Transcript The behaviourist approach

The behaviourist approach
Access to HE Psychology
Learning outcome
Assessment criteria
1: Show knowledge
and understanding of
psychological theories
1.1: Identify key issues in named
psychological perspectives
1.2: Explain the main
characteristics of some
psychological theories
1.3: Discuss the relationship
between some key theories and
perspectives
4: Evaluate a range of
key theories and
perspectives in an
assignment
4.1: Show evidence in an
assignment of the evaluation of
theories and perspectives
Assessment
criteria
By the end of this lesson you will be
able to: -
1.3
Outline the assumptions of the
behaviourist approach
1.2
Explain classical conditioning
Explain of operant conditioning
4.1
Evaluate the behaviourist
perspective
Getting you thinking
How might you train a
dog to fetch a lead?
How might you stop a
bad habit such as biting
nails?
Key assumptions
• Our behaviour is shaped by the environment we live
in
• Behaviour is a response to something in the
environment (stimulus)
• It’s unscientific to speculate about ‘internal
processes’. Only ‘observable’ behaviour should be
studied because it can be easily measured
• Behaviour is shaped via classical and operant
conditioning
Watson
“Give me a dozen healthy
infants, well formed, and
my own specified world to
bring them up in and I’ll
guarantee to take any one
at random and train him
to become any type of
specialist that I might
select – a doctor, lawyer,
artist”
(Watson, 1925 cited in Gross, 2009:p69
• The behaviourist approach suggests two main
processes whereby people learn from their
environment through the principles of
conditioning
–Classical conditioning: learning by
association
–Operant conditioning: learning from the
consequences of behaviour.
Classical Conditioning
• A procedure during which an animal or person
learns to associate a reflex response with a
new stimulus
• Watch the video of Pavlov’s experiment, and then
answer the following questions:
– What was the original aim of Pavlov’s experiment?
– The dogs in Pavlov’s experiment would salivate on
hearing his footsteps as he approached. How did Pavlov
explain this reaction?
– http://www.youtube.com/watch?v=hhqumfpxuzI&p=7F7C4D28F621654
B&playnext=1&index=1
Classical Conditioning
• Pavlov was initially interested in the dogs’
digestion and salutatory glands
• Pavlov suggested that dogs were associating
the footsteps with the food because the two
‘things’ (the stimuli) had occurred together so
many times.
Classical Conditioning
• Pavlov then decided to further his research and
give the dogs food at the same time as ringing a
bell (a neutral stimulus).
• Results showed that after several pairings, the
dog salivated to the bell, even without the
presence of food.
• The dogs associated the bell with food.
• Pavlov gave parts of his procedures particular
names
– Unconditioned: This refers to something
that is unlearned
– Conditioned: When something has been
learned
• Classical conditioning can be described as
‘learning by association’. The dogs in Pavlov’s
experiment learnt to associate the ringing of
the bell with food.
Exercise
• Complete this classical conditioning schedule
on the handout provided
Before conditioning Food
trial begin – an
(UCS)
unconditioned reflex
During conditioning
trials
Bell
(NS)
After conditioning
Bell
(CS)
Salivation
(UCR)
+
food Salivation
(UCS) (UCR)
Salivation
(CR)
Extinction
• Pavlov was also interested in how long this
learning would last.
• If he continued to ring the bell without giving
the dog any food, after a while the dog would
no longer salivate.
• A conditioned response which dies out is
known as extinction.
Spontaneous recovery
• However, Pavlov found that after a period of
rest (of not ringing the bell), if he suddenly
rang the bell the dog would immediately
salivate again. He referred to this as
spontaneous recovery.
Generalisation
• Pavlov also found that, even if he changed the
tone of the bell, the dog would still salivate.
• He referred to this as generalisation because
the animal was widening its learned response
to a similar conditioned stimulus (a new bell
sound).
Discrimination
• However, Pavlov worked out how to stop
generalisations. He rang a number of bells of
different tones, but only presented food when a
particular bell was rung.
• The dog did not salivate at hearing the other bells
ring, and only salivated at the bell that had been
paired with food.
• Pavlov referred to this as discrimination because
the dog had learnt to narrow its response to a
particular stimulus.
Poor little Albert… Watson and Raynor (1920)
At 9 months, Albert showed no fear
of animals e.g. (rats, dogs and
rabbits).
Question: what is the
unconditional response in
this experiment?
Answer: Albert’s response to
the loud noise made by the
hammer.
Question: What is the
conditioned response?
Answer: Albert’s fear of the rat
At 11 months, Albert was shown a
white rat. A few second later, a
hammer was struck against a steel
bar which startled Albert. This
experiment was repeated several
times.
After a while, the rat alone induced
fear within the child, who would cry
and crawl away from the rat.
http://www.youtube.com/watch?v=9hBfnXACsOI&feature=related
Operant conditioning
• Learning through reinforcement.
• If behaviour is positively reinforced, it should
be repeated.
• If behaviour is punished, it should become
extinct.
Activity
• List some of the things parents/teachers could do to
encourage children to: – Tidy their bedrooms
– Help with the washing up
– Complete home work on time
BF Skinner
• Operant conditioning simply means changing
behaviour by reinforcement: • Positive reinforcement: Behaviour is reinforced by
rewards. E.g. The rat is rewarded food after pressing a
lever.
• Negative reinforcement: Strengthening behaviour by
removing an unpleasant experience. E.g. electric
current, which causes the rat some discomfort, is
removed when the rat presses a lever.
• Watch this clip from the big bang theory
• How is the young woman’s behaviour being
shaped?
• http://www.youtube.com/watch?v=euINCrDbbD4
B.F Skinner: Operant Conditioning
Skinner Box
http://www.youtube.com/watch?v=PQtDTd
Dr8vs&feature=related
http://www.youtube.com/watch?v=rTND_H
GrP08&feature=related
• Punishment differs from reinforcement
because it does not encourage a desired
behaviour; it just stops that unwanted
behaviour.
• For example, we can punish a child, who has
been drawing on a wall, by taking away its
colouring pens.
Behaviour shaping
• Reinforcement can also be used to teach
complex behaviours in animals. This is called
behaviour shaping, and involves changing
behaviour by breaking down a task into small
steps.
• Skinner taught pigeons how to play ping pong
using this technique.
Behaviour shaping: Ping-pong pigeons
• Skinner taught pigeons how to play ping pong
using this technique. A pigeon will learn to
play ping pong through a series of steps: – Moving towards the ball
– Touching the ball with its beak
– Hitting the ball with its beak
– Hitting the ball towards another pigeon
• The trainer will reinforce each of these steps
by rewarding the pigeon with grain
http://www.youtube.com/watch?v=vGazyH6fQQ4
http://www.youtube.com/watch?v=I_ctJqjlrHA&feature=related
Pair activity
• Describe how behaviour shaping could be
used to train a dog to fetch its lead. You will
need to decided on each step of the whole
procedure and the reward you will use.
• Can you think of any human behaviours that
are or could be shaped by ‘behaviour shaping?
Positive reinforcement, negative reinforcement
or punishment?
• A rat receives an electric shock to his brain,
which creates pleasure every time he presses
a bar. Before long, the rat is pressing the bar
fifty times.
– Positive reinforcement
Positive reinforcement, negative reinforcement
or punishment?
• Fred refuses to take out the rubbish so his
mother refuses to allow him to watch his
favourite TV show.
– Punishment
Positive reinforcement, negative reinforcement
or punishment?
• Andrew is upset because every time he goes
to school he is bullied. Andrew’s mother has
noticed he complains he feels sick every
morning and asks to stay home from school.
His mother usually agrees.
– Negative reinforcement
Positive reinforcement, negative reinforcement
or punishment?
• Tim is learning to play the trombone. His
parents say that each time he successfully
learns a new piece he can have some money.
– Positive reinforcement
Positive reinforcement, negative reinforcement
or punishment?
• When a horn sounds hamsters jump on the
wheel in their cages and begin running. They
know that if they don’t jump on the wheel, a
blast of cold air will blow.
– Negative reinforcement
Evaluating the behaviourist approach
• Using the following points, evaluate the
behaviourist perspective: – What might be the advantages of laboratory experiments
– What might be the practical applications of classical and
operant conditioning?
– Reductionism Are complex ideas reduced to their component
parts?
– Ecological Validity Can the findings be applied to real life
settings?
– Extrapolation Does data from non-humans help understand
humans?
Strengths
1. Behaviourism has been very influential:
Modern psychology still relies heavily on
scientific methods that were first proposed by
Watson’s (1913) Behaviourist Manifesto.
2. Practical applications: Behaviourism has given
rise to numerous therapeutic applications. For
example:
•
token economies
•
aversion therapy
Weaknesses
•
The approach is seen as mechanistic. Human beings are
complex animals, we feel emotions, we live in complex
societies etc. To see humans as functioning in a mechanistic
manner is to over-simplify human behaviour.
•
It excludes innate factors. We now know that genetic factors
do play an enormous role in influencing human behaviour and
behaviourism simply does not acknowledge this.
•
It is deterministic and reductionist. The approach rejects the
notion of free will, that we actively choose how to behave.
Reductionist means that the approach takes complex
behaviours and tries to explain them in simplistic ways (e.g. in
terms of S-R units).
•
Based on work with non-human animals. The approach has
been criticized for making generalizations about human beings
based on experiments on non-human animals