Directional Sensitivity of the Proprioceptive Sense of Force

Normal movements are generated via controlled activation of motor units (MUs), which consist of motoneurons and their innervated muscle fibers. To support the wide range of movements humans perform daily, its been suggested that MUs are recruited and fire depending on the direction of applied force. The proprioceptive sense of force, which is the ability to accurately sense and reproduce a given force, is essential for successful movement, yet becomes impaired with aging, injury, or neuromuscular disorders, making everyday tasks difficult or impossible. Recent work has assessed how force sense changes with age and motoneuron excitability, however, these studies were limited to simple joint movements. Therefore, this project aims to analyze how multidirectional MU behaviours contribute to force sense, so that findings can be directly applied functionally, such as within rehabilitation programs. To do this, we will use high-density surface electromyography to record muscle activity from the deltoid during force reproduction tasks, where participants match forces in either the same or different directions. Data will be collected using an end-point controlled robotic arm attached to a load cell. The collaboration between the two laboratories will combine complementary expertise, strengthen a pre-existing partnership, and support future joint-publications and training opportunities.

Faculty Supervisor:

Greg Pearcey

Student:

Partner:

University of Brescia

Discipline:

Life Sciences

Sector:

Health and Related Sciences & Technology

University:

Memorial University of Newfoundland

Program: