Gibo Tricia L, Mugge Winfred, Abbink David A
Department of BioMechanical Engineering, Faculty of 3 mE, Delft University of Technology, Mekelweg 2, 2628 CD, Delft, The Netherlands.
Exp Brain Res. 2017 Aug;235(8):2533-2546. doi: 10.1007/s00221-017-4986-4. Epub 2017 May 22.
To effectively interpret and interact with the world, humans weight redundant estimates from different sensory cues to form one coherent, integrated estimate. Recent advancements in physical assistance systems, where guiding forces are computed by an intelligent agent, enable the presentation of augmented cues. It is unknown, however, if cue weighting can be extended to augmented cues. Previous research has shown that cue weighting is determined by the reliability (inversely related to uncertainty) of cues within a trial, yet augmented cues may also be affected by errors that vary over trials. In this study, we investigate whether people can learn to appropriately weight a haptic cue from an intelligent assistance system based on its error history. Subjects held a haptic device and reached to a hidden target using a visual (Gaussian distributed dots) and haptic (force channel) cue. The error of the augmented haptic cue varied from trial to trial based on a Gaussian distribution. Subjects learned to estimate the target location by weighting the visual and augmented haptic cues based on their perceptual uncertainty and experienced errors. With both cues available, subjects were able to find the target with an improved or equal performance compared to what was possible with one cue alone. Our results show that the brain can learn to reweight augmented cues from intelligent agents, akin to previous observations of the reweighting of naturally occurring cues. In addition, these results suggest that the weighting of a cue is not only affected by its within-trial reliability but also the history of errors.
为了有效地理解世界并与之互动，人类会权衡来自不同感官线索的冗余估计，以形成一个连贯、综合的估计。在物理辅助系统中，引导力由智能代理计算，最近的进展使得增强线索得以呈现。然而，线索加权是否可以扩展到增强线索尚不清楚。先前的研究表明，线索加权由试验中线索的可靠性（与不确定性成反比）决定，但增强线索也可能受到试验间变化的误差影响。在本研究中，我们调查人们是否可以根据智能辅助系统的错误历史学会适当地权衡触觉线索。受试者手持触觉设备，利用视觉（高斯分布的点）和触觉（力通道）线索伸向一个隐藏目标。增强触觉线索的误差根据高斯分布在试验间变化。受试者学会根据视觉和增强触觉线索的感知不确定性和经历的误差来估计目标位置。与仅使用一个线索时相比，当两个线索都可用时，受试者能够以更好或相同的表现找到目标。我们的结果表明，大脑可以学会重新权衡来自智能代理的增强线索，这类似于之前对自然出现线索重新加权的观察。此外，这些结果表明，线索的加权不仅受其试验内可靠性的影响，还受错误历史的影响。
