Disrupting delayed matching-to-sample performance with varied distractor tasks

ABSTRACTExplanations of delayed stimulus control (e.g., delayed matching-to-sample, sequencing stimuli under the control of spoken instructions) and other instances of joint control often rely on “mediating” behavior, typically echoic responses occurring throughout the delay, to explain how stimuli no longer present can control behavior. While covert mediation itself cannot be observed, several researchers have looked at different procedures that disrupt potential performance by “blocking” presumed covert mediation by engaging in unrelated overt verbal behavior to tell us more about the nature of this putative mediation. In this study, preschool-aged children were taught to tact pictures of familiar objects and select them from an array of eight. During delayed matching-to-sample (DMTS) trials, participants were required to either talk to the experimenter, look at distractor pictures, or match figures using a tangram toy. The type of “blocking” activity during the delay was manipulated in a test-retest multiple treatment design, and the resulting DMTS performance was compared. With some individual differences, the distractor task assumedly most incompatible with covert verbal rehearsal, a conversational interview, was the least disruptive to performance. These data suggest refraining from assuming performance reductions during “blocking” are caused by incompatibility with covert mediation.KEYWORDS: Covert behaviorprivate eventsjoint controldelayed matching-to-sampleverbal behaviormediation Disclosure statementNo potential conflict of interest was reported by the author(s).Compliance with ethical standardsThe authors have no known conflicts of interest. This study’s procedures were reviewed and approved by the Institutional Review Board for Human Subjects Research at our institution and have been performed in accordance with the ethical standards as laid down in the 1964 Declaration of Helsinki and its later amendments. All participants assented to the study and their parent/guardian gave their informed consent.