The Effect of Nervus Vagus Stimulation on Spasticity, Autonomic Function, Motor Function and Quality of Life in Children With Spastic Cerebral Palsy

Introduction: Cerebral palsy (CP) is a heterogeneous neurodevelopmental syndrome affecting muscle tone, motor skills, and movement due to brain injury during developmental stages. The etiology of CP is associated with factors such as prematurity, low birth weight, and pregnancy or birth complications. The spastic type is the most common motor disorder, characterized by increased reflexes and muscle hypertonia in the extremities. Spasticity arises from upper motor neuron lesions, leading to dysregulation in spinal and brain pathways (corticospinal, reticulospinal, vestibulospinal) and involves complex modulation of muscle tone and stretch reflexes. The autonomic nervous system regulates visceral functions, while the vagus nerve, through its parasympathetic fibers, exerts widespread influence on the heart, respiratory system, and gastrointestinal system. It controls organ function via motor, sensory, and parasympathetic fibers originating from three medullary nuclei (nucleus ambiguus, dorsal motor nucleus, and nucleus solitarius). Vagus nerve stimulation (VNS) modulates the central nervous system by stimulating afferent fibers, increasing GABA and other inhibitory neurotransmitter levels, reducing excitatory signals, and potentially influencing spasticity. VNS can be applied invasively or non-invasively (transcutaneous VNS, tVNS); particularly, tVNS applied to the left ear is a safe and well-tolerated method with therapeutic potential in epilepsy and motor disorders. This study aims to investigate the effects of non-invasive auricular vagus nerve stimulation (taVNS) combined with the Bobath approach on motor function, autonomic function, spasticity, activities of daily living, and quality of life in children with spastic cerebral palsy (CP). Materials and Methods: Planned as a prospective, controlled study, children with CP will be randomly assigned to two groups. The intervention group will receive the standard Bobath program administered by physiotherapists wit