Eating and Swallowing, Oral Health, and Saliva Production

Eating and maintaining optimal nutrition are essential to health and quality of life. In both health and disease, eating is influenced by multiple factors including swallowing, oral health, and saliva production. Perturbations to any, or all, of these inter-related factors may result in consequences that negatively affect the health and wellness of an individual. Eating and swallowing impairment are common symptoms of neurodegenerative diseases such as dementia, and these symptoms are associated with a host of negative sequelae such as malnutrition, dehydration, aspiration pneumonia, and reduced quality of life. The studies reported in this dissertation explored elements of eating and swallowing, saliva production, and saliva modulation in healthy individuals and in persons with Alzheimer’s disease (AD). This dissertation is composed of three studies. First, a scoping review methodology was used to examine literature that addressed autonomic nervous system and/or swallowing dysfunction in individuals with AD. Then, systematic review and meta-analysis methodologies were used to examine a potential effect of aging on saliva production. Finally, a within-subjects methodology was used to examine the modulation of salivary flow by tooth brushing in healthy older adults. In the first study, swallowing dysfunction and autonomic nervous system dysfunction, including salivary flow dysfunction, were found to occur in persons with AD. In the second study, salivary flow was found to be reduced in adults aged 60 years and older who were free of major systemic disease. In the third and final study, the use of manual and electric tooth brushing was found to increase whole salivary flow rates in adults aged 60 years of age and older who were free of major systemic disease. The results of this dissertation have very important implications for the future research and management of eating and swallowing, oral health, and saliva production in a variety of populations, including aging individuals and persons with AD

Active Learning and Student Achievement: A matter of space, experiences, or pedagogy?

The goal of this study was to contribute to research on active learning by addressing the problem of disentangling the effects of classroom architecture, student characteristics, and pedagogical design as they relate to student achievement. The study utilized a quasi-experimental design where data was collected on student perceptions of their classroom, their experience in the course, and the pedagogy of the instructor, then analyzed with respect to the course grade. Results indicate that student perceptions of the classroom spaces nor the spaces themselves had an impact on course grade, but the pedagogy employed by the instructor and student experiences did

Active Learning and Student Achievement: A matter of space, experiences, or pedagogy?

The goal of this study was to contribute to research on active learning by addressing the problem of disentangling the effects of classroom architecture, student characteristics, and pedagogical design as they relate to student achievement. The study utilized a quasi-experimental design where data was collected on student perceptions of their classroom, their experience in the course, and the pedagogy of the instructor, then analyzed with respect to the course grade. Results indicate that neither student perceptions of the classroom spaces nor the spaces themselves had an impact on course grade, but the pedagogy employed by the instructor and student experiences did

The Impact of Active Learning in a Speech-Language Pathology Swallowing and Dysphagia Course

The signature pedagogy in Speech-Language Pathology (SLP) higher education programs has been criticized for its instructor-centric lecture format and emphasis on the lower tiers of Bloom’s taxonomy (simply memorizing knowledge) at the expense of helping students develop the clinical problem-solving skills required for a lifetime of practice and learning. The purpose of this study was to examine the responses of a cohort of graduate speech-language pathology students to an active learning-oriented swallowing and dysphagia course design. A potential relationship between student perceptions of the active learning pedagogy and academic performance was also explored. The results suggest that active learning positively impacted both student perceptions and performance in the redesigned swallowing and dysphagia course

Altered salivary flow, protein composition, and rheology following taste and TRP stimulation in older adults

Taste and smell perceptions diminish in older age, impacting upon quality of life and nutrition, yet the causes of taste loss are largely unknown. Transient receptor potential channels (TRP) found on the oral mucosa are also involved in oral sensations including cooling and burning and may contribute to the eating experience of older people. Older adults often have reduced salivary flow and the physical properties of saliva may change, but the role of saliva in oral sensations of older adults is yet to be elucidated. Here, the effect of older age on subjective (perception) and objective (stimulated salivary response) measures of TRP stimulants, odors, and basic tastants was investigated. Whole mouth saliva was collected from younger (mean age 24 years) and older adults (mean age 72 years) following stimulation of taste [mono sodium glutamate (MSG) and caffeine], olfaction (menthol), and TRP receptors (capsaicin). Participants rated perceived intensity of each stimulus, and salivary properties were assessed. Older age was associated with 15% lower umami taste and 26% lower menthol odor perception, coupled with 17% lower salivary response to MSG. Interestingly, there were no differences for perception of TRP stimulants, so chemo-sensation was not affected by age. Younger adults had four times greater elasticity (Spinnbarkeit) with MUC7 levels almost double and 66% greater resting salivary flow rate. Stimulated salivary responses in the younger group were also higher compared to the older group, with changes in protein and viscoelasticity in response to taste and TRP stimulation. These results show the impact of older age upon taste and smell sensation which may lead to changes in the physical and compositional properties of saliva in response to taste/odor stimulation. Measurement of stimulated salivary flow and rheology provides an objective measure of taste in addition to subjective perceptions which can be influenced by participant bias. Chemo-sensation may be retained with age and trigeminal stimuli such as chili could be employed in future studies to enhance meals for an age group at risk of malnutrition. Alteration in salivary properties due to advanced age could impact on ability to taste due to poor diffusion of tastants and reduced oral surface protection

Scoping review of methods for engaging long-term care residents living with dementia in research and guideline development

Objectives To describe: (1) methods used to engage long-term care (LTC) residents living with dementia in research and guideline development; (2) the outcomes of engagement; and (3) barriers and facilitators to engagement.Design Scoping review.Search strategy We conducted searches in Academic Search Premier (EBSCO), APA PsychInfo (EBSCO), CINAHL (EBSCO), Medline (OVID), Embase (Elsevier), Web of Science and the Cochrane database, and a structured grey literature search in July 2021 and updated in March 2023. We included studies that described or evaluated resident engagement, defined as including residents living with dementia in the process of developing healthcare guidelines or research which could include collaborators or partners in planning, execution or dissemination of the guideline or research. Title, abstracts and full-texts were screened for eligibility by two team members using a pilot-tested process. Data were extracted from included studies independently and in duplicate by two team members using a pre-tested data extraction form. Results were narratively synthesised according to the research question they addressed.Results We identified three studies for inclusion. Residents were engaged at the beginning of the research projects through interviews, focus groups, and consultations. None of the included articles described the outcomes of engagement. Barriers to engagement were predominantly at the resident level, including impaired verbal communication limiting resident’s abilities to participate in discussions, while increased time to support engagement was reported as a barrier at the resident and research team levels.Conclusions We found a small body of literature describing the engagement of LTC residents in health research and guideline development. Future work should explore alternative methods to engage LTC residents living with dementia, including art-based methods, and the effect of including resident engagement. Guideline developers and researchers should ensure adequate time and human resources are allocated to support engagement

The Effects of Tooth Brushing on Whole Salivary Flow Rate in Older Adults

Objectives. (1) To determine whether manual (MTB), or electric, tooth brushing (ETB) modulates whole salivary flow rate in older adults who are free of systemic disease. (2) To determine the duration of the brushing-related modulation of salivary flow rate. (3) To compare salivary flow rate modulation associated with MTB and ETB. Method. Twenty-one adults aged 60 years and older participated in two experimental sessions during which they used a manual, or electric, toothbrush to brush their teeth, tongue, and palate. Whole salivary flow rates were determined using the draining method before, during, and after brushing. Differences in salivary flow rates across time periods, and between conditions, were examined using paired samples t-tests applying a Holm-Bonferroni sequential procedure (pcorr<0.0045). The relationship between tooth brushing and age with respect to maximum salivary flow rate increase was examined using Pearson’s correlation coefficient (p<0.05). Results/Conclusion. Whole salivary flow rates increased during, and for up to 5 minutes following, tooth brushing in adults aged 60 years and older who were free of systemic disease. The salivary effects of MTB and ETB were not significantly different. A moderate, positive correlation was observed between tooth-brushing-related maximum salivary flow rate increase and age