Wagner Ilja, Tünnermann Jan, Schubö Anna, Schütz Alexander C
Justus Liebig University, Giessen, Germany.
Experimental and Biological Psychology, University of Marburg, Marburg, Germany.
J Neurophysiol. 2025 May 1;133(5):1350-1367. doi: 10.1152/jn.00488.2024. Epub 2025 Mar 26.
Humans must weigh various factors when choosing between competing courses of action. In case of eye movements, for example, a recent study demonstrated that the human oculomotor system trades off the temporal costs of eye movements against their perceptual benefits when choosing between competing visual search targets. Here, we compared such trade-offs between different effectors. Participants were shown search displays with targets and distractors from two stimulus sets. In each trial, they chose which target to search for, and, after finding it, discriminated a target feature. Targets differed in their search costs (how many target-similar distractors were shown) and discrimination difficulty. Participants were rewarded or penalized based on whether the target's feature was discriminated correctly. In addition, participants were given a limited time to complete trials. Critically, they inspected search items either by eye movements only or by manual actions (tapping a stylus on a tablet). Results show that participants traded off search costs and discrimination difficulty of competing targets for both effectors, allowing them to perform close to the predictions of an ideal observer model. However, behavioral analysis and computational modeling revealed that oculomotor search performance was more strongly constrained by decision-noise (what target to choose) and sampling-noise (what information to sample during search) than manual search. We conclude that the trade-off between search costs and discrimination accuracy constitutes a general mechanism to optimize decision-making, regardless of the effector used. However, slow-paced manual actions are more robust against the detrimental influence of noise, compared with fast-paced eye movements. Humans trade off costs and perceptual benefits of eye movements for decision-making. Is this trade-off effector-specific or does it constitute a general decision-making principle? Here, we investigated this question by contrasting eye movements and manual actions (tapping a stylus on a tablet) in a search task. We found evidence for a cost-benefit trade-off in both effectors, however, eye movements were more strongly compromised by noise at different levels of decision-making.
人类在选择相互竞争的行动方案时必须权衡各种因素。例如，在眼球运动方面，最近的一项研究表明，人类眼动系统在选择相互竞争的视觉搜索目标时，会在眼球运动的时间成本与其感知收益之间进行权衡。在此，我们比较了不同效应器之间的这种权衡。向参与者展示包含来自两个刺激集的目标和干扰项的搜索显示。在每次试验中，他们选择搜索哪个目标，找到目标后，辨别目标特征。目标在搜索成本（展示了多少与目标相似的干扰项）和辨别难度上有所不同。根据目标特征是否被正确辨别，参与者会得到奖励或惩罚。此外，给参与者限定时间来完成试验。关键的是，他们仅通过眼球运动或手动操作（在平板电脑上用触控笔点击）来检查搜索项目。结果表明，参与者在两种效应器中都权衡了竞争目标的搜索成本和辨别难度，使他们的表现接近理想观察者模型的预测。然而，行为分析和计算建模表明，与手动搜索相比，眼动搜索性能受决策噪声（选择哪个目标）和采样噪声（在搜索过程中采样哪些信息）的约束更强。我们得出结论，搜索成本与辨别准确性之间的权衡构成了一种优化决策的通用机制，无论使用何种效应器。然而，与快速的眼球运动相比，节奏较慢的手动操作对噪声的有害影响更具鲁棒性。人类在决策时会权衡眼球运动的成本和感知收益。这种权衡是特定于效应器的，还是构成了一种通用的决策原则呢？在此，我们通过在搜索任务中对比眼球运动和手动操作（在平板电脑上用触控笔点击）来研究这个问题。我们发现两种效应器都存在成本效益权衡的证据，然而，在不同决策水平上，眼球运动受噪声的影响更大。
