Shaping

Technical Description

Shaping involves differentially reinforcing responses that successively approximate a terminal response class resulting in new and/or more complex and elaborated behaviors. The basic behavioral principles operating in shaping are reinforcement and extinction, which when used in combination, such that only a certain class of responses is reinforced while others are not, is referred to as differential reinforcement. For example, when coloring with crayons, children must acquire responses of adequate force to produce marks on paper. One set of responses, those involving sufficient force to produce color, is reinforced, while responses of insufficient force produce no reinforcement.

In differential reinforcement, the response requirement for reinforcement is generally relatively stable. For instance, a certain class of forces, once established, will almost always produce color on paper. How, though, is the response class established? Here is where shaping enters the picture. Shaping involves a sequence of differential reinforcements where the provision of, or the amount of, reinforcement is linked to the progression of responding. As performances that more and more closely resemble the ultimate performance are established, previous steps in the sequence no longer produce reinforcement (or produce less reinforcement than current and subsequent steps). To illustrate, imagine teaching a child who failed to learn to color. First, the child might be reinforced with food for holding or grasping a crayon. Then, holding the crayon with the tip touching the paper would be required for reinforcement. Next, some small movement of the crayon on the paper with enough force to produce faint color would be required. Finally, only movements of the crayon that produced solid color would be reinforced. Notice in the coloring example the interaction between an arbitrary reinforcer and a naturally occurring reinforcer. Early responses in the sequence were reinforced by food; however, as shaping progressed, the natural contingency between using adequate force and seeing color on the paper could also begin to reinforce appropriate responding along the force dimension. That is, too much force would result in the crayon breaking, too little force would produce no, or only faint, color, while a range of forces produced the clear sight of color.

It is important to note that shaping is involved in the acquisition of many responses but is often not [Page 1032]recognized as such because it is occurring naturally or in the context of the child's interaction with a social environment that is effective in intuitively shaping behavior. For instance, when a child first responds to the letter W by saying “double cue,” caretakers may provide praise but later will require the child to more closely approximate “double you” before praise is given. When the child begins to string letters together and first utters “a-b-c-d-e-c-d-e,” the parents may praise the partially correct response. However, soon such praise will be reserved for only more extended correct utterances. The programmed use of shaping in clinical settings is simply a formal extension of the process that is occurring in a less formal, but no less influential, manner across many domains during development.

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