Psychometric characterization of incidental feedback sources during grasping with a hand prosthesis.
Meike Annika Wilke, Christian Niethammer, Britta Meyer and 2 others
PMID 31823792WHAT IT FOUND
Able-bodied users could distinguish 1% changes in prosthesis closing speed using just sight and sound.
This incidental feedback was more accurate than a simple vibration interface, suggesting that adding vibration may offer little benefit unless it provides new information.
Key findings
01Participants could discriminate very small changes in prosthesis closing velocity using incidental visual and auditory feedback, with a just noticeable difference of 1% for sound and combined vision/sound.
02In an estimation task, the median absolute error was lower for sound (5.2%) and combined vision/sound (5.1%) than for visual-only (6.7%) or vibrotactile feedback (8.4%).
03Participants relied primarily on the duration of the feedback stimulus rather than intensity or frequency to estimate closing speed.
STILL TO COME
How it was doneWhat they found
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study used able-bodied, naïve participants who were passive observers, not actual prosthesis users controlling the device. The task involved constant-velocity closing; real-world myoelectric control involves variable muscle signals which may alter feedback quality. The setup did not use cosmetic gloves, which are standard in clinical use and may dampen auditory and visual cues. The vibrotactile interface used a linear mapping; non-linear mappings might improve performance.
Declared interests
Funded by the German Federal Ministry of Education and Research and the Danish Independent Research Fund. No commercial conflicts were declared.
The easy way to misread this
Do not assume that incidental feedback works as well for experienced amputees controlling a prosthesis with variable muscle signals as it did for able-bodied observers watching a computer-controlled device.