Affiliations: [a]
Department of Psychology, University of Rome “Sapienza”, Rome, Italy
| [b] IRCCS Fondazione Santa Lucia, IRCCS, Rome, Italy
| [c]
Hospital A.Alesini C.T.O., Unipolar Unit, Rome, Italy
Correspondence:
[*]
Corresponding author: G. Fusco and E. Tidoni, Department of Psychology, “Sapienza” University of Rome, via dei Marsi 78, 00185, Rome, Italy. Tel.: +39 06 49917635; Fax: +39 06 49917635; E-mails: [email protected] (G. Fusco); [email protected] (E. Tidoni).
Abstract: Background: Studies in healthy people show that stimulation of muscle spindles through frequency-specific tendon vibration (TV) induces the illusory perception of movement. Following spinal cord injury (SCI), motor and sensory connections between the brain and parts of the body below-the-lesion level are partially or totally impaired. Objective: The present investigation is a descriptive study aimed to investigate whether people living with SCI may experience movement illusions comparable to a control group. Methods: Healthy and people with SCI were asked to report on three illusion-related features (Vividness, Duration, Illusory Extension) after receiving 70 Hz TV on the biceps brachii tendon of both arms. Two different forces of stimulation were applied: 2.4 N and 4.2 N. Results: Both patients and controls were susceptible to the kinesthetic illusion. However patients presented lower sensitivity to TV than healthy subjects. Participants rated stronger illusions of movement after 4.2 N than 2.4 N stimulation in all the three illusion-related features. Further, patients reported atypical illusory experiences of movement (e.g. as if the arm wanted to extend, or a sensation of pushing against something) that may reflect different reorganization processes following spinal cord injury. Conclusion: The study provides a preliminary evidence of the possible use of the proprioceptive stimulation in the upper limbs of people living with SCI. Results are discussed in the light of recent advancements of brain-computer applications based on motor imagery for the control of neuroprosthetic and robotic devices in patients with severe sensorimotor deficits.
