The Importance of Interspersing Mand Trials

Some students with autism may have very few items or activities that will serve as reinforcers. We have already discussed how to condition new reinforcers. The tendency, however, among instructors new to mand training may be to teach a student only one or two mands and not broaden the student’s range of mand behavior. In our work, we have noticed that a student who is taught only one mand will begin to use that single mand for multiple purposes. It becomes what is known as a generalized mand. For a well developed repertoire of mands to be established, students will need to learn to use many topographies to control asking for many items and events. At first, this means that students should be taught that one particular response topography controls one and only one reinforcer. During early mand training instructors should actively teach several mand responses correlated with several specific items. Care must be taken, however, to insure that the student is not presented with too many mands at once. Learning too many at one time can lead to frustration due to response discrimination demands. As a general rule of thumb, it is best to use at least two or more different reinforcers whenever possible during any mand training session. This will allow students to learn that each topography matches a specific reinforcer. The sign or vocal word for “candy” will result in getting candy and the sign or vocal word for “cracker” will result in getting cracker.

In mand sessions it is important to intersperse trials for different motivators to teach discrimination. For early learners other reinforcers may also have to be interspersed to help maintain interest and motivation. These items should be freely given without a mand response requirement. Teaching students to emit discriminated mands is a central objective of early mand training. In other words the student must learn to discriminate when to use what sign or vocal word.

Another reason for interspersing various mand trials in any one session is to maintain the value of the reinforcers. If only one preferred item is used to the exclusion of others, motivation for manding for the item may fade due to variables related to satiation or habituation.