Chapter 5 Powerpoint 1

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Ch 5 learning
How the environment influences our behavior.
learning
 More than just picking up knowledge or a skill:
 A semi-permanent change in behavior brought by
experience or practice
The four pillars of
learning
 Classical Conditioning – gaining automatic connections
 Operant Conditioning – repeating what works, avoiding what
doesn’t
 Social Learning – being influenced by those we admire
Classical Conditioning
 Learning to make an involuntary (reflex) respond to
a stimulus other than the original natural stimulus
 Reflex- involuntary response
 Unconditioned stimulus UCS- a naturally occurring
stimulus that leads to a reflex
 Unconditioned response UCR- an involuntary (reflex)
response to a naturally occurring or UCS
Classical Conditioning
 Neutral Stimulus NS- Stimulus that has no affect on the desired
response
 Conditioned Stimulus CS- Stimulus that becomes able to
produce a learned reflex response
 paired with the original unconditioned stimulus
 Conditioned Response CR-Learned reflex response to a
conditioned stimulus

background
 It all started with Ivan Pavlov and his study of the digestive
system
 Research based on work with animals
 Studied the automatic connection between food (meat) in the
mouth and the flow of digestive juices
 UCS (meat in mouth) > UCR (saliva)
The big idea
 Start with an unconditioned reflex – an automatic connection
between a stimulus and a response (meat>saliva)
Big idea part 2
 Develop new automatic responses by repetitively pairing an
originally neutral stimulus with an UCS
Let’s say that a
different way
 An air puff in the eye (UCS) will always
make us blink (UCR)
 Flashing a red card won’t
 But if we repetitively flash the red card,
shortly followed by the air puff, eventually,
 Just flashing the red card will make us
blink !
examples
 That particular corner at your high school
 The torturer’s black shoes
 The whistling of a V1 “shrieker”
 The song from that certain summer that reminds you of …..
 Smell of food your grandma made
 Stimulus Generalization
 Other stimuli that is similar can lead to the same response
 Stimulus Discrimination
 When a person/animal is able to learn to respond different
stimuli in different ways
Extinction and
Recovery
 When the response “Dies Out”
 Remove the reinforcement CS and the CR will weaken and
disappear
 Spontaneous Recovery
 The CR can briefly reappear when the original CS returns
 Will be weak and short lived
Unraveling the
connection
 In CC, extinction takes place when we repeatedly present
the CS without the UCS following it
More perspectives
 CC prepares us for significant events by identifying events
that commonly predict them
 Gives us advance warning of upcoming threats and
opportunities
 The more unfamiliar the CS or the more powerful the UCS
the faster the CR takes
Other aspects
 The process that establishes or strengthens a CR is
called acquisition
 A CS can even be a thought
All together now
 First we build the CS>CR connection
through acquisition,
 Then we unravel it through extinction,
 If we then stop presenting the CS for a
while, once we resume its use,
 The CR will return, but not for long, unless
it is again paired with the UCS
Extending the
connection
 The CR can occur even without presentation of the exact CS
which formed it, if the new CS is similar enough
 Stimulus generalization – the extension or broadening of a
CR from the original CS to another, similar stimulus
 The more similar the entire setting is, the more likely the
new connection will form
Narrowing
connections
 If differing stimuli, although quite similar to
the CS, are never, or rarely, followed by the
UCS, then the CR will not emerge
 Stimulus discrimination – differing
responses to differing stimuli that have been
followed by differing events
Is it just timing?
 The concept of blocking
 If a CS/CR link has been established, pairing a new CS will not
work no matter how hard you may try
 Conditioned taste aversion
The power of
prediction
 It’s reliability that counts, the CS’ ability to
accurately and consistently predict the UCS.
 The UCS must be more likely to occur after
the CS.
The big picture
 CC involves visceral reactions involving the
sympathetic nervous system – you feel it in
your gut.
 It prepares us for important challenges and
threats.
 But it does not tell us what to do.
The next step
 For how we learn voluntary, planned
behaviors, we turn to operant
conditioning.
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