Negative reinforcement is not exactly the opposite of positive reinforcement as one would expect. This strategy in the treatment of autism and related pervasive developmental disorders uses undesired objects or activities as a shaping tool for behavior. Basically, the objectionable object is removed or the child no longer has to engage in the undesirable activity. For example, a therapist is working with an autistic child with the specific goal of teaching him to sign “all done.” This student hates coloring. The approach of using negative reinforcement would use coloring as a tool for learning. The child is introduced to the task that he dislikes and the therapist prompts him to sign “all done” and once the child does the task is quickly taken away. In this example the target is not the activity of coloring. The target is the communication sign “all done.” The task of coloring is used as negative reinforcement in order to motivate the child to indicate that he no longer wants to participate in the activity.