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Chapter 5: Schedules of Reinforcement


A Schedule of Reinforcement is a prescription that states how and when ... pattern emerges, but once it does, the orderliness of behavior is remarkable. ... – PowerPoint PPT presentation

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Title: Chapter 5: Schedules of Reinforcement

Chapter 5 Schedules of Reinforcement
Schedules of Reinforcement
  • A Schedule of Reinforcement is a prescription
    that states how and when discriminative stimuli
    and behavioral consequences will be presented.
  • Schedules of reinforcement are common in everyday
    life. A rat pressing a lever for food and a
    person turning on a light seem to have little in
    common. Humans are very complex organisms They
    build cities, write books, go to college, go to
    war, conduct experiments, and do many other
    things that rats cannot do. Nonetheless,
    performance on schedules of reinforcement has
    been found to be remarkably similar for different
    organisms, many types of behavior, and a variety
    of reinforcers.

Importance of Schedules of Reinforcement
  • Rule for the presentation of stimuli that precede
    operants and the consequences that follow them
  • Schedules are the fundamental determinants of
  • Rate and temporal patterns of responding
  • Probability of responding

  • Partial reinforcement effect
  • Discrimination hypothesis
  • Generalization decrement hypothesis
  • Contingency of reinforcement - features defined
    by the schedule
  • Steady-state performance
  • Strained performance

Partial reinforcement effect Resistance to
extinction greater after partial reinforcement
than after continuous reinforcement   Theory Discr
imination hypothesis harder to detect change to
EXT after PRF than CRF, the subject cannot
discriminate that behavior its is on EXT.
Generalization decrement as EXT continues the
situation is more and more different than when
reinforcement was in effect. But the degree of
generalization is much greater from PRF to EXT
than from CRF to EXT. The reinforcement
contingencies in PRF and EXT are more similar
than in CRF and EXT.
Understanding Cumulative Records
  • Plots responses as they occur moment to moment
  • A pen records time horizontally. Each response
    moves the pen vertically
  • Reinforcers are marked
  • Slope of the record indicates response rate
  • Steep High
  • Flat Low

Time moves Response moves
low rate
No response
high rate
Schedules and Patterns of Response
  • Patterns of response develop on schedules of
    reinforcement. These patterns come about after
    an animal has experience with the contingency of
    reinforcement defined by a particular schedule.
  • Subjects are exposed to a schedule of
    reinforcement and, following an acquisition
    period, behavior typically settles into a
    consistent or steady-state performance.
  • It may take many experimental sessions before a
    particular pattern emerges, but once it does, the
    orderliness of behavior is remarkable.

Schedules and Patterns of Response
  • When organisms are reinforced for a fixed number
    of responses, a pause-and-run pattern of behavior
  • Responses required by the schedule are made
    rapidly and result in reinforcement.
  • Following each reinforcement, there is a pause in
    responding, then another quick burst of
  • This pattern repeats over and over and occurs
    even when the size of the schedule is changed. A
    pause-and-run pattern has been found for horses,
    chickens, vultures, and children.

Schedules of Reinforcement
  • CRF - continuous reinforcement FR 1
  • Fixed Ratio- FR an FR schedule
  • Postreinforcement pause
  • run of responses
  • Variable Ratio VR
  • Fixed Interval - FI scalloping
  • Long term - break and run
  • Humans
  • Variable Interval - VI

Reinforcement Schedules
  • Response based schedules
  • Fixed ratio FR
  • Variable ratio VR
  • Progressive ratio PR
  • Random ratio RR
  • Time Based Schedules
  • Fixed interval FI
  • Variable interval VI
  • Fixed and variable time FT/VT

Other Schedules
  • Differential reinforcement of low rates
  • IRT gt t
  • Differential reinforcement of high rates
  • IRT lt t

Behavior and Schedule Effects
  • Schedules of reinforcement affect operant
    behavior because the schedule may interact with
    other independent variables
  • When punished after every response during FR
    schedule, the pause length after reinforcement
  • Although once the animal emitted the first
    response, the rate to finish the run was
  • Punishment reduces the tendency to begin
    responding but once started the behavior is not

Behavior and Schedule Effects
  • Punishment has different effects when behavior is
    maintained on different schedules of
  • When on a VI (variable interval) and punished
    after each operant, the pattern of behavior is
    the same but the rate of response declines

Schedules of Positive Reinforcement
  • Continuous Reinforcement
  • Continuous reinforcement, or CRF, is the
    simplest schedule of reinforcement. On this
    schedule, every operant required by the
    contingency is reinforced.
  • CRF and Resistance to Extinction
  • Continuous reinforcement generates little
    resistance to extinction. Resistance to
    extinction is a measure of persistence when
    reinforcement is discontinued.

Reinforcement and Behavioral Momentum
  • Concept of momentum derives from a combination of
    response rate, as generated by schedules of
    reinforcement, and the behavioral dynamic of
    resistance to change, both of which are important
    dimensions of operant behavior and analogous to
    velocity and mass in physics
  • Behavioral Momentum refers to behavior persisting
    in the presence of a particular stimulus despite
    disruptive factors

Schedules of Positive Reinforcement
  • When compared to intermittent schedules,
    continuous reinforcement produces less resistance
    to extinction. This is called partial or
    intermittent reinforcement effect.

Response Stereotypy on CRF
  • When on CRF, the topography of response become
    very predictable and have very little
  • Rats were conditioned to poke their noses
    anywhere along a 50 cm slot on CRF schedule.The
    rats responded to the same point on the slot
    while on CRF
  • When placed on extinction, the variability of the
    placement along the slot increased.

Response Stereotypy on CRF
  • As continuous reinforcement persists less and
    less variation occurs of the operant class.
  • The variability of response may be inversely
    related to the rate of reinforcement.
  • Responses were stereotyped on CRF and became more
    variable when on intermittent or extinction
  • It appears that the general principle is when
    things no longer work try new ways of behaving.
  • Resurgence increase in topography variability
    during extinction, can contribute to the
    development of creative or original behavior

Ratio and Interval Schedules of Reinforcement
  • On intermittent schedules of reinforcement, some
    rather than all responses are reinforced.
  • Ratio schedules are response based that is,
    these schedules are set to deliver reinforcement
    following a number of responses.
  • Interval schedules pay off when one response is
    made after some amount of time has passed.
  • Interval schedules may be fixed or variable.
  • Fixed schedules set up reinforcement after a
    fixed number of responses, or a constant amount
    of time has passed. On variable schedules,
    response and time requirements may vary from one
    reinforcer to the next.

Ratio Schedules
  • A fixed ratio, or FR, schedule is programmed to
    deliver reinforcement after a fixed number of
    responses is made.
  • Continuous reinforcement is FR 1
  • FR schedules produce a rapid run of responses,
    followed by reinforcement, then a pause in
  • A cumulative record of behavior on fixed ratio
    looks somewhat like a set of stairs. There is a
    steep period of responding (the run), followed by
    reinforcement, and finally a flat portion. The
    flat part of the cumulative record is called the
    postreinforcement pause, or PRP.

Schedules of Reinforcement
  • Response-based only x responses are required
  • Fixed ratio reinforcer is delivered contingent
    on a set number of responses
  • FR 5 v FR 15
  • Direct contingency X responses must be emitted
  • The higher the FR, the higher the response rate
    (side effect) and the longer the pause
  • Side effect break and
  • run pattern
  • Ex piece rate

FR schedules produce pause-and-run
responding. Pauses occur just after
reinforcement, then responding becomes
steady. Pause length is a function of the
ratio. In what way?
Cumulative responses
Time -----gt
Analysis of Reinforcement Schedules
  • FR postreinforcement pause theories
  • Fatigue, a larger ratio produces a longer PRP as
    the subject catches its breath.But why not a
    PRP on VRs with large ratios?
  • Satiation, right after consuming reinforcement
    the subject is in a state of relative satiation.
    But PRPs happen after non-consumable reinforcers
  • Remaining response, on a multiple schedule, two
    or more schedules alternate each with its own SD
    and its own reinforcement. If a large ratio
    alternates with a shorter ratio, the PRP will be
    longest after the shorter ratio. A PRP might be
    called a PreRatio Pause

PRP in a Multiple Schedule
On a multiple schedule two or more basic
schedules alternate, each one w\ an SD and
primary reinforcement, as in a blue key light
FR50- SR-red key light-FR5-SR on a MULT schedule
such as this, the PRP is typically longer after
the FR5 than after the FR50. A PRP is more a
function of the upcoming ratio than the
ratio just completed.
Ratio Schedules
  • Variable-ratio, or VR, schedules are similar to
    FRs except that the number of responses required
    for reinforcement changes after each reinforcer
    is presented.
  • The average number of responses is used to define
    the schedule.
  • Ratio schedules produce a high rate of response.
  • When VR and FR schedules are compared, responding
    is typically faster on variable ratio. One
    reason for this is that pausing after
    reinforcement (PRP) is reduced or eliminated when
    the ratio contingency is changed from fixed to
    variable. The provides evidence that the PRP
    does not occur because the animal is consuming
    the reinforcer.

Ratio Schedules
  • Many contingencies set by games of chance are
    similar to variable-ratio schedules.
  • Gambling is often called addictive, but from a
    behavioral perspective it may be understood as
    persistent high-rate behavior generated by ratio
    contingencies of reinforcement.
  • A bird on a standard VR schedule may make
    thousands of responses for a few brief
    presentations of grain

  • Variable ratio a reinforcer is delivered after
    a varied and unpredictable number of responses
  • VR 30 means an average number of responses
  • Examples
  • Casting a line
  • Supposedly Gambling
  • Random ratio
  • Direct contingency mean number of responses
    must occur
  • Side effect constant, high rate of responding

Ratio Schedules
  • It is possible to set the average ratio
    requirements so high that an animal will spend
    all of its time working for a small amount of
  • Animal will show a net energy loss where effort
    expended exceeds caloric intake, similar to the
    self-defeating response sometimes seen in
    gambling behavior
  • Seemingly irrational behavior of gamblers is
    generated by an unfavorable probabilistic
    schedule of reinforcement

Interval Schedules
  • On fixed-interval (FI) schedules, an operant is
    reinforced after a fixed amount of time has
  • For example, on a fixed-interval 90-second
    schedule, one bar press after 90 seconds results
    in reinforcement.
  • When organisms are exposed to interval
    contingencies, they typically produce many more
    responses than the schedule requires.
  • Fixed-interval schedules produce a characteristic
    pattern of responding. There is a pause after
    reinforcement (PRP), then a few probe responses,
    followed by more and more rapid responding as the
    interval times out. This pattern of response is
    called scalloping.

Response-plus-time based schedules
  • Arrangement of reinforcer specifies time and
  • Fixed interval reinforcer is delivered after the
    first response occurs after a specific period of
  • FI 3 means the first response after three
    minutes elapses gets reinforced
  • Contingency one response after 3
  • Side effect scallop-shaped pattern
  • Little responding at beginning of interval
  • Lots of responding at end of interval
  • Ex Checking watch while waiting for a bus

FI schedules produce faster responding at the end
of the interval. Scallops appear in between.
Time -----gt
Interval Schedules
  • Following considerable experience with FI 5
    minutes, you may get very good at judging the
    time period.
  • In this case, you would wait out the interval and
    then emit a burst of responses. Perhaps you
    decide to pace back and forth during the session,
    and you find out that after 250 steps the
    interval has almost elapsed. This kind of
    mediating behavior may develop after experience
    with FI schedules.
  • Other animals behave in a similar way and
    occasionally produce a break-and-run pattern of

Generality of Schedule Effects
  • Behavior analysts assume that research on
    schedule effects with animals also apply to
  • The assumption of generality implies that the
    effects of reinforcement extend over species,
    reinforcement, and behavior.
  • Humans show similar performances to rats when
    placed on FI schedules.

Generality of Schedule Effects
  • The influence of language may explain why humans
    do not show characteristics of scalloping on FI
  • Humans either produce a high rate of response or
    a low rate of response.
  • People construct a verbal rule and behave
    according to the rule rather than the
    experimental contingencies.
  • Humans who have not developed language skills
    will respond to that of a rat and more like the
    characteristic effects of the schedule

Interval Schedules
  • On a variable-interval, VI, schedule responses
    are reinforced after a variable amount of time
    has passed.
  • For example, on a VI 30 second schedule, the time
    to each reinforcement changes but the average
    time is 30 seconds.
  • On this schedule rate of response is steady and
    moderate. The pause after reinforcement that
    occurs on FI usually does not appear in the
    variable-interval record. Because rate of
    response is moderate, VI performance is often
    used as a baseline for evaluating other
    independent variables.
  • VI contingencies are common in everyday life.

Schedules of Reinforcement
  • Generally, ratio schedules produce shorter IRTs
    and consequently higher rates of response than
    interval schedules.
  • Generally, it is well established that the
    postreinforcement pause is a function of the
    interreinforcement interval (IRI).

PostReinforcement Pause
  • PRP as a function of IRI
  • FI - ½ interval value.
  • FR pause increases as FR is increased, rate of
    response also increases.

  • VR and VI response rates
  • VR yoked VI
  • Rates are higher on VR schedules even when rate
    of reinforcement is the same
  • ?

  • VR and VI response rates
  • VR yoked VI
  • Rates are higher on VR schedules even when rate
    of reinforcement is the same
  • ?

VR VI maintain steady rates of responding FR
FI produce predictable post reinforcement
pauses Ratio schedules produce higher
response rates than interval schedules
Why? -         Feedback function Ratio
schedules selectively reinforce high response
rates because increased response rate means more
reinforcement. The faster the subject responds,
the sooner the next reinforcement is
obtained. Interval schedules preferentially
reinforce long Inter Response Times (IRTs)
because the longer you pause, the more likely the
first response after the pause will be
reinforced. Rate of responding is irrelevant to
obtaining the next reinforcement any sooner.
Variable schedules produce more consistent
responding (no pauses or scallops) than fixed
schedules. Why? VR schedules produce faster
response rates than VI. Why?
Rates of Response
Schedules and IRTs
FRs and VRs differentially reinforce short IRTS,
the shorter the time interval between consecutive
responses, the more frequent and rapid
reinforcement will be obtained. Ratio schedules
reinforce bursts of responding like a machine
gun. Interval schedules, whether fixed or
variable, tend to reinforce longer IRTS such as
respond-wait-respond-wait since responding faster
will not produce more frequent or rapid
reinforcement. On such schedules, only a single
response is required as long as that single
response occurs after the interval has elapsed.
As a result, a paced response rate with delays
between consecutive responses is likely to
produce reinforcement. These are molecular
accounts of response rate.
Rate of Response on Schedules
  • Dynamic interactions between
  • Molecular aspects - moment-to-moment
  • Molar aspects- length of session

Molecular Account of Rate of Response
  • The time between any two responses, or what is
    called the interresponse time (IRT) may be
    treated as an operant.
  • Generally, ratio schedules produce shorter IRTs
    and consequently higher rates of response than
    interval schedules.
  • To understand this, consider the definition of an
    operant class. It is a class of behavior that may
    either increase or decrease in frequency on the
    basis of contingencies of reinforcement. In other
    words, if it could be shown that the time between
    responses changes as a function of selective
    reinforcement, then the IRT is by definition an
    operant in its own right.

Molecular Account of Rate of Response
  • Several experiments have shown that the
    distribution of IRTs may in fact be changed by
    selectively reinforcing interresponse times of a
    particular duration.
  • When compared to ratio schedules, interval
    contingencies generate longer IRTs and
    consequently a lower rate of response.
  • Interval schedules may pay off after some amount
    of time has passed and a response is made. As
    IRTs become longer, more and more of the time
    requirement on the schedule elapses. This means
    that the probability of reinforcement for a
    response increases with longer IRTs.

Molar Accounts of Rate Differences
  • There are several problems with the IRT account
    of rate differences on ratio and interval
  • A logical objection is that showing that the
    reinforcement of IRTs can change behavior does
    not mean that this is what is happening on other
    schedules. In other words, demonstrating that
    IRTs can be selectively reinforced does not prove
    that this occurs on either interval or ratio

Molar Accounts of Rate Differences
  • Molar explanations of rate differences are
    concerned with the global relationship between
    responses and reinforcement.
  • In general terms, the correlation between
    responses and reinforcement produces the
    difference in the rate on interval and ratio
  • Generally, if a high rate of response is
    associated with a higher frequency of
    reinforcement, then subjects will respond
    rapidly. When the increased rate of response does
    not affect the rate of reinforcement, organisms
    do not respond faster.

Molar Accounts of Response Rate
Consider a subject responding on a VR 100
schedule for a 50 minute session. If this subject
responds leisurely at .8 responses per second,
in the 50 minutes, 48 responses per minute,
about 2 minutes per VR 100 or about 30
reinforcers obtained in the 50 minutes. If on
the same VR 100, the subject responded at 2
responses per sec., or 120 responses/minute or
about 48 seconds per VR 100 many more
reinforcers are obtained in the same 50 minutes.
Here, increases in response rate are correlated
with more frequent reinforcement. Increases in
response rate on interval schedules are not
correlated with increases in response
rate. Ratio schedules produce higher response
rates not due to timing on the order of IRT
length but in terms of timing over entire
Molar Accounts of Rate Differences
  • According to supporters of the molar view, this
    correlation between increasing the rate of
    response and the increased frequency of
    reinforcement is responsible for rapid responding
    on ratio schedules.
  • A different correlation between the rate of
    response and the frequency of reinforcement is
    set up on interval schedules.

The VR-VI difference
  • IRT reinforcement
  • IRTs are conditionable
  • Synthetic schedules, merely by making
    reinforcement contingent upon IRTs of specific
    lengths, a VI like performance can be obtained.
  • Response-reinforcer correlation

Analysis of Reinforcement Schedules
  • FR postreinforcement pause theories
  • Fatigue, a larger ratio produces a longer PRP as
    the subject catches its breath.But why not a
    PRP on VRs with large ratios?
  • Satiation, right after consuming reinforcement
    the subject is in a state of relative satiation.
    But PRPs happen after non-consumable reinforcers
  • Remaining response, on a mixed schedule, two or
    more schedules alternate each with its own SD and
    its own reinforcement. If a large ratio
    alternates with a shorter ratio, the PRP will be
    longest after the shorter ratio. A PRP might be
    called a PreRatio Pause

Postreinforcement Pause on Fixed Schedules
  • Molecular accounts of pausing are concerned with
    the moment-to-moment relationships that
    immediately precede reinforcement. Such accounts
    are concerned with the relationship between the
    number of bar presses that produce reinforcement
    and the subsequent postreinforcement pause.
  • In contrast, molar accounts of pausing focus on
    the overall rate of reinforcement for a session
    and the average pause length.

Postreinforcement Pause on Fixed Schedules
  • Generally, it is well established that the
    postreinforcement pause is a function of the
    interreinforcement interval (IRI).
  • As the time between reinforcements becomes
    longer, the PRP increases.

Postreinforcement Pause on Fixed Schedules
  • On fixed-interval schedules, in which the time
    between reinforcement is controlled by the
    experimenter, the postreinforcement pause is
    approximately one-half the interreinforcement
  • For example, on a FI 300-s schedule (in which the
    time between reinforcements is 300 s), the
    average PRP will be 150 s.
  • On fixed ratio, the evidence suggests similar
    control by the IRIas the ratio requirement
    increases, the PRP becomes longer.

Postreinforcement Pause on Fixed Schedules
  • There is, however, a difficulty with analyzing
    the postreinforcement pause on FR schedules.
  • On ratio schedules, the time between
    reinforcements is partly determined by what the
    animal does. That is, the animals rate of
    pressing the lever affects the time between
  • Another problem with ratio schedules, for an
    analysis of pausing, is that the rate of response
    goes up as the size of the ratio is increased.
    Unless the rate of response exactly coincides
    with changes in the size of the ratio,
    adjustments in ratio size alter the
    interreinforcement interval.
  • Thus, changes in postreinforcement pause as ratio
    size is increased may be caused by the ratio
    size, the interreinforcement interval, or both.

A Molar Interpretation of Pausing
  • We have noted that the average PRP is one half of
    the interreinforcement interval.
  • Another finding is that the postreinforcement
    pauses are normally distributed over the time
    between reinforcements.
  • An animal that was sensitive to the overall rate
    of reinforcement (maximization) should come to
    emit pauses that are on average one half of the
    FI interval, assuming a normal distribution.
    Thus, maximization of reinforcement provides a
    molar account of the postreinforcement pause.

Molecular Interpretations of Pausing
  • There are two molecular interpretations of
    pausing on fixed schedules that have some amount
    of research support.
  • One account is based on the observation that
    animals often emit other behavior during the
    postreinforcement pause.
  • For example, rats may engage in grooming,
    sniffing, scratching, and stretching after the
    presentation of a food pellet.
  • Because this behavior reliably follows
    reinforcement, it is said to be induced by the
    schedule. Schedule-induced behaviors may be
    viewed as operants that automatically produce

Molecular Interpretations of Pausing
  • One interpretation is that pausing occurs because
    the animal is maximizing local rates of
  • That is, the rat gets food for bar pressing as
    well as the automatic reinforcement from the
    induced activities.
  • The average pause should therefore reflect the
    allocation of time to induced behavior and to the
    operant that produces scheduled reinforcement
    (e.g., food).
  • At present, experiments have not ruled out or
    clearly demonstrated the induced-behavior
    interpretation of pausing.

Molecular Interpretations of Pausing
  • A second molecular account of pausing is based on
    the run of responses or the amount of work that
    precedes reinforcement.
  • This work-time interpretation hold that the
    previously experienced run of responses regulates
    the length of the postreinforcement pause.
  • Work time affects the PRP by altering the value
    of the next scheduled reinforcement.
  • In other words, the more effort or time expended
    for the previous reinforcer, the lower the value
    of the next reinforcer and the longer it takes
    for the animal to initiate responding (i.e.,
    pause length).

Factors affecting performance on a schedule
  • Quality of reinforcer
  • Rate of reinforcement
  • Delay of reinforcement
  • Amount of reinforcement
  • Level of motivation

Schedule Performance in Transition
  • Steady State occurs when behavior show little
    change from day to day. Ex. Break and run
  • Transition State are periods between steady
    states. Ex. When initially place on any
    reinforcement schedule
  • Most learning takes place when behavior is in

Schedule Performance in Transition
  • After steady-state performance is established on
    CRF, you are faced with the problem of how to
    program the steps from CRF to FR 100.
  • Notice that there is a large shift in the rate of
    reinforcement for bar pressing.
  • If you simply move from CRF to large-ratio value,
    the animal will show ratio strain in the sense
    that it produces longer and longer pauses after


Schedule Performance in Transition
  • Large and sudden increases in schedules may
    produce extinction and is why a slow progression
    to a higher schedule is implemented
  • Transitions in schedules occur in major life
    events. Ex. Divorce
  • Following a divorce a shift in contingencies of
    reinforcement take place.
  • Feelings of depression and loneliness may be
    produced by ratio strain and extinction.

Schedules used to condition response rate 1)
Differential reinforcement of low rates of
responding (DRL) Reinforcers only follow
responses that occur after a minimum amount of
time has passed has elapsed between two
consecutive responses. Ex) DRL 10
sec Response--10 sec delay --gt Response --gt
Reinf If a response occurs during the delay, a
reinforcer is not given, DRLs reinforce
very long IRTs.
2) Differential reinforcement of high rates of
responding (DRH) Reinforcers only follow
responses that occur before a minimum amount of
time has passed. Ex) DRH 10 Response-? 10 sec
delay --gt Response -gt No reinf Two consecutive
responses must occur before the 10 secs to be
reinforced. The IRT between two consecutive
responses must be less than some specified value.
A DRH reinforces very short IRTs.
Sanford (IQ 65) a prisoner in GA prison
system The incentive value of the reinforcer
(points) was higher if Sanford learned faster. 1
grade level in 90 days (DRH 90) ---gt 120
pts (DRH 4) ----gt 900 pts
(DRH 1) -----gt 4700 pts With points exchangeable
for tangible privileges and goods, studying hard
became so reinforcing that Sanford started
skipping recreation time to study. Studying
Sanford completed 5 years of high school in 5
months! He was being differentially reinforced
for learning fast (high rate).
Intelligence and IQ
Some students may be questioning whether the
subject Sanford actually had an IQ of 65. What is
the IQ test measuring, intelligence or the
subjects ability to do well on such tests?
Cognitive psychologists would of course argue
that some partially innate intellectual or
information processing capability is being
assessed. Hence, the notorious bell curve
data showing different races have different
IQs. But what if the IQ test is just measuring
ability to take such tests which could be
affected by variables such as motivation to work
hard??? African American students who took IQ
tests and were given affirmative feedback for
each correct score produced IQ test scores 10 15
points higher than for African Americans tested
without this feedback. The use of feedback had no
real effect on white students taking IQ tests.
Applying Schedules to Smoking
  • The use of drugs is operant behavior maintained
    by the reinforcing effects of the drug.
  • A population of smokers (N60) were assigned to
    one of three groups Progressive reinforcement
    (N20), fixed rate reinforcement (N20), and
    control (N20). Carbon monoxide testing detected
    the abstinence from smoking
  • Money was the reinforcement for the experiment to
    implement response cost.

Applying Schedules to Smoking
  • The progressive reinforcement group was given
    3.00 for passing initial carbon monoxide test
    and .50 for second and third consecutive
    passings. On the third consecutive passing a
    bonus of 10 was given. This schedule was
    repeated. Failing a CO test would not be
    reinforced and the payment was returned to 3.00.

Applying Schedules to Smoking
  • The fixed reinforcement group were paid 9.80 for
    passing each test. No bonuses or resets for
  • The control group was paid the same as the
    average payment to the progressive reinforcement
    group unconditional to their CO levels.

Applying Schedules to Smoking
  • Smokers in both experimental groups passed 80 of
    CO tests while the control group passed 40 of
    the tests
  • 22 of the progressive group resumed smoking
    while 60 of the fixed and 82 of the control
    group resumed smoking.
  • Progressive reinforcement schedule appears
    effective in the short run of abstinence of
    smoking. Further research is needed to indicate
    if this schedule is effective for long run