Preconditioning with low frequency rTMS over right motor cortex (M1) influences the effect of intermittent Theta Burst Stimulation on excitability over left M1

Introduction: Theta Burst Stimulation (TBS) is a novel non-invasive method of conditioning the human motor cortex (M1) that can induce bidirectional changes in corticospinal excitability depending on the choice of stimulus parameters. However, several previous human studies provided evidence that the outcome of non-invasive brain stimulation depends on the previous history of neural activity. These findings indicate that homeostatic plasticity in human M1 might be one important physiological mechanism for the regulation of corticospinal excitability. While homeostatic plasticity has been demonstrated within M1 o…