Effort expectation and strategic cue use in visual search.

Positive cues provide information about target features, facilitating processing of the upcoming input. The role of "negative cues," which signal distractor features, is less clear. Their use seems to incur a certain mental effort, and consequently, their effectiveness could depend on whether the benefit of reducing search effort outweighs the effort required to use them. Crucially, when search effort is predictable, participants can rely on expected effort in deciding whether to use a negative cue. This subjective effort/benefit evaluation may explain the inconsistent effects sometimes observed with negative cues. However, the influence of expected effort has not yet been examined in this context. Varying effort expectation may provide a way to test this prediction. To this end, we manipulated effort expectation by embedding a small number of easy trials within blocks of mainly difficult trials and vice versa. We assumed that expected effort can boost cue utilization, especially when a difficult search was expected. The impact of positive and negative cues was compared to neutral cues under identical expectations. We found that benefits of positive cues increased when search was more effortful. Negative cueing effects, however, showed no reliable benefits, even when higher effort was expected. Interestingly, search performance was better when the expected effort matched actual task difficulty, though this pattern was more robust in difficult compared to easy trials. This asymmetry reveals an interaction between effort expectation and task difficulty. We discuss the neural underpinnings of how these factors might influence visual search.