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Reinforcement

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Reinforcement The most basic and important principle of

applied behavior analysis Reinforcement is used to strengthen behavior Another way to say this is that reinforcement

increases behavior Reinforcement occurs when a consequence of a

behavior increases the probability that the behavior will occur in the future

Consequence can be the addition OR the removal of a stimulus

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Types of Reinforcers

Primary Unconditioned-

Food, water, oxygen

Secondary Conditioned

Neutral stimuli which acquire reinforcing properties through pairing with unconditioned reinforcers

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Secondary Reinforcers

Tangible / Edible /Activity Social/Attention Escape Sensory Generalized: effectiveness does not depend

on a single kind of deprivation; Less likely to be affected by satiation

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Selecting Reinforcers How do we know what materials will serve as

a reinforcer for a person: Conduct a preference assessment Test these preferences to see what materials

serve as a reinforcer ALWAYS keep in mind…what serves as a

reinforcer for me is different than what serves a reinforcer for you I LOVE lima beans…I will do anything for lima

beans…would you??? How many times have you told a student what

they will work for???

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Conduct a Preference Assessment Ask

Ask the individual Ask those who know the individual best

Observe Look to see what the student gravitates toward…

For our more challenging students or lower functioning students…keep an open mind.

Do a formal Preference Assessment Paired Choice Multiple Stimulus

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# ITEM # ITEM

1 4

2 5

3 6

Paired Choice Preference Assessment First Choose 6 items that you perceive to be

preferred for the student. Test food against other food items and test activities against other activities

Be sure the student has tasted or played with all items before you start the assessment.

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TRIAL LEFT RIGHT TRIAL LEFT RIGHT TRIAL LEFT RIGHT

1 1 2 11 5 2 21 3 5

2 3 2 12 4 3 22 6 2

3 2 6 13 1 5 23 1 4

4 1 3 14 5 3 24 4 5

5 6 5 15 4 1 25 6 3

6 3 6 16 2 5 26 2 4

7 2 3 17 4 2 27 2 1

8 5 1 18 5 4 28 6 4

9 4 6 19 6 1 29 3 1

10 5 6 20 3 4 30 1 6

Paired Choice Preference Assessment You will present the items as indicated in the chart below.

By presenting the items in the specified location you will be able to see if the student is indicating a preference or if they are only selecting the items on the left or the right.

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Paired Choice Preference Assessment Present both numbered items simultaneously. Place the first

item on your left, the second on your right. If the student doesn’t select one, say, “Take one.” Record any touch to an item as a selection. Circle the selected

items. If the item is an edible, allow the student to consume it before

going on. If the item is an activity, let the student play with it for 30

seconds. Block any attempts to touch both items simultaneously. If no response is made in 10 seconds, record “NR” and move

to the next trial. Calculate the percentage of trials that each item was selected.

Those items selected 80% or more of opportunities are most probably going to function as positive reinforcers.

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SUMMARYITEM 1 SELECTED _____ OUT OF 10 OR _____% OF OPPORTUNITIESITEM 2 SELECTED _____ OUT OF 10 OR _____% OF OPPORTUNITIESITEM 3 SELECTED _____ OUT OF 10 OR _____% OF OPPORTUNITIESITEM 4 SELECTED _____ OUT OF 10 OR _____% OF OPPORTUNITIESITEM 5 SELECTED _____ OUT OF 10 OR _____% OF OPPORTUNITIESITEM 6 SELECTED _____ OUT OF 10 OR _____% OF OPPORTUNITIES

Finally, calculate the percentage of trials that each item was selected. Those items selected 80% or more of opportunities are most probably going to function as positive reinforcers.

Paired Choice Preference Assessment

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1._____________ 2._____________ 3._____________ 4._____________

5._____________ 6._____________ 7._____________

Multiple Stimulus Preference Assessment without replacement Seven items will be included in each assessment. Collect the items that are going to be assessed

and list them on the data sheet. Allow the student to sample each item prior to

initiating the assessment (i.e., taste the food items or manipulate the leisure items for a short period of time).

Sequence items randomly in a straight line on the tray about 5 inches apart.

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Instruct the student to “pick one.” Immediately after the selection, remove the remainder of the

items to prevent multiple selections. Record the selected item on the data sheet to the

corresponding number. For example, the first item selected would be written down on the space marked “1.”

After one item is selected, it is not replaced. For example, after the first presentation of 7 items, only 6 will be presented next.

Prior to the next presentation, rotate the remaining items on the tray by taking the item on the left end and moving it to the right end, then shifting the other items so that they are again equally spaced.

Present the remaining items and repeat the procedure described above.

Multiple Stimulus Preference Assessment without replacement

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Multiple Stimulus Preference Assessment without replacement Continue until all of the items are selected or

until the student does not make a selection within 30 s from when they were told to “pick one.” In the latter case, end the session and record the remaining items as “not selected.”

Summarize the data by giving each item a ratio based on the number of times that it was selected (0 or 1) over the number of times that it was available (1 to 7). For example, the first four selected items will be given 1/1, 1/2, 1/3, and 1/4, in the order that they were selected. If the student selected four items but did not select any more on the fifth presentation, then all of the unselected items would be given the ratio 0/5.

Preference Assessment #1

Order of items selected

# times chosen /# of timesavailable

1.

2.

3.

4.

5.

6.

7.

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•Conduct 5 sessions in the manner described above, and then sum the ratios for each item across the sessions. For example, if during five sessions an item produced ratios of 1/2, 1/3, 1/2, 1/4, and 0/5, the overall sum would be 4/16 and the conversion would yield a score of .25 indicating that the item was chosen on 25% of the trials in which it was available.•Once the final percentage score is calculated for each item, rank the items (from high to low) to indicate which items are predicted to be the most effective reinforcers.

Multiple Stimulus Preference Assessment without replacement Summary (high to low)

Item Total%Selected

1.

2.

3.

4.

5.

6.

7.

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Reinforcement

Do quick/informal reinforcer assessments throughout teaching Once we have an idea of student preference,

present 3-5 of these items and ask the student to pick one.

Take the top two items that the student indicated interest in and put those items on their choice board.

Since those items were preferred in the moment the student will be more motivated to work for those items.

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Three-Term Contingency- how this relates to reinforcement….

Antecedent Stimulus

Response/ behavior Consequence

Cole signs cookiesCole see cookies Cole Gets cookies

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Antecedent Stimuli

A stimulus that precedes a behavior in time Antecedents are any stimuli that occurs BEFORE

a behavior Some stimuli signal the availability of

reinforcement… This is an Sd (discriminative stimulus) The antecedent can be something the person sees in the

environment. It can be an instruction or something someone hears.

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Consequence

A stimulus that follows a behavior in time

Consequences are any stimuli that occur AFTER a behavior

Some stimuli produce desirable outcomes…reinforce the response/behavior

Some stimuli produce undesirable outcomes…decrease behavior

A B C

‘Put on your coat’

Bob puts on his coat

Bob goes for a walk

Cole thinks..I want to go for a walk

Cole signs walk

Teacher says, “Not right now”

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What Are the Two Types of Reinforcement? Positive Reinforcement

Stimulus is added to the environment Behavior increases

Negative Reinforcement Stimulus is removed from the

environment Behavior increases

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Positive Reinforcement

Presentation of a preferred stimulus after a behavior we want to increase or maintain

Examples: Giving a student a snack after completing their

work Your boss telling you that you did a good job on

a project at work

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Negative Reinforcement Removal of an unpleasant or non-preferred stimulus

after a behavior we want to increase or maintain Examples:

Alarm clock sounds….push off button…Alarm stops- you are more likely to push the off button in the future

Alarm clock sounds….you push the volume up button…Alarm gets louder- you are less likely to push the volume up button when you want to turn the alarm off…NOT NEGATIVE REINFORCEMENT…you weakened the behavior

Student is overwhelmed by the noise in the cafeteria... He says can I go back to class…he goes back to the quiet room- he is more likely to ask to go back to class when in the loud cafeteria.

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Examples Reinforcement: Yes or No? Positive or Negative?

The teacher tells Joe to sit down, he sits down, and Joe immediately gets a piece of candy. Joe is more likely to sit down in the future when asked.

The teacher asks Joe to sit down, Joe screams, the teacher lets Joe leave. Joe is more likely to scream in the future.

The teacher tells Joe to sit down, he sits down, Joe gets a piece of candy. Joe never sits down again when asked.

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Satiation and Deprivation Satiation is a temporary state that occurs

after a period of time with adequate access to a reinforcer so that the stimulus is not currently acting as a reinforcer

Deprivation is a temporary state the occurs after a period of time without access to a reinforcer

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Effectiveness of Reinforcement Current Environment

Timing - immediate to delayed Frequency – continuous to intermittent Consistency - according to established

schedule-do not make random changes!

Amount of reinforcement - proportional to effort.

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Delivering Reinforcement Schedules of Reinforcement

A rule that establishes the probability that a specific occurrence of a behavior will produce reinforcement.

Tells you how often to reinforce behavior

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Schedules of Reinforcement Continuous reinforcement (CRF)

every response is reinforced Intermittent reinforcement

Some responses are reinforced and others aren’t

An average number of responses are reinforced

Extinction (EXT) no occurrence of the behavior is reinforced

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Continuous Reinforcement Use continuous reinforcement when first

teaching and establishing a behavior Not a good schedule of reinforcement for

maintaining behavior Satiation Susceptible to extinction

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Intermittent Reinforcement Some occurrences, but not all

occurrences of the behavior will be reinforced

Used to maintain established behaviors Includes schedule thinning

Gradually extending schedule Think about slot machines at the casino

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Basic Intermittent Schedules of Reinforcement Ratio: number of responses must be emitted

Interval: interval of time elapses before response can be reinforced

Fixed & variable: constant vs. average #

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Fixed Ratio Schedule of Reinforcement A given number of responses must be emitted

before reinforcement Ex: FR4 correct responses Post reinforcement pause:

period of time after reinforcement in which the subject ceases to respond

Rate of responding is high – work rapidly Larger ratio requirements = higher responding

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Variable Ratio Schedule of Reinforcement # of correct responses prior to reinforcement varies # represents average number of responses required for

reinforcement Ex: slot machines

getting called on in class Produce steady rates of response No post reinforcement pause: next response may produce

reinforcement Rates of responding can be high if gradually extended over time

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Fixed Interval Schedule of Reinforcement

The first correct or desired response after a designated and constant amount of time produces the reinforcer Time must elapse Correct or desired response is emitted New interval begins

Ex: mail delivery—many trips, only R+ after mail delivered Response rate increases toward end before delivery of

reinforcement (scallop effect) Produces slow to moderate rates of responding Has post reinforcement pause

Ex: term paper

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Variable Interval Schedule of Reinforcement Reinforcer follows the first correct response after an

average interval of time passes Ex: busy phone- long or short interval before

reinforcement is available eventually produces answer does not stop attempts

Slow to moderate, stable rate of responding Hesitation between responses

pop quizzes=consistent study

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Benefits of an Intermittent Schedule of Reinforcement

Maintains behavior Resistant to extinction (more so than CRF) Produces high rates of the behavior Much more natural schedule of reinforcement Controls for satiation Cost effective

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Conclusion

Effective use of reinforcement is one of the most important skills to learn

Effective reinforcement allows us to increase and maintain appropriate behaviors

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Reinforcement is more than JUST rewards We need to start to think…how can I make my instruction more reinforcing???? think about what the students like…computer, art’s

and crafts, food…. How can I embed my teaching into fun highly

motivating activities? How would they respond to painting their spelling

words, making their words out of play-doh, making a powerpoint presentation, hearing a story read through powerpoint, making an imovie….