Donald M. Baer

Reinforcement control of generalized imitation in young children

Abstract Three imitative responses (head nodding, mouthing, and strange verbalizations) were established in young children by social reinforcement from a puppet. A fourth imitative response (bar-pressing), which was never reinforced, was found to increase in strength when reinforcement followed the other three imitative responses. This increase in imitative bar-pressing was taken to indicate that a generalized similarity of responding between puppet and child could be a reinforcing stimulus dimension in the childs behavior. Two additional procedures were applied to demonstrate further the dependence of imitative bar-pressing upon the reinforcement following the other imitative responses. These additional procedures were extinction of the other imitative responding, and time-out from the other imitative responding. In extinction, reinforcement was no longer presented following imitative head nodding, mouthing, and strange verbalizations, but was instead presented in a noncontingent manner during the normal conversation between puppet and child. As a consequence, imitative bar-pressing decreased in strength. When reinforcement was reinstated for the other imitative responses, imitative bar-pressing again rose in strength. During time-out periods, the puppet ceased to provide the child with head nodding, mouthing, and strange verbalization performances for the child to imitate. Again, social reinforcement was continued at the same rate but was delivered during the normal puppet-child conversation. The effect of the time-out was to decrease the strength of imitative bar-pressing. Reinstatement of the cues and reinforcement for imitative head nodding, mouthing, and strange verbalizations produced increased imitative bar-pressing.

Some Methodological Contributions From a Functional Analysis of Child Development1

Publisher Summary This chapter discusses two methodological problems of child behavior and development from a “functional point of view.” This phrase implies an approach in which only objectively defined concepts are used and the behaviors of the children are related directly to observable elements of their present circumstances and past interactional history. On the surface, this description may seem to be merely a reiteration of nearly universal current research practices with children. On closer scrutiny, this is found not to be the case. Therefore, prior to discussions of research, the chapter makes clear the meaning of psychological development, points out some of its implications, and takes a specific view of the nature of development.

Imprinting to a Different Species without Overt following

Infantile social attachment to the parent or parent-surrogate as a process of learning within a specific period of the infant animals life was first reported in the early 1870s by the Scottish behaviorist, Douglas Spalding (1873). Laboratory investigations of this phenomenon, now generically called imprinting, invariably have used artificial models as surrogates and the following response of the young as an index of both readiness to imprint and retention of imprinting (cf. Gray, 1958). Writers have frequently considered the following response itself as learned (Verplanck, 1958), as reinforcing (Thorpe, 1957 ) , or even as a source of an afferent feedback positively related to degree of imprinting (Hess, 1959). This unilateral emphasis on following, which Spalding thought of as an unlearned response, has tended to divert attention from a more general operational definition of imprinting: an acquired ability to discriminate the object to which the young animal has been sufficiently exposed at a critical age. The principal aim of this experiment was to separate the following response from this acquired ability to discriminate. The method was designed to give the infant animal visual experience with a parent-surrogate, but to prevent overt following or any form of contact response. W e neither prevented nor measured the orienting response which necessarily is the first part of the following response, since orienting is presumably integral to any kind of learning in such a situation. The specific question was whether a chick will form an attachment, expressible as a discrimination, without overt following or any other independently specifiable reinforcement or drive reduction.