Paper in Learning & Behavior
  • Harris, J. A., Gharaei, S., & Moore, C. A. (2009). Representations of single and compound stimuli in negative and positive patterning. Learning & Behavior, 37, 230-245.

    ABSTRACT
    In four experiments, rats were trained on different patterning discriminations before being tested with com- pounds composed of novel combinations of the trained stimuli. In Experiment 1, rats were trained on a negative- patterning schedule (A+ B+ AB -) intermixed with reinforced presentations of a second compound (CD+). On a subsequent test, the rats responded more to two novel compounds, AC and BD, than to A and B, but less than to CD. In Experiment 2, rats were trained on two concurrent negative-patterning discriminations (A+ B+ AB-, C+ D+ CD-). On test, they responded more to AC and BD than to AB and CD, but less than to the single stimuli. In Experiment 3, rats were trained on two concurrent positive-patterning discriminations (A- B- AB+, C- D- CD+). On test, their response rates to AC and BD were not different from the response rates to the trained compounds (AB and CD). Finally, in Experiment 4, rats were trained on a positive- and negative- patterning discrimination concurrently. Once again, on test, response rates to AC and BD were not different from responding on reinforced trials of the trained discriminations (A+, B+, and CD+). We discuss the implications of these findings for elemental and configural models of stimulus representation.