Dissociations and interactions between attention guidance from negative templates maintained in visual working memory...

Visual attention can be guided away from objects known to be irrelevant to the current task. These negative templates (specifying distractor features) can be maintained in visual working memory (VWM) and in long-term memory (LTM). LTM-based negative templates allow for direct suppression of to-be-avoided feature values, observable in the earliest selective operations during search (i.e., implemented proactively). However, there is mixed evidence regarding whether VWM-based negative templates are likewise implemented directly and proactively. Here, we contrasted LTM- and VWM-based negative guidance within the same visual search experiment. There were two broad lines of findings. First, the two sources of guidance dissociated on several measures of oculomotor orienting during visual search, including: a) the polarity of initial guidance, b) the latency of initial orienting, and c) the pattern of guidance across an extended search trial. We conclude that the two forms of guidance are implemented by fundamentally different mechanisms. Second, we created conditions in which the two forms of guidance were potentially operational within the same trial, testing their interaction. Both were expressed within a trial when they specified different sets of objects. However, VWM-based biases dominated when the two biases were placed in competition, indicating that online attentional sets tend to overshadow learned biases in the computation of priority.