Kinesthetic illusions induced by muscle tendon vibration: The orientation of the vibration motor as a new methodological factor?

Results from the present study demonstrated that the rotational orientation can influence illusory perceptions, but not to a great extent. Distoproximal rotation was more effective to elicit the expected illusions of wrist extension, compared to the lateromedial orientation that more often caused complex and variable perceptions of movement. Distoproximal rotation should thus be preferred if clear and reproducible perceptions are required and lateromedial might serve as a way of creating illusions more akin to everyday functional movements. Although the exact underlying mechanisms remain unclear, our work raises awareness on the importance of gaining a better understanding and control over methodological factors that could affect kinesthetic illusions.