The Effect of Arousal and of Learning upon Sucking Behavior in the Newborn

There is increasing evidence that the first experiences of animal and man have a significant influence on their later psychological development. Food is one of the earliest reinforcements for the neonate, and therefore the feeding experience may be the primal activity which initiates and maintains the infant’s subsequent repertoire of behavior. Behavioral-control techniques are useful methods for evaluating the effect of rein-forcers such as food upon the acquisition and maintenance of behavior. The mammalian newborn obtains its food primarily by sucking. Therefore, by using the operant level of sucking as a base line, it is possible to define reinforcement in terms of response probability, and to analyze experimentally the relationship between environmental contingencies and sucking behavior. A behavioral-control technique utilizing sucking as the operant was developed in our laboratory to deter mine the mechanisms by which the early feeding experience modifies behavior.