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LEARNING

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LEARNING MECHANISMS OF LEARNING Results Consequences (or lack of consequences) for the adult model did make a difference to the behaviour displayed by the children. – PowerPoint PPT presentation

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Title: LEARNING


1
LEARNING
MECHANISMS OF LEARNING
2
DEFINING 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.

3
Learning 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.

4
Learning 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.

5
Learning 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.

6
Learning 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.

7
BEHAVIOUR 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?

8
BEHAVIOUR NOT DEPENDENT ON LEARNING
  • Reflexes
  • Fixed-action patterns
  • Maturation

9
REFLEX 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.

11
FIXED-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.

14
Examples
  • Courtship of a Teminck Tragopan
  • The mating dance- A must see!!!!
  • Blue footed booby mating dance.

15
BEHAVIOUR 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.

16
Learned, 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

17
Learning curve experiment
  • Write operational hypothesis
  • Page 427

18
Learning 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.

20
Brain 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.

21
Brain structure Role in learning Effect of damage on ability to learn
The cerebellum
Hippocampus
Amygdala
Frontal lobes
22
The 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.

24
The 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.

25
The 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.

27
The 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.

28
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29
Phases 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.

30
Neuron 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.

32
Synapse 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

36
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37
Effects 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.

39
The 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.

42
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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.

45
Neurotransmitters
  • 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.

47
Plasticity 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

49
Developmental 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.

51
Adaptive 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.

56
Implications 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.

57
Timing 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.

61
Evidence 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.

64
Imaging 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.

66
THEORIES 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
  • CLASSICAL CONDITIONING

70
Ivan 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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  • 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.

76
Key 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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Classical 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.

80
BEFORE 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.
81
KEY PROCESSES IN CLASSICAL CONDITIONING
  • The key processes in classical conditioning are
  • Acquisition
  • Extinction
  • Stimulus generalisation
  • Stimulus discrimination
  • Spontaneous recovery

82
ACQUISITION
  • 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.

84
EXTINCTION
  • 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.

85
SPONTANEOUS 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.

87
STIMULUS 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).

89
STIMULUS 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.

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CLASSICAL 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.

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  • 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

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  • 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.

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  • 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.

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ETHICAL 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.

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  • 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.

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  • 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.

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  • 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.

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  • 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.

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  • 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.

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APPLICATIONS 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

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Graduated 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.

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  • 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.

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Most 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
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  • 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.

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Flooding
  • 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.

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  • 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.

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AVERSION 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.

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  • 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.

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  • 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

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  • 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.

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TRIAL AND ERROR LEARNING
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TRIAL 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.

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  • 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.

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TRIAL 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.

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TRIAL 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.

116
The 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.

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The number maze and the learning curve
  1. What is the shape of the graph?
  2. Is this what you would expect to see? Why?
  3. What was the reinforcement that caused learning
    to occur in this case?

118
THORNDIKES 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.

122
OPERANT CONDITIONING
123
OPERANT 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.

125
Three-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
127
SKINNERS 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.

128
SKINNERS 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.

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  • 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.

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  • 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.

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ELEMENTS 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.

134
REINFORCEMENT
  • 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.

136
SCHEDULES 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

141
Fixed 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.

142
Variable 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.

143
Fixed 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.

144
Variable 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.

146
POSITIVE 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.

147
NEGATIVE 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.

150
PUNISHMENT
  • 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!!

153
Response 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.

154
Factors 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

155
ORDER 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.

156
TIMING
  • 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.

157
APPROPRIATENESS
  • 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.

159
KEY 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

160
ACQUISITION
  • 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.

162
EXTINCTION
  • 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.

163
SPONTANEOUS 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
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