Jonikaitis Donatas, Klapetek Anna, Deubel Heiner
Department of Neurobiology and Howard Hughes Medical Institute, Stanford University School of Medicine, Stanford, California.
Allgemeine und Experimentelle Psychologie, Department Psychologie, Ludwig-Maximilians-Universität München, Munich, Germany; and.
J Neurophysiol. 2017 Jul 1;118(1):149-160. doi: 10.1152/jn.00665.2016. Epub 2017 Mar 29.
Behavioral measures of decision making are usually limited to observations of decision outcomes. In the present study, we made use of the fact that oculomotor and sensory selection are closely linked to track oculomotor decision making before oculomotor responses are made. We asked participants to make a saccadic eye movement to one of two memorized target locations and observed that visual sensitivity increased at both the chosen and the nonchosen saccade target locations, with a clear bias toward the chosen target. The time course of changes in visual sensitivity was related to saccadic latency, with the competition between the chosen and nonchosen targets resolved faster before short-latency saccades. On error trials, we observed an increased competition between the chosen and nonchosen targets. Moreover, oculomotor selection and visual sensitivity were influenced by top-down and bottom-up factors as well as by selection history and predicted the direction of saccades. Our findings demonstrate that saccade decisions have direct visual consequences and show that decision making can be traced in the human oculomotor system well before choices are made. Our results also indicate a strong association between decision making, saccade target selection, and visual sensitivity. We show that saccadic decisions can be tracked by measuring spatial attention. Spatial attention is allocated in parallel to the two competing saccade targets, and the time course of spatial attention differs for fast-slow and for correct-erroneous decisions. Saccade decisions take the form of a competition between potential saccade goals, which is associated with spatial attention allocation to those locations.
决策的行为测量通常仅限于对决策结果的观察。在本研究中，我们利用了眼动和感觉选择紧密相连这一事实，以便在做出眼动反应之前追踪眼动决策。我们要求参与者向两个记忆中的目标位置之一进行扫视眼动，并观察到在所选和未选的扫视目标位置视觉敏感度均有所提高，且明显偏向所选目标。视觉敏感度变化的时间进程与扫视潜伏期相关，在短潜伏期扫视之前，所选和未选目标之间的竞争解决得更快。在错误试验中，我们观察到所选和未选目标之间的竞争加剧。此外，眼动选择和视觉敏感度受自上而下和自下而上的因素以及选择历史的影响，并能预测扫视的方向。我们的研究结果表明，扫视决策具有直接的视觉后果，并表明在做出选择之前很久，决策就可以在人类眼动系统中得到追踪。我们的结果还表明决策、扫视目标选择和视觉敏感度之间存在密切关联。我们表明，可以通过测量空间注意力来追踪扫视决策。空间注意力并行分配到两个相互竞争的扫视目标上，并且快速 - 慢速决策和正确 - 错误决策的空间注意力时间进程有所不同。扫视决策采取潜在扫视目标之间竞争的形式，这与对这些位置的空间注意力分配相关。
