1
Q
____________________ learning is vital to the survival of a species.
A
unconscious reflexive
2
Q
Learning is
A
Mechanisms of behaviour that undergo relatively enduring (continuing or long-lasting) change based on experience.
- We can subdivide this definition of learning into 3 concepts:
(i) mechanisms of behaviour
(ii) an enduring change
(iii) being based on experience
3
Q
SLIDES: Associative learning is
A
learning how 2 or more pieces of info r related
4
Q
the brain changes during learning
A
- Long-term potentiation (LTP): the strengthening of synaptic connections between neurons
5
Q
SLIDES: Behaviourism:
A
- we learn from experience
- Pavlov: reflexive responses associate with cues
- Watson: interaction of environment & associated effects
- skinner: prediction & control of behaviour
- psychological orientation focused on measurement of observable behaviour rather than internal processes
6
Q
I. MECHANICS OF BEHAVIOUR
A
- why do we focus on mechanisms of behaviour instead of simply “changes in behaviour”
–>cuz performance ‘snapshot’ doesn’t always capture how much learning has taken place, we need to define learning in terms of the mechanisms underlying a behaviour rather than behaviour itself - During learning process, we rely on performance as an indirect index of how much learning has taken place.
–> but there r many ex where learning has occurred even though there are minimal changes in performance= latent learning
-On the other hand, some variables drastically affect performance without reflecting a change in learning
–> Ex, you just trained your dog to sit by rewarding her with treats. One day you try to get your dog to sit in front of friends, but your dog naps instead. –> Rather than signify a lack of learning, this failure to perform may have been caused by your dog being too tired, or not hungry enough for the treat. –> Later when your dog is less tired or more hungry, she may once again perform the trick, suggesting the learning was intact all along
7
Q
Latent Learning Experiment
A
- type of experiment was 1st conducted by H. C. Blodgett in the 1920s, & famously replicated by E.C. Tolman in his landmark paper Cognitive Maps in Rats & Men in 1949
- Rats were set loose in a complex maze –> 3 rat groups were given access to the maze under diff conditions
–> 1st group: exposed to the maze each day with food in the goal box; quickly learned the correct route, & after several days would run directly to the goal box, making few wrong turns
–> 2nd group: exposed to the maze each day but with no food in the goal box; tended to meander, & though a rat might wander into the foodless goal box, there was no increase in this behaviour across day
–> 3rd group: treated like 2nd group (with no food in the goal box) for first 10 days & displayed the same meandering behaviour. On Day 11, however, food was first introduced to the goal box. –> When these rats were placed back into the maze on Day 12, they performed similarly to rats from the 1st group, quickly running to the goal box with few errors.
–> Thus, it seems the 3rd group had been learning the maze’s layout in the absence of rewards, forming what Tolman would call a ‘cognitive map’ of the maze. –> Only once food was present did performance begin to reflect the learning that had taken place.
8
Q
II. Enduring Change
A
- Changes to mechanisms of behaviour must be relatively enduring (long-lasting) to be considered learning. –> don’t have to be permanent, but to be considered learning, they should be retained over time even if the behaviour is not performed in that time.
-Ex, changes to behaviour caused by fatigue will presumably go away after some rest. –> contrast: once u have learned to ride a bicycle, u can likely get back on after months or years of not riding & still perform at a similar level
9
Q
III. Based on Experience
A
- To be considered learning, changes to the mechanisms underlying a behaviour must also be based on experience
- We can contrast learning with other changes in behaviour driven by maturation –> Ex, it would be strange to say the tadpole learned to hop. Instead, the tadpole matured into a frog and gained legs, thereby allowing it to hop.
- In humans, maturation & learning r usually closely coupled to alter mechanisms of behaviour –> Ex, language ability
–> Maturation is necessary for a child to develop the motor control required to produce speech.
–> But, before this time, the child has already acquired considerable knowledge of words and their meanings
–>As a child matures and the vocal apparatus becomes more functional, speech production & language ability develop in tandem
10
Q
Non-human learning
A
- In classical conditioning we assume that learning works similarly in humans and non-humans. –>,scientists often study learning using non-human animal models cuz they afford greater experimental control, & so much of what we infer about human learning stems from research on non-human animals.
11
Q
Orienting Response is
A
an automatic shift of attention towards a stimulus
- You are programmed to notice novelty. –> When you become aware of a new stimulus or a change in the environment, it often leads to a reflexive orienting response
- It is worth pointing out that the stimulus must be something the organism is capable of perceiving. –> ex, flashing an infrared light would probably not produce an orienting response in a human subject cuz we r physiologically incapable of perceiving it.
12
Q
Habituation is
A
a decrease in response to a stimulus when it is repeatedly presented without consequences, thus reserving attention for more important stimuli.
- Orienting responses r important for focusing attention on unfamiliar stimuli, which may in turn signal sudden danger or an unexpected opportunity. –> but if ur attention were attracted to every perceptible change in the environment, u would quickly become overwhelmed
13
Q
Habituation examples: tactile simulation & scarecrows
A
Tactile Simulation
- When u 1st put on a hat, wristwatch, or ring, u r probably consciously aware of the new tactile sensation on that area of your body
- As time passes, however, u will stop being aware of it
- Note that this doesn’t mean u have become incapable of perceiving the stimulus. –>the constant stimulation, unaccompanied by other consequences, suggests to ur nervous system that the stimulus can be safely ignored.
Scarecrows
- birds may initially be startled by a scarecrow in a farmer’s field. –> This makes sense cuz failing to notice a potential predator can be fatal.
- But as the birds become familiar with the new object, which eventually proves to be harmless, habituation will occur—it will no longer scare the birds
- In this way, the farmer might be wise to regularly change the appearance or location of the scarecrow.
14
Q
Dishabituation is
A
An increase in responding that follows a change in a previously habituated stimulus.
- refers to when an organism habituates to a stimulus but then the stimulus changes, eliciting an orienting response or the recovery of responsiveness
–> Ex, you r in a forest for many hours and habituate to the sound of birds chirping. If these forest sounds suddenly stopped all at once, u would likely notice the change immediately, then attend to the chirping sounds if they began again. –> important cuz the change in familiar stimulus can signify important new info –> perhaps the birds have stopped chirping cuz they detected a nearby predator
15
Q
Sensitization is
A
An increase in response to a stimulus as it is repeatedly presented. Often adaptive, because is prompts you to engage in behaviours appropriate to escaping a potentially harmful stimulus
- focuses attention to stimuli that do have relevance
- You can observe a sensitized response when watching a suspenseful movie with friends –> As the repetitive music sets in and tension builds, emotions & anxiety become heightened
- The process of sensitization is also thought to play a role in many psychological processes, including drug dependence, asthma, depression & anxiety disorders, allergies, & epilepsy.
16
Q
Non-Associative Learning
A
- Habituation (& dishabituation too) & sensitization r considered simple forms of non-associative learning because they modify an existing stimulus-response relation, rather than create a new association between stimuli or between a stimulus & a response.
–> Ex, habituating to the tactile sensation of clothing on ur skin, the relation between the stimulus (physical force on your skin) & the magnitude of the response (perceived tactile sensation) changes, but the type of response is one that typically occurs in response to the stimulus–> no new stimulus or response is being associated with the og stimulus.
17
Q
Associative learning
A
- Associative learning, in animal behaviour, any learning process in which a new response becomes associated with a particular stimulus. (BRITANNICA)
- We will look @ 2 basic perspectives on associative learning:
–> Classical Conditioning: which focuses on associations between stimuli
–> Instrumental Conditioning: which focuses on associations between actions & their consequences.
18
Q
Classical conditioning
A
- associating 2 related events
-occurs when the CS elicits the CR without the US being present. - Classical conditioning is central to our lives and has been observed in many other species.
- aka Pavlovian conditioning –> work done by Russian Physiologist Ivan Pavlov in 1890s & 1900s
- can be both unconscious reflexive learning or conscious
19
Q
Intrumental Conditioning
A
- associating actions & consequences
20
Q
Pavlov’s Famous experiment
A
- dogs salivated before food in mouth
- sound of metronome was used to indicate that food was coming –> soon had no effect on dog before
- following training, dog salivated to the sound of the metronome alone –> conditioned reflex/response
- Note Pavlov had previously studied the reflexive regulation of the digestive glands (with dogs) by placing a small portion of dried meat powder in the dog’s mouth, then measuring how much salivation occurred. –> Salivation was measured by surgically diverting the dog’s salivary glands so that it emptied into a small tube
–> this earlier work set the foundation for his classical conditioning experiment as he noticed some dogs would start salivating as soon as the assistant entered the room –> he initially called it psychic secretion
21
Q
Pavlov was studying a ________________ ____________. Explain
A
contingent relationship
- the presentation of one stimulus leads to the presentation of another
–> when an organism learns the association between a signal & an event, we say that a continent relationship has formed between the 2 stimuli
22
Q
A contingency is
A
A term used to describe the association between the CS & US, cuz the presence of the CS reliably predicts the presence of the US
23
Q
Why r contingent relationships important for classical conditioning?
A
- they are the essence of classical conditioning
- when a contingent relationship is learned, an organism can respond to the signal before the event even occurs
- this conditional responses is preparatory in nature & can promote survival –> ex, salivating before u eat a lemon helps neutralize the acid & prep body for digestion
24
Q
Unconditioned Stimulus (US)
A
- any stimulus or event that triggers a response naturally in the absence of learning
- Ex, food in mouth of dog will naturally trigger a response without any training being necessary
25
Unconditioned Response (UR)
- The response that occurs after the unconditioned stimulus.
- occurs naturally prior to learning --> often biologically programmed reflex
26
A conditioned Stimulus (CS)
- previously neutral stimulus paired with the unconditioned stimuli to produce a learned contingency
- the conditioned stimulus typically appears before the unconditioned
- eventually triggers a response on it's own --> when this occurs, the organism has learned a contingent relationship between the 2 stimuli
--> Ex, the metronome
27
Conditioned response
- the response that occurs once the contingency relationship between the CS & US has been learned
- often very similar to US
--> Ex, sound of metronome will eventually come to elicit a conditioned response of salivation, just like the US (food)
28
Acquisition is
the process by which a contingency between a CS & US is learned
- Before conditioning begins, the CS may elicit an orienting response & some behavioural changes, but the CS does not elicit the CR.
- normally, contingencies r learned early, taking many trials before US & CS r effectively paired
- Pavlov characterized the process of acquisition as a negatively accelerating curve --> think of parent square-root function --> learning reaching an asymptote = refers to asymptotic responding?
--> makes sense as most learning would happen in the beginning = MAIN TAKEAWAY --> u quickly learn that lemon is sour or a glowing stove is hot
29
Asymptotic Responding
The CR will increase in strength over successive conditioning trials, but it will eventually asymptote when
1) We may have reached the subject's max physical ability to respond to the stimuli
OR
2) It's possible that we have reached the maximum conditioning possible with the specific stimulus pair
30
Pavlov also concluded that acquisition of the CR was dependent on _______________________. Explain
stimulus contiguity
- contiguity= The extent to which the CS & US occur together in time & space.
- All that was required for the sound of a metronome to become associated with presentation of food was that the 2 events occur closely in time & place.
- implies that any stimulus that produces an orienting response can be used as a CS & paired with any stimulus that produces a reflexive UR
- The optimal arrangement = short-delay conditioning cuz the CS is presented shortly before the US, often by only a few seconds.
--> the rate of acquisition declines sharply if CS & US r presented simultaneously or if the CS–US interval is too brief
--> conditioning also tends to become less effective when the CS–US interval is too great.
31
Conditioning Trials
- aka training trials
-Trials in which the CS and US are presented together. These trials create an association between the 2 stimuli.
32
Test Trial
- A trial where the CS is presented without the US. - Used to test whether a CS–US association has been learned.
- Not to be confused with extinction trials, where the CS is REPEATEDLY presented alone.
33
Acquisition usually takes many trials but in some cases, it only takes one. Give an example
RATS
- have developed special learning mechanisms for food selection to help them survive
- r constantly searching for food & run risk of poison --> thus, they generally avoid unfamiliar foods --> trait called Neophobia
- only eat small quantities of new food at a time, so if they get sick, they can effectively pinpoint the cause & never eat that food again
- US: poison, CS: taste of food, UR/CR: sickness --> results in taste aversion
- thus, they can learn the contingency between food & sickness in 1 trial.
34
Questions to ask to see if something is a US, CS, UR, or CR?
1) Is prior learning required for the stimulus to elicit a response?
- If no, unconditional
- if yes, conditional
2) Are you labelling the triggering event or its outcome?
- if triggering event, stimulus
- if outcome, response
35
How long do the effects of a learning trial (classical conditioning?) last?
- in theory, as long as the CS continues to be a reliable que for the US, the contingency will be maintained
- if it's not longer reliable, the CR will eventually fade
36
Extinction is
the loss of the CR when the CS no longer predicts the US
- it's the process of making the CR fade
- involves showing the CS alone repeatedly over many trials without the US it was paired with --> at first it will still elicit the CR, but over trials, CR will get weaker
37
Extinction trials
- The CS is repeatedly presented alone to extinguish the CS–US association.
--> Not to be confused with tests trials, where the CS is presented alone to test whether an association has been learned.
38
Is the process of extinction a process of unlearning or is it learning a new inhibitory response?
- New Inhibitory Response: response that counteracts or competes with the og contingency
39
Proof that extinction is not unlearning the CS but learning a new inhibitory response?
-unlearning hypothesis : retraining between CS & US again would lead to acquisition of CR at the same time rate as the og training
- new inhibitory response hypothesis: we r assuming that og learned response stays, but is modified by a new inhibitory learned response gained via extinction. --> thus, retraining between CR & UR again would lead to acquisition of CR at faster rate then the og training --> cuz there's already a foundation to build on
- THIS IS WHAT WE FIND
-Reacquisition, spontaneous recovery, & renewal suggest that parts of the CS–US association r retained after the CR has been extinguished, & therefore extinction is not simply the erasure of acquired association
40
Reacquisition
The reintroduction of conditioning trials after extinction has occurred.
-->Reacquisition is faster than acquisition, indicating that some of the original learning is retained following extinction.
41
Spontaneous Recovery is
the sudden recovery of a conditional response following a rest period after extinction
- the recovery is not to the full og strength (according to the graph)
- proof that the og learned association between CS & US is not unlearned --> rather a learned inhibitory response competes with the og learned contingency
- if unlearning, CR would be very low after the CS is presented after rest period
42
Renewal
phenomenon suggesting extinction is not the erasure of an acquired association.
- If an association is extinguished in an environment diff than the og environment of acquisition, a CR is sometimes still observed when the subject is placed back in the og environment.
- Renewal has applications for treating phobias cuz therapy usually takes place in a diff environment (e.g., the therapist’s treatment room) than where the patient is normally exposed to the CS.
43
Excitatory Conditioning
- When the presence of the CS predicts the presence of the US
- extinction is when a new inhibitory association begins to compete with the og excitatory association
44
What's going on during extinction trials to cause the CR to diminish in response to the CS
- 1 explanation is Inhibitory conditioning= presence of CS predicts absence of US
- The complexity of extinction suggests it may he driven by INHIBITORY LEARNING in that the subject learns a contingency with a stimulus & the absence of another stimulus.
- it's often just as useful for a CS to signal the absence of a biologically important event --> also advantageous to use cues to anticipate the absence of food, mates, or predators
--> Ex, if the metronome predicted the absence of food, salivation will acc start to decrease from baseline at the sound
45
When did Ivan Pavlov win the Nobel Prize?
- won Nobel Prize in Medicine in 1904
46
When did Eric Kendel win the Nobel Prize?
- won Nobel Prize in Medicine in 2000
- Understanding the learning mechanisms gives us insight into neural basis for learning, which was the principal research topic that led to his Nobel Prize
47
Stimulus Generalization is
the process by which stimuli similar to the CS will also elicit a CR --> the more similar the new stimulus is to the og stimulus, the greater the response
--> the strength of the CR follows a generalization gradient
- Ex, During the wartime bombing in WWII, people developed a conditional fear to the whistling sound of falling bombs --> this was the case even though the sound varied between bombs depending on distance, type, & weather conditions
- Ex, child bitten by Doberman will become fearful at the sight of other dogs other than Dobermans too
48
Stimulus Generalization & Hertz Experiment
- In a controlled fear conditioning experiment, a 500 Hz tone is paired with mild electric shock --> as training proceeds, presentation of 500Hz tone leads to conditioned fear response in humans--> measured through galvanic skin response
--> in animals, measured through freezing behaviour
- Testing for stimuli generalization by presenting various tones & measuring strength of response shows normal distribution= a generalization gradient
--> the highest response was the 500Hz and strength decreased as tone moved further away from from either side
- this generalization gradient can be applied to any dimension of conditioned stimulus --> ex, the fear of Dobermans & other dogs thing
49
Why is Stimulus Generalization important?
- it adds flexibility & efficiency to classical conditioning
- if stimulus is harmful, separate conditioning experiences will not be required to learn the important relationship. --> u will generalize & avoid similar dangerous stimuli
50
Extinction & Stimuli Generalization
- Undergoing process of extinction will flatten the gradient over time.
51
Stimulus Discrimination
- complement to stimulus generalization
- it's an organism's ability to fine-tune its responding such that a CR occurs in response to one CS, but not to other similar stimuli. --> Typically occurs through discrimination training.
--> while stimulus generalization allows a variety of stimuli to elicit a response to a degree, stimulus discrimination does the opposite
--> it restricts range of conditioned stimuli that can elicit a response
52
Stimulus Discrimination & previous Hertz Experiment example
- Stimulus discrimination can be shown more precisely in a controlled experiment using discrimination training.
- normally, fear CR generalizes to variety of tones on generalization gradient
- via stimulus discrimination, we can eliminate fear of 600Hz by repeatedly presenting it without shock
- the fear of 600Hz will diminish but the CR elicited by the rest of the stimuli along the gradient will remain intact
53
To test ability of participant to discriminate between 2 stimuli, researchers devised a rather unique experiment. Elaborate
- experiment tested 2 important variables: conditional stimulus plus (CS+) & condition stimulus minus(CS-)
- same as other 500hz & 600hz experiment
- experiment involved alternating trials, where 500hz=shock & 600hz= no shock
--> researchers achieved very precise disrcimination between the 2 types of CS --> fear will be pinpointed exactly to the 500hz.
- the CS- is thus said to evoke an inhibitory association with the US whereas the CS+ is said to evoke an excitatory association.
54
Learning to predict absence of biological stimulus is just as important as learning to predict its presence. Elaborate
- An antelope must learn to respond to a range of CS+ that predicts the PRESENCE of a predator
- It's also important for an antelope to learn about rand of CS- that predicts ABSENCE of predator --> indicating a safe space where the antelope can forage for food, etc
55
What happens when a CS+ & CS- r presented at the same time
- going back to Hertz experiment, if CS+ (500hz) & CS- (600hz) r presented together, participant will show fear response somewhere BETWEEN the responses elicited by the 2 cues
56
Stimulus generalization & discrimination r opposite sides of same coin. Explain
- Generalization provides efficiency & flexibility
- Discrimination refines learning process
--> together, allow an organism to build complex responses that allow adaptive interactions to the environment
57
Higher-order Conditioning
- A neutral stimulus is paired with a CS to produce the same CR as the CS
- allows a the new stimulus to become yet another CS capable of eliciting a CR.
- Ex, a tone (CS1) is paired with food (US), leading to salivation (CR). --> After robust conditioning has been established, the tone (CS1) is now paired with a light (CS2), but without food. After some CS1–CS2 pairings, the light alone may also elicit the CR.
- the CR elicited in higher-order conditioning is typically weaker and more vulnerable to extinction compared to the original CR
--> despite this limitation, higher order conditioning greatly expands the power & reach of associative learning --> Ex, as a child, Jane had a fear of being injected with a needle @ the doc’s office.--> the sight of a needle (CS) caused Jane to experience fear. --> In time, many associated stimuli—the doctor’s office, the familiar route there, even the word ‘doctor’—also came to elicit a fear response.
58
A phobia is
an exaggerated, intense, & persistent fear of certain situations, activities, things, or people
- it's what happens when conditional fears become too much to handle
- common phobias: ophidiophobia (fear of snakes), aviophobia (fear of flying on plane)
59
Classical conditioning framework useful for understanding formation of phobia
- ex, traumatic experience with snake (US) produces a long-lasting fear (UR/CR) elicited by stimuli that reminds them of the experience (CS)
- some cases, person does not need to direct experience a stimulus to elicit a response --> ex, being told a disturbing snake story (CS) may be enough to elicit response next time person thinks about trekking through a forest (CR)
60
Methods used to treat phobias
- 2 commonly used methods
1) Implosive therapy - individual with phobia is encouraged to confront the CS that invokes their anxiety using their imagination. --> CS is presented in absence of US
- can be traumatic experience to do
2) Systemic Desensitization
- more gradual approach
- think of generalization gradient --> they will start by extinguishing far end of curve, gradually working towards the middle
- this method may be more accessible to most patients
61
Homeostasis & classical conditioning
- Homeostasis: maintaining the body's internal equilibrium by initiating changes in physiology & behaviour
- it's a special case of classical conditioning where the body learns to anticipate & counteract biologically relevant events
- French physiologist Claude Bernard (1813–1878) observed that every organism’s internal environment interacts with a larger external environment.
- body works to maintain things like temp, glucose, & ion levels within strict parameters
- physiological processes of homeostasis r made more efficient through classical conditioning
--> Ex, shortly after drinking sugary beverage, blood glucose will rise, insulin is released to take up excess glucose to regulate blood glucose & maintain homeostasis
--> overtime the sweet taste (CS) alone might elicit insulin release (CR) to prepare the body for the expected rise in blood glucose
--> in this case, insulin= compensatory response
62
Regulating Body Temp
- human body temp can fluctuate within a normal range of 35–39˚C
- A core temperature that falls below (hypothermia) or rises above (hyperthermia) this range can be lethal.
63
A compensatory response is
a process which counteracts a challenge to homeostasis
- ex, insulin release after drinking sugary drink
- This compensatory response explains how people grow tolerant to drugs they take repeatedly.
64
Classical conditioning allows the body to _______________________. Explain
prepare for challenges to homeostasis
- Ex, if you drink a coke everyday, it becomes a CS that predicts the spike in blood sugar that follows. Eventually, the flavour alone cues the CR of insulin release
65
What happened when a colleague switched from coke everyday to Diet Coke to lose weight?
- he acc gained weight
- cuz the sweet taste of the coke stayed the same --> cuz contingency was so strong, he was still experiencing the conditional insulin release
--> this extra insulin acc led to decease in blood sugar now & his body struggled to restore homeostasis --> easiest way to restore it was to induce hunger & he started eating more, gaining weight
66
In classical conditioning terms, the various naturally occurring effects of the drug r collectively the ____________. These drugs r a challenge to _____________.
unconditional stimulus, homeostasis
67
Drugs often induce physiological changes that take our bodies out of balance. How does the body combat this?
- after some stimulus knocks body out of balance, compensatory responses work to restore homeostatic levels
- Ex, when morphine decreases respiration & decreases pain sensitivity, body counters with UR increased respiration & increased pain sensitivity.
68
Over many drug taking trials...
...conditioned stimuli in the environment become paired with the drug effects & a contingency is formed
--> these CSs may include cues from the location of drug taking & paraphernalia used to administer the drug --> the presentation of environmental cues will be enough to trigger a CR
69
Drug withrawal responses
- aka drug preparatory responses
compensatory responses help body prep for drug effects --> why a morphine addict confronted with empty syringe will suddenly experience extreme discomfort, pain, & nausea --> bodies seem to prep for drugs followed by the environmental cues = drug withdrawal responses
70
The brains of addicts respond to taking the drug, but also to drug-associated cues. ELABORATE
- there is increased activity at anterior cingulate cortex
70
Suppose that u give a regular drug consumer the following: the same amount in same environment, same amount in diff environment, & saline in conditioned response
- same: low response
- diff: high response
- saline (neutral substance): even lower response--> when a neutral substance is given in in the conditioned environment, u experience even more pain as opposed to not getting any drugs @ all
71
Drug tolerance is
the decreased effectiveness of a drug over the course of repeated administration
- Traditional view: Drug tolerance is usually explained by physiological changes, such as altered receptor sensitivity from repeated drug use.
- New model (classical conditioning view): Each drug administration = conditioning trial.
- To maintain homeostasis, the drug’s effects r counteracted by other physiological responses
- The drug’s effects= US
- The body’s compensatory responses= UR
- The environmental cues present during drug use (e.g., room, needle)= CS
- Over repeated pairings, the CS alone elicits a conditioned response (CR) --> learned counteraction explains drug tolerance: the body prepares to offset the drug before it’s even taken.
72
Dr. Sheperd Siegel
- After getting Ph.D. from Yale University, in 1968 Dr. Sheperd Siegel joined the Department of Psychology @ McMaster.--> His best-known work involves drug tolerance
- in 1976 he published a landmark study arguing that classical conditioning also plays a vital role --> He posited that a drug’s effect depends on the specific environment it is administered in, & thus one’s external environment impacts the likelihood of drug overdose
- Much of his other work followed a similar theme: unifying various forms of learning under the far-reaching principles of classical conditioning
73
Morphine experiment background
- US: Morphine’s effects (↓ pain sensitivity, ↓ breathing rate).
- UR: Body’s counteraction (↑ pain sensitivity, ↑ breathing rate).
- CS: Environmental cues of drug use.
- CR: Same counteraction triggered by environment alone.
Prediction: Morphine tolerance is environment-specific — rats will show tolerance in the familiar drug environment, but stronger drug effects in a new environment where the compensatory CR isn’t triggered.
74
MORPHINE EXPERIMENT: Method
- 10 trials total:
- 1st 8 trials: Tolerance acquisition phase--> morphine administered in either Environment A or Environment B. --> some rats built tolerance in Environment A & others in Environment B
- Last 2 trials: Tolerance test phase — drug effects measured in same or diff environment.
- Control groups: treated same but received saline instead of morphine.
- Tolerance Testing Phase: Analgesic (pain-relieving) effects of morphine were measured in both environments; test order was counterbalanced.
75
MORPHINE EXPERIMENT: Results
- Rats receiving morphine showed gradually reduced pain relief over trials → tolerance developed in that environment.
- Control rats (receiving morphine for the first time in test phase) showed strong pain relief, confirming no tolerance.
- When tested in a diff environment, morphine produced a stronger analgesic effect → tolerance was environment-specific.
- Supports the classical conditioning model: environmental cues act as conditioned stimuli that trigger compensatory responses.
76
MORPHINE EXPERIMENT: Discussion
- Traditional receptor-based theories predict tolerance regardless of environment, but results show environmental cues play a critical role in drug tolerance.
--> highlights a shortcoming of classical conditioning as it pertains to improving our lives --> when same amount of a drug is administered in a diff environment, the cues that normally elicit counteraction r not present, leading to overdose & sometimes death.
- Context-dependent tolerance demonstrates that learning (conditioning) contributes to physiological adaptation.
77
MORPHINE EXPERIMENT: Limitations
- No pre-test for baseline pain tolerance → individual diff not controlled.
- Small sample size (12 rats per group) may limit reliability.
- Only male rats used — results may differ in females.
- Only morphine tested — need to examine if findings generalize to other drugs or painkillers.
78
SLIDES: enigmatic overdose
- an overdose that happens in puzzling or unexpected circumstances--> ex when an experienced user takes their normal does yet dies
79
Classical Conditioning: Conclusion
- These simple principles of learning played a critical role in the history of psychology.
- Indeed, they formed the dominant paradigm in experimental psychology from 1920s to mid-1960s.
- Most aspects of human behaviour were assumed to be driven heavily by experience, & so psychology was filled with similar learning-based theories --> Early memory researchers theorized that memories were formed similar to conditional responses: via the association of stimuli occurring close in space and time.
-By this behaviourist view, the formation of memories & conditional responses rely on a purely mechanical process whereby the learner is basically a passive recipient of stimuli, acting reflexively.
- This view is now seen as oversimplified, cuz it neglects the role of inner mental processes experienced by the learner.
-Robert Rescorla (1988) stated, "Conditioning is not a stupid process by which the organism willy-nilly forms associations between any two stimuli that happen to co-occur. Rather, the organism is best seen as an information seeker using logical and perceptual relations among events, along with its own preconceptions, to form a sophisticated representation of its world.”
- Classical conditioning therefore lays the foundations for higher-order mental processes.
80
why were relapse rates so low in returning Vietnam War vets?
- new environment --> less craving
81
4 things to know about CC
1. CC generates multiple responses.
2. CC establishes preferences AND aversions.
3. CC underlies various psychological
conditions.
4. Pairing the US and CS is NOT sufficient for conditioning to occur (see textbook).
Psych 1X03
flashcards
Decks in class (13)
# Cards
-
Research methods 1107
-
Textbook: Intro: foundations of psych11
-
Classical Conditioning82
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Instumental conditioning69
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Problem Solving & Intelligence65
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Language82
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Categories & Concepts57
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Science of learning22
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chapter 7 textbook: Attention0
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Attention!73
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Influence of others oney158
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Forming Impressions (HEHE)69
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Memoryyyyyyyyyyyyy106
