Learning part 1 (Classical Conditioning) Flashcards
Wilhelm Wundt (1832-1920)
First psychology laboratory (1875) at the University of Leipzig, Germany
He used experimental introspection: trained to report inner processes
Aim: discover the basic elements of thought (structuralism): laws by which mental elements combine into complex mental experiences
The mind / consciousness was to be analysed into its elements, just as in the physical sciences
William James (1842-1910)
School of Functionalism
wrote “The Principles of Psychology” (1890)
focused on the purpose (function) of consciousness, rather than on the structure of consciousness. He described the stream of consciousness, as opposed to the elements of consciousness
was greatly influenced by the work of Charles Darwin: For him, psychology was a biological science
Sigmund Freud (1856-1939)
Wrote “The Interpretation of Dreams” (1900) and was the founder of the School of Psychoanalysis
Described the role of the “unconsciousness mind”; used hypnosis, free association and dream analysis as tools
Also performed psychoanalytic therapy based on his theory
Careful: Psychoanalysis is not experimental psychology – because it is not falsifiable!
John B. Watson (1878-1958)
School of Behaviourism
Turning away from “inner processes” to observable behaviour: the mind is a “black box” and only the relationship between stimuli and responses is important
Influenced by animal studies on associative learning and reflex responses
“Psychology as the Behaviourist sees it is a purely objective science. Its theoretical goal is the prediction and control of behaviour.… Psychology must discard all references to consciousness.”
Burrhus Frederic Skinner (1904-1990)
Peak of Behaviourism in the 50’s and 60’s
He regarded reinforcement and punishment as causes of voluntary behaviour; all behaviour is learned from environmental cues
Mental states exist but are not causal in determining behaviour; behaviour is the result of nurture not nature
He used behaviour modification techniques based on this work that are still applied in clinical/therapeutic settings
Edward C. Tolman (1886-1959)
One of the psychologists associated with the Cognitive Revolution
Demonstration of active learning: even rats have mental maps – we have to take into account the mental representations, not only stimuli and responses
He was interested in mental processes as the determinants (causes) of behaviour: nature (cognitive capacities) in addition to nurture
What is learning?
Learning is the process by which experience or practice results in a relatively permanent change in behaviour or in potential behaviour
Many learning studies used animal subjects: these allow for the precise control of the conditions under which a behaviour is learned
However, this assumes a level of similarity between species for generalisation of learning principles
Ivan Pavlov (1849-1936) (classical conditioning)
The first experiments were performed by Pavlov, a Russian physiologist who was originally interested in digestion in dogs
In order to get the dogs to produce saliva, Pavlov would put food on their tongues
After some days the dogs started to produce saliva automatically, before he put the food on their tongues
Dogs learned to associate the food with a signal (his footsteps) and salivated in anticipation (reflex behaviour)
Basic principles of classical conditioning 1
Classical conditioning always involves a reflex behavior
A reflex is a simple, unlearned response governed by the nervous system that occurs naturally in response to stimulus
Basic principles of classical conditioning 2
New stimulus-response relationship is learned by association
Pairing a neutral stimulus with a natural (unlearned stimulus) that automatically elicits a reflex response
Pavlov first rang a bell (initially neutral), then gave the dog food
The dog learned to salivate when bell sounded (conditioned response)
Unconditioned Stimulus (UCS)
A stimulus that always causes an organism to respond in a specific way (e.g., food)
Elicits a reflex response
Unconditioned Response (UCR)
A response that takes place in an organism whenever an unconditioned stimulus occurs (e.g., salivation to food)
Reflexive response
Conditioned Stimulus (CS)
An originally neutral stimulus that is paired with an unconditioned stimulus and eventually produces the formerly unconditioned response (e.g., the bell)
Conditioned Response (CR)
After conditioning, the CR is the response produced when the CS is present (e.g., salivation to bell)
Conditioning is strengthened by…
a) frequent pairings of the CS and the UCS
b) timing: CS is presented immediately prior to the UCS to make the CS predictive of the UCS
Extinction
gradually weakening conditioned responses – occurs when CS is repeatedly presented without the UCS
Spontaneous Recovery
The reappearance of a previously extinguished response
occurs when the dog was allowed a few hours rest, and after extinction the CS would again elicit the CR
Rapid Reacquisition
Once extinction occurred, re-learning is substantially faster when a second acquisition phase is introduced
This shows that extinction is not an unlearning of the conditioned response but a learned inhibition of responding. The initial learning is not lost, just inhibited
Limits of Classical Conditioning 1 (taste aversion)
learned taste aversion (John Garcia, 1950s): an organism’s innate behavior patterns can affect what is learned and how quickly it is learned
Classically conditioned dislike for / avoidance of a particular food develops when illness occurs after eating that food
However, it does not require repeated exposure - one bad experience is enough!
Additionally, the time span between CS (formerly benign food) and CR (vomiting) can be hours, not seconds
We seem to have a biological predisposition for learning this fast – however, this observation violates the basic assumption that everything can be conditioned in the same way
Limits of Classical Conditioning 2
‘Biological Preparedness’
Learned taste aversion in chemotherapy
Colour and taste (Wilcoxon et al. 1971)
Seligman proposed the principle of “Biological Preparedness”: no equivalence of associability – Organisms are biologically prepared to learn certain associations quickly because they ensure survival
Example 1: Learned taste aversion in chemotherapy:
Associations between nausea and food are acquired during treatment in chemotherapy, despite awareness that the food is not what is causing the nausea, but the treatment
Example 2: Colour and taste
Wilcoxon et al. (1971) presented quails and rats with blue-sour water followed by nausea (conditioning). Then they tested separately what the animals would avoid later:
Quails avoided the blue water, rats avoided the sour water
The reason is that quails select food on basis of vision, but rats select based on smell
Phobias
Another example for biological preparedness are phobias
Phobias are extreme, irrational fears of a specific objects, animals or situations
Particular stimuli are more likely to generate phobias because of their salience to survival (e.g. natural objects, situations)
Limitations of phobias being classically conditioned
Conditioning will not allow just any phobia to be acquired
It is easy to create a phobia of snakes by pairing an image of a snake with an electric shock, but hard to create a phobia for flowers
A snake phobia also harder to extinguish
Phobias for other (very dangerous but evolutionary novel)
objects can’t be acquired at all. e.g. power points
Classical Conditioning as an element in psychotherapy
Phobias can be unlearned via gradually pairing phobic stimulus with positive experience: exposure in Cognitive-Behavioural Therapy (CBT)
Desensitisation Therapy (Wolpe, 1973): relax in the presence of fearful stimuli (you can’t be both fearful and relaxed at the same time)
Using the conditioned response to drugs: A placebo response occurs as a physiological reaction to an inert (fake) drug because of the initial repeated pairing of “pill” with effect (therapeutic response)
Classical Conditioning as a mechanism in drug use
add this Marea
Modern views on Classical Conditioning
Conditioning reveals how organisms learn to mentally represent aspects of their world – we can learn something about cognitive models
Rescorla (1980): Effectiveness of CS determined by its predictive (informational) value
