The Cortical Motor Effects of PNS and AO on Motor Training in Chronic Stroke
Condition: Stroke
MeSH terms: Stroke
Study type: Interventional

Summary: 
      This study aimed to investigate if peripheral nerve stimulation (PNS) paired with action
      observation (AO) would augment motor training in promoting corticomotor excitability for the
      paretic hand in people with stroke. Twenty subjects in chronic stage of stroke were exposed
      to 3 different interventions involving one-hour PNS or sham PNS paired with 30 minutes of AO
      or sham AO, all followed by 30 minutes of finger abduction training in 3 separate sessions.
    

Detailed description: 
      The investigator's previous study (Liu & Au-Yeung, 2017; PMID: 28383292) has demonstrated
      that 1-hour peripheral nerve stimulation (PNS) applied to the radial and ulnar nerves of the
      paretic UL of people with chronic stroke can increase transcranial magnetic stimulation
      (TMS)-evoked excitability of corticomotor pathways in both hemispheres projected to the
      contralateral first dorsal interosseous (FDI) hand muscle, and also improve dexterity in the
      paretic hand. This bi-hemispheric effect of PNS suggests that certain additional therapies
      such as action observation (AO) and motor training should be incorporated to strengthen the
      plastic corticomotor adaptation specifically for paretic UL control. The hypothesis of this
      study is that PNS paired with AO would augment task training of the paretic hand by
      increasing the corticomotor excitability in the lesioned hemisphere for the trained hand
      muscle in people with stroke, with associated dexterity function improvement. Twenty subjects
      were recruited by convenience in the community. They then attended an assessment session to
      evaluate the baseline sensorimotor status of their paretic upper limb. After the clinical
      tests，the subjects were introduced the assessment procedure for measuring corticomotor
      excitability with transcranial magnetic stimulation (TMS). After 1-week intermission, the
      subjects returned for 3 intervention sessions with different protocols including
      (1)PNS+AO+Training; (2)PNS+AOsham+Training; and (3)PNSsham+AOsham+Training. These 3
      intervention sessions were arranged in random sequence for subjects. For "PNS+AO+Training"
      session, electrical stimulation was applied to the radial and ulnar nerve (PNS) of the
      paretic arm for 60 minutes. During the last 30 minutes of PNS, action observation (AO) was
      introduced in which subjects were required to watch a series of video clips. After one hour's
      PNS+AO, the subjects then proceeded to a 30-minute period of motor training of paretic hand.
      During "PNS+AOsham+Training" session, PNS was given as described before. During the last 30
      minutes of the PNS, subjects were shown different photos illustrating a letter, a number or a
      hand as AOsham. The protocol of motor training was the same as described before. In the
      session of "PNSsham+AOsham+Training", The 1-hour PNSsham was conducted with the electrical
      stimulation unit turned on but without current output. The protocols for AOsham and motor
      training were the same as those described before.
    

Intervention name(s): PNS+AO+Training; PNS+AOsham+Training; PNSsham+AOsham+Training
Intervention type(s): Genetic; Genetic; Genetic
Intervention description(s): Electrical stimulation was applied to the radial and ulnar nerve (PNS) of the paretic arm for 60 minutes. During the last 30 minutes of PNS, action observation (AO) was introduced in which subjects were required to watch a series of video clips. After one hour's PNS+AO, the subjects then proceeded to a 30-minute period of motor training of paretic hand.; PNS was given as described before. During the last 30 minutes of the PNS, subjects were shown different photos illustrating a letter, a number or a hand as AOsham. The protocol of motor training was the same as described before.; The 1-hour PNSsham was conducted with the electrical stimulation unit turned on but without current output. The protocols for AOsham and motor training were the same as those described before.
Allocation: Randomized
Intervention model: Crossover Assignment
Intervention model description: Single-blind randomized cross-over study
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: Electrical Stimulation; Cortical Excitability; Transcranial Magnetic Stimulation