Lab. for Neurocognitive Technology, NRC "Kurchatov Institute", Moscow, Russia.
MEG Center, Moscow State University of Psychology and Education, Moscow, Russia.
Exp Brain Res. 2021 Jun;239(6):1951-1961. doi: 10.1007/s00221-021-06105-9. Epub 2021 Apr 20.
In this paper, we propose an experimental technique for studying the sense of agency (SoA) in joint human-machine actions. This technique is based on the use of an electromechanical finger-lifting device that enables a joint motor action initiated by a participant and completed by the machine. The joint action, later referred to as an "active-passive" action, was implemented as a reaction time task and contrasted with other levels of participant's involvement, including active movement, passive movement, and observation of a dummy's movement. In each trial, a feedback sound signal informed the participant whether they had performed the task successfully, i.e. faster than a threshold, which was individually adjusted in the beginning of the experiment. In the active condition, the result depended on the participant, while in other conditions it was preprogrammed for the servo. In context of this task, we studied direct time estimates made by participants and auditory event-related potentials (ERP) in 20 healthy volunteers. The amplitude of the auditory N1 component in the responses to the feedback sound showed no significant effect of activity and success factors, while its latency was shorter in successful trials. Interaction of activity and success factors was significant for subjective time estimates. Surprisingly, the intentional binding effect (subjective compression of time intervals, which is known as a correlate of SoA) only emerged in trials of active condition with negative results. This observation was in contrast with the fact that the active and active-passive movements were both voluntarily initiated by the participant. We believe that studying SoA with the proposed technique may not only add to the understanding of agency but also provide practically relevant results for the development of human-machine systems such as exoskeletons.
在本文中，我们提出了一种用于研究联合人机动作中的主体意识（SoA）的实验技术。该技术基于使用机电手指提升装置，该装置使参与者发起的联合电机动作由机器完成。该联合动作后来被称为“主动-被动”动作，作为反应时间任务实施，并与参与者参与的其他水平进行对比，包括主动运动、被动运动和观察假人的运动。在每次试验中，反馈声音信号告知参与者他们是否成功完成了任务，即比阈值快，该阈值在实验开始时根据个人进行调整。在主动条件下，结果取决于参与者，而在其他条件下，结果则由伺服器预先编程。在该任务的背景下，我们研究了 20 名健康志愿者的直接时间估计和听觉事件相关电位（ERP）。对反馈声音的响应中听觉 N1 成分的振幅没有显示出活动和成功因素的显著影响，而其潜伏期在成功试验中较短。活动和成功因素的相互作用对主观时间估计有显著影响。令人惊讶的是，只有在具有负结果的主动条件的试验中才出现了意图绑定效应（即主体对时间间隔的压缩，这是 SoA 的一个相关物）。这一观察结果与主动和主动-被动运动都是由参与者自愿发起的事实相矛盾。我们相信，使用所提出的技术研究 SoA 不仅可以增加对代理的理解，而且还可以为外骨骼等人机系统的开发提供实际相关的结果。
