Skill versus Strength in Swallowing Training: Neurophysiological, Biomechanical, and Structural Assessments [article]

Oshrat Sella, University Of Canterbury
2013
Swallowing is a complex sensorimotor behaviour that includes precisely-timed bilateral activation and relaxation of muscles of the face, lips, tongue, cheeks, palate, larynx, pharynx and oesophagus. These events of activation and inhibition are controlled by many structures of the brain and are executed by cranial nerves that carry motor and sensory information to and from the swallowing muscles. Swallowing disorders are common sequelae of many neurological and structural disorders, including
more » ... roke, Parkinson's disease, and head and neck cancer. Changes to swallowing physiology are also prevalent in older individuals, but these changes do not necessarily translate to dysphagia. Decreased muscle strength, changes to motor unit properties, and hypotrophic changes in skeletal muscles can result in age-related changes in swallowing physiology. In addition to muscular changes, neural changes might also change swallowing function in older subjects. The motor-learning literature presents a clear distinction between the differential applications and effects of skill- and strength-training approaches for rehabilitation of limb movement. In contrast to limb-movement rehabilitation, swallowing rehabilitation approaches consist mainly of strength training, although the pathophysiological basis for dysphagia is not always weakness. Therefore, this Phase I clinical-trial critically evaluated a unique swallowing skill training protocol in which the goal of intervention is to increase precision of motor control during swallowing. A Phase I clinical-trial was necessary to identify the appropriate protocol for inducing neurophysiological, biomechanical, and structural adaptations, to estimate effect sizes, and to identify adverse effects. The first and primary question addressed in this thesis was whether swallowing skill training would produce greater physiological effects in healthy subjects than a traditional swallowing strength training approach. In order to answer this question, three levels of assessment were included. Neur [...]
doi:10.26021/7530 fatcat:twrxh35wzbbpfb6bqggcl4zh2q