The Effects of the Five Basic Tastes on Oral Transit Time for People with Dementia: An Extended Research Proposal

Abstract

Background: Tastes in differing concentration levels heightens sensory input to the cortical swallowing centres. Taste stimulation is an intervention for dysphagia management that introduces a taste into the mouth, in order to modulate the timing of the swallow. This dissertation considers taste stimulation as an intervention directed to help people with dementia with swallowing difficulties. People with dementia often experience difficulties with the voluntary phases of the swallow, resulting in slow or absent initiations of the swallow, leaving individuals malnourished, dehydrated and at high risk of developing aspiration pneumonia. Taste has been identified as a sensory factor that can be manipulated to stimulate an initiation of the swallow, resulting in fewer hospital admissions and better quality of life for individuals and their families. Purpose: This paper aims to identify the taste and concentration level that decreases the oral transit time for people with dementia. Methods: The effects of taste on oral transit time will be measured using Ultrasound Tongue Imaging. A small pilot study was undertaken to determine the feasibility of this method in measuring oral transit time and to identify methodological improvements for transferring the method to a dementia population. All five basic tastes were observed in the small study with three concentration levels for each taste. The results from the pilot study indicated that the bitter taste could be omitted from testing in the research proposal as it had no impact on the swallow. Conclusions: The research proposal hypothesises that the most effective taste and concentration level for people with dementia will be a highly concentrated sour bolus. The results will go some way to improving dysphagia interventions for people with dementia, by advocating for taste stimulation to become a mandatory early intervention for all individuals diagnosed with dementia.