The lab uses principles of neuroscience, engineering and mathematics to assess emerging prosthetic devices and to direct their improvement. This work started as part of a large project that aimed to provide upper-limb amputees with more capable prostheses by directly connecting devices with nervous systems. Being able to measure prosthesis system performance is important to direct improvements in the lab and track patient progress in clinical settings.
The Control Bottleneck Index
One assessment we have developed is the Control Bottleneck Index (CBI) which aims to separately assess the quality of the control system, sensory feedback, and training regimen to help biomedical engineers target improvements to the weakest link in their systems. In this work we use mathematical methods to simulate the human nervous system and solve for theoretical parameters of interest using empirical data.
We are also working on several assessments to measure aspects of limb embodiment, i.e. how a limb (real, prosthetic or virtual) becomes considered a part of one's own body. Improving limb embodiment is thought to be important in improving the acceptance and utility of prosthetic devices. As we try to move away from subjective self-report surveys to measure embodiment, we have developed psychophysical methods to measure specific aspects of embodiment, including ownership and agency.
Cognitive load and attention assessments
To broaden our assessment toolkit we are using brain activity recordings (electroencephalography, or EEG) as an indicator of cognitive load. We are trying to use a certain type of detected brain activity (alpha waves) to measure, in real time, how much mental processing is occurring. We hope to use this to test out prosthetic devices and quickly identify when new systems are overlying taxing on mental resources. Using cameras to measure eye gaze direction, we are also incorporating attentional information into our prosthesis assessments. Where a person focuses their attention gives us clues as to how much trust a person has in the limb they are moving.