Developing mand and tact repertoires in persons with severe developmental disabilities using graphic symbols.

An important educational objective for many persons with developmental disabilities is the acquisition of verbal operants such as the mand (e.g., requesting) and tact (e.g., labeling). Mands and tacts have been described as separate response classes and several studies support this description. Consequently, an important applied issue involves implementing procedures to develop both tact and mand repertoires. The present study investigated procedures for developing mands and tacts in three learners with severe disabilities. Learners were first taught to tact, then mand food/beverage items and the utensils required to access those items by pointing to line drawings depicting the items. The results suggest that responses acquired as tacts do not readily occur as mands. "Spontaneous" manding was developed through a transfer of stimulus control procedure which brought mands under the control of conditioned establishing operations. Substantial transfer to untrained objects and transfer across response classes were frequently noted after both tact and mand interventions had occurred for some items. Variables facilitating these generalized effects are discussed.