Investigating the effect of a computer-based training program on swallowing-related quality of life, swallowing function and the power and precision of swallowing for adults with chronic dysphagia.

A relatively new computer-based training program, called Biofeedback in Strength and Skill Training (BiSSkiT), was developed by Professor Maggie-Lee Huckabee at the Rose Centre for Stroke Recovery and Research, University of Canterbury, Christchurch, New Zealand. BiSSkiT comprises a training protocol and accompanying software program, with surface electromyography as the underlying hardware, for the rehabilitation and outcome measurement of swallowing impairments. The BiSSkiT software will be loaded onto a computer and the BiSSkiT intervention provided face-to-face on a one-to-one basis by one of main investigators. The BiSSkiT intervention involves application of surface electrodes under the chin, allowing measurement of the activity of the floor-of-mouth muscles (mylohyoid, geniohyoid, genioglossus and anterior belly of diagastric) that are involved in anterior hyoid excursion (the movement of the hyoid bone by the muscles during the pharyngeal phase of a swallow). The activity arising from the floor-of-mouth muscles is fed into a computer program that generates real-time amplitude waveform images on the computer screen and provides visual and auditory feedback. The program is aimed at increasing both strength and the precision of muscle contraction, thus providing the necessities of motor learning to drive neural change (e.g. high intensity and high repetition; clear visual waveform display to monitor and adapt task performance; feedback that is adapted to patient performance to increase task challenge; a variety of audio and visual feedback to maintain interest and motivation). For example, to increase strength the display highlights the maximal contraction achieved and provides visual and auditory feedback to achieve this on repeated occasions and, over time, increase the strength of the contraction. To improve the precision of muscle contraction, the program prompts the user to generate a pre-determined sub-maximal contraction at a set time. The BiSSkiT program uses images, such as a bee (whose movement across the computer screen is the trace of the muscle contraction) buzzing into a flower (which is the desired maximal or sub-maximal contraction). The difficulty of BiSSkiT tasks is increased or decreased depending on each persons’ response and individually tailored to meet his/her training requirements. The interventions are each of one hour’s duration, provided three times a week, for a total of 10 interventions. Thus, the intervention period will last 4 weeks. A log book will be kept to document adherence with session attendance.