Initially, they affirm that a critical difference between preschool children with autismo and children with normal development mentions the type to it of stiffener which they are responsive. That is, children with TEA normally do not answer stiffener the social ones, such as compliments and approval of the parents, professors, etc. Therefore, with the purpose to develop operative verbal as tatos, intraverbais or ecicos it is necessary that other stiffener educational not-social ones are used, is necessary that they are ' ' you reward tangveis' ' (P. 253), as candies or some another stiffener one more well-succeeded and established in the repertoire of the child. For this reason, the control is the first category of verbal behavior that is taught to a child with TEA in the PECS, therefore it involves stiffener that already they are effective and that they do not involve the verbal behavior of another person. The sequncia of training, presented sucintamente to follow, used for the PECS has the specific objective to promote spontaneous verbal behavior in children with TEA through the removal of previous a verbal behavior as control source (of this relation it would appear, then, the control-tato). For this, these pure and impure verbal sources of control for operative must meticulously be analyzed. Additionally, the authors place that, later to establish pure mandos, the stiffener object would be removed of sight so that the only source of control is a estabelecedora operation and the presence of the listener.

1.Fase I? Teaching the attended exchange physically: this phase starts teaching the child as to physically change a figure for a desired item. This includes as to reach, to catch and to deliver the figure at the hands of the professors with the purpose to ask for the desired item. For this she is necessary that the objects desired for the corresponding child and figures are in sight; 2.Fase II? Expanding the espontaneidade: The professor must be next to the child.