Download Classical Conditioning

8/3/2009
Classical Conditioning
Conditioning is the process of
learning when behaviours, events
and stimuli become associated with
each other.
*Pavlov’s dogs learned to associate
two stimuli together, (the assistant
with food).
Classical conditioning: accidental
discovery.
• Initially, Pavlov was interested in the
digestive system of dogs and was
conducting experiments as to how much
saliva was produced by dogs when exposed
to food.
• In doing this research, he noticed that the
dogs began to salivate on the routine cue of
the lab. assistant entering the room before
feeding occurred.
…this is a natural response.
• Initially saliva flowed whenever food
was present which was a natural
involuntary reflex to the food stimulus.
How do you think the dog will respond if the
same lab. assistant feeds it on entering the
lab?????
=
With repeated trials a dog will associate
assistant with food…
….so the dog will begin
to salivate when he sees
assistant.
PLUS
&
=
1
8/3/2009
Eventually the dog will salivate at the sight
of the assistant entering lab….
=
Classical Conditioning
Conditioning = learning to associate
two things together.
• It’s just like when we get the
cat food out, the cat has
learned to associate the tin
with the food and they
respond to you getting the tin.
He gets excited because he associates the
lead with a walk
• Can you think of some examples
of when we have learned to
associate one thing with
another?
EG. When you get the dog’s lead,
what does the dog do? Why?
Are we conditioned when..
• What about
this?
• What do we
associate this
sound with?
2
8/3/2009
Classical conditioning…
What do you associate this with?
• Can you think of other
examples????
Are we classically conditioned…….?
How does classical conditioning fit
with class announcements?
We make an association. What
with?
ARE WE CONDITIONED?
• The announcement and??????
….
• ……the bell to pack up and leave.
• We are just like Pavlov’s dogs
when they associate the assistant
with the food….
3
8/3/2009
BUT these examples are not true
classical conditioning..
• What do you associate this sound
with?
• And yes, you guessed it. You have
just been conditioned.
• HOW?
Back to Pavlov and…
• …. those salivating dogs.
Then they taught the dogs to respond to a bell by repeatedly
presenting the bell with the food as occurred with the assistant.
Initially the bell was a neutral stimulus
NO response
No salivation
Food
Unconditioned
response.(UCR)
Dog Salivates
• Why, well we will deal with that later but
for now…..
What had Pavlov’s dogs learned?
• Due to being repeatedly exposed to the two stimuli
together, the dogs had learned to link the two stimuli
(lab assistant & food) and thus the lab assistant
stimulated the response before the food stimulus.
• A stimuli is any event that elicits (produces) a
response from an organism.
• A response is a reaction, by an organism, to a
stimulus.
Repeated exposure to bell with
food leads to…
Bell
+
food Which leads to unconditioned response.
(repeatedly)
UCR
Salivation
THEN, the dog learns (ie, is conditioned)…
Leads to conditioned response.
Bell
only
CR
Salivation
4
8/3/2009
CC is about associating two
stimuli…
Classical Conditioning.
* That is, the dog learned to associate the bell
with the food and began to salivate on
hearing the bell.
So initially the
• Bell = neutral stimulus (NS)
• Food = unconditioned stimulus (UCS)
Then by presenting the food + bell
repeatedly lead to the
• Bell = conditioned stimulus (CS)
To sum up…
• Classical conditioning refers to a learning
situation in which a certain unconditioned
stimulus (UCS) that evokes an automatic,
unconditioned response (UCR) is paired over a
series of trials, with a neutral stimulus (NS)
that does not usually produce this response
Remember, there are only two things that change:
* The bell (stimulus) changes from aNeutral Stimulus (NS)
Conditioned Stimulus (CS)
* The response changes from a –
Understanding the terms helps…
•
•
•
•
•
Neutral = no effect/ no relevant reaction.
Conditioned = learned.
Unconditioned = unlearned/automatic/innate.
Stimulus = something that evokes a response.
Response = reaction/behaviour.
Factors affecting classical conditioning
responses:
• The UCR has to be an involuntary response
which we have no control over.
• Similarly, the UCS should be a stimulus that
evokes a response with no prior (requisite)
learning.
Unconditioned Response (UCR)
Conditioned Response (CR)
5
8/3/2009
Hhhmmmmmm …maybe, maybe
not.
• So, knowing this were my phone ringing, drill
sound and announcements and what we
associate then with classical conditioned
responses?
• Why or why not?
• The text seems to contradict itself here….we’ll
see why later.
Factors affecting classical
conditioning responses:
• ALSO,
• in order for a paired association to occur, the
NS and the UCS have to occur close together
(0.5 of a sec. apart).
Processes in classical conditioning:
acquisition.
• When two things occur together, we associate one
with the other so that when one appears we expect
the other to follow and react accordingly.
Within classical conditioning, the acquisition process
is when an association is being formed between two
stimuli such that both will trigger the same response.
Processes of CC involve:
•
•
•
•
•
Acquisition
Stimulus Discrimination
Stimulus Generalisation
Extinction
Spontaneous recovery
Processes of C.C: discrimination
• Discrimination occurs in CC when an organism
only responds to the conditioned stimulus
(CS), but not to any other stimulus which is
similar.
• EG Pavlov’s dogs only respond to the bell they
were used to and no other bells.
6
8/3/2009
Processes of C.C.
• Stimulus discrimination is the ability to
perceive the difference between two or more
stimuli, even if they are similar in nature.
• EG Two bells that sound different
Processes of CC: generalisation
• Stimulus generalisation is when stimuli that
are similar will elicit the same response.
• EG. Two similar bells evoke the same
response.
Processes of cc: extinction
Processes in CC: spontaneous
recovery
• Extinction entails the termination of the conditioned
response. In CC , extinction occurs when the
reinforcer, in the form of an unconditioned stimulus,
is removed causing the association between the
conditioned stimulus (CS) and the conditioned
response (CR) no longer occurs.
i.e. The learned b/r has died out.
• After extinction has occurred, spontaneous
recovery may be shown by the reappearance
of a conditioned response (CR).
Ie. Sometimes the CR reoccurs despite the
response being extinguished for some time.
Can you think of an example?
CC of Behaviour p 446
Conditioned reflexes…
• Classically conditioned b/rs are like reflexes in
that they occur involuntarily.
BUT
Unlike reflexes in that CC behaviours are
learned.
• A conditioned reflex is an automatic response that
occurs as a result of previous experience. This
learning takes little effort.
• EG learning that the brake lights on the car in front of
you means the car will slow down, therefore you
slow down. Our braking as a result of the brake lights
is equal to Pavlov’s dogs salivating at the bell. Ie ,we
learn to respond to the brake lights.
7
8/3/2009
Examples of CC…
• Think of my previous examples of when we
have learned to associate two things and this
then evokes a response from the previously
neutral stimulus……….
(Class has a go, then see next slide)
Other ways CC applies in our lives…
• Conditioned emotional response
(EG. controversial experiment: “ Little Albert.”)
CC in practice:
• Aversion therapy
• Systematic Desensitisation
• Bedwetting treatment
Example of CC….
EG. Sound of dentist’s drill
cringe.
Ie. The sound of the dentist’s drill is associated with
potential pain.
THUS, the drill sound was a neutral stimulus but when
associated with the pain of getting a tooth drilled, we
respond to the sound as we would to the drilling of
our tooth ....the drill becomes the conditioned
stimulus.
Examples of CC learning.
• Announcements before bell
pack-up.
Phone rings
answering it.
Text msg sound on phone
seeing what’s
there.
Lights dim in theatre
being quiet.
CC in our lives…
Consider learned emotional responses. A
“conditioned emotional response” is an
emotional reaction that usually occurs when
the autonomic nervous system produces a
response to a stimulus that did not previously
trigger that response.
Classical conditioning benefits &
harm…
• We can benefit from learning to associate two
stimuli – eg. drugs , spiders and harm.
• It can also have disadvantages. For example,
learning to fear animals or cuddles.
8
8/3/2009
Research: controversial “Little Albert”
experiment.
• Classical conditioning was used to teach “Little
Albert” to fear a white rat.
• Initially Albert had no fear of the rat..
Poor Little Albert….
BUT
The rat was then shown to Albert
along with a startling loud noise.
Albert learned (was conditioned)
to fear the rat because he made
the association between the rat
and the noise.
“Little Albert’s” learned
emotional responses
Albert’s fearful
responses
were generalised to:
- rabbit
- seal skin coat
- dog
Ethical issues…
“Little Albert.”
Albert was not was not given the opportunity to
have the conditioning extinguished (removed).
• ALSO… Albert’s mum may not have been fully
aware of what the experiment involved.
• What other ethical issues were there??
9
8/3/2009
“Little Albert.”
• Although little Albert was exposed to severe anxiety,
Watson and Raynor. (experimenters) did not cease
the experiment.
• What’s this ethical issue called?
• A.P.A., at this time, was in its formative years thus
the code of ethics and standards had not been
established.
Classical Conditioning in
practise…..
CC can be used in therapy to help people:
• eradicate bad behaviours, like alcoholism.
• systematically desensitise (replaces a
conditioned response with a relaxation
response).
• therapy for bedwetting.
CC in practise: aversion therapy.
Aversion therapy in CC
• Aversion therapy is a form of behaviour therapy that
applies CC principles to reduce or stop an unwanted
behaviour by associating it with an unpleasant
stimulus. Habits such as gambling and smoking, and
obsessions such as compulsive hand washing,
alcoholism, and eating disorders are all examples of
harmful behaviours.
• For example, medicinal drugs are paired with alcohol
consumption to make an alcoholic feel nauseous.
The alcohol becomes the conditioned stimulus (CS)
having been neutral initially, to the extent that it did
not originally cause any nausea. However, after
repeatedly pairing it with a nausea inducing drug
(drug=UCS, nausea-UCR), a mental association is
soon established between the two stimuli.
Systematic Desensitisation in CC
Making associations between
stimuli…
• Systematic desensitisation is a type of
behaviour therapy that uses CC principles to
get rid of anxiety or fear response with
relaxation response. The procedure requires
the patient to associate the feeling of being
relaxed with the stimulus that has been
causing the fear and anxiety.
• The pairing of a relaxing stimulus with the anxiety
producing stimulus occurs over a series of steps. The
first of these steps uses a least frightening aspect of
the situation or object that causes the fear and the
following pairings use increasingly fearful aspects so
that the patient moves through a series of graded
steps to overcome their fear.
10
8/3/2009
Bedwetting. How can CC help?
Ethics in CC.
• Bedwetting (enurisis) is another problem commonly
treated with CC principles.
• The normal UCS (pressure of full bladder) to wake us
fails. In order to train the person to wake before
wetting, a special blanket is used which buzzes loudly
when the first drop of urine wets the blanket. This
awakens the person in time to go to the loo.
• Now, as a class, read from the text “Ethical Issues in
Conditioning Behaviour. “ p454-456
• Next slide for
code of ethics
points.
Australian Psychological
Society’s….
•
•
•
•
•
•
•
Code of ethics:
Confidentially
Voluntary participation
Informed consent
Withdrawal rights
Deception
debriefing
Taste aversion…
• Taste aversion is a learned response in which
an organism associates a particular taste of a
food with feeling ill, due to a one-off
experience.
• How is taste aversion a CC style of learning?
• How is it NOT a CC style of learning?
One trial learning and taste
aversion & CC…
• One trial learning is a particular type of learning that
involves a change in behaviour as a result of one trial
or event. It is generally a conditioned physical
response that is classically conditioned. It results
when the outcome for the for the organism is
particularly significant. That significance may be
associated with something extremely unpleasant.
TASTE AVERSION...is it a CC?
• It is a CC style of learning in that there is an association made
between a stimulus and a response, eg, oysters and getting
sick.
• CC and taste aversion are passively learned
BUT
• it is NOT a style of CC learning in that it only takes ONE trial
and CC usually has repeated trials
• PLUS it is not extinguished as easily as CC learning can be
extinguished by not pairing the two stimuli for a few trials.
• Can you find other reasons why it is not CC????
11
8/3/2009
Another reason why taste aversion
is not a CC….
• One trial learning (EG. taste aversion) are
learned quickly and the association made is
very powerful.
• CC requires a number trials with the two
stimuli to make the association.
Research: Garcia
• Garcia argues the taste aversion is not a
typical CC learning.
• Garcia says learned taste aversions can serve
the purpose of being adaptive…..
• How do you think it is adaptive????
AVOID
POISON
How is taste aversion adaptive?
• Animals quickly learn what NOT to eat thus
enhancing their survival…….
Taste aversion enhancing
survival….?
• The CS for each group were the flicking lights,
clicking and saccharine flavour.
• Had the rats learned to avoid all parts of the
CS or just some of them????
• To cut a long story short……the UCS (feeling
ill) influenced what the rats had learned….
One-trial learning (taste aversion
rat experiment)
• In two experimental conditions, rats were given
saccharine-flavoured water and, while drinking this,
lights flickered and a clicking sounds were
administered.
• Later, either electric shocks or illness-inducing x-rays
were given. All rats then had an aversion to
saccharine flavoured water…..
Taste aversion….
• The rats had associated stimuli in ways that
foster survival
12