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Non-Invasive Electrical Stimulation Treatment for Spinal Cord Injury Patients and its Effect on Recovery Time Lauren Wehausen Spinal cord injuries can be severe and life-altering. Such injuries can leave patients paralyzed or partially paralyzed. Such trauma is typically treated through invasive techniques such as surgery, as well as with medications. The problem with such techniques is that they pose risk for the patient—such invasive procedures can cause more damage, death, and do not specifically target the motor-control injury. New research has begun with non-invasive techniques – through electrical stimulation – that can help restore/improve patients’ impaired mobility. In the research article “Corticospinal-motor neuronal plasticity promotes exercise-mediated recovery with humans with spinal cord injury” researcher Dr. Monica Perez explores how using non-invasive electrical stimulation at spinal synapses, in conjunction with exercise [therapy], quickens the recovery rate for spinal injury patients. (As compared to those doing exercise alone). Corticospinal-motor neuronal stimulation (PCMS) and sham-PCMS, the non-invasive stimulation and the placebo treatment, were paired with exercise as the plan of treatment for twenty-five individuals, all with chronic incomplete injuries to the cervical, thoracic, and lumbar spinal cord. Thirteen other individuals with similar spinal-cord injuries were tested in a PCMS-alone, to compare the results between the two. All thirty-eight individuals were randomly assigned to one of the three groups. The three groups, exercise paired with PCMS, exercise paired with sham-PCMS, and PCMS alone, each completed ten sessions of their designated treatment. During the sessions, muscle stimulation was measured with MEP, motor evoked potentials, each around 50% of the MEP-max amplitude. EMG activity was used to record maximal voluntary contraction (MVC). For both the PCMS-with-exercise and PCMS-alone groups, MEP and MVC both increased; however, in the sham-PCMS group, no significant change was observed. Six months post-experiment, particpants were invited back to be reassessed. Upon reassessment, Perez found that the results remained the same for both groups that received PCMS treatment but that performance decreased in the sham-PCMS (control) group. This study exemplifies the potential that non-invasive stimulation has for spinal-injury patients when paired with exercise. This method was successful in terms of increased motor control performance. In a similar experiment, Freyvert et al., studied cervical electrical stimulation with and without combination with monoaminergic buspirone on upper limb function in patients with motor complete injury. In this study, upper limb function was assessed by measuring handgrip force, controlled hand contraction, and dexterity of six patients with spinal cord injuries at C5 or higher. Particpants were told that they would either receive oral buspirone, a neurotransmitter involved in locomotor function, or a placebo (in conjunction with the electrical stimulation). Electrical stimulation was conducted with electrodes placed on the dorsal side of the neck on the C5 vertebra. Performance was measured during nine maximum-handgrip strength tests; EMG was used to record the data. The mean grip strength across all six participants improved after each wave of treatment. This study indicates that a combination of stimulation and pharmacological treatment increases motor functionality in upper limbs Both studies used non-invasive stimulation of the spinal cord, albeit at different areas, to enhance or regain motor functionality. In Dr. Perez’s study, PCMS proved to enhance the recovery time in patients with spinal cord injuries, during the study and six-months post-experiment. Similarly, in the study by Freyvert et al., patients expressed increased volitional motor hand function ability post-electrical stimulation treatment. These two studies leave further research to be conducted on the extent of this treatment’s success. Non-invasive, spinal cord electrical stimulation treatment may have future use in the treatments of spinal cord injury patients and those suffering from other neural, motor-debilitating diseases. Citations Freyvert, Y., Yong, N.A., Morikawa, E. et al. Engaging cervical spinal circuitry with non- invasive spinal stimulation and buspirone to restore hand function in chronic motor complete patients. Sci Rep 8, 15546 (2018). https://doi.org/10.1038/s41598-018-33123-5 Hang Jin Jo, Monica A Perez, Corticospinal-motor neuronal plasticity promotes exercise- mediated recovery in humans with spinal cord injury, Brain, Volume 143, Issue 5, May 2020, Pages 1368–1382, https://doi.org/10.1093/brain/awaa052