Mands for Missing Items


Pre-requisite mand skills: Student should have an established repertoire of a variety of mands with item present as well as mands for actions and be able to mand across instructors and settings.


Pre-requisite skills from other strands: Familiarity with tacting items and actions used in various activities.


Motivative Operations: Mands for missing items necessarily involve transitive motivative operations; the motivation for a specific reinforcer temporarily establishes the value of something else as reinforcing that the student will be likely to mand for.


In order to teach mands for missing items the instructors will have to identify items and activities that are reinforcing to the student and then establish motivation for something else that the student will need to obtain the item or to complete a desired activity. For example, if a student likes to eat peanut butter sandwiches and has previously learned to mand for the plate, bread, peanut butter and the knife while items are present to make the sandwich, and the instructor knows that the student wants to make a peanut butter sandwich; then the instructor can have all the items out except for the knife (which will be valuable now because the student is motivated to make the peanut butter sandwich). When it is time to use the knife and the instructor confirms motivation for the missing knife (student is looking for knife in front of him which is where it is typically located), then the teacher can prompt the mand for knife.)


Evocative effect considerations: what topographies will need to be shaped; which topographies will need to be extinguished:


Instructors will need to be sure that completing the task is valuable to the extent that if some component of the task is not present, it will evoke behaviors from the student that serve to get the missing item.


Target response definition: Keep in mind that initially, the activities and/or items selected as targets are those that involve items and activities that are highly motivating to the student. In other words the targeted mands will be necessary to obtain items or complete activities that are valuable to the student. However, in order to expand the repertoire of mands for missing items, we will also need to teach students how to mand for items needed to complete tasks that may not be reinforcing in and of themselves. In this case, the completion of the task, and not necessarily the task itself, will need to serve as a reinforcer to the student. In other words the targeted mands will be mands for items necessary to complete non-reinforcing activities, but the completion of that activity has reinforcing value to the student. An example of this may be completing a homework assignment that is not motivating in and of itself (but being done with it is surely a good thing!) Having to do the homework will establish all things necessary for the task as reinforcers (workbook, pencils, etc.)


Response topographies targeted for extinction: Instructors will need to make sure that error responses do not contact reinforcement. This would include the student asking for an item that is already in their possession. For example, it might be the case that for some students the instructor’s attention is valuable and they learn that “manding for missing items” results in obtaining the instructor’s attention. The student may then use the topographies being targeted for missing items when they are motivated for the instructor’s attention or interaction and not necessarily when they want or need a missing item. In these cases the instructors will need to make sure these responses do not contact reinforcement.


Teaching Procedures: Set up the situations that will establish the value of another item as a reinforcer because of it being necessary to obtain the end reinforcer. Of course, you will need to ensure that the missing item is not visible.


Prompting and prompt fading:

  • Once the transitive motivative operation is in effect, the mand can be prompted with the least intrusive prompt that will evoke the correct response. Some cases will require a combination of prompts (i.e., showing the item and saying the name of the item).
  • Prompts are faded through the use of time delay procedures and or by gradually fading the item (showing less of the item) and the mand form (using partial prompts).

Fading to MO control: Ultimately the goal is to fade prompts so that the only source of control is the transitive motivative operation (the motivation for an item because it is needed to obtain an item or complete an activity).


Other Procedural considerations:


The following is a sample chart (Adapted from Dr. Vince Carbone) that can be helpful in planning and collecting data for the mand sessions:


Chart 15

What is already reinforcing to the student?What do I need to do to establish the value of something else as reinforcing?What now becomes valuable as a reinforcer?What response do I need to prompt?Data Collection: Record P for prompted and U for unprompted
Eating ice creamGive student the ice cream with no spoonA spoonShow spoon and say "spoon" 
Blowing bubblesGive student the bubbles without the wandThe wandShow wand and say "wand" 
Completing work to get praise from teacherAsk student to write the numbers 1-10 and give paper but no pencilA pencilShow pencil and say "pencil" 


Data Collection:

  • Cold probe of target mands for missing items
  • Tally of prompted vs. unprompted mands per session or per day.
  • Tally of untrained novel responses.

Graphing: Graph cumulative acquired targets for missing items as well as prompted vs. unprompted mands for missing items.


Data based decision making:


Careful analysis of data and student responding will be necessary to make decisions such as when and how to fade prompts.


Decisions regarding when to discontinue direct teaching of mands for information can be made when the student demonstrates the ability to mand for missing items in novel untrained situations, across settings, and instructors.