Download Clark Leonard Hull

Clark Leonard Hull
Hull
Background
• Born 1884 in Akron NY
• Graduated U. of Michigan in
1913
• Ph.D. U. of Wisconsin 1918
• 1929-1952 Professor of
Psychology at Yale
• Died 1952
• Developed HypotheticoDeductive System
Clark Hull
•
•
•
•
•
•
•
•
•
•
•
SER
= Reaction potential
SHR = habit strength
D = Drive
IR = reactive inhibition
SIR = conditioned inhibition
SOR = oscillation effect
SLR = Threshold
StR = reaction time
p = response probability
n = trials to extinction
A = response amplitute
Clark Hull
Postulate 1 & 2
• Sensing the External
Environment and the Stimulus
Trace
– Stimulus Trace S-s-R
• The Interaction of Sensory
Impulses = 
Clark Hull
S1
s1
S2
s2
S3
s3
S4
s4
S5
s5
s
r
R
Clark Hull
Postulate 3
• Unlearned Behavior - an need
arises an the individual has a
hierarchy of responses patterns
to take care of this need. These
response patterns are innate and
if the first response pattern
doesn’t work then we go to the
second.
Clark Hull
Postulate 4
• Contiguity and Drive Reduction
as Necessary Conditions for
Learning
– If a stimulus leads to a response
and its satisfies a biological need
(drive reduction) the S-R bond is
strengthened.
– The more often leads to a need
satisfaction the stronger the bond
(Habit Strength SHR)
– Habit Strength or SHR = 1 - 100.0305N
Clark Hull
Postulate 5
• Stimulus Generalization - a
stimulus will elicit a
conditioned response depending
on how similar the stimulus is
to the stimulus that was used
during training (stimulus
generalization)
• SHR = generalized habit
strength - transfer of training
Clark Hull
Postulate 6
• Stimuli Associated with Drives
- Primary motivation (D), at
least that resulting from food
deprivation, consists of
multiplicative components: (1)
the drive proper (D’) which is
an increasing monotonic
sigmoid function of h, the
number of hours of food
deprivation; and (2) a negative
or inanition component ()
which is positively
Clark Hull
Postulate 6
• accelerated montonic function
of h decreasing from 1.0 to zero
– D = D’ x 
– where
• D’ = 37.824 x 10-27.496*1/h+4.001
•  = 1 - .0000045h2.486
Clark Hull
Postulate 6
300
250
200
150
100
50
0
Clark Hull
Postulate 7
• Reaction Potential as a Function
of Drive and Habit Strength The likelihood of a learned
response being made at any
given moment is called reaction
potential (SER)
• SER = SHR x D
Clark Hull
Postulate 8
• Responding Causes Fatigue,
Which Operates Against the
Elicitation of a Conditioned
Response
– Reactive inhibition (IR)
– reminiscence effect - stop
studying prior to test
– massed vs. distributed practice
Clark Hull
Postulate 9
• The Learned Response of Not
Responding - fatigue is a
negative drive state.
– Conditioned Inhibition (SIR)
• Effective reaction potential =
ER = SHR x D - (IR + SIR)
Clark Hull
Postulate 10
• Factors Tending to Inhibit a
Learned Response Change from
Moment to Moment - there is an
“inhibitory potentiality” which
varies from moment to moment
and operates against the
elicitation of a response
– Oscillation effect (SOR)
– This is a wild card in Hull’s
theory
Clark Hull
Postulate 10
•
.
• Momentary Effective Reaction Formation
= SE R
– Momentary Effective Reaction Potential
.
SER = SHR x D - (IR + SIR) - SOR
Clark Hull
Postulate 11
• Momentary Effective Reaction
Potential Must Exceed a Certain
Value Before a Learned
Response Can Occur
.
– The value of SER must exceed the
reaction threshold (SLR)
Clark Hull
Postulate 12
• The Probability that a Learned
Response Will Be Made Is a
Combined Function of SER, SOR,
and SLR
– In the beginning of training the
momentary reaction potential will
be close to the threshold therefore
the oscillation effect will play a
role. As training goes on the
oscillation effect will play less of
a role.
Clark Hull
Postulate 13 & 14
• The greater the Value of the
Effective Momentary Reaction
Potential the Shorter will be the
Latency Between S and R
– Latency = (StR)
• The value of the Effective
Momentary Reaction Potential
will Determine Resistance to
Extinction
Clark Hull
Postulate 15 & 16
• The Amplitude of a Conditioned
Response Varies Directly with
the Effective Momentary
Reaction Potential
• When Two or More
Incompatible Responses Tend to
Be Elicited in the Same
Situation, the One with the
Greatest Effective Momentary
Reaction Potential will Occur
Clark Hull
Changes - 1952
• Performance is altered as a
result of the size of the
reinforcement, therefore Hull
included incentive as a factor
(K)
– Crespi Effect - a rapid change in
performance as a result of a
change in the size of the
reinforcement
Clark Hull
stimulus-intensity
• Stimulus Intensity Dynamism
– the greater the intensity of a
sitmlus, the greater the probability
that a learned response will be
elicited
.
SE R
= [ SHR x D x V x K- (IR + SIR)] - SOR
• Instead of drive reduction Hull
decided that it should be drive
stimulus reduction SD
– Actual Drive does not leave for a while
Clark Hull
rG
• Fractional Antedating Goal
Response rG
• This is Hull’s “mental”
component
• rG ) - this concept involves both
operant and classical
conditioning.
• A rat runs a T maze, no food is
in the left wing and food is in
the right wing. The rat will
soon learn to go to the right
Clark Hull
rG
• Turning the corner (since it
always comes just prior to the
reinforcement of food) becomes
a secondary reinforcer.
• But, it also becomes a
conditioned stimulus for
salivation
• The corner therefore acts both
as a conditioned stimulus and a
secondary reinforcement.
Clark Hull
rG
• Since the corner is a cs
salivation follows, but the
salivation becomes a secondary
reinforcement as well since it is
always followed by food.
• Likewise one could say that a
variety of internal stimului
(kinesthetic receptors) result in
muscle twitches etc becoming
secondary reinforcers, and keep
the animal moving forward
Clark Hull
rG
SD1
R1
SD2
R2
rG-sG
SD3
R3
rG-sG
R4
rG-sG
Clark Hull
Habit Family Hierarchy
• The habit family hierarchy
simply refers to the fact that in
any learning situation, any
number of responses are
possible and the one that is most
likely is the one that brings
about reinforcement most
rapidly and with the least
amount of effort.
– If one way is blocked we try
another
Clark Hull
Habit Family Hierarchy
SD1
SD2
R1
rG-sG
R2
R3
SD3
R1
R1
rG-sG
R2
R3
rG-sG
R2
R3
Mowrer
• Mowrer went through a series
of transitions in his theory.
– Two factor theory - worked with
avoidance conditioning
– Animal learns to avoid a shock
because a bell sounds and warns
the animal of the shock. The
anima must perform a behavior to
avoid the shock.
Mowrer
– Sign learning - bell which tells
animal to avoid the shock acts as
a “sign” or warning. Thus
Mowrer referred to it as “sign
learning”
– Once the animal is warned of the
shock it must perform a behavior
to avoid the shock thus this is
operant conditioning that Mowrer
called “solution learning”
Mowrer
– Mowrer went on to note that
many emotions can be explained
with the two factor theory
• Decremental Learning is a stimulus
that reduces a drive reduction like
eating vs. Incremental Learning
where a stimulus increases a drive
like shock
• One can experience the emotion of
hope if a bell sounds just prior to
food or of disappointment if the bell
sounds just prior to the removal of
food
Mowrer
• Eventually Mowrer considered
all learning “sign learning”.
– Mowrer felt that even
proprioceptive stimuli come to
give a sign of what to expect and
there was not the need for
solution learning.
Kenneth Spence
• Spence believed in latent
learning - no reinforcement is
necessary in order to learn.
– Supported Aristotles law of
contiguity
– Supported Aristotles law of
frequency
• Incentive Motivation - Spence
strongly believed in (K)
Incentive Motivation
– K was the energizer of learned
behavior
Kenneth Spence
– He believed that rG-sG
– Spence therefore had the
momentary effective reaction
potential equal to:
(D + K) x SHR - IN
– Spence felt that an organism will
make a response even if there is
no reinforcement for doing so
Kenneth Spence
• Extinction - frustration
competition theory of extinction
– extinction does not occur because
of fatigue as Hull suggests but
rather because frustration of not
receiving a reinforcer competes
with the reinforcer. Spence felt
that we have a primary frustration
when we do not receive
reinforcement and like a
fractional antedating goal
response we build a fractional
antedating frustration response.
Abram Amsel
• Examined Spence’s idea that
frustration causes extinction
– Amsel and Roussel showed that
animal increases responding
before decreasing responding
during extinction frustration
effect
– Bower showed that the larger the
reinforcer the faster the
extinction, assumably from
frustration.
Abram Amsel
• Analyzed partial reinforcement
effect - (extinction is slower
when organism is being
reinforced with a partial
reinforcement)
• Developed fractional antedating
frustration response
Neal Miller
• Visceral Conditioning and
Biofeedback