, but so have the advocates of the contrary and they have been doing it for many thousands of years.

11 BEHAVIORIST LEARNING I. Simple Learning (non-associative). Sensitisation. Habituation II. Associative Learning. Classical Conditioning. Operant Conditioning

12 BEHAVIORIST LEARNING Simple Learning: Sensitization repeated stimulation causes progressive amplification of a response Example: Rubbing your arm continuously will cause repeated stimulation of peripheral nerves this stimulation will first create a warm sensation, then will gradually become painful. pain is the result of progressively amplified synaptic response of the peripheral nerves biological function of this: to warn that the stimulation is harmful.

13 BEHAVIORIST LEARNING Simple Learning: Sensitization 3 types of Sensitization: long-term potentiation (gradual buildup) kindling (sudden crossing over a thresh-hold) central sensitization (peripheral nerve response spreads centrally to cause overall sensation)

14 BEHAVIORIST LEARNING Simple Learning: Sensitization Examples of Sensitization: Allergies Drug addiction Pain hypersensitivity Orgasm Seizure! long-term potentiation, kindling, or central sensitization?

15 BEHAVIORIST LEARNING Simple Learning: Habituation Progressive diminishing of behavioural response with repetition of a stimulus The orientating response makes us initially react to a stimulus. But, if it is neither rewarding nor harmful, then subsequent responses are reduced. Habituation has been shown in essentially every species of animal occurs through neural adaptation in sensory nerves themselves and through negative feedback from the brain to peripheral sensory organs

16 BEHAVIORIST LEARNING Simple Learning: Habituation Examples of Habituation Touch: feeling your clothing on your skin: the sensation eventually disappears Smell: walking into a smelly environment, and at first thinking it is unbearable then getting used to it and not even being able to smell it any longer. Taste: Something that initially tastes too sweet (or salty), but gradually begins to taste normal Sight: we gaze less and less at a particular visual stimulus the longer it is presented. Sound: being initially distracted by a noisy environment, but then getting used to it and no longer even really hearing the sound

17 BEHAVIORIST LEARNING Simple Learning: Habituation Habituation Curve

18 BEHAVIORIST LEARNING Simple Learning: Habituation Habituation Curve Habituation depends on:. time between presentations of stimulus. similarity of stimuli (identical versus similar or familiar)

19 BEHAVIOURIST LEARNING Associative Learning. Classical Conditioning

20 BEHAVIOURIST LEARNING Associative Learning. Classical Conditioning VIP s: Pavlov Watson

21 Classical Conditioning: Ivan Petrovich Pavlov

22 Classical Conditioning: Ivan Pavlov In the 1890s, Pavlov was investigating the salivary glands of dogs externalised the salivatory gland in order to collect and analyze salivatory response to food under different conditions. In performing these experiments, Pavlov noticed that the dogs tended to salivate before food was actually delivered to their mouths decided to investigate this "psychic secretion instead of his previously planned research changed the focus of his research, carrying out a long series of experiments in which he manipulated the stimuli occurring before the presentation of food.

23 Classical Conditioning: One of Ivan Pavlov s Experimental Dogs

24 Classical Conditioning: One of Ivan Pavlov s Experimental Dogs

25 Classical Conditioning: Ivan Pavlov established the basic laws for the establishment and extinction of what he called "conditional reflexes" - reflex responses, like salivation, that only occurred conditionally upon specific previous experiences of the animal. Experiments carried out int he 20s signaled the occurrence of food by ringing a bell. However, his writings record the use of a wide variety of stimuli, including electric shocks, whistles, tuning fork, and a range of visual stimuli, in addition to ringing a bell.

26 Classical Conditioning: Ivan Pavlov

27 Classical Conditioning: Ivan Pavlov Terminology NS: Neutral Stimulus US: Unconditioned Stimulus UR: Unconditioned Response CS: Conditioned Stimulus CR: Conditioned Response

28 Classical Conditioning:

29 Classical Conditioning in Humans: John B. Watson The Little Albert Study a well-known (infamous) experiment demonstrating classical conditioning in humans

30 Classical Conditioning in Humans: John B. Watson The Little Albert Study chose the baby Albert B. from a hospital for this study at the age of nine months Albert was the baby of an employee at John Hopkins University, where John B. Watson did his research

31 Classical Conditioning in Humans: John B. Watson The Little Albert Study Before the commencement of the experiment, Little Albert was given a battery of baseline emotional tests; the infant was exposed, briefly and for the first time, to a white rat, a rabbit, a dog, a monkey, masks with and without hair, cotton wool, burning newspapers, etc. During these baseline tests, Little Albert showed no fear toward any of the items.

32 Classical Conditioning in Humans: John B. Watson The Little Albert Study : ) experiment began by placing Albert on a mattress on a table in the middle of a room. white laboratory rat was placed near Albert and he was allowed to play with it. At this point, the child showed no fear of the rat. He reached out to the rat and made pleased noises as rat roamed near him.

33 Classical Conditioning in Humans: John B. Watson The Little Albert Study + BANG!! : ( In later trials, Watson and Rayner made a loud sound behind Albert's back by striking a suspended steel bar with a hammer when the baby touched the rat. During these trials, Little Albert cried and showed fear as he heard the noise.

34 Classical Conditioning in Humans: John B. Watson The Little Albert Study : ( After several such pairings of the two stimuli, Albert was again presented with only the rat. Now, however, he became very distressed as the rat appeared in the room. He cried, turned away from the rat, and tried to move away. Albert now associated the white rat with the loud noise and was producing a conditioned fear response

35 RAT (NS) --> --

36 NOISE (US) --> FEAR (UR) (natural response in infants)

37 RAT (CS) NOISE (US) --> FEAR (UR)

38 RAT (CS) --> FEAR (CR)

39 Classical Conditioning in Humans: John B. Watson The Little Albert Study : ( Side-effect: Little Albert seemed to generalise his response to other stimuli, not just the white rat: gray rabbit, furry dog, a fur coat, Santa Claus mask with white fluffy beard

40 Classical Conditioning in Humans: John B. Watson The Little Albert Study Watson and his colleagues had planned to extinguish these fearful reactions in Little Albert at the end of the experiment (pair the white rat with warm milk which babies love). However, Albert left the hospital on the day these last tests were made, and this did not took place Nothing is known of Albert's later life.

41 Classical Conditioning: Generalization When the CR occurs not only to the specific CS that was learned, but also to other stimuli with similar characteristics In the case of Little Albert, he became conditioned to respond with fear not only to the white rat, but also to fluffy things in general

42 Classical Conditioning: Extinction extinguishing of the conditioned response (CR), after repeated presentation of conditioned stimulus (CS) without the appearance of the unconditioned stimulus (US) The CR grows weaker and weaker when it is no longer paired with the US

43 Classical Conditioning: Extinction US --> UR CS US --> UR CS --> CR CS --> CR CS --> --

44 Classical Conditioning: Extinction CS --> CR CS --> CR CS --> CR CS --> CR CS --> CR CS -->

45 Classical Conditioning: Latent inhibition exposure to a stimulus alone prior to conditioning trials slows or prevents conditioned associations with that stimulus being formed.

46 Classical Conditioning: Latent inhibition NS NS NS NS (now becomes CS) US --> UR NS will have difficulty becoming a CS and evoking a CR CS -- > CR? (maybe, but more trials will be needed)

47 Classical Conditioning: Learned inhibition A conditioned stimulus-response relationship can overpower a naturally occuring (unconditioned ) stimulusresponse relationship

48 Classical Conditioning: Learned inhibition Example: mice and anxiety (Kandel & Pollak) mice conditioned to associate safety with a sound When they hear this sound, they experience less anxiety even in stressful situations that would normally evoke high anxiety

49 Classical Conditioning: Blocking Effect (Kamin, 1969) conditioning to a stimulus could be blocked if the stimulus were reinforced in compound with a previously conditioned stimulus.

50 Classical Conditioning: Blocking Effect (Kamin, 1969) US --> UR CS1 US --> UR CS2 CS1 US --> UR CS1 --> CR CS2 --> --

51 Classical Conditioning: Preparedness (Martin Seligman, 1970) associative learning is not an arbitrary process; the ease with which associations can be formed depends on biological predispositions shaped by the specialised evolutionary history of a species.

52 Classical Conditioning: Preparedness (Martin Seligman, 1970) an organism can be either:. prepared,. nonprepared, or. contraprepared for associative learning. Preparedness is a predisposition to learn an association rapidly; Nonpreparedness is the neutral middle of the preparedness continuum, where the associations to be learned are acquired neither rapidly nor slowly; Contrapreparedness is the opposite pole, where an animal learns an association only with great difficulty.

53 Classical Conditioning: Preparedness selectivity of association in species: certain birds locate food by its visual characteristics, rather than by its taste, like rats Wilcoxin et al (1970) Trained rats and quail Taste + Visual quality paired with poison --> illness

54 Classical Conditioning: Preparedness Wilcoxin et al (1970) Rats and Quail: Blue Sour Water (CS) Poison (US) --> Illness (UR) which aspect of the water was trained as the CS? the blue colour or the sour taste?

55 Classical Conditioning: Preparedness Wilcoxin et al (1970) Rats and Quail: Blue Sour Water (CS) Poison (US) --> Illness (UR) RATS: Sour Water (CS) --> Illness (CR) QUAIL: Blue Water (CS) --> Illness (CR)

56 Classical Conditioning: Preparedness (Martin Seligman, 1970) Seligman extended his preparedness thesis to human fears and phobias. Human fears appeared to be "(1) selective, (2)... resistant to extinction, (3) irrational, and (4) capable of being learned in one trial." (1971, p312) and non-cognitive. links this preparedness to evolutionary origins, pointing out that the great majority of phobias are about objects of ecological importance to the survival of the species (e.g. fear of darkness, fear of dangerous animals such as snakes and spiders).

57 Classical Conditioning: Preparedness (Martin Seligman, 1970) Oehman & Dimberg (1979; 1985) McNally (1987) used slides of snakes and spiders as conditioned stimuli and paired them with electric shock as the unconditioned stimulus. Conditioning to these stimuli was then compared with conditioning to stimuli such as slides of houses, flowers, and mushrooms.

58 BEHAVIOURIST LEARNING Associative Learning. Operant Conditioning

59 BEHAVIOURIST LEARNING Associative Learning. Operant Conditioning VIP s: Thorndike Skinner

60 Operant Conditioning: Edward L. Thorndike ( ) Operant conditioning, sometimes called instrumental conditioning or instrumental learning observed the behavior of cats trying to escape from homemade puzzle boxes. When first constrained in the boxes, the cats took a long time to escape. With experience, ineffective responses occurred less frequently and successful responses occurred more frequently, enabling the cats to escape in less time over successive trials.

61 Operant Conditioning: Edward L. Thorndike Cats In Puzzle Boxes Thorndike's Puzzle Box Procedure Thorndike placed a hungry cat inside a "puzzle box" with food outside. Initially, the cat would become agitated and produce many different "random" behaviours in an attempt to get out of the cage. Eventually, the cat would press the paddle by chance, the door would open and the cat could escape and get the food. The cat would then be placed inside the box again and would again take a long time (on average) to escape after exhibiting many different behaviours.

62 Operant Conditioning: Edward L. Thorndike Cats In Puzzle Boxes Thorndike's Puzzle Box Thorndike examined the time to escape (his operational definition of learning) as a function of trials. The learning curve was gradual and uneven (see below). There was little evidence of sudden insight. Nevertheless, after about thirty trials, the cats would press the paddle almost as soon as they were placed in the cage. Thorndike concluded that the animals learned by "trial and error".

63 Operant Conditioning: Edward L. Thorndike Law of Effect successful responses, those producing satisfying consequences, were "stamped in" by the experience and thus occurred more frequently. Unsuccessful responses, those producing annoying consequences, were stamped out and subsequently occurred less frequently. Result: some consequences strengthened behavior and some consequences weakened behavior.

64 Operant Conditioning: Edward L. Thorndike Law of Effect Learning Curve Thorndike produced the first known learning curves through this procedure.

65 Operant Conditioning: Edward L. Thorndike Law of Effect Learning Curve

66 Operant Conditioning: Edward L. Thorndike

67 Operant Conditioning: Factors that alter the effectiveness of consequences 1. Satiation: the appetite/desire for the result must be strong (cat needs to want to get out of the box!). 2. Immediacy: result must happen immediately after the desirable action in order for it to become cnditioned. 3. Contingency: the result must follow the action reliably and consistently 4. Size: The size, or amount/degree of the result must be significant enough to be worth the effort

68 Operant Conditioning: Burrhus Fredric Skinner ( ) B.F. Skinner formulated a more detailed analysis of operant conditioning based on reinforcement, punishment, and extinction. operant conditioning is: The learning process through which the consequence of an operant response affects the likelihood that the response will be produced again in the future. Unlike reflexes (in classical conditioning), operant responses are voluntary actions. In operant learning, the emphasis is on the consequences of a motor act rather than the act in and of itself.

69 Operant Conditioning: Burrhus Fredric Skinner ( ) Operant Chamber ( Skinner Box ) Skinner box is a cage with a lever or some other mechanism that the animal can operate to produce some effect, such as the delivery of a small amount of juice. allowed to measure rate of response as dependent variable using a cumulative record of lever presses or key pecks

70 Operant Conditioning: B. F. Skinner ( ) Three Consequences of Behaviour 1) Positive Reinforcement: stimulus that increases the probability of a behaviour (access to fish as positive reinforcer for a cat). 2) Negative Reinforcement: stimulus whose removal increases the probability of a behaviour. For example, bar pressing that turns off a shock. 3) Punishment: stimulus whose presence (as opposed to absence) decreases the probability of behaviour. For example, bar press that leads to a shock. Skinner thought that punishment was the least effective of the 3 possible consequences for learning.

71 Operant Conditioning: Avoidance learning Avoidance training is part of negative reinforcement. The subject learns that a certain response will result in prevention of an aversive stimulus. Example: Dog & Shuttle-box

72 Operant Conditioning: Learned Helplessness When the negative reinforcer (punishment) arrives regardless of action taken, the creature/individual soon stops trying, gives up When dog in shuttle-box experiment cannot predict shocks, it simply gives up and remains in the same place despite being continuously shocked. Once this effect occurs, it is very difficult to reverse, even if shock patterns become predictable again.

73 Operant Conditioning Examples in Humans Humans can be conditoned to perform behaviour by being reinforced for those behaviours: - positive reinforcers: smiling, food, gambling, affection - negative reinforcers: withholding of smiling, food, affection - punishments: frowning, crying, pain Experiment: The Operant Conditioning of Human Motor Behavior Verplank (1956) showed that even a socially/emotionally neutral stimulus that was described as a reward ( getting a point, which had absolutely no value outside the experiment) could shape human behaviour

74 Operant Conditioning Examples in Humans Experiment: The Operant Conditioning of Human Motor Behavior Verplank (1956)

75 Operant Conditioning Examples in Humans Experiment: The Operant Conditioning of Human Motor Behavior Verplank (1956). Participants were told that when the experimenter taps a pencil, this means they earn 1 point. There were no rules or explanations regarding what behaviour would cause this earning of points, only that the pencil tap would indicate it. After pre-determining the behaviour that he wanted to condition, the experimenter tapped his pencil whenever he saw the participant engage in this behaviour (for example, touching his face, or tapping his foot). With time, the participant began to unconciously engage in the desired behaviour more and more frequently. Participants did not report being aware of which of their actions caused them to earn points; they would perform the actions automatically and unconsciously

76 Behaviourist Conditioning in Humans? Is it possible? Is it effective? Is it ethical?

77 BEHAVIORIST LEARNING REVIEW Sensitisation long-term potentiation kindling central sensitization Habituation habitution curve Classical Conditioning NS / US / UR / CS / CR Pavlov (dogs) Watson (Little Alfred) generalisation extinction inhibition (latent & learned --> mice experiment) preparedness (rats/ quail blue sour water experiment)

78 BEHAVIORIST LEARNING REVIEW Operant Conditioning Thorndike (cat in puzzle box) Law of effect Learning curve Skinner (rats & pigeons) Positive reinforcement Negative reinforcement Avoidance learning Punishment Learned helplessness