It has been suggested that attention is guided by two factors that operate during associative learning: a predictiveness principle, by which attention is allocated to the best predictors of outcomes, and an uncertainty principle, by which attention is allocated to learn about the less-known features of the environment. Recent studies have shown that predictivenessdriven attention can operate rapidly and in an automatic way to exploit known relationships. The corresponding characteristics of uncertainty-driven attention, on the other hand, remain unexplored. In two experiments we examined whether both predictiveness and uncertainty modulate attentional processing in an adaptation of the dot probe task. This task provides a measure of automatic orientation to cues during associative learning. The stimulus-onset-asynchrony of the probe display was manipulated in order to explore temporal characteristics of predictiveness-and uncertainty-driven attentional effects. Results showed that the predictive status of cues determined selective attention, with faster attentional capture to predictive than to nonpredictive cues. In contrast, the level of uncertainty slowed down responses to the probe regardless of the predictive status of the cues. Both predictiveness-and uncertainty-driven attentional effects were very rapid (at 250 ms from cue onset) and automatically activated.
Keywords: attention, associative learning, dot probe, predictiveness, uncertainty.Downloaded by [University of London] at 09:14 13 May 2016 3 Visual attention determines which stimuli are preferentially processed. It allows for the focusing of limited cognitive resources on important aspects of the environment, to the detriment of processing less important information. Thus, in order to understand our cognitive system, it is crucial to investigate which factors modulate this selection process.These factors are usually divided into two mutually exclusive functional categories according to whether attentional modulation is caused by physical characteristics of the stimuli (i.e., stimulus-driven modulation) or is caused by cognitive factors such as goal-directed intentions or motivations (i.e., goal-directed modulation) (e.g., Corbetta & Shulman, 2002;Yantis, 2000). For example, when driving we might use goal-directed, top-down attention to prioritize processing of events on the road ahead, and to ignore conversation from the backseat. But a physically salient event (e.g., a sudden bang from behind the car) will capture our attention in an bottom-up, stimulus-driven fashion regardless of our goals (e.g., Theeuwes, 1992;Folk, Remington, & Johnston, 1992).However, it has recently been argued that there is a third category of influences on attentional selection that is neither fully goal-directed nor stimulus-driven, and which comes into play when people have had previous experience with stimuli. Specifically, it has been suggested that our attention is influenced by what we have learned about how stimuli relate to other events in the environment (...