Learning and AdaptationChapter 7

• Biology, cognition & culture• Adapting to the environment• Classical Conditioning• Operant Conditioning• Learning and the brain• Modelling• Observational learning

Biology, cognition & culture

• Theorized that the brain is prewired to learn• Learning mechanisms help us respond to one

or more adaptation challenges• Habituation: is the decrease in response

strength to a repeated stimulus– Not the same as sensory habituation!– Habituation: simple form of learning– Sensory Habituation: decreased sensory response

to a continuously present stimulus.

Adapting to the environment

• What is learning?– Process by which experience produces a relatively

enduring change in beahviour or capabilities• Measure learning by actual changes in performance• Can increase the strength of a response to a

repeated stimulus through sensitization– Typically with strong or noxious stimuli– Why? Increases response to potentially dangerous

stimuli.

Classical conditioning

https://www.youtube.com/watch?v=0asusjaYpe4 • 4 important elements: UCS, UCR, CR, CS– Unconditioned Stimulus: elicits a reflective or innate

response without prior learning– Unconditioned Response: reflexive or innate response

elicited by the UCS– Conditioned Stimulus: through association with the

UCS comes to elicit a conditioned response similar to the UCR

– Conditioned Response: response elicited by a conditioned stimulus

Common Conditioning Procedures

1) Forward short delayo CS present when UCS is presentedo Optimal learning

2) Forward trace conditioningo CS appears then goes off, then start of UCSo Learning occurs if delay 2-3 sec or less

3) Simultaneous conditioningo CS and UCS presented at same timeo Slow learning

4) Backward conditioningo UCS presented before CSo Learning rarely occurs

Extinction

• Process in which CS is presented in absence of UCS

• Causes CR to weaken and eventually disappear• *KEY*: repeated presentation of CS without

UCS• Spontaneous recovery: after a rest period

without new learning the reappearance of a previously extinguished CR

Factors that enhance Acquisition

• Multiple CS-UCS pairings• Intense, aversive UCS can produce one-trial learning• Forward (short-delay) pairing• Time interval between onset of CS & onset of UCS is

short• Generalization: stimuli similar to initial CS elicits a

CR• Discrimination: CR occurs to one stimulus but not

to another

Higher Order Conditioning

• Chain of events which has 2 CS stimuli• Expands influence of classical conditioning on

behaviour• Ex. Dog already CR to a bell which CS is

salivation. – Pair the bell with a black square which will eventually

become a new CR and elicit the CS• Conditioning a fear response– Little albert

Applications to Daily Life

• Acquisition of Fetishes– Fetishism - experiencing sexual attraction to nonliving

things– Suggested that pairing neutral objects with sex can lead to

fetishes• Acquisition- overcoming fear– Exposure therapy

• Extinction of CR through exposure to CS without presence of UCS allowing extinction to occur

• Systematic desenitization• Flooding

CTA vs. CTP

• CTA= Conditioned taste aversion– Ex. Alcohol– Can occur in clinical application• Chemotherapy and radiation• 50% of patients develop (ANV)

• CTP= Conditioned taste preferences– Ex. buckleys

Operant conditioning

https://www.youtube.com/watch?v=Mt4N9GSBoMI • Facilitates personal adaptation• Reinforcement– Response strengthened by outcomes that followed

• Punishment– Response weakened by outcomes that follows

Law of Effect

• Thorndike’s Law of Effect– Response followed by a satisfying consequence

becomes more likely to occur– Response followed by an unsatisfying

consequence becomes less likely to occur • Based on concept of instrumental learning– Behaviour is instrumental in bringing about certain

outcomes

Determining how to respond

• 2 types of reinforcements- strengthen responses– Positive and negative

• 2 types of punishments- weaken responses– Positive and negative

Consequences

• Positive reinforcement– Response is strengthened by presentation of a

stimulus that follows it• 2 types:1. Primary reinforcers: stimuli that are reinforcing

because they satisfy biological needs 2. Secondary reinforcers: acquire reinforcing

properties through association with primary reinforcers

Consequences

• Positive Punishment– Response weakened by subsequent stimulus

presentation– Produces rapid results

• Negative reinforcement– Response strengthened by removal (or avoidance)

of an aversive stimulus (negative reinforcer)• Negative Punishment– Response weakened by removal of stimulus

Types of Reinforcement

• Positive– When a pleasant consequence follows a response,

making the response more likely to occur again– Ex. Behaviour = studying; PR = good grade

• Negative– When a response is followed by the removal of

something unpleasant, making the response more likely to occur again

– Ex. Behaviour = studying; NR= nagging stops• **something is being applied or given

Types of Punishers

• Positive– When something unpleasant occurs after a behaviour– Ex. Behaviour = studying; PP = ridicule by friends

• Negative– When something pleasant is removed after a

beahviour– Ex. Behaviour = studying; NP = loose time with friends

• **something is being taken away

Immediate vs Delayed consequences

• Immediate– Stronger effect on behaviour

• Delay of Gratification– Involves ability to forego immediate reward for

more satisfying outcome later– Kids show less D of G.

Shaping & Chaining

• Shaping– Reinforce successive approximations toward a

final response• Chaining– Reinforce each response with opportunity to

perform the next response– Develops a sequence of behaviours

Conseqeunces• Operant extinction– Weakening and eventual disappearance of an operant

response– Resistance to extinction influences by pattern of

reinforcement that has maintained behaviour• Generalization– Operant response occurs to a new antecedent stimulus or

situation similar to the original one• Operant discrimination– Operant response occurs to once antecedent stimulus but not

another• Stimulus control– A discriminative stimulus influences a behaviour

Schedules of Reinforcement

• Continuous reinforcement– Every response of a particular type is reinforced– Extinguishes very quickly

• Partial reinforcement– Only some responses are reinforced– 2 dimensions• Ratio vs interval• Fixed vs variable

Partial Reinforcement• Fixed interval schedule (FI)– First correct response after a fixed time interval is reinforced. Ex.

Every 3 mins • Fixed ratio schedule (FR)– Reinforcement given after a fixed number of responses. Ex. Every

3rd response• Variable interval (VI)– Reinforcement given for first correct response after a variable time

interval, centered around an average. Ex. On average 3 mins interval

• Variable ratio schedule (VR)– Reinforcement given after a variable number of responses,

centered around an average ex. 3 responses need for reinforcement

Escape and Avoidance

• Escape conditioning– Learn responses to terminate aversive stimuli– Ex. Taking an Advil to relive a headache

• Avoiding conditioning– Learn responses to avoid aversive stimuli– Ex. In winter dress warmly before going out into

the cold

Learning & Extinction

• Continuous reinforcement– More rapid learning– Consequences easier to perceive– Extinction more rapid

• Partial reinforcement– Slower learning– More resistant to extinction- especially on variable

schedule- due to unpredictability

Avoidance Learning• Shuttle box– Chock administers and rats run to the other side of the box– Negatively reinforced: escape removed shock– Introduce warning light– Conditions the light to be associated with shock which leads

to avoidance learning– Hard to extinguish

• Two-factor theory of avoidance– Classical conditioning

• Light paired with shock (UCS), light becomes CS that elicits fear CR– Operant conditioning

• Fleeing from light is negatively reinforced by termination of fear• strengthens & maintains avoidance response

Constraints on Operant Conditioning

• Instinctive drift– Conditioned response ‘drifts back’ toward

instinctive behaviour– Ex. Training a pigeon to peck for food is easy

because they biologically are primed to peck for food• Hard to train a pigeon to peck to escape a shock

because they would fly away to escape something dangerous or unpleasant

Classical vs. Operant Conditioning

• Classical– Behaviour changes due to association of two stimuli (CS-

UCS) presented prior to the response (CR)– Focus on elicited behaviours- CR triggered involuntarily

• Operant– Behaviour changes as a result of consequences that follow it– Focuses on emitting behaviours- that are under physical

control• *Although both are different processes- many learning

situations involve both

Learning and the Brain

• No single part controls learning• Nucleus accumbens & dopamine– Involved in ability to experience reward

• Cerebellum– Plays a role in acquiring some classical conditioned

behaviour. Ex. Eye blink response• Amygdala – Involved in acquiring classically conditioned fears

Modelling

• Bandura• Bobo doll experiment• Kids would watch a model behave aggressively

towards the doll– Some models were rewarded & some

reprimanded & some no consequences– Those who saw models punished had fewer

aggressive acts- but when given the incentive could still perform them

Observational Learning

• 4 basic steps1. Attention2. Retention3. Reproduction4. Motivation (the key component)

Review Questions1. Pavlov determined that a tone triggered salivation more quickly when the size of the was more intense or greater. A. unconditioned response B. unconditioned stimulus C. conditioned response D. conditioned stimulus

2. Under which of the following conditioned stimulus-unconditioned stimulus pairing conditions does learning usually occur most quickly? A. forward trace pairing B. forward short-delay pairing C. simultaneous pairing D. backward pairing

3. A man becomes moderately aroused whenever his wife wears a particular red outfit. In terms of classical conditioning principles, the red outfit represents a(n) that has become a(n) . A. conditioned stimulus; unconditioned stimulus B. previously neutral stimulus; conditioned stimulus C. unconditioned stimulus; conditioned stimulus D. unconditioned response; conditioned response

4. A young child is hungry and wants a cookie but is too short to reach the table where the cookie jar is kept. She tries various things to get the jar, such as jumping or throwing her teddy bear at the jar in hopes of knocking it off the table, but to no avail. Eventually, almost by accident, she realizes that she can pull the tablecloth on which the jar sits and is thus able to reach the jar. In the future, she will be more likely to try this technique again since it was effective. This example best demonstrates: A. Thorndike's law of effect. B. the principles of classical conditioning. C. the concept of shaping. D. the use of partial reinforcement.

5.Giving athletes random drug tests and police officers setting up roadside speed traps are examples of the: A. fixed interval schedule. B. fixed ratio schedule. C. variable interval schedule. D. variable ratio schedule.

For Shugar’s Class in Particular

Figures & tables you should really know • Figures: 7.3, 7.4, 7.5, 7.6,

7.12, 7.15, 7.20, 7.27, 7.29• Table 7.1• What to do with them? explain them to a friend

it really helps!• For extra help go to this youtube channel (abudl

Rahman- psychology 101) for videos on classical and operant conditioning and other psychological concepts