What factors determine the implementation of attentional set? It is often assumed that set is determined only by experimenter instructions and characteristics of the immediate stimulus environment, yet it is likely that other factors play a role. The present experiments were designed
to evaluate the latter possibility; specifically, the role of past experience was probed. In a 320-trial training phase, observers could use one of two possible attentional sets (but not both) to find colour-defined targets in a rapid serial visual presentation (RSVP) stream of letters. In
the subsequent 320-trial test phase, where either set could be used, observers persisted in using their pre-established sets through the remainder of the experiment, affirming a clear role of past experience in the implementation of attentional set. A second experiment revealed that sufficient
experience with a given set was necessary to facilitate persistence with it. These results are consistent with models of executive control (e.g., Norman & Shallice, 1986), in which “top-down” behaviours are influenced by learned associations between tasks and the environment.