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Learned Behaviour•Animals can learn to associate one stimulus with another, a process known as associative learning.
One of the types of associative learning is called classic conditioning.
experiment of Ivan Pavlov into classic conditioning
an alteration in the behaviour as a result of the association of external stimuli.
Ivan Pavlov
Russian physiologist who first described the phenomenon now known as conditioning in experiments with dogs. He was awarded the Nobel Prize in Physiology and Medicine in 1904.
(1849 - 1936)
Consider a hungry dog who sees a bowl of food. Something like this might happen:
Food ---> SalivationThe dog is hungry, the dog sees the food, the dog salivates. This is a natural sequence of events, an unconscious, uncontrolled, and unlearned relationship.
Now, because we are humans who have an insatiable curiosity, we experiment. When we present the food to the hungry dog (and before the dog salivates), we ring a bell. Thus,
Bell with
Food ---> Salivation
We repeat this action (food and bell given simultaneously) at several meals. Every time the
dog sees the food, the dog also hears the bell. Ding-dong
Now, because we are humans who like to play tricks on our pets, we do another experiment. We ring
the bell (Ding-dong), but we don't show any food. What does the dog
do? Bell ---> Salivate
The bell elicits the same response the sight of the food gets.
the dog has learned to associate the bell with the food and now the bell has the power to produce the same response as the food
Now, where do we get the term, "Conditioning" from all this? Let me draw up the diagrams with the official
terminology. Food ---------------------> Salivation
Unconditioned Stimulus ---> Unconditioned Response"Unconditioned" simply means that the stimulus and the response are naturally connected.
"Stimulus" simply means the thing that starts it while "response" means the thing that ends it. A stimulus elicits and a response is elicited.
Salivary duct was relocated, to the outside of its cheekso that drops of saliva could be more easily measured
CHOCOLATE SALIVATION!!!!!!
One of the types of associative learning is called operant conditioning, also named trial-and-error learning.
An animal learns to associate one of its own behaviours with a reward or punishment and then tends to repeat that behaviour.
The experiment of B.F. Skinner into operant conditioning
Frederic Skinner
His work was influenced by Pavlov’s experiments
One of his best known inventions is the Skinner box. It contains one or more levers which an animal can press, one or more stimulus lights and one or more places in which reinforcers like food can be delivered. In one of Skinners’ experiments a starved rat was introduced into the box. When the lever was pressed by the rat a small pellet of food was dropped onto a tray. The rat soon learned that when he pressed the lever he would receive some food. In this experiment the lever pressing behavior is reinforced by food.
If pressing the lever is reinforced (the rat gets food) when a light is on but not when it is off, responses (pressing the lever) continue to be made in the light but seldom, if at all, in the dark. The rat has formed discrimination between light and dark. When one turns on the light, a response occurs
1950 Seymour Skinner
Imprinting Is a type of learned behaviour with a significant innate component, acquired during a limited critical period.
The experiment of Konrad Lorenz into imprinting
Konrad Lorenz1903-1989
Austrian zoologist and ethologist
was awarded the Nobel Prize for Physiology and Medicine in 1973 (organization of individual and group behavior patterns )
he discovered imprinting, an especially rapid and relatively irreversible learning process that occurs early in the individual's life.
He divided a clutch of greylag goose eggs, leaving some with the mother and putting the rest into an incubator.
The young reared by the mother showed normal behaviour, following her about as goslings and eventually growing up to interact and mate with other geese.
The artificially raised geese spend the first hours with the researcher instead of with their mother. From that day on, they steadfastly followed Lorenz and showed no recognition of their own mother or other adults of their own species.
Insight learning
is the ability of an animal to perform a correct or appropriate behaviour on the first attempt
in a situation with which it has had no prior experience.
Memory is essential for learning
is the ability to store and retrieve information related to previous experiences.
It depends on storage of information, often regarded as the
build up of a neural net in which the synapses between a group of
neurons are either strengthened or weakened.
Neuroscientists are investigating the cellular changes involved in memory and learning.
Memory and learning is a rapidly expanding field of research.
Learned behaviour improves chances of survival since it adapts
an animal to its environment thus generally enlarging its reproductive
success.
Learned behaviour patterns enable an organism to cope better with selective
pressures and provide quick and favorable adaptation to its environmental conditions.