the three categories of behaviours
- Reflexes are inevitable, involuntary responses to stimuli that are controlled by nervous system circuits located in the spinal cord and brainstem. They are beneficial by promoting welfare (e.g. pulling away when touching a hot stovetop), but have the disadvantage of being inflexible.
- Instincts (a.k.a. fixed action patterns) are inborn patterns of behaviour elicited by environmental stimuli. They share the reliability and lack of dependence on experience to reflexes, but are more complex; requiring much more neurons.
- Learning is a relatively permanent change in behaviour or the capacity for behaviour due to experience. Our behaviour changes as we mature.
Most human behaviour results from…
learning
he believed that human behaviour simply appears more complex and thoughtful because we often face the need to choose among competing instincts
William James (1887)
imprinting
when a young organism bonds with adults (e.g. baby swans follow their parents)
three categories of learning
- Associative learning is the formation of associations, or connections, among stimuli and behaviours; “If A happens, B is likely to follow.”
- Non-associative learning involves changes in the magnitude of responses to stimuli, rather than the formation of connections between them.
- Observational learning (a.k.a. social learning/modelling) occurs when one organism watches the actions of another organism, and provides the advantage of transmitting information across generations within families and cultures.
two types of associative learning
- Classical conditioning (a.k.a. Pavlovian conditioning) is when associations are formed between two stimuli that occur sequentially in time (e.g. if a child sees a bee and gets stung, the child forms a connection between seeing bees and the pain of bee stings; leading to them feeling frightened the next time they see a bee).
- Operant conditioning (a.k.a. instrumental conditioning) is when associations are formed between behaviours and their outcomes (e.g. if you park illegally and get a hefty ticket, you are likely to pay more attention the next time you park).
two types of non-associative learning
- Habituation is when reactions to repeated, unchanging, harmless stimuli decrease (e.g. someone who is not accustomed to young children may find it alarming to witness two kids who are screaming and rolling on the ground, whereas their mother (who is accustomed to the behaviour) wouldn’t bat an eye).
- Sensitization is the increased reaction to many stimuli following exposure to one strong stimulus (e.g. those who experience an earthquake experience exaggerated responses to movement, light, or noise).
Habituation ensures precious resources aren’t wasted when monitoring low-priority stimuli, whereas sensitization is useful in detecting high-priority stimuli.
implicit vs. explicit learning
Implicit learning occurs in the absence of conscious awareness, whereas explicit learning (what typically comes to mind when we think of “learning”) involves conscious awareness.
stimuli related to classical conditioning
Conditioned stimuli (CS) refer to environmental events whose significance is learned through classical conditioning, whereas unconditioned stimuli (UCS) elicit a response without prior experience, due to an innate biological significance.
In Pavlov’s experiment, dogs heard the sound of a ticking metronome (CS) before food (UCS) appeared.
responses related to classical conditioning
Conditioned responses (CRs) are learned through classical conditioning, whereas unconditioned responses (UCRs) require no previous experience.
acquisition
the development of a CR; it must be contiguous (closeness in time) and contigent (correlation between the CS and UCS)
CONTIGUITY:
- If the CS occured long before the UCS, the organism may not view the two as related.
- If the CS occured simultaneously or after the UCS, it would not be a useful signal.
CONTINGENCY:
- Learning about a reliable signal is easier than learning about a signal that occurs only sometimes.
extinction
the reduction of a learned response
- in classical conditioning, extinction occurs when the association between the CS and the UCS is broken
- in operant conditioning, extinction occurs when the consequence no longer follows the learned behaviour
spontaneous recovery
during extinction training, the reappearance of CRs after periods of rest; it takes time for the new learning to replace the old
inhibition
when a CS predicts the non-occurrence of an UCS
e.g. A predator at a watering hole in hunting mode is an excitatory CS eliciting fear, but a predator relaxing after a recent kill and calmly drinking water is an inhibitory CS that tells the animal that the predator is unlikely to attack soon.
stimuli generalizations
the tendency to respond to stimuli that are similar to an original CS
e.g. If our ancestors had one bad experience with a lion, it would make sense to avoid all lions, and animals with lion-like characteristics.
discrimination
a learned ability to distinguish between stimuli
e.g. If you present food following a high tone, but never a low tone, a dog will initially learn to salivate to both pitched tones, but as learning progresses, will eventually learn to differentiate between the abilities of the two stimuli to predict food.
higher-order conditioning
learning in which stimuli associated with a CS elicit CRs
e.g. A person who was bitten by a dog might show fear the next time the dog is seen (CS). The sight of the dog could subsequently act more like an UCR, and produce fear in response to other stimuli, like hearing the dog bark, that might signal the dog’s appearance.
latent inhibition
the slower learning that occurs when a CS is already familiar, compared to when the CS is unfamiliar
e.g. If you’ve eaten lots of pizzas over time and get sick after eating one, you’d probably not associate the pizza with sickness. However, if you got sick the first time you ate chocolate-covered ants, you’d associate the two.
the Rescorla-Wagner model
Early in training, learning proceeds more rapidly when the association (between the CS and UCS) is new and surprising. However, later in training, learning is slower as the association is now familiar and no longer surprising.
taste aversion
when the sight, smell, or flavour of a food (CS) has been paired in the past with illness (UCS), resulting in the dislike of said food (CR)
Garcia and Koelling’s rat experiment
Rats were given either sweetened water (“tasty water”), or normal water that triggered a light and clicking sound when drank (“bright-noisy water”). The rats were then either injected with lithium chloride to induce nausea, or were shocked. Rats that drank tasty water made quicker associations with the nausea, and rats that drank bright-noisy water made quicker associations with the shock.
This experiment had profound implications on classical conditioning, and behaviourism as a whole, as it challenged Pavlov’s views that stimuli could be easily interchangeable and prompted a renewed interest in the biological preparedness to learn things.
Albert’s white rat experiment, and its significance
In 1920, John B. Watson and Rosalie Raynor conducted an experiment with 9-month-old Albert. When Albert would play with a white lab rat (CS), Watson and Raynor made a loud noise (UCS) by hitting a steel bar with a hammer. Albert would then get frightened by the noise (UCR). A week later, when Albert was again offered the rat, he was afraid (CR); his fear generalized to other white, furry objects, like rabbits, dogs, and fur coats.
This experiment demonstrated that fears could potentially result from classical conditioning.
exposure therapy (flooding)
treating phobias by exposing people to fear-producing stimuli in a manner that is safe, until they no longer respond (i.e. extinction)
counter-conditioning, and Peter’s leporiphobia
the substitution of one CR for another opposite response
e.g. In a 1924 experiment, Mary Cover Jones treated Peter, a 3-year old with a phobia of rabbits, by associating food (the new UCS) with the presence of a rabbit (CS). Eventually, Peter was able to pet the rabbit while eating.
