Assessment of Brain Inhibitory Function in Physical Therapy

Abstract

Interhemispheric inhibition is an inhibitory function of the brain that enables complex human locomotion and plays an important role in motor control. Traditionally, interhemispheric inhibition has been assessed using transcranial magnetic stimulation, functional magnetic resonance imaging, and electroencephalography. However, motor overflow and bimanual coordinated movements have recently attracted attention as behavioral indices involving interhemispheric inhibition. Motor overflow is defined as the presence of involuntary movements or weak muscle activity that appears with voluntary movements and has been found to occur mainly in the elderly, children, and those with central nervous system diseases. In addition, interhemispheric inhibition is involved in bimanual coordinated movements associated with interhemispheric motor control and information processing. This chapter outlines motor overflow and bimanual coordinated movements as new behavioral indices of interhemispheric inhibition and proposes assessment methods that can be performed in physiotherapy clinics.