In the previous section we discussed that every behavior is preceded by a stimulus and followed by a consequence. So when a student sees a stimulus (e.g., sight word "stop") he or she should respond to that stimulus (e.g., says the word "stop"). Sometimes students do not respond to the stimulus or respond incorrectly to the stimulus. When this happens a prompt should be added to help the student learn; this is also known as transfer stimulus control.
So when do you know if learning has occurred? You know when the individual consistently makes a response in the presence of a specific discriminative stimulus. This is called stimulus control. This is what you want as a teacher. We want our students to respond independently to an S-Dee or discriminative stimulus versus us having to prompt them to respond.
There are a couple of terms to know that will help when progressing through the rest of this module. The first term is target stimulus. This is the S-Dee that is expected to ultimately control the occurrence of the behavior. It is the natural cue to respond. Another important term to know is controlling prompt. Controlling prompts are stimuli that are added to the target stimulus or after the target stimulus to help the student make the target response. It might be a physical prompt, a verbal prompt, or a positional cue.
If the target stimulus does not control the behavior, it needs to be paired with a stimulus that does in order to develop stimulus control. This is called a prompt. For example, when shown cards with sight words and told “find the word house” the student does not select the word house. Then something is added to the flash card or task direction.
Prompting strategies are specific strategies of delivering a prompt so that the student will learn how to respond in the presence of that target stimulus (or SD). There are all different types of prompts. The table below provides a look at a variety of instructional prompts and examples of each.
- pointing, head nods, hand motions
-Specific verbal prompts
-Nonspecific verbal prompts
Read the word restroom, pick up the spoon
-Turn the page.
-How do we keep the story going?
|Prerecorded auditory prompts|
-Words, symbols, signs
-Match to sample
Picture schedule of the events of the day
-Picture and word instructions for a task
-Six pencils= the number 6
Peer demonstrates turning a page
Teacher demonstrates using a paper towel to dry hands
Physical assistance to complete a skill
-A tap to the elbow to encourage a choice for lunch
-Hand over hand assistance for writing the first letter of name
|Mixed prompts||Pointing to the response options and repeating the comprehension question|
There are two types of prompting strategies, response prompting strategies and stimulus prompting strategies.
Stimulus prompts are prompts that are added to the materials. Three types of stimulus prompts are noted above. First, color coding the correct answer is a stimulus prompt because the prompt, which is the color, is embedded into the actual materials. Another example is a position cue. This is when you would place the correct answer closer to the student. Finally, a third example is making the correct answer more salient in some way. There are several ways to prepare the materials to make the correct answer more salient; for example, placing a red dot in the corner of a target sight word, placing pictures behind the target sight word, or bolding the correct answer all make the correct response more salient.
The other type of prompting system is a response prompting system. Response prompting systems are those in which the prompt is delivered by the teacher after, or concurrently with, the presentation of the target discriminative stimulus. Verbal prompts, model prompts, and physical prompts are just a few of the prompts that can be added by the instructor. There are six common response prompting strategies shown in the chart below, each of which will be discussed in more detail.
Time delay is known as an errorless teaching strategy. It is a response prompting system where the prompt is faded using increments of time. Typically one type of prompt is chosen (e.g., model prompt) and used throughout instruction. Time delay starts with a zero delay round. This is when the prompt is delivered at the same time as the stimulus is presented so that the student can correctly respond without making an error. For example, the teacher says “Point to the word ‘precipitation’” while pointing to the correct answer “precipitation” in an array of science terms. After several rounds of zero-delay instruction, the teacher will add a time delay. There are two types of time delays, constant and progressive. In constant time delay the increments of time added after presenting the target stimulus stays constant (or the same; typically 2 to 4 seconds). If the student does not respond within the set amount of time, a prompt is delivered. Again, typically the prompt stays the same.
For example, after completing several rounds at a zero-second delay the teacher will present the target stimulus of the sight word ‘precipitation’ ask “What word?” and wait for a set time of 4 seconds for the student to respond. If no response is provided the teacher uses a model prompt to point to the word ‘precipitation’ and asks the student to respond. The video below demonstrates how to teach sight words using constant time delay. Note that this is an example of one-on-one instruction in a receptive format.
In this video, the teacher, Jennifer, starts off teaching the vocabulary words at a zero-delay round. After a few trials of the student doing well with the zero delay round Jennifer moves to the delay round where she uses a 4 second delay. Note that on the teaching trial where she presents the word ‘confused’, she repeats the stimulus and talks through the wait time. When using constant time delay avoid a ‘begging system’, meaning avoid repeating the task direction. Present the task direction once and allow the wait time to occur. If the student does not respond, prompt and move on, even if it is felt that the student knows the target word. This teaching procedure is very precise and systematic. The delivery is usually pretty fast paced. On several trials, the student goes for the wrong answer; Jennifer quickly redirects the student instead of allowing the student to focus on the wrong answer. Note that she also does not highlight the wrong answer in any way. She does not say, “No! That is not the word ‘package’; this is the word ‘funeral’”. If she had said this it would have highlighted the incorrect answer instead of focusing only on the correct answer. Another great strategy Jennifer does when teaching is when the student gets the answer correct all on his own, Jennifer ups the reinforcer by giving him a high five. Finally, Jennifer mixes up the words between each teaching trial. This prevents the student from memorizing the word because of its position. You may want to watch this short video again now that you know some key things for which you want to look.
The next video is an example of how you would teach sight words using constant time delay in an expressive format. In this video, Jennifer, the teacher, starts off by presenting the zero delay round by showing the student one word at a time and asking the student to repeat the word after her. During the delay round, she continues to present one word at a time and asks the student to read the word on his own. She gives him 4 seconds to respond and if he does not, she prompts him by reading the word and asking him to repeat her. If he starts to read the wrong word she interrupts and says the correct word asking him to repeat.
Notice how Jennifer shuffled the cards between trials. This ensures the student knows the word rather than just memorizing the order of the words. Also, Jennifer does a nice job providing a stronger reinforcer (high five) when the student gets the word correct on his own.
The next video is an example of how you would teach vocabulary definitions using constant time delay. In this video the teacher says, “I’m going to say a definition and I want you to point to the correct word for the definition.” The teacher uses the definition as the stimulus to cue the student to find the corresponding word.
This can also be done with pictures that match the word. Students can demonstrate comprehension of the word by matching the word to the picture.
The final video is an example of how you would use constant time delay to teach sight words in a group setting. This is a video provided by Attainment Company and shows constant time delay to teach sight words during the Early Literacy Skills Builder (Browder, Gibbs, Ahlgrim-Delzell, Courtade, & Lee, 2007), which is a literacy curriculum designed to teach students with significant disabilities emerging literacy skills through a systematic, direct instruction approach.
In this video the teacher, Suzanne, starts off with a zero time delay and then moves into the delay round. She uses attentional cues and observational learning to maximize student learning. Notice the fast paced instruction that Suzanne uses. Do you want to watch the video again to focus this time on the cues?
In progressive time delay the increments of time added after presenting the target stimulus progressively increase. It can increase by increments of 1 second or by increments of 2 seconds at a time. If the student does not respond within the set amount of time for that specific trial, a prompt is delivered. Typically the increases in time have a ceiling that the teacher has set (e.g., 8 seconds). For example, after completing several rounds at a zero-second delay the teacher will present the target stimulus of the sight word ‘precipitation’ and ask “What word?” and wait 2 seconds for the student to respond. On the next trial the wait time will increase to 4 seconds and the next trial to 6 seconds and so on.
Simultaneous prompting is another response prompting system that has been used successfully with both discrete as well as chained tasks. When using this prompting system, after the stimulus is presented, the controlling prompt (e.g., model prompt) is immediately delivered. This is exactly what happens during the zero delay rounds of time delay, but with simultaneous prompting, the prompt is always delivered immediately after the stimulus at zero delay. So, how can you tell if the student has learned anything? Well, you need to check for learning by conducting a test (probe) session. During this session you will just test and not prompt. So if the student gets something wrong, you do not say anything and move on with testing. Also, if the student gets it correct, you also should not praise, rather just praise for their overall participation in the activity. Review your data after a testing session as the data will show if learning has occurred or not. If learning has not occurred, you need to continue with instruction using simultaneous prompts.
System of least prompts is also known as least-to-most prompt system or least intrusive prompt system. This prompt strategy uses a prompt hierarchy in which prompts are provided, as needed, from the least intrusive prompt to the most intrusive prompt. In the system of least prompts the teacher selects about three types of response prompts and sequences in order of intrusiveness (e.g., verbal, then model, then physical guidance). Although “intrusiveness” is subjective, generally physical assistance is considered more intrusive than other forms of prompting.
Once the hierarchy of prompts is chosen, the instructor plans a constant wait time (usually 3 to 5 seconds) to be provided after the discriminative stimulus and between prompts to provide the student a chance to respond with the least intrusive prompt possible. After the presentation of the stimulus, the instructor waits a predetermined amount of time (e.g., 4 seconds) for the student to respond independently. If the student does not respond after the predetermined amount of time the instructor would then provide the first prompt in the predetermined prompt hierarchy (e.g., verbal prompt), and again, wait the predetermined time for the student to respond. This process continues (e.g., model prompt) until the student responds or the most intrusive prompt in the hierarchy has been given (e.g., full physical guidance). If the student makes an error during the instructional trial, the instructor would block the error and redirect to the correct stimulus and the instructional trial would be over.
The system of least intrusive prompts is considered to be “self fading,” because the teacher uses less assistance as the student begins to respond. This self fading can be promoted through the use of praise and other reinforcers. For example, once the student can respond with a verbal prompt, the instructor no longer praises responses when the student waits for a model or physical guidance in order to shape progress towards independence. The video below shows how the system of least prompts was used to teach a student to use the phone to call her mother. The prompt hierarchy chosen was a verbal, model, and physical prompt with a 4 second wait time before each prompt.
In this video the instructor used a verbal, model, physical prompt hierarchy on each step of the task analysis to use a phone. In the first step, to pick up the phone, a verbal, model, and physical prompt were needed before the student completed the step. In the second step, to dial the number, the student needed a verbal prompt, then a model prompt before completing the step. Notice the reinforcer for the step where the student only needed a model prompt was a bigger reinforcer than the step where she needed a physical prompt.
In the next video the system of least prompts is used to teach comprehension of text read aloud. The teacher asks the student a literal recall question and the first level prompt is to reread the line of text containing the answer and reask the comprehension question. The student is able to correctly answer the question after only the first level prompt.
Most to least prompting (i.e., system of most prompts, most intrusive prompt system) also uses a hierarchy of prompts like system of least prompts, but in this case, the prompting starts with the most intrusive prompt and systematically moves to less intrusive prompts as the student starts to respond more independently. Another major difference between the two prompt systems is that in most to least prompt system the instructor may stay at one prompt level (e.g., model prompt) for several instructional sessions before moving to a less intrusive prompt.
Because this system is not “self fading,” instructors should use daily data to guide these decisions. For example, once a student responds consistently with a model prompt, the teacher would then fade back to a verbal prompt. According to researchers (Spooner, Browder, & Mims, in press; Wolery & Gast, 1984), most to least prompting is the most widely used instructional procedure to teach response chains to individuals with developmental disabilities.
Graduated guidance is a response prompting system that is often associated with responses that require a motor movement (e.g., feeding, toileting). Graduated guidance was initially used to teach independent toileting skills to institutionalized adults with severe intellectual disabilities. The procedure involves the most intrusive prompt, typically hand over hand assistance or what is called a full physical prompt (e.g., hand over hand assistance to help a student scoop food and bring to mouth) until the instructor feels the student starting to participate. At this point the instructor will back off the amount of assistance (e.g., the instructor will move their hand back to the students wrist and continue to help the student scoop and bring food to mouth) until the instructor feels the student is starting to participate more or initiate movement. As training continues and student progress is being reflected, the instructor can continue to lessen the level and amount of the prompt (e.g., the instructor will move hand to the students elbow). This procedure continues until the teacher has faded assistance back to just shadowing the student. At any time during this procedure that the instructor feels the student not initiating or participating, the amount of assistance can increase again.
Stimulus prompting strategies, like response prompting strategies, can be used to change a target behavior. This procedure involves manipulating or changing the stimulus that is presented. There are two different antecedent prompting procedures commonly used, stimulus shaping and fading.
Stimulus shaping is the process of highlighting an important feature of the materials used for instruction, the relevant dimensions (Etzel & LeBlanc,1979; Spooner, Browder, & Mims, in press; Wolery & Gast,1984).
For example, to teach Sam to recognize his name, the teacher might begin by pairing the word “Sam” with shapes so that the difference is easy to discriminate. In subsequent trials, letters and words will be introduced until Sam needs to recognize all the letters in his name.
|Example of Stimulus Shaping|
*** Sam ***
Sam *** ***
*** *** Sam
Sam T a
M Sam x
S b Sam
put sit Sam
Ask Sam did
Bob dog Sam
Sam Sue Am
Sat Sam Mam
Tam Sue Sam
Here are a couple more examples of stimulus shaping.
Stimulus fading is the procedure where a feature of the materials (stimulus) is made more salient and then gradually faded over time to become a more generalized stimulus. In this procedure, fading involves the manipulation of any dimension of the stimulus (e.g., color, size, shape, position) not just the relevant one. This strategy is one of the oldest methods for teaching individuals with developmental disabilities to read sight words. Often the sight word will be paired with a picture or a relevant feature (e.g., the word red is written in the color red and eventually faded so the word red appears in black; the word car is written with a picture of a car behind the word, over time the picture of car is faded from the material and only the word car remains).
The following shows an example of stimulus fading for teaching the number 5 by manipulating size. The teacher might use several trials at each fade level.
At times teachers may become confused over prompts. For example, when giving a task direction, this is not a prompt. For example, “Read the word” and presenting a sight word is not a verbal prompt; rather it is the cue to respond. If you repeat the phrase again and pair it with the answer, it then does become a verbal prompt. For example, “Read the word, ‘car’”. This then becomes a verbal prompt. Additionally, supporting the student to get ready to respond is not a prompt unless you clue them into the correct answer. For example, placing a student’s hand above all answers so they can slide their hand to the correct answer is not a physical prompt. They still have an equal chance of getting the answer right or wrong. It is just positioning them in a ready position to respond. This may be used when students have limited physical abilities that may impede in his or her ability to correctly answer a question or respond to a stimulus.Principle of Parsimony
The principle of parsimony is to use the most efficient or simplest intervention method that is effective. For example, it is much easier for instructors to use response prompts rather than manipulating the stimulus itself (e.g., making materials that show a picture of a sight word slowly fading out is much more time consuming than just inserting a prompt after the presentation of the stimulus.) For this reason, teachers will typically try response prompts before stimulus prompts. In addition, some response prompting strategies are more parsimonious than others. For example, constant time delay may be easier for a paraprofessional or peer tutor to use than progressive time delay because there is only one level of fading. The following table provides a summary of the decisions teachers need to make in planning systematic prompting (Spooner, Browder, & Mims, in press).
|Decision||Least Intrusive Prompting||Time Delay of a Response Prompt||Most to Least Prompting||Stimulus Prompts|
|Will more than one prompt be used?||Yes||Probably not||Yes||No|
|What types of prompts will be used?||A hierarchy from less to more assistance (e.g., verbal, model, physical)||One prompt that is effective for student and target response (e.g., model)||A hierarchy of prompts from more to less assistance (e.g., physical, partial physical, gesture)||Some modification of the discriminative stimulus (e.g., color coding; use of picture)|
|How much time will I wait between the discriminative stimulus and the first prompt?||Wait about 3 seconds; then if no response, verbal; wait 3 more seconds, if no response, give model; wait 3 more seconds, if no response, give physical guidance.||On the first trial there is no time (zero delay) because prompt is given with the discriminative stimulus.||Wait about 3 seconds for student to respond, then use physical guidance. After a set number of days, fade to partial physical guidance.||Stimulus prompt is used concurrent with discriminative stimulus. Usually this requires some modification of materials in advance of teaching.|
|How will I fade the prompt?||This method is “self fading.” The teacher reinforces responses with least assistance student needs (e.g., if can do it with model, does not praise physical guidance).||The prompt is faded using increments of time. After the zero trials, the teacher uses some delay (e.g., 4 seconds). If progressive delay is chosen, this may increase across trials (e.g., 2’, 4’, 6’, 8’).||The prompt is faded by following a schedule to move to the lesser prompt (e.g., 2 days at each prompt level).||The prompt may be faded by reducing its salience (stimulus fading). In stimulus shaping, the discrimination is made more difficult on subsequent trials. Note: time delay can also be used e.g., The picture can be introduced after 4 seconds delay).|
|What do I do to discourage errors?||If an error begins, try to block it and give the next level of prompt. Praise correct responses.||Tell student “not to guess.” Repeat zero delay trials. If an error occurs after the prompt, a different type of prompt may be needed or change in reinforcement for correct responses.||If an error occurs after moving to a less intrusive prompt, block the error and give a more intrusive prompt (e.g., if an error occurs on the physical assistance level, give full physical).||No error should occur at first. If they do, the choice of stimulus prompt may need to be changed or some pretraining may be needed (e.g., to name the pictures). On subsequent trials, go back to the easier trials if errors occur (e.g., to less faded picture or easier discrimination).|
|How do I promote independence (transfer of stimulus control)?||Reinforce when student performs step correctly with less assistance. Give strong praise or other reinforce for unprompted responses.||Only praise correct responses. As begins to anticipate correct responses, only praise unprompted corrects.||Praise correct prompted performance until the last level of fading. Then only praise correct unprompted responses.||Praise correct responses. As fading progresses, only praise responding at levels equal to or better than, prior day.|
Spooner, F., Browder, D., & Mims, P. (in press). Chapter four: Using evidence-based instructional strategies. In D. Browder, & F. Spooner (Eds.). Curriculum and instruction for students with moderate and severe disabilities: Finding the balance. New York: NY, Guilford Press. Reprinted with permission of The Guilford Press.Teaching versus Testing
Using response and stimulus prompting procedures are great strategies to help your student learn, but to check for learning you need to look for student achievement through testing or probe sessions. This will provide you with information on what has been learned and what needs more teaching. To check for student achievement the student should have an equal chance of getting the item right or wrong.
Here are some examples of student achievement. The student selects the picture for main idea by either eye gazing, pointing, grabbing the correct answer, or pulling off velcroed responses to hand the answer to the teacher. For the goal of having a student label parts of a cell, the student can indicate the correct answer or show achievement by eye gazing, pointing, grabbing the correct answer, or pulling off velcroed responses to hand the answer to the teacher. So what is “something else?” Here are some examples of not showing achievement or mastery. Having the student select the correct picture for main idea after a model prompt does not show achievement. So when the teacher says, “Point where I point”, this is a great teaching strategy but should be faded out over time versus used constantly. By the time the student is tested on what they know, this prompt should be faded. Another example of “something else” is when the student works with a peer who selects the answer for the student. Again, this is a great strategy, but this support should be faded out over time to really identify what the student has learned. In the final example, the teacher places the student’s hand on a voice output device that says, “that’s the answer.” This does not show that the student knows the information on his own. Again, this is a great strategy, but it needs to be faded because the student is completely passive and you cannot determine if the student has really learned or not. When using a systematic prompting strategy, reinforcement and error correction procedures need to be considered. When reinforcing a student, only praise or deliver the reinforcer for making a correct response with no more assistance than needed on prior tasks. For example, if a student can make the correct response after only a verbal prompts, avoid praising the student if they respond after a model prompt. When correcting an error, if using the time delay strategy, small increments of time are used to discourage errors. If an error occurs, correct them and remind the student to wait if they don’t know the answer. When correcting errors during a prompt hierarchy like system of least prompts, or most to least prompts, you can either correct the error by providing the correct response and ending that particular teaching trial or you can deliver the next level prompt and continue through the prompt hierarchy. Finally, when using prompting strategies, two important points must be considered: reinforcement and error correction procedures.