Ongoing goal-directed movements can be rapidly adjusted following new environmental information, e.g., when chasing pray or foraging. This makes movement trajectories in go-before-you-know decision-making a suitable behavioral readout of the ongoing decision process. Yet, existing methods of movement analysis are often based on statistically comparing two groups of trial-averaged trajectories and are not easily applied to three-dimensional data, preventing them from being applicable to natural free behavior. We developed and tested the cone method to estimate the point of overt commitment (POC) along a single two- or three-dimensional trajectory, i.e., the position where the movement is adjusted towards a newly selected spatial target. In Experiment 1, we established a “ground truth” data set in which the cone method successfully identified the experimentally constrained POCs across a wide range of all but the shallowest adjustment angles. In Experiment 2, we demonstrate the power of the method in a typical decision-making task with expected decision time differences known from previous findings. The POCs identified by cone method matched these expected effects. In both experiments, we compared the cone method’s single trial performance with a trial-averaging method and obtained comparable results. We discuss the advantages of the single-trajectory cone method over trial-averaging methods and possible applications beyond the examples presented in this study. The cone method provides a distinct addition to existing tools used to study decisions during ongoing movement behavior, which we consider particularly promising towards studies of non-repetitive free behavior.

持续的目标导向运动可以根据新的环境信息快速调整，例如，在追逐祈祷或觅食时。这使得先行后知决策中的运动轨迹成为正在进行的决策过程的合适行为读数。然而，现有的运动分析方法通常基于对两组试验平均轨迹的统计比较，并且不容易应用于三维数据，从而阻止它们适用于自然自由行为。我们开发并测试了锥形方法估计沿单个二维或三维轨迹的明显承诺点（POC），即向新选择的空间目标调整运动的位置。在实验 1 中，我们建立了一个“ground truth”数据集，其中锥形方法成功地识别了除最浅调整角之外的所有范围内的实验约束 POC。在实验 2 中，我们展示了该方法在典型决策任务中的强大功能，其中预期的决策时间差异从先前的发现中已知。通过锥法确定的 POC 与这些预期效果相匹配。在这两个实验中，我们将锥法的单次试验性能与试验平均法进行了比较，并获得了可比较的结果。我们讨论了单轨迹锥方法相对于试验平均方法的优势以及本研究中提供的示例之外的可能应用。锥形方法为用于研究正在进行的运动行为期间的决策的现有工具提供了一个独特的补充，我们认为这对非重复自由行为的研究特别有希望。