Institute of Biomedical Engineering, University of New Brunswick, Fredericton, Canada.
School of Health Sciences, Faculty of Medicine and Health, Örebro University, 701 82, Örebro, Sweden.
J Neuroeng Rehabil. 2024 Aug 31;21(1):148. doi: 10.1186/s12984-024-01445-3.
Eye tracking technology not only reveals the acquisition of visual information at fixation but also has the potential to unveil underlying cognitive processes involved in learning to use a multifunction prosthetic hand. It also reveals gaze behaviours observed during standardized tasks and self-chosen tasks. The aim of the study was to explore the use of eye tracking to track learning progress of multifunction hands at two different time points in prosthetic rehabilitation.
Three amputees received control training of a multifunction hand with new control strategy. Detailed description of control training was collected first. They wore Tobii Pro2 eye-tracking glasses and performed a set of standardized tasks (required to switch to different grips for each task) after one day of training and at one-year-follow-up (missing data for Subject 3 at the follow up due to socket problem). They also performed a self-chosen task (free to use any grip for any object) and were instructed to perform the task in a way how they would normally do at home. The gaze-overlaid videos were analysed using the Tobii Pro Lab and the following metrics were extracted: fixation duration, saccade amplitude, eye-hand latency, fixation count and time to first fixation.
During control training, the subjects learned 3 to 4 grips. Some grips were easier, and others were more difficult because they forgot or were confused with the switching strategies. At the one-year-follow-up, a decrease in performance time, fixation duration, eye-hand latency, and fixation count was observed in Subject 1 and 2, indicating an improvement in the ability to control the multifunction hand and a reduction of cognitive load. An increase in saccade amplitude was observed in both subjects, suggesting a decrease in difficulty to control the prosthetic hand. During the standardized tasks, the first fixation of all three subjects were on the multifunction hand in all objects. During the self-chosen tasks, the first fixations were mostly on the objects first.
The qualitative data from control training and the quantitative eye tracking data from clinical standardized tasks provided a rich exploration of cognitive processing in learning to control a multifunction hand. Many prosthesis users prefer multifunction hands and with this study we have demonstrated that a targeted prosthetic training protocol with reliable assessment methods will help to lay the foundation for measuring functional benefits of multifunction hands.
眼动追踪技术不仅揭示了在注视时获取视觉信息的情况，还有可能揭示学习使用多功能假肢手所涉及的潜在认知过程。它还揭示了在标准化任务和自选任务中观察到的注视行为。本研究的目的是探索使用眼动追踪技术在假肢康复的两个不同时间点跟踪多功能手的学习进展。
三名截肢者接受了新控制策略的多功能手控制训练。首先详细描述了控制训练。他们戴上 Tobii Pro2 眼动追踪眼镜，在训练一天后和一年随访时（由于插座问题，受试者 3 的随访数据丢失）进行了一组标准化任务（要求为每个任务切换到不同的抓握方式）。他们还进行了自选任务（自由使用任何抓握方式抓取任何物体），并被指示按照他们在家中通常的方式完成任务。使用 Tobii Pro Lab 分析了叠加注视视频，并提取了以下指标：注视持续时间、眼跳幅度、眼手潜伏期、注视次数和首次注视时间。
在控制训练过程中，受试者学习了 3 到 4 种抓握方式。有些抓握方式更容易，而有些则更困难，因为他们忘记或混淆了切换策略。在一年随访时，受试者 1 和 2 的动作时间、注视持续时间、眼手潜伏期和注视次数减少，表明他们控制多功能手的能力提高，认知负荷降低。两个受试者的眼跳幅度都有所增加，表明控制假肢手的难度降低。在标准化任务中，所有三个受试者在所有物体上的首次注视点都是多功能手。在自选任务中，首次注视点大多在物体上。
控制训练的定性数据和临床标准化任务的定量眼动追踪数据为学习控制多功能手的认知处理过程提供了丰富的探索。许多假肢使用者更喜欢多功能手，通过这项研究，我们证明了具有可靠评估方法的靶向假肢训练方案将有助于为测量多功能手的功能益处奠定基础。
