On the influence of spatial and value attentional cues across individuals
The visual world provides a myriad of cues every instance that can be used to direct information processing. How does the brain integrate predictive information from disparate sources to modify visual priorities, and are combination strategies consistent across individuals? Previous evidence shows that sensory cues that are predictive of the value of a visually guided task (incentive value) and cues that signal where task-relevant stimuli may occur (spatial certainty) act independently to bias attention. Anticipatory accounts propose that both cues are comparably encoded into an attentional priority map, whereas the counterfactual account argues that incentive value cues instead induce a reactive encoding of losses based on the direction of attention. Here we adjudicate between these alternatives and further determine whether there are individual differences in how attentional cues are encoded. 149 participants viewed two coloured placeholders that specified the potential value of correctly identifying an imminent target if it appeared in that specific placeholder. Prior to the target’s presentation, an endogenous spatial cue indicated the target’s more likely location. The anticipatory and counterfactual accounts were used to motivate parametric regressors that were compared in their explanatory power of the observed data, at the group level and on data stratified by a clustering algorithm applied to identify individual differences. The algorithm revealed 2 subtypes in the population; whereas all individuals use spatial certainty cues a subset does not use incentive value cues. However, when used, the influence of incentive value cues reflects a counterfactual loss function. The data show that spatial certainty and incentive value act independently to influence visual priorities because they act at distinct points in information processing, and that theories of motivated attention must account for the non-uniform influence of incentive value on visual priorities.