On the role of trial types in tests for stimulus equivalence


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Series/Report no

European Journal of Behavior Analysis;10(2)


Norwegian Association for Behavior Analysis

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Some studies which have shown that differences in outcome on tests for stimulus equivalence dependent on different training structures, have run the tests as separate blocks without baseline trials interspersed in between test trials. Saunders and co-workers have argued that the differences in test outcome could be related to differences in the retention of trained discriminations during testing (R. R. Saunders, Drake, & Spradlin, 1999; R. R. Saunders & Green, 1999). In the current experiment, 20 adult participants were taught conditional relations by employing a linear series training structure. Following this training, non-reinforced trials of the directly trained relations were randomly interspersed in a mixed test for symmetry, transitivity, and global equivalence. After being exposed to the training procedure once, 17 of the participants did not perform in accord with stimulus equivalence, but 9 of these participants still responded in accord with the directly trained relations. After being exposed to the training procedure again, 10 participants still did not respond in accord with stimulus equivalence, while 7 out of these did respond consistent with the directly trained relations. This indicates that a “destroyed” baseline could not be responsible for these participants’ failure to respond in accord with stimulus equivalence. In addition the reaction time between the appearance of comparison stimuli and subsequent responding during the test were recorded. Data show that the average reaction time varies as a function of which type of relation that is presented. There were also distinct differences in reaction time patterns for those participants who responded in accord with stimulus equivalence compared to those not responding in such a manner


Permanent URL (for citation purposes)

  • http://hdl.handle.net/10642/932