Enhancing Corticospinal Activation for Improved Walking Function
Condition: Spinal Cord Injuries
MeSH terms: Spinal Cord Injuries
Study type: Interventional

Summary: 
      For many people with spinal cord injury (SCI), the goal of walking is a high priority. There
      are many approaches available to restore walking function after SCI; however, these
      approaches often involve extensive rehabilitation training and access to facilities,
      qualified staff, and advanced technology that make practicing walking at home difficult. For
      this reason, developing training approaches that could be easily performed in the home would
      be of great value. In addition, non-invasive brain stimulation has the potential to increase
      the effectiveness of communication between the brain and spinal cord. Combining motor skill
      training with brain stimulation may further enhance the restoration of function in persons
      with SCI. Based on these findings, the primary aim of this proof-of-concept study is to
      inform future intervention development. To meet this aim, we will determine if
      moderate-intensity, motor skill training can improve walking-related outcomes among persons
      with SCI and to determine if the addition of non-invasive brain stimulation will result in
      greater improvements in function compared to training alone.
    

Detailed description: 
      For many people with spinal cord injury (SCI), the goal of walking is a high priority. There
      are many approaches available to restore walking function after SCI; however, these
      approaches often involve access to intensive training programs, facilities, qualified staff,
      and advanced technology that make practicing walking at home difficult. For this reason,
      developing training approaches that could be easily performed in the home would be of great
      value. In addition, research suggests that enhancing brain excitability might have benefits
      for improving the communication between the brain and spinal cord. Transcranial direct
      current stimulation (tDCS) is a type of non-invasive brain stimulation that has been shown to
      directly increase brain excitability, which may make it easier for the brain and nervous
      system to respond to training. Combining motor skill exercises with brain stimulation may
      enhance the restoration of walking function in persons with SCI. Based on these findings, the
      primary aim of this proof-of-concept study is to inform future intervention development. To
      meet this aim, we will determine if moderate-intensity, motor skill training can improve
      walking-related outcomes among persons with SCI and to determine if the addition of
      non-invasive brain stimulation will result in greater improvements in function compared to
      training alone.

      Participants in the proposed study will complete one baseline testing session, 3 motor
      training sessions, and one follow-up session over 5 consecutive days. During the first and
      fifth sessions, participants will complete assessments only, which will take approximately
      2-3 hours each day. During the second, third, and fourth sessions, participants will perform
      a series of 6 standing motor skill exercises designed to challenge balance, lower extremity
      coordination, agility, and speed. Participants will be randomized to either a motor training
      only group or a motor training + tDCS group. The motor training + tDCS group will receive
      brain stimulation during the motor skill training, while the motor training only group will
      receive sensory level brain stimulation only. Each participant will complete the 6 motor
      skill exercise circuit 4 times. Motor training exercise sessions will last approximately
      25-30 minutes and will be preceded and followed by assessments of walking function,
      spasticity, and ankle strength in order to determine changes in these measures over time.
    

Intervention name(s): Motor Skill Training; Transcranial direct current stimulation (tDCS)
Intervention type(s): Other; Device
Intervention description(s): Motor skill training will consist of activities that will be performed while standing to promote upright control (the toe-tapping activity will be performed while seated). Participants will perform each of the 6 different activities for one minute each, until 4 cycles of the circuit have been completed (approximately 25 minutes total). Motor training activities will be performed at an intensity of 40-59% of heart rate reserve (HRR). Toe tapping will provide the opportunity for scheduled rest. During MT, all participants will wear a heart rate monitor to ensure that the optimal HR range is achieved. HRR will be calculated from resting and peak heart rate measures obtained during baseline testing via administration of a graded-exercise test.; The tDCS electrode placement is based on procedures shown to improve gait and balance in a single session when used in combination with gait training activities. tDCS electrodes can simultaneously activate the bilateral leg motor areas when placed at the midline of the scalp slightly anterior to the vertex (anode) and at the inion (cathode), with a current intensity of 2mA. The tDCS device is lightweight, and can be worn in a backpack during the MT activities. As reported previously, participants in the MT-only group will receive sham tDCS to maintain analogous study procedures.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Triple (Participant, Investigator, Outcomes Assessor)
Primary purpose: Treatment