A Connectionist Model of Stimulus Class Formation with a Yes/No Procedure and Compound Stimuli

We analyzed stimulus class formation in a human study and in a connectionist model (CM) with a yes/no procedure, using compound stimuli. In the human study, the participants were six female undergraduate students; the CM was a feed-forward back-propagation network. Two 3-member stimulus classes were trained with a similar procedure in both the human participants and the model. During training, the compound stimuli A1B1, A2B2, B1C1, B2C2 were associated with the yes response, and A1B2, A2B1, B1C2, B2C1 were associated with the no response. During testing, we probe the emergence of the yes and no responses in the presence of new compound stimuli (A1C1, A2C2, A1C2, A2C1). Four participants and five out of six runs of the CM exhibited stimulus class formation. These results show the usefulness of the yes/no procedure for simulating stimulus class formation in a CM in contrast with the models inspired in matching-to-sample procedures.