Fifty-three undergraduate students were exposed to the computer task of making sentences. The experiment started with baseline, in which no reinforcement was applied. During the experimental condition, subjects in different groups had the use of a specific pronoun previously selected by the experimenter under the contingencies of positive and negative reinforcement. The results described a systematic pattern among subjects towards the frequency distribution of pronouns used during the baseline. During the reinforcement condition, there was the increase in the frequency of the pronouns under reinforcement. In the present study, the negative reinforcement contingency (vs. the positive one) resulted in greater increase in the use of the selected pronoun. These data suggest different effects of the positive and negative reinforcement contingencies on the human behavior, evaluated not only in ethical conditions, but also in the learning context that aims to establish scientific attitudes.
undergratuate; verbal behavior; contingencies of reinforcement; teaching activity