I've spent a lot of previous blogs talking about the importance of 1) using appropriate terminology, 2) describing procedures fairly and accurately, and 3) assessing research in light of a specific child's characteristics and the skill to teach. Let me put that into practice by debating, "Which is better: initially emphasizing requesting or labeling (i.e., mands or tacts) in ABA therapy for children with autism?"

Appropriate Terminology

Behavior analysts who have pushed for more use of verbal behavior terminology in behavioral treatment have done our field a service in helping all of us start with precise terminology. In laymen's terms, a mand is when a child requests for something and tacts are when a child labels something. In behavioral terminology, a mand is a verbal response that is controlled by an establishing operation. A tact is a verbal response that is controlled by a nonverbal discriminative stimulus such as an object or property of an object (see Peterson, 1978).

Describe Procedures Fairly And Accurately

My question focuses primarily on whether it is better to initially emphasize tacts or mands for children with autism. There are a number of different procedures used in the research to answer this question. As you will see, it is important to consider whether a procedure that is used leads to biased results. Also, since our ultimate goal is to teach children both tacts and mands, we shouldn't just be concerned with which procedure leads to faster acquisition. We should consider whether children learn both mands AND tacts more quickly by emphasizing mands or tacts first.

Assessing Research In Light Of A Specific Child's Characteristics
And The Skill You Would Like To Teach

Finally, the initial question, "Which is better..." is too simplistic. Research shows that different child characteristics and skill development issues should be taken into account when deciding whether to initially emphasize mands or tacts.

Here's some of the relevant research to answer the question.

Hall (1987) – demonstrated that teaching tacts does NOT lead to manding; 2 deaf children with mental disabilities and low rates of manding were involved in the study.

Arntzen (2002) – found that teaching tacts resulted in slower acquisition than alternating trials of tacts and mands. However, the tempo/rate of reinforcement was slowed down in the tact only condition to mirror that of the alternating tact-mand condition. While this controls for other variables in the study, it also biases the results because one of the practical strengths of teaching tacts is that you can typically provide reinforcement on a more frequent basis. Three children with autism were involved in the study using objects, pictures, or letters.

Wallace (2006) – found an important distinction in that high-preference items taught as tacts did quickly transfer to mands while low-preference items taught as tacts did not transfer to mands. Three adults with mental retardation who demonstrated low rates of manding were used in the study.

Kelly (2007) – found that for one child with autism, more responses initially taught as tacts transferred to mands (2 out 3) and less responses initially taught as mands transferred to tact responses (1 out of 5). Two other children with lesser disabilities (general language delays and apraxia) transferred the skill more easily, whether tacts or mands were taught first.

Based on this preliminary research, what kind of questions should we ask when deciding whether to emphasize mands or tacts in ABA Therapy? Here's what I think:

1. Does the child demonstrate low rates of manding?
   If yes, then placing an emphasis on mands makes sense. Actually learning to request is a skill that does not emerge on its own for children with autism, even if they learn the name of an object.
   If no, then placing an emphasis on tacts makes sense. Research shows children are more likely to generalize from tacts to mands (at least for highly preferred items...which is the point of mands) than from mands to tacts.
2. Does the child learn new labels quickly through mand training?
   If yes, then placing an emphasis on mands is an option.
   If no, then it may be helpful to give additional time to teaching labels as tacts. Teaching mands is limited by satiation effects (when a child is no longer interested in an item during a session) whereas tacts can be practiced more frequently with a variety of different reinforcers.
3. Are there a large number of mands to teach?
   If yes, then it may increase a child's acquisition rate to teach some as tacts, since again these are the items that are more likely to transfer to mands.
4. Are there mands that are difficult to practice due to time limitations or other factors?
   Some highly preferred objects or events can take up a lot of therapy time (e.g., teaching "outside"). Other highly preferred objects you may not want to give your child access to frequently enough to teach them as mands (e.g., the names of a variety of different candy or sugar snacks). And some children who have difficulty with vocal language may not easily tolerate attempts to shape the sounds they make while they are also requesting highly preferred objects. In all of these cases, tact training can help teach labels that research shows are more likely to then transfer to mands.

One of the important additions to behavioral treatment for children with autism has been a greater emphasis on teaching mands. However, at conferences and on the Internet, the question of teaching mands vs. tacts is simplified into a statement such as "research shows that teaching mands first is a more effective form of treatment than traditional ABA therapy." What I've learned at the Lovaas Institute is that true individualization of a child's program involves much more elaboration. It involves a close look at the research and attention to the 5 factors I just discussed in the blog on Creating the Best, Evidence-based ABA Therapy.

Any comments or other relevant research I should have considered?

Arntzen, E., & AlmÅs, I. K. (2002). Effects of mand-tact versus tact-only training on the acquisition of tacts. Journal of Applied Behavior Analysis, 35, 419-422.

Hall, G., and Sundberg, M. (1987). Teaching mands by manipulating conditioned establishing operations. The Analysis of Verbal Behavior, 5, 41-53.

Kelley, M. E., Shillingsburg, M. A., Castro, M. J., Addison, L. R. & LaRue, Jr. (2007). Further evaluation of emerging speech in children with develoopmental disabilities: Training verbal behavior. Journal of Applied Behavior Analysis, 40, 431-445.

Peterson, N. (1978). An Introduction to Verbal Behavior. Grand Rapids, MI: Behavior Associates.

Wallace, M., Iwata, B., & Hanley, G. (2006). Establishment of mands following tact training as a function of reinforcer strength. Journal of Applied Behavior Analysis, 39, 17-24.