Effects of neuromodulation on gait

In the last decades, non-invasive brain stimulation (NIBS) has evolved to become a valuable tool in both basic and clinical neuroscience. Various methods of transcranial magnetic stimulation (TMS) and transcranial electrical stimulation (TES) have been widely used for diagnostic, prognostic and even therapeutic applications in a broad range of neurological and psychiatric disorders. The rationale for using NIBS techniques lies in the possibility to modulate, in a targeted manner, the activity of different cerebral and cerebellar cortical regions, as well as the functional connections between these areas and distant brain regions also including subcortical structures. The neural circuitry involved in the different aspects of gait control is very complex and includes, along with the basal ganglia-cortical loops, the cerebellum and structures of the brainstem and the spinal cord. This is why different approaches of NIBS have been suggested for treatment of gait disorders in a variety of neurological disorders including Parkinson’s disease, stroke, cerebellar ataxia, multiple sclerosis, cerebral palsy and spinal cord injury. This review will collate the available knowledge on the physiology of gait and balance control, focusing on the ways in which the use of NIBS may contribute to the understanding and treatment of gait disorders.