Lecture Note For PSYB45, Lecture 3
Getting Behaviour to Occur More Often with Positive Reinforcement
- An event that, when presented immediately following a behaviour, causes the
behaviour to increase in frequency (or likelihood of occurrence). The term
positive reinforcer is roughly synonymous with the word reward.
- the principle of positive reinforcer
- It states that if, in a given situation, somebody does something that is followed
immediately by a positive reinforcer, then that person is more likely to do the
same thing again when he or she next encounters a similar situation.
- Examples of positive reinforcement with desirable behaviour outline in table
3-1 on page 32.
- Refers to the observation phase prior to the reinforcement program
- This is where you observe the individual in their natural environment and their
natural behaviour before the behaviour modification treatment is applied.
- This is done to compare the results of before and after the treatment
- Can be presented in a graph.
- Behaviours that operate on the environment to generate consequences, and in
turn influenced by those consequences
- Also called operant responses
- Operant behaviours that are followed by reinforcers are strengthened while
operant behaviours that are followed by punishers are weakened.
Factors Influencing the Effectiveness of Positive Reinforcement
1) Selecting the behavior to be increased
! The behaviors to be reinforced must first be identified specifically. By
being specific with your target behavior, you a) help to ensure reliability
of detecting instances of the behaviour and changes in its frequency,
which is the yardstick by which one judges reinforcer effectiveness and b)
increase the likelihood that the reinforcement program will be applied
2) Choosing Reinforcers (“ Different strokes for different folks”)
!Everyone doesn’t share the same reinforcement unlike food for when
someone is hungry, or candy for children. It is important to use a
reinforcer that is effective with the individual which whom you are
working. Ex! Dianne was asked to read some sentences and some of the
reinforcers were candy, if she read the sentences correctly. But she did
very poorly on the task, and the reinforcement she got (candy) was
something she didn’t like. Until after we saw her playing with a toy purse
that she enjoyed. Using the toy purse as the reinforcer, this dramatically
improved on Dianne’s performance on the task. Thus, not everyone
enjoys the same reward.
! Most positive reinforcers can be classified under five somewhat
1) Consumable- items one can eat or drink
2) Activity- opportunities to do an activity like watch TV, play
3) Manipulative- opportunities to play with a toy, ride a bike,
4) Possessional- sit in your favorite chair; wear your lucky shirt,
or some other item that one can temporarily
5) Social- affectionate hugs and pats, praise, nods, smiles or
- a considerable amount of trial and error for a particular individual may
be involved in finding an appropriate reinforcer for a particular individual.
-you can never really be sure that an item is a reinforcer for someone until
it has been demonstrated to function as such for that person. In other
words, an object or event is defined as a reinforcer only by its effect on
! If it increases the desirable behaviour, then it is an appropriate
reinforcer for that individual.
3) Motivating Operations
!Most reinforcers will not be effective unless the individual has been
deprived of them for some period of time prior to their use.
!Deprivation- to indicate the time, prior to a training session, during
which an individual does not experience the reinforcer.
!Satiation- refers to that condition in which the individual has
experienced the reinforcer to such an extent that it is no longer reinforcing.
! Motivating Operations (MOs) - events or conditions-such as
deprivation and satiation—that a) temporarily alter the effectiveness of a
reinforcer, and b) alter the frequency of behaviour reinforced by that reinforcer
Ex! food deprivation not only establishes food as an effective reinforcer
for the person who is food deprived it also momentarily increases various
behaviours that have been reinforced with food.
!Deprivation is an example of an establishing operation because it
temporarily increases the effectiveness of a reinforcer whereas satiation is an
example of an abolishing operation because it temporarily decreases the
effectiveness of a reinforcer.
4) Reinforcer Size
! The size (or amount or magnitude) of a reinforcer is an important
determinant of its effectiveness. The size of the behaviour should be
sufficient to strengthen the behaviour that you want to increase.
! Ex. If you pay 25 cents to a boy to shovel snow, he won’t do it. If you
paid him $25 dollars, then he would do it because it’s a bigger reinforcer.
5) Instructions: Make Use of Rules
!Instructions can facilitate behavioral change in several ways.
1) Specific instructions will speed up the learning process for individuals
who understand them.
2) Instructions may influence an individual to work for delayed
reinforcement. Ex! getting an A in this course for which you are
using this book, is delayed several months from the beginning of this
3) Adding instruction to reinforcement program may help to teach
individuals to follow instructions.
6) Reinforcement Immediacy
! For maximum effectiveness, a reinforcer should be given immediately
after the desired response.
! Ex. When the husband picked up his wife’s underwear and placed it in
the laundry, the wife immediately thanked her husband. If she waited till
the next morning to say thanks, it wouldn’t have had the same effect.
! Be aware of the example of the arriving to work on time. When
Fernando gets reinforced every time for arriving to work on time, his
attendance to work on time increase immediately.
Direct-acting effect- of the principle of positive reinforcement is the
increase frequence of a response because of its immediate reinforcing
Indirect-acting Effect- of positive reinforcement is the strengthening of a
response (such as Fernando leaving for work earlier) that is followed by a
reinforcer (earning 2 pesos) even though the reinforcer was delayed.
7) Contingent Versus Noncontingent Reinforcement.
-when a behaviour must occur before a reinforcer will be presented, we s
ay that the reinforcer is contingent on that behavior.
-if a reinforcer is presented at a particular time, regardless of the preceding
behaviour, we say that the reinforcer is noncontingent.
-Ex! swimming example! reinforcers must be contingent on specific
behaviours that you want to improve.
! A noncontingent may increase an undesirable behavior. They get to
have fun time at the end of the class regardless of how they did in their
-When a behaviour is accidently followed by a reinforcer maybe be
strengthened even if it did not actually produce the reinforcer is called an