Abstract
In real-world visual search, there are often multiple different strategies for controlling attention (e.g., searching for an item's color, shape, or size). Recently we found that when observers are free to choose between different attentional control settings, they often make sub-optimal choices. We attributed this finding to a performance-effort trade-off. Specifically, observers sometimes forgo an optimal but cognitively-demanding setting in favor of one that is less effortful and less effective. However, an alternative explanation is that they simply lack the necessary knowledge to determine the best strategy. To compare accounts, we directly manipulated the motivation to maximize performance by rewarding fast visual search. Participants (N = 48) performed the adaptive choice visual search task, in which they were free to choose between two different search targets. The proportion of target-similar items in the display varied over time, such that the optimal target choice changed periodically. A baseline phase was followed by a reward phase, in which each trial earned a monetary reward based on response speed (performance contingent group), or assigned at random (random reward group). Results showed that the performance contingent group made significantly more optimal choices and were significantly faster in the reward phase compared to baseline. The random reward group showed no such improvement. The findings argue against the view that sub-optimal performance was due to limited knowledge, and show that the choice of attentional control settings is sensitive to the trade-off between effort and reward. Further, they emphasize the importance of considering motivation in developing a greater understanding of goal-directed attentional control.
Meeting abstract presented at VSS 2017