Date of Award


Degree Type

Creative Project

Degree Name

Master of Science (MS)


Kinesiology and Health Science

Committee Chair(s)

David Bolton


David Bolton


Eadric Bressel


Chris Dakin


Observation of objects in our environment can potentiate movement, a fact reflected by increased activity in motor cortical networks when participants simply view a graspable object. This suggests that specific areas in the motor cortex play an important role in processing visual information to rapidly determine an appropriate action. The present study was conducted to test if visual access to a wall-mounted safety handle results in activation of motor cortical networks. We hypothesized that the hand area of the primary motor cortex would be facilitated shortly after visual access to a safety handle versus when no handle was visible. To test this, we used transcranial magnetic stimulation (TMS) to measure corticospinal excitability (CSE) in hand muscles immediately after visual access while participants performed a seated reach-to-grasp task. Vision was controlled using liquid crystal lenses and TMS pulses were time-locked to occur shortly after the goggles opened but prior to movement. During visual occlusion, the environment was unpredictably changed to present either a handle or no handle (i.e. covered). Our results showed a rapid motor facilitation in muscles of the right hand when participants viewed a handle compared to trials where this handle was covered. These findings suggest a rapid engagement of muscles specific to grasping a handle based on visual access to the handle. The fact that this affordance effect was present for a wall-mounted safety handle has implications for automatically priming recovery actions based on our surroundings, even without awareness of an imminent fall.

Included in

Motor Control Commons