Differential reinforcement (DR) is a special application of reinforcement designed to reduce the occurrence of interfering behaviors (e.g., tantrums, aggression, self-injury, stereotypic behavior). The rationale for DR is that by reinforcing behaviors that are more functional than the interfering behavior or that are incompatible with the interfering behavior, the functional behavior will increase and the interfering behavior will decrease. A variety of differential reinforcement strategies can be used to increase positive behaviors and decrease interfering behaviors. DR includes the following steps:
Step 1. Identifying the Interfering Behavior
- Teachers/practitioners define the target behavior.
- Teachers/practitioners gather information from team members regarding the following aspects of the interfering behavior:
The first step in using a DR procedure is to identify the interfering behavior. Interfering behaviors are disruptive behaviors such as screaming or aggression or repetitive/stereotypic behaviors (e.g., lining up toys or blocks, spinning objects, etc.) that interfere with learning.
In addition to identifying the specific behavior that is interfering with learning, gathering information from team members regarding certain aspects of the interfering behavior will be helpful.
i.Topography, or what the interfering behavior looks like (e.g., banging arms against the table);
ii.Frequency, or how often the behavior happens (e.g., from once or twice per day to a dozen or more times per day);
iii.Intensity, or how severe the behavior is (e.g., if the behavior is biting, how hard does the learner bite and does he cause tissue damage);
iv.Location, or where the behavior is occurring (e.g., in gym class, on the playground, during math class); and
v.Duration, or how long the behavior lasts (e.g., a tantrum that lasts a few minutes or that can last for an hour).
This information can be summarized to aid in assessing the possible functions of the interfering behavior. For example, knowing that Joey loudly shouts profanities three to four times for 30 seconds or more per instance when in the lunchroom provides specific information about the interfering behavior that can be valuable when planning intervention.
Step 2. Determining the Function of the Interfering Behavior
Teachers/practitioners use functional behavior assessment to identify the function of the interfering behavior.
An important part of determining the function of the interfering behavior is interviewing team members about the nature of the problem behavior. To do so, you will need to complete a functional behavior assessment that will allow you to identify the current antecedents and consequences. For more information about this procedure, please see Functional Behavior Assessment: Steps for Implementation (National Professional Development Center on Autism Spectrum Disorders, 2008).
Step 3. Identifying Data Collection Measures and Collecting Baseline Data
- Teachers/practitioners identify data collection measures to be used to assess the interfering behavior before implementing the intervention.
- Teachers/practitioners gather baseline data on the interfering behavior.
- Teachers/practitioners decide who will collect the initial data.
When collecting data for DR, it is important to focus on the frequency, topography, and intensity/severity of the behavior.
The data collection measures identified above are used, along with the information gathered in Steps 1 and 2, to determine the nature of the interfering behavior prior to the intervention.
During the baseline phase, it is important to collect data for a long enough period to see if there is some consistency in the behavior. Teachers/practitioners should decide how long data will be collected (e.g., one week, two weeks) and what will happen if not enough data emerges to appropriately inform intervention (e.g., redesign the data collection method, observe at a different time). Baseline data collection allows teachers/practitioners to assess the impact of the intervention on the interfering behavior over time. Typically, the behavior should be observed for three or more days in different settings (e.g., science class, music).
For example, it might be easiest for a paraprofessional to collect data across the day. The team also may decide that it would be easier to have an objective observer collect data, rather than relying on a classroom teacher who is in the middle of a lesson.
Step 4. Selecting a Differential Reinforcement Procedure
There are many types of differential reinforcement procedures included in the overall designation of DR. They include:
- Differential reinforcement of other behaviors (DRO; e.g., reinforcing not screaming);
- Differential reinforcement of alternative behaviors (DRA; e.g., reinforcing shaking hands to replace slapping);
- Differential reinforcement of incompatible behaviors (DRI; e.g., reinforcing appropriate language to replace swearing);
- Differential reinforcement of lower rates of behavior (DRL; e.g., reinforcing a behavior when it happens at a lower rate than before, such as shouting less often as he used to).
- Differential reinforcement of higher rates of behavior (DRH; e.g., reinforcing a behavior when it happens at a higher rate than before, such as raising his hand more often than he used to instead of shouting out).
When deciding which procedure to use, teachers/practitioners:
- identify functionally similar behaviors (behaviors that serve the same functions, such as saying, “Help please” instead of grunting) that learners already have in their repertoire;
- determine the type and amount of functional skills (skills the learner currently has that are functional alternatives to the interfering behavior—e.g., tapping the teacher on the arm to secure her attention instead of screaming);
- determine how frequently these desired behaviors occur;
- consider the topography (what the behavior looks like), the frequency of the interfering behavior, how severe the behavior is, how the behavior is affecting the environment, and where the behavior is most likely to occur; and
- consider their own professional judgment and comfort level with the proposed procedure.
Step 5. Creating an Intervention Plan
When creating a DR intervention plan, teachers/practitioners need to address several features.
- Teachers/practitioners should define other procedures that will be incorporated (e.g., extinction, functional communication training) with the differential reinforcement procedure. For example, a teacher/practitioner who decides to use DR for biting may also need to use functional communication training to teach the learner how to make requests.
- Teachers/practitioners administer a reinforcer assessment to identify learner-preferred objects and activities that can be used as rewards for demonstrating the replacement behavior. The goal is to motivate the learner with tangible rewards for demonstrating a more positive, acceptable behavior that serves the same function as the problem behavior. The reinforcer assessment can be as informal as displaying a variety of objects or pictures of objects/activities related to the learner’s interest and observing what the learner consistently chooses. In addition, asking the learner (if possible) and parents/family members about preferred reinforcers should be considered. Keep in mind that the learner’s interest in reinforcers may decrease or change over time. For example, the learner’s initial desire to “work” for time on the computer after completing assignments may no longer be a preferred reinforcer. When learner preferences change, other favorite objects/activities can be offered for selection. For more information about reinforcer assessment, please see the Reinforcement Module (National Professional Development Center on Autism Spectrum Disorders, 2009) at www.autisminternetmodules.org.
- Teachers/practitioners decide on a schedule of reinforcement (how frequently the reinforcer is delivered). For example, you may decide whether the learner gets a reward every time he engages in the replacement behavior or a reward for going 10 minutes without engaging in the interfering behavior.
- Teachers/practitioners establish criteria for changing the schedule of reinforcement. For example, after three sessions in which the learner is reinforced every 5 minutes, he/she will be reinforced every 10 minutes for the following three sessions. For more information about this procedure, please see Positive Reinforcement: Steps for Implementation (National Professional Development Center on Autism Spectrum Disorders, 2008).
- Teachers/practitioners specify the timeline for data collection. For example, the team decides that data should be reviewed after one week of implementation to identify the following week’s schedule of data collection (to monitor student progress).
- Teacher/practitioners clearly write out the intervention plan and make it available to other team members.
Step 6. Implementing the Intervention
Once an intervention plan has been developed, it must be implemented. During implementation of a DR procedure, two components should be addressed.
Before the interfering behavior occurs, teachers/practitioners should:
i.choose which behavior to reinforce based on the intervention plan.
ii.explicitly teach the replacement or alternative skills.
iii.continuously reinforce the other/low rate/alternative/incompatible behaviors.
iv.match the reinforcement to the function of the behavior.
- If or when the interfering behavior occurs, teachers/practitioners prompt and immediately respond to the alternative behavior by:
- After the plan has been in place for a certain number of days, as documented in the intervention plan (see step 5.3), teachers/practitioners can alter the schedule or reinforcement.
This may be done by using functional communication training, task analysis, graduated guidance, or other kinds of direct teaching procedures such as discrete trial training. For example, if the replacement behavior is requesting a break, teachers/practitioners may need to teach the learner how to request a break using pictures or scripts.
To continuously reinforce, rapidly reinforce every instance of the replacement behavior. For example, if you are reinforcing a learner for remaining seated, provide reinforcement the entire time the learner is in his/her seat.
Because the function of a learner’s interfering behavior can change, it is important to confirm that your intervention always matches the hypothesized function of the interfering behavior. For example, the function of a calling out behavior may initially be for attention and may later shift to escape. The DR procedure must also change to reinforce the function of the replacement behavior (i.e., not calling out).
i.prompting frequently to assure that there are enough instances of the desired behavior to reinforce and
If the desired behavior does not occur, prompt and immediately reinforce the prompted desired behavior. For example, if the learner is calling out to get attention, prompt him to raise his hand often so that he can be reinforced. Prompting the desired behavior immediately after it occurs will increase the likelihood of the learner displaying the desired behavior. For more information about this procedure, please see “Least-to-Most Prompting: Steps for Implementation” (National Professional Development Center on Autism Spectrum Disorders, 2008).
For example, if a learner is being reinforced every hour and meets the criteria for change according to the intervention plan, the learner may then be reinforced only twice per day.
Step 7. Collecting Outcome Data
To determine the effectiveness of the DR procedure and whether modifications are necessary (e.g., a new interfering behavior is presenting), teachers/practitioners must regularly collect outcome data by:
For example, if the frequency of the original behavior was assessed during baseline, assess the frequency of the desired behavior to monitor progress.
Step 8. Reviewing and Modifying the Intervention Plan
- Teachers/practitioners review the outcome data and discuss the results with team members.
- Teachers/practitioners summarize the results, making sure to include both baseline and outcome measures.
- Teachers/practitioners identify any new interfering behaviors that may have emerged and assess them for function.
- Teachers/practitioners modify the intervention plan depending on the baseline and outcome data.
- Teachers/practitioners conduct ongoing checks of intervention effectiveness.
It is possible that new interfering behaviors will have the same function as the extinguished behavior. If this is the case, a similar intervention may work.
For example, if the data show that a learner’s hitting behavior has improved minimally, teachers/practitioners may need to modify the plan to reinforce the desired behavior more frequently.
Interventions will likely need to be reviewed and modified several times before the interfering behavior is extinguished.