Rohde Marieke, Scheller Meike, Ernst Marc O
Department of Cognitive Neuroscience, University of Bielefeld, Universitätsstr. 25, W3-240, 33615 Bielefeld, Germany; Cognitive Interaction Technology (CITEC) Center of Excellence, University of Bielefeld, Inspiration 1, 33619 Bielefeld, Germany.
Department of Cognitive Neuroscience, University of Bielefeld, Universitätsstr. 25, W3-240, 33615 Bielefeld, Germany.
Neuropsychologia. 2014 Dec;65:191-6. doi: 10.1016/j.neuropsychologia.2014.10.011. Epub 2014 Oct 19.
The sense of agency, i.e., the feeling that one׳s action is the cause of an external sensory event, involves causal inference based on the predicted sensory outcome of a motor act. Here, we investigated whether this inference process faithfully implements the physical principle that a cause (motor act) temporally precedes its effect (external sensory feedback). To this end, we presented participants with visual flashes that were temporally offset from voluntary button presses, including scenarios where the flash occurred shortly before the press. Participants then judged their experience of agency. As expected, cause-effect order is an important cue for this task: participants were far more likely to report agency for temporally lagging flashes than for leading flashes, even if very long sensory delays also disrupted the sense of agency (Experiment 1). This suggests that the temporal order between action and sensation is the dominant temporal cue for agency. However, when participants judged whether they had caused a first flash that occurred before the button press or a second flash that occurred afterwards, the temporal threshold for rejecting leading first flashes was relaxed proportionally to the delay of the second flash (Experiment 2). There was competition between different sensorimotor timing cues (temporal order favored the second flash and temporal proximity favored the first flash), and participants׳ tolerance for cause-effect inversions was modulated by the strength of the later, conflicting cue. We conclude that the perceived order of action and sensation is not used in a winner-take-all fashion in inference of agency. Instead, a probabilistic negotiation of the different timing cues favoring different flash events takes place postdictively, after presentation of the second flash.
能动感,即认为自己的行动是外部感官事件的原因的感觉,涉及基于运动行为预测的感官结果的因果推理。在此,我们研究了这种推理过程是否忠实地遵循了物理原则,即原因(运动行为)在时间上先于其结果(外部感官反馈)。为此,我们向参与者呈现视觉闪光,这些闪光在时间上与自愿按键不同步,包括闪光在按键前不久发生的情况。然后,参与者判断他们的能动体验。正如预期的那样,因果顺序是这项任务的一个重要线索:参与者报告对时间上滞后的闪光的能动感的可能性远高于对超前闪光的能动感,即使很长的感官延迟也会破坏能动感(实验1)。这表明行动和感觉之间的时间顺序是能动感的主要时间线索。然而,当参与者判断他们是否导致了在按键之前发生的第一次闪光或之后发生的第二次闪光时,拒绝超前第一次闪光的时间阈值与第二次闪光的延迟成比例地放宽(实验2)。不同的感觉运动时间线索之间存在竞争(时间顺序有利于第二次闪光,时间接近有利于第一次闪光),参与者对因果倒置的容忍度受到后来冲突线索强度的调节。我们得出结论,在能动推理中,行动和感觉的感知顺序并非以赢家通吃的方式使用。相反,在呈现第二次闪光后,会对有利于不同闪光事件的不同时间线索进行概率性协商。