Brain Change Following Swallowing Skill Training in Patients with Parkinson's Disease

This exploratory pilot study will investigate neurological change following a period of swallowing skill training for patients with dysphagia (swallowing disorder) secondary to Parkinson’s disease. Eight participants will engage in a four-week period of swallowing skill training, completed predominantly in their own homes, using the Biofeedback in Strength and Skill Application (BiSSkApp [Registered Trademark]) to deliver the training. Brain imaging assessment will include magnetic resonance imaging (MRI) and electroencephalography (EEG). MRI will be conducted at two timepoints: pre- and post-training, approximately four weeks apart. These scans will be conducted by qualified MRI technologists employed by Pacific Radiology and will not require administration of any dyes or contrast. Each scan will take up to 1.5 hours, including setup time. Electroencephalography will be conducted by the primary researcher at three timepoints concurrently with training: during the first, third, and final skill training sessions. It is anticipated that these sessions will take up to two hours each, including setup time. Swallowing skill training is a rehabilitation approach that aims to improve swallowing at the central level, by targeting motor control and coordination. Surface electromyography (sEMG) overlaying the participant’s floor of mouth muscles (i.e., under their chin) detects muscle activation during swallowing. This activity is presented as a live time-by-amplitude waveform that is displayed on a tablet screen, effectively allowing participants to see a visual representation of their swallowing behaviour. Participants use this waveform as a biofeedback tool to volitionally modulate temporal and amplitude elements of their swallowing (i.e., muscle timing and force) to “hit” a target box positioned in unexpected locations on the tablet screen with each trial. Introduction to and support with the intervention will be provided by a qualified speech-language therapist. The introductory session for the training will take place in a research centre setting and involve the aforementioned concurrent EEG recording, which may take up to two hours, including setup time. Participants will complete up to 100 swallowing skill training trials per day (i.e., approximately 1 hour per day, five days per week, for four weeks). Most training sessions will be completed in participants' own homes and time, except for the first, third, and final sessions, which will be conducted in a research centre setting. It is acknowledged that an intensive therapy block such as this may be challenging for individuals who may be experiencing continuing effects of neurological disease such as fatigue. As such, this planned intensity may be modified according to individual needs. For example, a participant may break the swallowing trials into smaller sessions (e.g., five sessions of 20 swallows). Total number of trials per day may also be reduced if necessary, but, again, this will be determined on an individual basis through a clinical, patient-centred lens, with participants maintaining the maximum number of trials they can tolerate. The primary researcher will check in with participants once per week (via their preferred modality, e.g., telephone) to evaluate how they are finding the training and to make adaptations as needed. The researcher will also monitor the participant’s adherence to the training programme via a remote clinician portal and, if training sessions are missed, will contact them to discuss reasons for this and to troubleshoot. Additionally, patients will be able to contact the research team to discuss any issues or questions they may have relating to the research or training.