Makris Stergios, Hadar Aviad A, Yarrow Kielan
Department of Human Sciences, University of Udine.
Behav Neurosci. 2013 Oct;127(5):797-802. doi: 10.1037/a0033946.
Inspired in part by Gibson's (1979) ecological approach to perception, current neurocognitive theories of action suggest that the simple viewing of an object can automatically elicit motor programs for specific acts. However, the degree to which such affordances should be considered truly automatic is unknown. Here we explored the generation of motor plans afforded by pairs of cue objects that were viewed peripherally under different attentional states. Participants focused centrally while attending to just one of two peripheral cue objects that together had a strong significance for pinching, grasping, or both. They were instructed to ignore the objects and instead give power or precision grip responses to subsequent changes in background color. The data showed a significant interaction between type of response and type of object, indicating that object affordances are perceived even in nonfoveal vision. Critically, the generation of affordances was modulated by the locus of attention: Motor preparation was biased toward the attended object when two different categories of object appeared in the same trial, but the generation of affordances was also influenced by unattended stimuli. This finding demonstrates that object-action priming is not completely automatic, instead being constrained by processes of perceptual selection.
部分受吉布森（1979年）的生态知觉方法启发，当前的动作神经认知理论表明，简单地观看一个物体就能自动引发特定动作的运动程序。然而，这种可供性在何种程度上应被视为真正自动的尚不清楚。在这里，我们探讨了在不同注意状态下，外周视觉中一对提示物体所提供的运动计划的产生。参与者在集中注意力于中央的同时，只关注两个外周提示物体中的一个，这两个物体合在一起对捏、抓握或两者都有很强的指示意义。他们被指示忽略这些物体，而是对随后背景颜色的变化做出力量或精确抓握反应。数据显示反应类型和物体类型之间存在显著交互作用，表明即使在非中央凹视觉中也能感知到物体的可供性。至关重要的是，可供性的产生受到注意力焦点的调节：当同一试验中出现两类不同物体时，运动准备偏向于被关注的物体，但可供性的产生也受到未被关注刺激的影响。这一发现表明，物体-动作启动并非完全自动，而是受到知觉选择过程的制约。
