Title: LEARNING
1LEARNING
MECHANISMS OF LEARNING
2DEFINING LEARNING
- Humans are born very poorly equipped for
independent survival and must spend most of the
first 10 to 15 years of their lives learning to
survive. - The word learning refers to the relatively
permanent changes in behaviour and cognition as a
result of experience. - It is ongoing, adaptive, can be intentional or
unintentional, active or passive.
3Learning is relatively permanent
- Learning is defined as being relatively permanent
because it cannot be something that is present
one moment and gone the next, or here today and
gone tomorrow.
4Learning can be intentional or unintentional
- Learning can occur intentionally such as when
someone makes the choice to learn how to play the
piano and takes lessons. - Learning can be unintentional such as while
watching or hearing someone else playing the
piano.
5Learning can be active or passive
- Learning can be active, such as reciting your
times tables in order to remember them. - Learning can be passive, such as when hearing
about an important event on the news or reading
something in the newspaper.
6Learning is a change in behaviour
- The notion of change is an important part of the
definition of learning, because something must be
different about the organism after learning has
taken place. - This change may be immediate, or it may be
delayed and occur over a period of time after the
learning.
7BEHAVIOUR NOT DEPENDENT ON LEARNING
- Learning accounts for most of the behaviours that
are observed in humans and animals, however not
all behaviour has to be learned. - What are some behaviours you can think of that
are not learned?
8BEHAVIOUR NOT DEPENDENT ON LEARNING
- Reflexes
- Fixed-action patterns
- Maturation
9REFLEX ACTIONS
- Automatic, involuntary behaviours that do not
require prior experience and occur in the same
way each time are known as reflexes. - - Blinking when wind blows in your face
- - Moving your hand from a hot object
- Reflexes allow people to deal with specific
stimuli that are important for their protection
or survival through rigid, automatic responses.
10- We are born with a large number of reflexes, most
of which disappear or are incorporated into other
behaviours within the months after birth.
11FIXED-ACTION PATTERNS
- A fixed-action pattern of behaviour occurs when
all members of a species produce an identical
response to the same specific environmental
stimuli. - The mechanisms that control the behaviours are
fixed, in that they are genetically programmed
into the animals nervous system and appear to be
unable to be changed as a result of learning.
12- A fixed-action pattern of behaviour is a
behaviour inherited by every individual member of
a species, or if the behaviour is sex-specific,
by all members of one sex in the species. - Fixed-action patterns differ from reflexes in
that a reflex, although inborn, usually consists
of a single or simple response, whereas a
fixed-action pattern is more complex, usually
consisting of a sequence of responses. - Eg. Salmon migrate thousands of kilometres
through ocean waters to spawn in the rivers in
which there were born.
13- A behaviour is considered a fixed-action pattern
when - All members of the species demonstrate the
behaviour - The behaviour is similar whenever it is executed
- When the organism reaches a certain maturity it
will produce the behaviour the first time it is
required, without having learnt it - The behaviour is difficult to change
- The behaviour is complex, it follows a sequence
and appears without the organism having an
opportunity to learn it.
14Examples
- Courtship of a Teminck Tragopan
- The mating dance- A must see!!!!
- Blue footed booby mating dance.
15BEHAVIOUR DEPENDENT ON MATURATION
- Maturation is a developmental process leading
towards maturity, based on the orderly sequence
of changes that occur in the nervous system and
other bodily structures controlled by genetic
inheritance. - These behaviours generally appear at predictable
times in development. - Crawling at 8-10 months of age.
- During puberty, the change in a boys
voice-becoming deeper.
16Learned, reflex, FAP, maturation or mixture?
- Emotional attachment by an infant to a caregiver
- Speaking in a high-pitched baby voice to an
infant - Being scared of snakes
- Scratching an itch
- Nodding in agreement
- Smoking cigarettes
- Perceiving an illusion
- Whistling
- Walking
- Playing
- Curiosity
- Sleeping
- Loving
- Roller-skating
17Learning curve experiment
- Write operational hypothesis
- Page 427
18Learning and changes in the brain
- The ability to learn and retain what is learnt in
memory distinguishes organisms with greater brain
capacity. - When higher order animals learn, different parts
of their brains become active, depending on the
type of learning that is taking place. Eg skill
vs factual information.
19- The nervous system, and therefore the brain, is a
living organ that grows and changes continuously. - The brain is made up of approximately 100 billion
neurons and each neuron is linked to as many as
15,000 others. - Millions of neurons send messages at the same
time. - The research by Kandel with aplysia was
pioneering in this area.
20Brain areas involved in learning
- Some key areas of the brain that are more
responsible for learning include - the hippocampus
- the amygdala
- the cerebellum
- lobes of the cerebral cortex.
21Brain structure Role in learning Effect of damage on ability to learn
The cerebellum
Hippocampus
Amygdala
Frontal lobes
22The Cerebellum
- The cerebellum is a structure attached to the
rear of the brain stem that helps coordinate
voluntary movement and balance. - It primarily regulates posture, muscle tone and
muscular coordination. - It also stores memories related to skills and
habits (procedural memories) - Eg. Rats reared in a stimulating environment that
encouraged exercise had a larger cerebellum on
average than rats that were raised in small
cages.
23- Damage to this structure results in difficulty in
motor learning and disorders in fine movement. - It also leads to difficulty learning new
procedural skills.
24The Hippocampus
- Earlier we discovered that the hippocampus is
involved in formulating new memories of facts and
episodes. - The hippocampus is also critical to spatial
learning and awareness because it plays a role in
monitoring locations in space. It is the brains
geographer. - When damaged these functions can be severely
effected.
25The Amygdala
- The amygdala is a bundle of neurons connected to
the brain stem and the cortex. - Its main function is to aid survival, and it is
involved in the memory and learning of emotional
responses, particularly aggression and fear
(fight-flight response) - It can also assist in the storage of declarative
memories when they are associated with emotion.
26- Humans with damage to this area experience
abnormal fear responses. - They will not display the physical signs of fear.
27The frontal lobes
- Frontal lobe functioning is crucial for learning,
memory, planning, problem-solving, speech
production and the execution of daily activities.
- It is also heavily involved in motor functions.
- When damaged a persons ability to plan and their
motivation may be effected.
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29Phases of neural development in learning
- Most researchers agree that when learning takes
place a physical change occurs in the synapse
between neurons. - These changes result in the laying down of new
neural circuits, or neural pathways, through
which information can travel around the brain. - If we are to process information and learn from
it, the first thing that must happen in our brain
is that the neurons must be able to communicate.
30Neuron formation Laying the groundwork
- Life begins with a single cell. This cell divides
to form to other cells which then divide again
and start to multiply. - This process continues until an organism is
formed. - The cell, whilst multiplying, must also
differentiate. This means some will become muscle
cells, some will become support cells for neurons
and so on.
31- These different types of cells must then make
their way to the appropriate sites in the
organism and line up with other cells to form
particular structures. - They then create relationships with the cells
around them. - In other words they must form synapses with one
another in a process called synaptogenesis.
32Synapse formation Synaptogenesis and its link to
learning
- As we know, different parts of the brain have
different functions and the links (neural
pathways) between them need to be built and
maintained. - During learning, nerve cells grow new connections
and form new synapses, or existing synapses are
strengthened. - Information is then able to pass from one neuron
to the next.
33- Not all brain neurons have synaptic connections
with other neurons when we are born- the synapses
(connections) must form as our brain continues to
develop. - Once the neurons have migrated to the appropriate
part of the body they will grow axons (fibers
that carry information away from the cell body)
and dendrites (fibers that receive incoming
messages). - Synaptogenesis is the term used to describe the
formation of synapses between neurons.
34- Synaptogenesis then occurs when the axons and
dendrites reach out and link with a target cell. - This process occurs throughout a healthy persons
lifespan, but it occurs most rapidly during early
brain development, beginning about two months
before birth until about two years after birth. - It allows us to form new connections between
neurons to establish the pathways that allow
different brain areas to communicate.
35- The synaptic changes that take place within a
neural pathway during learning are believed to
have long-term potentiation. - Long-term potentiation refers to the long-lasting
strengthening of the synaptic connections of
neurons, resulting in the more effective
functioning of the neurons whenever they are
activated. - Neurons that fire together, wire together
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37Effects of experience on neural development
- Genetically, a cell may be programmed to find its
target cell and establish a synapse. - Even so, many potential synaptic connections are
lost and up to 50 of neurons die during the time
of synaptogenesis. - This means that it is not genetics alone that
determines neural development- the external
environment is also an important part.
38- Use it or lose it.
- The main principle that guides environmental
neural development is that by making use of a
function we strengthen neural connections,
however those neurons that are not activated by
experience will not survive. - Eg. Animals reared in the dark have fewer
synapses and dendrites in their primary visual
cortex than animals reared in their natural
environment. - This shows that learning through experience can
play a big role in how our synapses form.
39The role of neurotransmitters in learning
- Learning involves the introduction of experience
or new information, which produces changes in
neurons and neural networks. - Through learning, new synapses grow and existing
synapses form closer links. - Neurons must communicate over the synapse because
neurons are not joined to one another. - How does a message travel across the synapse to
another neuron?
40- The nerve impulse within a neuron is primarily
electrical. That is why behaviour is effected
when the brain is electrically stimulated (ESB). - Communication between neurons is chemical so
messages are sent between neurons chemically. - The sending neuron is known as the pre-synaptic
neuron (before the synapse). - The receiving neuron is known as the
post-synaptic neuron (after the synapse).
41- When an electrical charge in the form of a nerve
impulse, or action potential, sweeps down the
axon, neurotransmitters are released into the
synapse. - Neurotransmitters are chemicals released at the
axon terminal of the pre-synaptic neuron. - They carry the chemical messages across the
synapse (synaptic gap) to the dendrite on the
post synaptic neuron.
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43- Neurotransmitters may act in one of two ways when
they arrive at the post-synaptic neuron. - Transmitters may excite the post-synaptic neuron
or inhibit it. - At any instant, a single neuron may receive
hundreds or thousands of messages from adjacent
neurons. However, whether the result of
transmission will be excitory or inhibitory
depends on the neurotransmitter used.
44- If the neurotransmitter has an excitory effect it
will stimulate or activate a neural impulse in
another neuron. - If it has an inhibitory effect it will block or
prevent the receiving neuron from firing.
45Neurotransmitters
- NMDA (N-methyl-D-aspartate) is a neurotransmitter
receptor found on the dendrites of neurons,
particularly neurons in the hippocampal area. - It is specialised to receive the neurotransmitter
glutamate. Together with NMDA, glutamate is
important for long-term potentiation.
46- Dopamine- is a neurotransmitter thought to
contribute to attention, learning and motor
movement. Reduced dopamine levels can lead to ADD
and Parkinsons disease. Excess dopamine has been
linked to schizophrenia. - Norepinephrine- is secreted by the neurons of the
sympathetic nervous system. It influences the
amount of alertness in the brain, controls hunger
and is involved in learning and memory. Lower
levels have been associated with depression.
47Plasticity Rewiring the brain
- Research suggests that the human brain can be
moulded and changed throughout the lifespan. - This is known as plasticity.
- Plasticity is the ability of the brain to change
its structure and relocate functions to different
areas and/or neuronal networks.
48- There are three examples of when plasticity can
occur - At the beginning of life, when the immature brain
organises itself. - In case of brain injury, to compensate for lost
functions or maximise remaining functions. - Throughout life, whenever something new is learnt
or memorised. - - Research example pg 435
49Developmental plasticity
- Developmental plasticity refers to changes in
neurons and synaptic connections that occur as a
specific consequence of developmental processes. - When the brain is developing, dramatic changes
occur in the number of neurons in the brain.
50- Remember
- During development of the nervous system cells
divide, differentiate, extend axons and
dendrites, and form synapses. - Synaptic connectivity (synaptogenesis) will grow
and develop. - Synaptic responses can also change, and the
post-synaptic response to the release of
neurotransmitters can become stronger or weaker.
51Adaptive plasticity
- The brain is not only capable of plasticity
during development but also throughout adult
life. - The major structures in the brain are similar for
everyone but subtle differences between the
brains of individuals results from the fact that
it is adaptable and able to modify its circuits
throughout life. - This is what makes us individual, flexible and
efficient.
52- The brain is capable of re-wiring itself after
some types of damage. - It also forms new connections in response to
changing environmental conditions as well as
neural changes influenced by learning. - This is called adaptive plasticity.
53- Adaptive plasticity is a term referring to the
ability of neurons to alter the connections
between the synapses in accordance to best suit
the environmental conditions, when learning
something new, or when re-learning something
after brain injury.
54- Learning a new skill such as playing the piano,
requires many changes in the brain. Some
dendrites grow longer and stronger while others
are pruned away. - By doing this parts of the cortex are rewired
and tuned to carry out tasks more efficiently. - The brain of a musician is distinctly different
to the brain of a person with no musical
training. - Over the course of a lifetime, our experiences
literally shape, mould and remodel details of the
brain.
55- When damaged the brain has a remarkable ability
to adapt and change to compensate for damage. - Eg. Stroke victim.
- It appears that the functions effected by damage
transfer themselves to regions of the brain that
are unaffected by the stroke.
56Implications of brain plasticity
- How do we use this to our advantage?
- Using your brain in novel or stimulating ways
actually increases its size and the number of
dendrite branches it contains. - The more you challenge and engage your brain, the
healthier it will be and the better it will
function.
57Timing of experience and critical periods
- Why do some experiences have more lasting effects
than others? - Part of the answer lies in the concept of
critical periods. - A critical period is a time of increased
sensitivity to environmental influences when the
conditions are optimal for certain capacities to
emerge in an organism.
58- Events that occur in the critical period can
permanently alter the course of development. - Eg. If a pregnant woman contracts German measles
in early pregnancy the child may be born with
heart defects, cataracts or hearing loss. If the
measles were contracted in the later stages of
pregnancy the baby would not be damaged. - Often certain events must occur during a critical
period for a person to develop normally.
59- Research conducted by Weisel and Hubel in the
1960s showed that if a newborn kitten has its
eye stitched shut early in its development the
kitten will become permanently blind in that eye.
If the eye is sewn shut later in development the
kitten will not become blind in that eye. - This shows that there must be a critical period
for the development of vision in kittens and if
this does not occur the result will be blindness.
60- Children have far more plasticity than adults
which would imply that critical periods are
important in development. - Draw timeline.
61Evidence in support of plasticity
- Evidence supports the theory that when you become
an expert in a specific skill, the areas in your
brain that deal with that type of skill will
grow. - Eg.
- The left parietal lobe is larger in people who
are bilingual than people who speak only one
language.
62- Eg.
- Professional musicians (who practise at least one
hour per day) have a higher volume of grey matter
(cortex) than amateur musicians or people who
play no instruments at all. - There have been observed changes in the brains of
students studying for exams. When compared with
students not studying for exams those who were
studying showed learning induced changes in
regions of the brain associated with memory and
learning.
63- Over the past decade there has been progress in
research that has demonstrated evidence of
adaptive plasticity. - It has shown that functional and structural
changes take place in the cerebral cortex after
injury. - This means that the structure and function of
undamaged parts of the brain can take over the
functions of the injured part. - This process takes place during recovery and is
often influenced by rehabilitation. - Taxi drivers experiment.
64Imaging the learning brain
- Brain imaging technologies show that during
learning, changes occur in neurons that can
result in permanent structural and functional
changes in the brain. - They also show how specific areas of the brain
are involved in different types of activities.
65- Functional brain imaging techniques allow us to
evaluate brain changes in response to learning,
development, disease and also recovery following
injury.
66THEORIES OF LEARNING
- There are many different ways to learn that are
not necessarily different from one another. - An individual can shift from one type of learning
to another in many real-life situations. - The form of learning that we will be looking at
is called conditioning. - Conditioning is the process of learning
associations between a stimulus in the
environment and the behavioural response. - Conditioning is to do with how learning occurs.
67- It is the process of linking events that occur
together. - The two main types of conditioning are classical
conditioning and operant conditioning. - In classical conditioning we learn that two
events go together after we experience them
occurring together on a number of occasions. - In operant conditioning we learn by forming a
three-way association between a stimulus, a
response and the consequence of the response.
68- Other types of learning that we will be studying
- Trial and error learning
- One trial learning
- Insight learning
- Latent learning
- Observational learning
69 70Ivan Pavlov
- Russian psychologist Ivan Pavlov was the first to
describe classical conditioning as a learning
process when he was investigating the digestive
system of dogs. - He was particularly interested in the role of
salivary secretions in the digestion of food. - Today he is better remembered for his work on
classical conditioning.
71- Pavlov surgically moved the salivary gland of a
dog into its cheek, and put a tube into the gland
which was attached to a test tube. - The dog was placed into a harness to prevent any
sudden attempts to escape during the test period. - Pavlov knew that dogs would salivate if food was
placed in their mouths, but he noticed that they
would also salivate before they were given food. - At the time he believed that digestion involved a
series of reflexes, so he set out to discover
what stimulus caused this response of salivation
even before the dogs received food. -
72- Various stimuli were presented to the dog, and
the effects on its rates of salivation were
measured. - Pavlov noticed that the dogs began to salivate to
other stimulus other than the food. For example
when the lab technician entered the room to give
the dogs the food they began to salivate.
Salivation was caused by the lab technician and
not the food. - Pavlov began to test this using other stimulus
such as a bell, a musical tone, clapping, a
light - The dogs had learnt to associate different
stimuli with food which caused them to salivate,
rather than the food being the cause.
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74- Pavlovs experiments then provided clear evidence
of a type of learning that was based on the
repeated association of two different stimuli. - A stimulus is any event that elicits (produces) a
response from an organism. - A response is a reaction by an organism to a
stimulus. - In Pavlovs experiment the stimulus of food
initially produced the response of salivation.
Eventually though the sight or sound of the
technician became the stimulus that produced the
salivation response.
75- Classical conditioning refers to a form of
learning that occurs through the repeated
association of two (or more) different stimuli. - The salivation response is caused by the
autonomic nervous system which means it is an
involuntary reflexive response. - The salivation has become associated with, and
conditioned to, a new stimulus. - Learning is said to have occurred only when a
particular stimulus consistently produces a
response that it did not previously produce.
76Key elements of classical conditioning
- There are four key elements of classical
conditioning - The unconditioned stimulus (UCS) is any stimulus
that consistently produces a particular,
naturally occurring, automatic response. (Food). - The unconditioned response (UCR) is the response
that occurs automatically when the UCS is
presented. - It is reflexive, involuntary response that is
predictably caused by a UCS. (Salivation).
77- The conditioned stimulus (CS) is the stimulus
that is neutral at the start of the conditioning
process and does not normally produce the
unconditioned response. (Lab technician). - Through repeated association with the UCS, the CS
triggers a very similar response to that caused
by the UCS. - Association refers to the pairing or linking of
one stimulus with another stimulus- Lab
technician and food. - The conditioned response (CR) is the learned
response that is produced by the CS. (Salivation).
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79Classical conditioning example
- Flora has a cat name Tiger. Tiger loves eating
FishDelish, a brand of cat food, which Flora
feeds to Tiger every night. Flora is curious
about Tigers behaviour, and she wants to
understand how Tiger has come to behave and
respond in a particular way. - Floras routine when she comes home from work is
as follows she puts her keys on the kitchen sink
(which makes a clanging noise each time), then
she prepares Tigers dinner. - After several days of this routine, Flora noticed
that Tiger would run up to her and salivate
whenever she put her keys on the sink.
80BEFORE CONDITIONING DURING CONDITIONING AFTER CONDITIONING
Neutral stimulus (NS)
Unconditioned stimulus (UCS)
Unconditioned response (UCR)
Neutral stimulus (NS) Conditioned stimulus (CS)
Conditioned stimulus(CS) Conditioned response (CR)
Learning Activity 3 Identifying elements of
classical conditioning.
81KEY PROCESSES IN CLASSICAL CONDITIONING
- The key processes in classical conditioning are
- Acquisition
- Extinction
- Stimulus generalisation
- Stimulus discrimination
- Spontaneous recovery
82ACQUISITION
- In classical conditioning, each paired
presentation of the CS with the UCS is referred
to as a trial. - Acquisition is the overall process during which
the organism learns to associate two events (the
CS and the UCS). - During acquisition, the presentations of the NS
(becomes CS) and the UCS occur close together and
always in the same sequence.
83- The duration of the acquisition phase is
determined by how many trials is takes for the CR
to be learned. - The shorter the period of time between the
presentation of the UCS and the CS the faster the
acquisition. - Pavlov discovered in his experiments that it was
best for the pairing of the CS and the UCS to be
very close together. - The end of the acquisition phase is said to occur
when the CS alone produces the CR. At this point,
conditioning is said to have taken place.
84EXTINCTION
- A conditioned stimulus-response association is
not necessarily permanent. - The strength of the association may fade over
time or disappear altogether. - Extinction is the gradual decrease in the
strength or rate of a CR that occurs when the UCS
is no longer presented. - Some behaviours are extinguished quickly, others
take longer to extinguish.
85SPONTANEOUS RECOVERY
- Extinction of a conditioned response is not
always permanent. - Spontaneous recovery is the reappearance of a CR
when the CS is presented, following a rest
period, after the CR appears to have been
extinguished. - Spontaneous recovery does not always occur, and
when it does it is short lived.
86- The CR tends to be weaker than it was originally
(during acquisition). - If the extinction procedure is repeated several
times, eventually the CR will disappear
altogether and spontaneous recovery will not
occur at all.
87STIMULUS GENERALISATION
- Once an organism has learned to respond to a
conditioned stimulus, other stimuli that are
similar to the CS may also trigger the CR, but
usually at a reduced level. - Stimulus generalisation is the tendency for
another stimulus- one that is similar to the
original CS- to produce a response that is
similar (but not necessarily identical) to the CR.
88- The greater the similarity between stimuli, the
greater the possibility that a generalisation
will occur. - Eg. Instead of salivating to the sound of a
ringing bell the dogs would salivate to the sound
of a door bell. - The response is usually reduced if this occurs.
- Stimulus generalisation has a valuable adaptive
role (avoiding an open fire place when having
experienced a burn from a gas stove top), but can
also be detrimental in some situations (a dog may
snap at flies and then accidentally snap at a
wasp).
89STIMULUS DISCRIMINATION
- In classical conditioning, stimulus
discrimination occurs when a person or animal
responds to the CS only, but not to any other
stimulus that is similar to the CS. - Eg. If someone is afraid of a particular dog, but
is not bothered by any other breed of dog in a
similar situation.
90CLASSICAL CONDITIONING OF BEHAVIOUR
- Classical conditioning is one of the simplest
forms of learning. - Classically conditioned behaviours are like
reflexes in that they occur involuntarily,
however they are unlike reflexes in that they are
learned. - A conditioned reflex is an automatic response
that occurs as a result of previous experience. - A conditioned reflex requires little conscious
thought or awareness on the part of the learner.
91- By learning to associate stimuli in our everyday
experience, we gain information about our
environment, some of which we take for granted
but which is nevertheless valuable. - Eg.
- Packing up your books at the sound of the bell
for the end of the lesson - Answering the door bell or phone when it rings
- Listening for thunder after a flash of lightening
92- Conditioned reflexes include a range of
behaviours, one of the most researched is the
emotional response. - Sometimes an emotional response such as fear or
anger to a specific stimulus is learned through
classical conditioning. - 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. - Eg. Cringing at a dentist drill.
93- While it might be beneficial to form a fear of
something that could harm you, it may be
psychologically harmful to form a fear about
something that does not normally harm you. - Read Little Albert.
94ETHICAL ISSUES IN CONDITIONING BEHAVIOUR
- Confidentiality- a participants right to privacy,
meaning that in a study details about the
participants identity cannot be revealed unless
their written consent is obtained. - In Little Alberts case, his details were
published along with his photos in a research
article without the written permission from his
mother.
95- Voluntary participation- the researcher must try
to ensure that participants involvement in the
research is voluntary. Participants must not be
put under any pressure to take part in the study.
- Although Little Alberts mother did volunteer her
son to participate in the experiment on
conditioning, it is questionable whether she was
informed as to what was actually going to happen
to her son in the experiment.
96- Informed consent- wherever possible participants
must be appropriately informed of the nature and
purpose of the investigation. This must be
appropriately documented. - It is unlikely that Little Alberts mum was
properly informed about what was going to occur
throughout the experiment and the conditions that
she was agreeing to. There is no documented
paperwork to indicate otherwise.
97- Withdrawal rights- The researcher must inform
participants of the nature of the research and
that they are free to participate or to decline
to participate or to withdraw from the research. - Little Alberts mother was not with her child when
he was being conditioned and Little Albert was
too young to make the decision himself. Meaning
that even if he should have been withdrawn he
could not have. Related to the lack of informed
consent.
98- Deception- when it is necessary for scientific
reasons to conduct a study without fully
informing participants of its true purpose prior
to commencement, the researcher must ensure that
participants do not suffer distress from the
research procedure. - If Little Alberts mother was not informed about
the exact procedure for the conditioning
experiment there is an element of deception
involved. This is unethical as the experiment did
cause distress for Little Albert and his mother
was presumably not informed about this.
99- Debriefing- The researcher must provide an
opportunity for participants to obtain
appropriate information about the nature, results
and conclusion of the experiment. - According to the experimenters Little Alberts
mother moved away before the experimenters had a
chance to debrief her and reverse Alberts
conditioned behaviour. Other reports suggest that
although the experimenters knew well in advance
the mother was leaving, they did not attempt to
follow the debriefing guidelines.
100APPLICATIONS OF CLASSICAL CONDITIONING
- Classical conditioning is used in many
therapeutic settings, which aim to rid people of
undesirable behaviours. - Graduated exposure / systematic desensitisation
- Flooding
- Aversion therapy
101Graduated exposure
- In most cases, a classically conditioned response
will become extinguished if the UCS is not paired
with the CS at least occasionally. - Graduated exposure is a kind of behaviour therapy
that attempts to replace an anxiety or fear
response with a relaxation response through a
classical conditioning procedure. - This means the client must associate being
relaxed with the anxiety or fear stimulus by a
series of graded steps.
102- The procedure is as follows
- Teach the person to relax.
- Break down the fear arousing stimulus into a
series of graded steps. - Steps are graded from most fear arousing to least
fear arousing. - Eg. Consider a person with a fear of flying.
103Most frightening
- Experiencing mid-air turbulence
- Taking off
- Taxiing down the runway
- Boarding the plane
- Waiting to get on the plane
- Travelling to the airport in a car
- Buying a plane ticket
Least frightening
104- The therapist would then ask the patient to
visualise (imaginal exposure) the least
frightening scene on the list. When they can
imagine doing this they would be asked to imagine
the next step and so on. - In the end the patient should be able to imagine
the most fearful stimulus without becoming
afraid. - Real life exposure (in vivo exposure) is the most
successful or virtual reality technology could
also be used. - This eventually leads to the fear of flying being
eventually overcome.
105Flooding
- Flooding is another type of exposure therapy.
- Flooding involves bringing clients into direct
contact with the anxiety or fear producing
stimulus and keeping them in contact with it
until the conditioned response is extinguished. - It is believed that people will stop fearing the
stimulus during the exposure when they discover
it is quite harmless.
106- Like graduated exposure, flooding can be visual,
real-life or virtual reality. - A major criticism of flooding is that it causes
extreme anxiety for the individual.
107AVERSION THERAPY
- When people develop unwanted behaviours (that are
harmful) such as substance abuse, gambling
addiction or inappropriate sexual behaviours, it
is often difficult to help them permanently stop
the unwanted behaviour. - It is especially hard when the behaviour is
followed by a sense of pleasure or relief.
108- Aversion therapy is a form of behaviour therapy
that applies classical conditioning principles to
inhibit (block) or discourage undesirable
behaviour by associating it with an aversive
(unpleasant) stimulus. - This may be a feeling of disgust, pain or nausea.
- The aim is to suppress or weaken the undesirable
behaviour. - Eg. To stop nail biting- painting nails with a
foul tasting substance.
109- The association between the unpleasant stimulus
and the unwanted behaviour is learned very
quickly. - Aversion therapy was first used in the 1930s to
treat alcoholism, by giving alcoholics an
electric shock whenever they could see, taste or
smell alcohol. - Today instead of using electric shocks,
alcoholics are given nausea inducing drugs paired
with alcohol consumption to make the patient feel
ill. - UCS- NAUSEA DRUGS CS- ALCOHOL
- UCR- FEELING ILL CR- FEELING ILL
110- The limitation to this is that some alcoholics
will avoid alcohol while taking the drugs but
return to it once therapy is finished. - This means that the learned aversion often fails
to generalise to situations other than those
under which the learning takes place. Therefore
at times the results of aversion therapy are
often short lived.
111TRIAL AND ERROR LEARNING
112TRIAL AND ERROR LEARNING
- There are many types of learned behaviours that
cannot be explained by classical conditioning. - Classical conditioning is based on learnt
behaviours that are involuntary or reflexive. - Other learning theories describe the acquisition
of learnt behaviour that is voluntary.
113- We all adjust our behaviour according to the
consequences it produces. - If the consequence is positive we continue the
behaviour, if it is negative we are likely to
decrease the behaviour. - In order to learn these behaviours we are
practicing trial and error learning.
114TRIAL AND ERROR LEARNING
- Trial and error learning describes an organisms
attempts to learn, or to solve a problem, by
trying alternate possibilities until a correct
solution or desired outcome is achieved. - It involves a number of attempts (trials) and a
number of incorrect choices (errors) before the
correct behaviour is learned. - Once learned, the behaviour will usually be
performed quickly and with few errors.
115TRIAL AND ERROR LEARNING
- Trial and error learning involves motivation,
exploration, incorrect and correct responses, and
reward. - Receiving a reward of some kind leads to the
repeated performance of the correct responses,
strengthening the association between the
behaviour and its outcome.
116The number maze and the learning curve
- Negotiate the maze by drawing a line between each
consecutive number starting at number 1. - You will be given a 1 minute interval for each
maze. - Repeat the procedure for each maze.
- Record the number you reached in each maze in the
time allowed. - Plot a graph of these numbers showing your
improvement throughout the trials.
117The number maze and the learning curve
- What is the shape of the graph?
- Is this what you would expect to see? Why?
- What was the reinforcement that caused learning
to occur in this case?
118THORNDIKES EXPERIMENT WITH CATS.
- In the early years of the twentieth century,
about the same time Pavlov was investigating the
digestive system of dogs, Edward Thorndike was
performing experiments that would form the basis
of operant conditioning. - In Thorndikes puzzle box experiment, he would
place a cat inside a puzzle box and put a fish
outside the box. The idea was to observe and time
the cats attempts to escape the box and get to
the fish.
119- At first the cat showed a wide range of random
behaviours in attempting to escape the box, until
it accidentally stepped on a leaver in the middle
of the box which released the door. - The cats behaviour gradually became less random.
- Each time it was put in the box the cat would
escape a little more quickly, until eventually it
escaped as soon as it was put back in the box. - Because the cat had started with random behaviour
and had gradually learned the solution to the
puzzle box, Thorndike believed that learning was
a trial and error process.
120- Thorndike found that the animal learned those
behaviours that were followed by pleasant
consequences, while other behaviours were not
repeated. This became known as the law of effect.
- The law of effect suggests that behaviours that
lead to positive consequences are repeated and
behaviours that do not lead to positive
consequences are not repeated. - The conditioning process became known as
instrumental conditioning, because behaviour is
instrumental in obtaining rewards.
121- Although it was formulated to explain
goal-directed behaviour, operant conditioning
attempts to explain such behaviour in terms of
what has happened in the past.
122OPERANT CONDITIONING
123OPERANT CONDITIONING
- The term operant conditioning was not
introduced until years after Thorndikes
experiments with cats. - This term was coined by a man named Burrhus
Skinner. - He suggested that an operant is a response (or
set of responses) that occurs and acts on the
environment to produce some kind of effect.
124- Essentially an operant is a response of behaviour
that generates consequences. - Before conditioning, an organism might make many
operant responses. (The cat clawing and biting). - Operant conditioning is based on the principle
that an organism will tend to repeat behaviours
that have desirable consequences, or that will
enable it to avoid undesirable consequences. - Furthermore, organisms will tend not to repeat
behaviours which have undesirable consequences.
125Three-phase model of operant conditioning
- The theory of operant conditioning has been
expressed as a three-phase model based on
Thorndikes law of effect. - The three-phase model of operant conditioning
(S-R-C) has three components 1) the stimulus (S)
that precedes the operant response, 2) the
operant response (R) the response to the stimulus
and 3) the consequence (C).
126- The can be described as stimulusgtresponsegtconseque
nce.
Stimulus (S) Operant response (R) Consequence (C)
Definition The action that can have an effect on the environment The event that follows the operant response
Examples Puzzle box
Soft-drink vending machine
127SKINNERS EXPERIMENTS WITH RATS
- In order to study operant conditioning Skinner
wanted to test how behaviour can be explained by
the relationships between the behaviour, its
antecedents (the events that come before it), and
its consequences. - To do this he created an apparatus called the
Skinner Box.
128SKINNERS EXPERIMENTS WITH RATS
- A Skinner Box is a small chamber in which an
experimental animal learns to make a particular
response for which the consequences can be
controlled by the researcher. - It has a leaver which delivers a reward (food)
when pushed.
129- Some boxes have lights, buzzers and grid floors
which provide mild electric shocks. - The lever is also attached to a cumulative
recorder which tracks the desired responses,
their frequency and speed. - Rats and pigeons were used for these experiments.
- Skinner 1938, classic experiment to demonstrate
operant conditioning.
130- When a hungry rat was placed in the box, it would
scurry around, randomly touching the floor and
walls. - Eventually it would accidentally press the leaver
on the wall in which case a pellet of rat food
would drop into the food dish and the rat would
eat it. - With additional repetitions of leaver pressing
followed by food, the rats random movements
began to disappear and were replaced by more
consistent lever pressing.
131- Eventually the rat was pressing the lever as fast
as it could eat the pellets. - The pellet was a reward for making the correct
response. - Skinner referred to different kinds of rewards as
reinforcers. - Skinner wanted to demonstrate the impact of
reinforcement according to different types of
schedules of reinforcement. Eg. Every time a
correct response is made compared with every
second time the response is made.
132- Thorndikes cats could see their reinforcement
from the box they were placed in, so although it
took them many trials to make the correct
response, their motivation was clear. - Skinners lab animals came across their
reinforcement by chance. - Skinner had to use hungry rats in order for them
to act erratically and hit the leaver by chance.
133ELEMENTS OF OPERANT CONDITIONING
- Central to operant conditioning is reinforcement
because learning through operant conditioning
occurs as a result of consequences of behaviour. - A response that is rewarded is strengthened,
whereas one that is punished is weakened. - Reinforcement and punishment can be delivered in
a number of ways.
134REINFORCEMENT
- How do you train a dog?
- How do you ensure that you dont get wet when
walking in the rain? - Reinforcement may involve receiving a pleasant
stimulus (pat/food) or escaping an unpleasant
stimulus (rain). - In either case the outcome is one that is desired
by the organism performing the behaviour.
135- Reinforcement is applying a positive stimulus or
removing a negative stimulus to subsequently
strengthen or increase the likelihood of a
particular response that it follows. - A reinforcer is a stimulus that strengthens or
increases the frequency or likelihood of a
response occurring and being repeated. - The term reinforcer is often used
interchangeably with the term reward. - The only difference is that reward suggests an
outcome that is positive, such as satisfaction or
pleasure. - A stimulus is a reinforcer if it strengthens the
preceding behaviour.
136SCHEDULES OF REINFORCEMENT.
- The way reinforcement is delivered is referred to
as a schedule of reinforcement. - A schedule of reinforcement is a program for
giving reinforcement, in terms of how frequently
it is given and the way the response is
reinforced. - Reinforcement may be provided on a continuous
schedule (after every correct response) or on a
partial reinforcement schedule (that is only on
some occasions). - The difference between the two is the speed with
which the response is conditioned and the
strength of the conditioned response.
137- In the early stages of conditioning, learning is
most rapid if the correct response is reinforced
every time it occurs. - This is known as continuous reinforcement.
- Once a correct response consistently occurs, a
different reinforcement schedule can be used to
maintain, increase or strengthen the response. - Responses maintained through a program of
intermittent reinforcement are stronger and are
less likely to weaken or cease than those
maintained by continuous reinforcement.
138- Partial reinforcement is the process of
reinforcing some correct responses but not all of
them. - Reinforcement can be given after a certain number
of correct responses have been made (ratio) or as
a certain amount of time has passed (interval).
139- Reinforcement may be given on a regular basis
(fixed) or it may be unpredictable (variable). - Behaviour that is conditioned on a schedule of
partial reinforcement is generally the most
difficult to change. - Each schedule produces a different effect on the
rate and pattern of a response.
140- Partial reinforcement can be given in one of four
patterns - Fixed ratio
- Variable ratio
- Fixed interval
- Variable interval
141Fixed ratio
- A set number of correct responses must be made
before obtaining reinforcement for example, a
newspaper delivery person is paid 5 for every
100 papers delivered. - This produces a very high response rate.
142Variable ratio
- A varied number of correct responses must be made
before receiving reinforcement when playing a
poker machine, players keep playing even though
they do not know how many dollars they will have
to put in before receiving reinforcement. - This also produces a very strong response rate.
- This is less predicable which effects extinction.
143Fixed interval
- After a correct response is made, a reinforcer is
given after a fixed amount of time has passed
you press the button at the traffic lights to
cross but the signal only changes after a certain
amount of time has passed. - This schedule produces moderate response rates
with spurts of activity mixed with inactivity.
144Variable interval
- A reinforcer is only given for the first correct
response after a varied amount of time when you
go fishing you continue to throw your line in the
water not knowing how long it will take for the
fish to bite. - This produces a slow steady rate of response and
tremendous resistance to extinction.
145- In general, ratio schedules tend to produce more
rapid responding than interval schedules.
146POSITIVE REINFORCEMENT
- A positive reinforcer is a stimulus that
strengthens or increases the likelihood of a
desired response by providing a satisfying
consequence (reward). - Positive reinforcement occurs from giving or
applying a positive reinforcer after the desired
response has been made. - The food pellet in the Skinner box.
- Receiving a good mark if you have studied hard.
147NEGATIVE REINFORCEMENT
- A negative reinforcer is any unpleasant or
aversive stimulus, that when removed or avoided,
strengthens or increases the likelihood of a
desired response. - Skinner Box and electric current.
- Negative reinforcement is the removal or
avoidance of an unpleasant stimulus. It has the
effect of increasing the likelihood of a response
being repeated.
148- The important distinction between positive and
negative reinforcement is that positive
reinforcers are given and negative reinforcers
are removed or avoided. - Both procedures lead to desirable consequences.
- Examples of negative reinforcers are
- -turning off a scary video
- -driving slowly to avoid a speeding fine
149- If you take a panadol when you have a headache
and the headache goes away, the behaviour of
taking the panadol has been negatively
reinforced, and it is likely you will repeat that
behaviour next time you have a headache. - TO REMEMBER
- -positive () reinforcer adding something
pleasant - -negative (-) reinforcer subtracting something
unpleasant (which results in a pleasant or
desirable outcome.
150PUNISHMENT
- Punishment is the delivery of an unpleasant
stimulus following a response, or the removal of
a pleasant stimulus following a response. - It has the same unpleasant quality as a negative
reinforcer, but unlike a negative reinforcer, the
punishment is given or applied, whereas the
negative reinforcer is prevented or avoided. - Punishment is designed to weaken a response, or
decrease the probability of that response
occurring again over time.
151- The distinction between negative reinforcement
and punishment is that negative reinforcement
encourages a response whereas punishment
discourages it.
152- Lets say that your bedroom is next to your
brother or sisters and they like to play really
loud music. You pound on the wall and the volume
of the music decreases. This is negative
reinforcement as the next time the music is too
loud you will again pound on the wall and expect
the same response. If your brother or sister
turns the music up louder or comes in and yells
at you (punishment) you are less likely to pound
on the wall next time!!
153Response cost
- It is also punishing to take away something that
an individual perceives to be positive such as
privileges or money. - Punishment also occurs when a reinforcer or
positive state of affairs is removed. - This is call response cost.
- Response cost is when a reinforcer or something
positive is removed following a response, and
this decreases the likelihood that this response
will occur again.
154Factors that influence the effectiveness of
reinforcement and punishment.
- Reinforcement is intended to increase the
likelihood of a behaviour being repeated and
punishment is intended to decrease the likelihood
of behaviour being repeated. - -Order of presentation
- -Timing
- -Appropriateness
155ORDER OF PRESENTATION
- To use reinforcement and punishment effectively
it is important that it is presented after a
desired response, never before. - Learning consequences of certain responses.
156TIMING
- Reinforcement are most effective when they are
given immediately after the response has
occurred. - This helps the organism to make the association
between the response and the reinforcer/punishment
. - If there is a delay learning will take longer.
- Sometimes, in real life, it is not possible for
consequences to be given immediately.
157APPROPRIATENESS
- For any stimulus to be a reinforcer, it must be
pleasing or satisfying in some way. - It is not known if something is going to be a
reinforcer until after it has been used. - It cannot be assumed that a reinforcer that works
in one situation will work in other situations. - Characteristics of the individual need to be
taken into account.
158- A stimulus must be appropriate as a punishment,
as in it must provide a consequence that is
unpleasant, and therefore likely to decrease the
unwanted behaviour.
159KEY PROCESSES IN OPERANT CONDITIONING
- The same key processes are involved in both
classical and operant conditioning, however the
way in which these processes occur is slightly
different in each. - -Acquisition
- -Extinction
- -Stimulus generalisation
- -Stimulus discrimination
- -Spontaneous recovery
160ACQUISITION
- Acquisition refers to the overall learning
process, during which a specific response, or set
of responses is established. - The types of behaviours acquired during operant
conditioning in comparison to classical
conditioning are generally more complex. - In operant conditioning, acquisition is the
establishment of a response through
reinforcement.
161- Some behaviours that are operantly conditioned
are too complex to be performed completely in the
beginning of the acquisition process. - Instead behaviours that are a simpler version of
the desired behaviour, or a step towards the
desired behaviour are rewarded instead. - This is known as shaping.
162EXTINCTION
- In operant conditioning, extinction may also
occur, and the process is similar to its
occurrence in classical conditioning. - Extinction is the gradual decrease in the
strength or rate of a conditioned response
following consistent non-reinforcement of the
response . - Extinction is less likely to occur when partial
reinforcement is used.
163SPONTANEOUS RECOVERY
- After the apparent extinction of a response,
spontaneous recovery can occur and the organism
will once again show the response in the absence
of any reinforcement. - The response is likely to be weaker.
- A spontaneously recovered response is often
stronger when it occurs after a lengthy period
followin