Combining theta burst stimulation with training after subcortical stroke.

Area of Science:

• Neuroscience
• Rehabilitation Medicine
• Neurology

Background:

• Stroke frequently causes upper-limb impairment.
• Repetitive transcranial magnetic stimulation (TBS) of the primary motor cortex (M1) is a potential therapeutic approach.
• Understanding the effects of different TBS protocols on motor recovery is crucial.

Purpose of the Study:

• To investigate the impact of M1 theta burst stimulation (TBS) combined with motor training on upper-limb function in chronic stroke patients.
• To compare the effects of intermittent TBS of the ipsilesional M1, continuous TBS of the contralesional M1, and sham TBS.

Main Methods:

• A double-blind, crossover, sham-controlled study involving ten chronic stroke patients with upper-limb impairment.
• Delivery of intermittent TBS (ipsilesional M1), continuous TBS (contralesional M1), and sham TBS in separate sessions.
• Standardized precision grip task training using the paretic upper limb.

Main Results:

• Training post-real TBS enhanced paretic hand grip-lift kinetics; training post-sham TBS led to deterioration.
• Intermittent TBS of ipsilesional M1 increased M1 excitability; continuous TBS of contralesional M1 decreased it.
• Action Research Arm Test scores declined after continuous TBS of contralesional M1, linked to reduced ipsilesional corticomotor excitability.

Conclusions:

• Theta burst stimulation (TBS) and training generally yielded task-specific improvements in grip-lift.
• Continuous TBS of the contralesional M1 resulted in a functional decrement, suggesting its critical role in stroke recovery.
• The contralesional hemisphere appears pivotal for functional recovery post-stroke.