Receptive Identification of Objects

Receptive Identification of Objects

The Receptive Identification of Objects Program is designed to teach the student to identify objects and persons encountered in her everyday life. This is a skill that may be taught regardless of whether the student possesses expressive language skills. The teacher's familiarity with the procedures presented in this chapter and the student's success at learning to receptively identify objects may help the student acquire new concepts such as colour, shape, and size (see Chapter 25). Prior to starting this program, the student should have been working on the Matching and Sorting, Nonverbal Imitation, and Early Receptive Language Programs (Chapters 12, 13, and 15, respectively), with the beginning stages at or near mastery. Further, it is essential that the teacher be familiar with discrimination learning procedures (see Chapter 16).

To teach the student to receptively identify objects, the teacher needs a large number of common household objects (e.g., cup, shoe, block, cookie, crayon) with which the student has frequent contact, photos of these same household objects, photos of the student's parents and siblings, pictures of objects cut from magazines or other sources and mounted onto 3 x 5-inch index cards, and a table for placement of the objects and pictures. To help ensure that the student can tell the objects and the pictures apart (i.e., discriminate among the 3-D objects and the objects depicted in the pictures), it is helpful for the student to have mastered matching of the stimuli to be employed in this program (see Chapter 12).

We present this program in considerable procedural detail to facilitate the teacher's learning of correct treatment techniques. Obviously, the better the teaching techniques, the more rapidly the student will acquire the skills taught. As the teacher gains experience, future programs will be presented in a less detailed, step-by-step format.

Identifying the First Two Objects

The first two objects the student is taught to identify should be ones the student frequently encounters in his everyday environment and ones that are easily held by the student. We illustrate the procedures for teaching the student to identify the first two objects by using a cup and a shoe. It is important to choose objects with minimally distracting features; thus, in our example, small, solid-coloured objects without pictures or designs are used. Other objects the teacher could use include a toy truck, a plain doll, a solid-coloured ball, or a food item such as a cookie or an apple.

If the student can identify a particular object (e.g., by touching it, pointing to it, or going to get it when asked to do so) before he receives any formal instruction, begin teaching with that object. We recommend first establishing instructional control over the objects the student can already identify so that the student's success can be maximized and teaching time can be minimized. In addition, if the student already knows how to identify one or a few objects but often fails to demonstrate this skill when requested to do so, the task now is to obtain more consistency.

► Step 1

Place the cup about 1 foot in front of the student and on the table and concurrently say, 'Cup.' Enunciate the word 'cup' in a succinct and clearly audible manner. The presentation of the cup and your verbalization of 'cup' constitute SD1. If the student fails to respond correctly, repeat the instruction and, immediately after presenting SD1, physically prompt the student's response by gently taking his hand and placing his palm on the cup. (Touching the appropriate object is illustrated in these steps as the correct response. The student may be taught, however, to point to the correct object on the table or hand you the correct object.) If the student has made sufficient progress in nonverbal imitation, simply model the correct response (a less intrusive prompt) while giving the SD. If the prompt is not performed concurrent with or immediately after the SD, the time interval between the SD and the correct response will be too long to form the SD1-R1 association.

Reinforce the student immediately after he performs the prompted response. Next, remove the cup from the table, replace it on the table, and say, 'Cup.' This starts a new trial, and the removal and replacement of the cup ensures a discrete and succinct stimulus presentation, facilitating the student's attention to the stimulus. Keep the interval between trials at 1 to 3 seconds. After 3 to 4 successful prompted trials, gradually and systematically fade the prompt in subsequent trials by, for example, performing less and less of the model or pulling more and more lightly on the student's hand and releasing his hand sooner and sooner before it reaches the cup. Next, slowly transfer from a manual or model prompt to a less intrusive prompt such as pointing to the cup. Then fade this prompt as well. Reinforce each correct response whether or not it is prompted, but maximize reinforcement for unprompted trials. When the student responds correctly without prompting in 5 out of 5 or 9 out of 10 trials, proceed as described below.

Continue to present mass trials of SD1, repeatedly presenting the same SD in each trial. Introduce a slightly more difficult component by placing the cup in a different location on the table on each trial. Vary the position of the cup in relation to the student so that the cup is placed on the left side of the table on one trial, the right side of the table on another trial, and so forth. This step is introduced to help avoid position cues and facilitate the student's scanning for the object. After 3 to 4 unprompted correct responses in a row, go on to Step 2.

Keep in mind that at this point the student has yet to learn to identify a cup as a cup. The student might touch any object when instructed, 'Cup.' The steps that follow are introduced to help the student discriminate (attend to the differences) among objects. To facilitate this discrimination, the second object taught to the student should look different from the first object taught and it should have a name that sounds different from the label of the first object. For example, a glass would not be an ideal second object to use because it looks similar to a cup. Likewise, a cat would not be ideal as a second object because its label sounds similar to the word cup. A shoe may be a good second object to teach because it looks different from a cup and its label sounds different as well.

► Step 2

Clear the table of all stimuli. Present SD2 by placing the shoe on the table in front of the student and concurrently stating, 'Shoe.' Prompt the student to respond correctly (i.e., touch the shoe) by guiding his hand on top of the shoe or by modelling the behaviour. Reinforce. Remove the shoe between trials to make its presentation discrete. Continue to present SD2 ('Shoe') in mass trials, gradually fading the prompt over subsequent trials. When the student successfully responds without prompting in 5 out of 5 or 9 out of 10 trials, continue to present mass trials of SD2 ('Shoe'), placing the shoe in a different location on the table at the start of each trial to avoid position cues and facilitate scanning. When the student is successful without prompting in 5 out of 5 or 9 out of 10 trials, go on to Step 3.

► Step 3

Intermix SD1 ('Cup') and SD2 ('Shoe') according to discrimination learning procedures. Present SD1 with a full position prompt by placing the cup in the middle of the table and the shoe in the back comer of the table away from the student. The placement of the cup close to the student facilitates the correct response (touching the cup), whereas the placement of the shoe away from the student helps to inhibit the student's touching the shoe. If the student fails to respond correctly, repeat SD1 ('Cup') and further prompt the next trial by physically guiding the student, pointing to the cup, or modeling the response. Fade the physical, point, or model prompt first, and then fade the position prompt over subsequent trials by reducing the distance between the two objects until they are aligned on the table and about a foot apart, equidistant from the student. Remember to randomly rotate the leftright positions of the objects (cup and shoe) on the table throughout this step to help avoid inadvertent cues. When the student responds correctly without prompting in 9 out of 10 or 19 out of 20 consecutive trials, go on to Step 4.

► Step 4

Present SD2 ('Shoe') with the shoe placed in front of the student and employ a full position prompt by placing the cup on the back comer of the table. Present mass trials of SD2 ('Shoe'). Fade the position prompt over trials until the cup and shoe are placed linearly, about 1 foot apart and equidistant from the student. Remember to randomly rotate the left-right positions of the objects (cup and shoe) on the table throughout this step to help avoid inadvertent cues. Set mastery at 9 out of 10 or 19 out of 20 unprompted correct responses.

► Step 5

Reintroduce SD1 ('Cup') using a full position prompt. Fade the position prompt while reinforcing correct responding. Because the SD1-R1 relationship has been strengthened, the prompt can be faded more quickly; that is, the two objects can be brought closer together more quickly without causing errors. If errors do occur, reintroduce the least amount of position prompt necessary to occasion correct responding. Place mastery at 5 out of 5 or 9 out of 10 unprompted correct responses. (With each reversal of SD1 and SD2, a lesser number of correct responses are necessary.)

► Step 6

Switch back to mass trials of SD2 ('Shoe'). Start with a full position prompt, and then fade the prompt over subsequent trials. When the student independently responds correctly in 4 consecutive trials, go on to Step 7.

► Step 7

Return to mass trials of SD1 ('Cup'). Begin with a reduced position prompt: Place the cup in the middle of the table and the shoe halfway between the back comer of the table and the cup. Fade the position prompt over subsequent trials. When the student independently responds correctly in 4 consecutive trials, go on to Step 8.

► Step 8

With the cup and shoe on the table, begin alternating between SD1 and SD2, gradually lessening the number of consecutive correct responses needed before switching SDs. If the student responds incorrectly on any given trial, reintroduce the least amount of prompting that reinstates the correct response. Fade all prompts completely before switching to the alternate SD, giving maximal reinforcement for unprompted trials. When the student responds correctly to each SD when directly contrasted (i.e., SD1, SD2, SD1, SD2, etc.), begin random rotation of SD1 and SD2 as described in the discrimination learning chapter (Chapter 16). Place mastery at 9 out of 10 or 19 out of 20 unprompted correct responses with the SDs randomly rotated.

Because the first discrimination is the most difficult one for the student to master as well as an important achievement, it is recommended that this discrimination be generalized in blocks of 5 to 10 trials across teachers and environments 4 to 5 times per day over the next 3 to 4 days before teaching identification of additional objects. Distributing practice of the discrimination across various times of the day will also help the student remember (retain) what has been learned.

In introducing new persons and environments, be aware that it may take weeks for some students to master the transfer of newly acquired skills. The reasons why some students experience this lag are difficult to ascertain. Perhaps moving from a highly controlled environment into one with several distracting stimuli contributes to the problem. In any case, generalize skills in a careful and systematic manner. For example, in generalizing environments, move slowly and in a stepwise fashion from the treatment room to the door, then to the hallway, and then to other rooms.

Identifying the Third Object

Teach the student to identify a third object by following the steps in the previous section. Make sure this object is perceptually different from the first two objects. After the student masters identifying the third object when presented in mass trials, teach the student to discriminate between SD3 and SD1 and then SD3 and SD2. Then teach the student to discriminate between all three SD, subjecting them to random rotation.

Identifying Additional Objects

Once the student is able to identify and discriminate among three objects, teach identification of additional objects by following the same procedures used to teach the first three.

That is, teach each new object to mastery one at a time, and then intermix the objects to establish discriminations among them. Initially the objects selected should be common items the student encounters in her everyday environment, and they should be chosen carefully to avoid similarities in appearance and sound of the labels. As the student gains experience in the program, however, items that look and sound more similar should gradually be introduced.

As the student learns to identify a larger number of objects, you may find that it is not necessary to follow all of the steps listed in the standard discrimination learning procedures to establish mastery. Mastery of the identification of earlier objects may enable some students to discriminate between a new object and any mastered object without having to employ an elaborate intermixing of objects and prompting techniques for each new SD.

Areas of Difficulty

If the objects chosen to teach are too similar in appearance or their labels are too similar in sound, the student may have difficulty making the discrimination. Keep in mind that two object labels may sound quite different to you but very similar to the student. For example, the words sock and book are different in terms of initial sounds and vowel sounds. However, their final sounds (k) are identical. If the student retains only the final sounds of words in his memory (which also are the most recent sounds), the student will have difficulty learning to discriminate between these objects despite their different appearances.

Inattention is also very likely to lead to difficulty making discriminations. Several factors may contribute to the student's inattention. As mentioned in Chapters 6 and 8, a student may not attend to the task at hand because of his engaging in self-stimulatory behaviour, which competes with reinforcers the teacher offers. Inattentive behaviour may also result if a teacher presents too many trials in a single sitting and the student resorts to inattentive behaviour to avoid or escape the teaching situation. During the beginning stages of teaching, try to limit the number of trials to 5 or so in a single sitting, reinforcing the student by ending the sitting and engaging in a short break. Also, try to quickly intersperse 3 to 4 trials of already mastered material, such as nonverbal imitation. Such trials may serve as wake-up exercises and help motivate the student to continue with the more difficult task. Another factor that may contribute to a student's inattention is a slow pacing of trials. Long inter-trial intervals allow the student to engage in alternative behaviours between trials and lose focus on the task being taught. In contrast, short inter-trial intervals may block self-stimulatory behaviour and reinforce attending to the teacher.

The student may have difficulty discriminating between objects because the presentation of materials is not optimal. The procedure of displaying objects on a table requires the student to attend to the table and scan the objects to make a correct response. Some students have greater success when objects are held in front of them by the teacher at eye level. However, there are drawbacks to using this approach. One drawback is that this method of presentation automatically imposes a limit on the number of objects able to be presented at one time (one object per hand). A second drawback is that this method of presentation differs from the standard procedure used in schools and many other environments. The differences in procedures could result in reduced generalization across environments. Given these drawbacks, presenting the objects by holding them should be considered a type of prompt that must be faded over time until the objects are displayed on the table.

Again, keep in mind the different rates of learning among students within the same diagnostic category. Some students learn the first discrimination within 10 minutes and acquire identification of new objects at the extremely rapid rate of one per minute if the teacher so allows. Be careful not to proceed too fast, because such a student can easily be overloaded with labels and is likely to become noncompliant. Remember that students with developmental delays often do not possess the verbal skills necessary to inform the teacher when tasks become overly abundant or too complex. If the student learns five new labels per week and makes steady progress in other programs, consider the acquisition of 40 receptive labels in a 2-month period to be sufficient. There is much more for the student to learn than identifying objects.

On the other extreme, there are students who experience difficulty mastering the first discrimination after 1 month of teaching. If the student you work with demonstrates such difficulty, consider the following: (a) the student may acquire receptive identification of actions more easily than receptive identification of objects. If so, the identification of objects may be prompted by including receptive action labels in the SD (e.g., 'Push car,' 'Drink juice,' 'Eat cookie,' 'Wipe mouth'). The action labels (push, drink, eat, wipe) may then be faded until only the object labels (car, juice, cookie, mouth) remain. Such a pre-training step may help the student discriminate (attend to) the object, (b) It is a good idea in the beginning of this program to make certain the student can tell apart the objects to be taught. Demonstration of this skill may be observed through the mastery of matching pairs of these objects (see Chapter 12). (c) Some students acquire expressive labelling of objects (see Chapter 23) before they acquire receptive identification of objects (Smith, 1999; Wynn, 1996). That is, some students learn to verbally label objects by, for example, saying 'Cup' to the sight of a cup and 'Shoe' to the sight of a shoe but have serious difficulty identifying these objects when asked to do so receptively. If this is the case for the student you work with, begin teaching where the student's strength lies. After mastering a skill by one mode, the gains acquired may transfer in part to another mode.

For those students who experience extreme difficulty making the first SD1-SD2 discrimination, there exists a remedial or pre-training step whereby SD1 is first discriminated from what we have labelled a contrasting stimulus instead of SD2. A contrasting stimulus can be any mastered stimulus that is maximally different from SD1. Intermix SD1 with the contrasting stimulus as suggested in the discrimination learning chapter (Chapter 16). In brief, the sequence of trials may proceed by first intermixing SD1 with a nonverbal imitation task. Chances are that the student will make few errors, if any. Next, proceed to a more difficult step in which SD1 is contrasted with your verbal SD for a mastered action such as 'Stand up.' Because your SD is verbal, the student is likely to make mistakes but may well acquire the discrimination sooner when presented in this manner than when presented as the original discrimination between SD1 ('Cup') and SD2 ('Shoe'). The purpose of using a contrasting stimulus is to make the steps toward reaching the target discrimination more gradual and successful for the student.

If the student encounters serious difficulty in acquiring receptive identification of objects despite the recommendations described in this section, we suggest placing this program on hold for a month or two. In the meantime, practice other programs and reintroduce the Receptive Labelling of Objects Program at a later stage in treatment.

Anticipate the fact that students often become frustrated and bored when subjected to a strict teaching criterion of success such as 19 correct out of 20 unprompted trials. On one hand, you want to be certain that the student masters the discrimination, which shows that the student is learning to concentrate on the task and suppress attention to interfering stimuli (e.g., self-stimulatory behaviours). On the other hand, you want the student to enjoy being taught. This situation underscores the need to be creative in finding novel and powerful reinforcers to accompany teaching sessions.

In short, there is considerable room for experimentation in the area of teaching students with developmental delays. When you reach a stumbling block, take this to mean that more must be learned about individual differences and the development of innovative methods of teaching. This is only one example of when an experienced consultant can be a great deal of help and when it pays to work within a team.

Generalizing Receptive Identification of Objects

After the student learns to identify approximately 15 different objects, begin generalization across objects of the same class. Generalization helps programs become more functional and help ensure that the student is not solving discriminations by attending to some irrelevant feature of the stimuli. Through generalization, the student learns to identify many different examples of an object belonging to a class of objects, not only the single item initially taught. For example, after the student learns to identify a particular kind of a shoe, she should be taught to identify sneakers, high heels, sandals, and loafers as shoes. Teach new exemplars of mastered objects by varying their shape, size, and colour (Stokes & Baer, 1977).

Initially, generalization should be limited to items that look quite similar to the original object to maximize the student's success. As the student progresses, gradually introduce items that look increasingly dissimilar from the original object. When introducing a new example of a mastered object, the student may need prompting. Continue to teach members of a class until the student can identify several new members the first time they are presented. After the student can correctly identify a member of a class on the first trial, the student is closer to forming a concept of that class. One assessment of the extent to which a student can identify members of a class is provided in the Matching and Sorting Program (see 'Category Matching' in Chapter 12).

After the student masters identifying classes of objects in the highly structured table setting, begin teaching the student to identify objects as they occur in her everyday environment. In preparation for such generalization, teach the student the receptive instruction, 'Get (object).' To facilitate acquisition of this task, start by placing a familiar object, such as a shoe, on the table in front of the student as was done earlier in the program. Present the instruction, 'Get shoe' (emphasize the word 'Shoe' initially), and, if necessary, prompt the student to pick up the shoe and hand it to you. Present mass trials of this SD, fading the prompt over subsequent trials. After 9 out of 10 unprompted correct responses, probe a different familiar object, such as a cup. Present the instruction 'Get cup' and wait to see if the student responds correctly on herself. If the student fails, prompt and reinforce on the next trial. Fade the prompt over subsequent trials and practice this SD until mastery is reached.

Once the student shows mastery of this discrimination, place the objects farther and farther away from the table on subsequent trials and eventually require the student to leave the chair to retrieve the specified item. In gradual steps, teach the student to recover objects from the other side of the room, the hallway leading to a second room, and finally from another room.

After the student learns to recover objects one at a time from several different locations, return to the original teaching environment (at the student's table) and place other objects near the target item to increase the complexity of the task. Once this skill is mastered, ask for more than one item at a time. For example, present the instruction 'Get shoes and socks.' When introducing this step, it is helpful to place objects close to the table, thus reducing the length of time the student must keep the two items in memory before retrieving them. (Please read 'Two-Part Instructions' in Chapter 15 for ideas on prompting this skill.) The goal is to increase both the number of items the student must retrieve at one time and the distance of the objects from the student.

Identifying Pictures

Once the student can easily identify a variety of objects of different classes in three-dimensional (3-D) form, teach the student to identify these objects in two-dimensional (2-D) picture form. To teach objects and persons depicted in 2-D form, follow the same procedures used to teach 3-D objects. You may want to buy stimuli by purchasing appropriate flash cards through a store that sells learning materials, or you can create the stimuli yourself by cutting out pictures from magazines and gluing them onto index cards or by taking photos of objects.

Use pictures of objects that are commonly found in the student's environment. Pictures of individual family members and friends may be introduced as well. The pictures used should be free from background clutter, roughly the same size, and mounted on same-sized cards (e.g., 3x5 inches). If pictures or cards of different sizes and shapes are used, the student may attend only to this size-shape dimension when discriminating among the stimuli. If the pictures have items in the background, the student may attend to these items rather than to the target objects.

Remember, what the student attends to is not always what the teacher intends for him to attend to. Therefore, after the student masters identifying approximately 15 objects in 2-D picture form, introduce pictures of different exemplars of class members to promote generalization. Do so by following the same procedures described for teaching generalization of 3-D objects.

Areas of Difficulty

If the student has difficulty identifying objects in 2-D form, it may be helpful to introduce photos of mastered 3-D objects before other pictures are introduced. If the student continues to have difficulty with the photos, try presenting the pictures vertically (as on an easel) rather than horizontally (flat) on the table so that the cards are presented closer to the student's eye level. Over time, fade the use of the vertical display.

If the student has difficulty mastering receptive identification of pictures but not objects, use the object as a prompt by placing it behind the picture. Fade the use of the object by gradually covering it with a piece of paper and then eventually removing it completely. In the reverse case, if the student has difficulty mastering receptive identification of objects but not pictures, place the object directly behind the picture and then gradually fade the picture by covering it more and more with either the object itself or an index card.

Concluding Comments

There are three major benefits to learning the skills described in the Receptive Identification of Objects Program. First, by progressing through the program, the student becomes increasingly attentive to her environment. This attention successfully competes with, and may over time replace, excessive self-stimulatory behaviour. Second, the student gains increased skill in memory. The longer the instructions and the greater the physical distance between the student and the objects, the longer the student must memorize ('store') your instruction. In conjunction with increased memory, the student is taught generalization of the object identification task across environments. Third, instead of the teacher manually guiding the student to a particular object, the adult can increasingly manage the student on a verbal level. For example, the student's mother can ask the student to bring her a pair of the student's shoes from the bedroom rather than physically guiding the student to do so or having to do the task herself. The longer this skill is practiced the more benefit you and the student are likely to receive. Through mastery of this program, the student should become increasingly easy to manage and live with, a desirable outcome that was initiated in the first hours of treatment (Chapter 9).