Masters Applied Projects

Project 8

High-density EMG Analysis of Individual Motor Unit Activation in Multi-finger Force Production

Student: Chase Frailey

Mentors: Dr. Marco Santello – SBHSE
Dr. Claire Honeycutt – SBHSE
Dr. Stephen Helms Tillery – SBHSE

YouTube Link: View the video link below before joining the zoom meeting

Zoom link: https://asu.zoom.us/j/87246382893

Time: 10am – 2pm

Abstract

It is not yet known how the activity of motor units is coordinated among finger muscle compartments. High-density surface electromyography (sEMG) is a tool that allows for noninvasive spatial and temporal analysis of individual motor units. Using an array of closely spaced electrodes placed on the skin over a muscle of interest, sEMG in combination with decomposition algorithms can provide information about the firing patterns of individual motor units during tasks involving dynamic and static force. This technology allows for the investigation of the neural control of movement with potential clinical applications, i.e., diagnostics and rehabilitation of sensorimotor function. Here, sEMG is used to understand how motor units are recruited and coordinated when performing individual finger force tasks. A Quatrocentro amplifier (OT Bioelettronica) was used to collect EMG data from the Flexor Digitorum Superficialis muscle while participants performed cyclic or constant flexion of the middle and index fingers. Individual motor units were subsequently decomposed and visualized with a combination of OTBioLab and a decomposition MATLAB package. From the preliminary data, the temporal activation profiles of individual motor units and the spatial distribution of these motor units provide detailed information on the coordination of motor unit activity underlying control of the middle and index finger flexion movements. Further exploration with more finger combinations should lead to a better understanding of the neural factors that limit finger force independence and tools to improve dexterous finger force control.