The effect of taste on swallowing function

This study investigated the effects of taste on swallowing frequency and cortical activation in the swallowing network. The effects of salivary flow and taster status were also examined, along with genetic taster status. The effects of a 3ml bolus compared sour, sour with slow infusion, sweet, water, and water with infusion. Swallowing frequency was significantly higher 0-15 seconds after bolus delivery than 16-30 seconds. Swallowing frequency was higher in the sour conditions, whereas sweet and water did not differ. Functional near-infrared spectroscopy recordings measured changes in blood oxygenation (HbO) in the right and left hemispheres in the premotor, S1 and supplementary motor area in response to swallowing a bolus indicated a significant interaction of side and channel. Event-related analyses of HbO following bolus administration of taste solutions were significantly higher in the sensory than the premotor area in the right hemisphere. A block average analysis of the response to taste between 17 and 22 seconds after bolus administration revealed significant differences between hemispheres and regions. Genetic taster status was not significant in any of the analyses. The highest activation in response to sour taste was in the premotor regions of both hemispheres. The results indicated that sour taste effectively increased swallowing frequency and cortical activation while increasing salivary flow in comparison to water and sweet taste. In conclusion, sour taste may have peripheral effects on salivary flow while up-regulating the activation of the swallowing network at the cortical level

The effect of taste on swallowing: A scoping and systematic review

Consuming foods and liquids for nutrition requires the coordination of several muscles. Swallowing is triggered and modified by sensory inputs from the aerodigestive tract. Taste has recently received attention as a potential modulator of swallowing physiology, function, and neural activation; additionally, taste impairment is a sequela of COVID-19. This review presents factors impacting taste and swallowing, systematically summarizes the existing literature, and assesses the quality of included studies. A search was conducted for original research including taste stimulation, deglutition-related measure(s), and human participants. Study design, independent and dependent variables, and participant characteristics were coded; included studies were assessed for quality and risk of bias. Forty-eight articles were included after abstract and full-text review. Synthesis was complicated by variable sensory components of stimuli (taste category and intensity, pure taste vs. flavor, chemesthesis, volume/amount, consistency, temperature), participant characteristics, confounding variables such as genetic taster status, and methods of measurement. Most studies had a high risk of at least one type of bias and were of fair or poor quality. Interpretation is limited by wide variability in methods, taste stimulation, confounding factors, and lower-quality evidence. Existing studies suggest that taste can modulate swallowing, but more rigorous and standardized research is needed

Gender Diversity Cultural Responsiveness Education in Speech-Language Pathology Graduate Programs: A Pilot Survey

Purpose: Gender-affirming voice therapy aims to align a person’s voice and communication with their gender identity. Historically, transgender and gender-nonconforming (TGNC) individuals have been marginalized and continue to face significant healthcare disparities. The goal of this research was to examine the self-perceived preparedness of recent speech-language pathology (SLP) graduates for working with TGNC clients. A survey was developed to include both multiple choice and open-ended questions. Topics included graduate-level training on working with TGNC individuals, perceived preparedness to work with this client population, educational resources sought by respondents, and suggested improvements for SLP graduate programs. Thirty recent (since 2016) SLP graduates completed the survey anonymously. Although a majority (83%) of respondents reported that working with TGNC clients was addressed in their graduate education, 66% of respondents felt that instruction time spent on this topic was insufficient or slightly insufficient. Those who had clinical experiences with TGNC clients, or who learned from the perspectives of the TGNC community (e.g., from a guest speaker or video), reported that their graduate education better prepared them to work with TGNC clients. One of the most common recommendations to improve graduate education was to invite TGNC speakers to share their experiences. The majority of respondents identified a need for improvement of gender diversity education in SLP graduate programs. Further research is needed to determine the efficacy of different curricula in increasing the knowledge and skills of SLP graduates specific to TGNC clients to ensure clinical competency and equitable care

Gender Diversity Cultural Responsiveness Education in Speech-Language Pathology Graduate Programs: A Pilot Survey

Purpose: Gender-affirming voice therapy aims to align a person’s voice and communication with their gender identity. Historically, transgender and gender-nonconforming (TGNC) individuals have been marginalized and continue to face significant healthcare disparities. The goal of this research was to examine the self-perceived preparedness of recent speech-language pathology (SLP) graduates for working with TGNC clients. A survey was developed to include both multiple choice and open-ended questions. Topics included graduate-level training on working with TGNC individuals, perceived preparedness to work with this client population, educational resources sought by respondents, and suggested improvements for SLP graduate programs. Thirty recent (since 2016) SLP graduates completed the survey anonymously. Although a majority (83%) of respondents reported that working with TGNC clients was addressed in their graduate education, 66% of respondents felt that instruction time spent on this topic was insufficient or slightly insufficient. Those who had clinical experiences with TGNC clients, or who learned from the perspectives of the TGNC community (e.g., from a guest speaker or video), reported that their graduate education better prepared them to work with TGNC clients. One of the most common recommendations to improve graduate education was to invite TGNC speakers to share their experiences. The majority of respondents identified a need for improvement of gender diversity education in SLP graduate programs. Further research is needed to determine the efficacy of different curricula in increasing the knowledge and skills of SLP graduates specific to TGNC clients to ensure clinical competency and equitable care

The Effect of Genetic Taste Status on Swallowing: A Literature Review

Purpose Swallowing and taste share innervation pathways and are crucial to nutritive intake. Individuals vary in their perception of taste due to factors such as genetics; however, it is unclear to what extent genetic taste status influences swallowing physiology and function. The purpose of this review article is to provide background on genetic taste status, review the evidence on the association between genetic taste status and swallowing, and discuss research and clinical implications. Method A comprehensive literature review was conducted using search terms related to swallowing and genetic taste status. Studies were included if they investigated the main effect of genetic taste status on swallowing or the interaction of genetic taste status with other variables. Studies were grouped by participant population (healthy participants or persons with a swallowing disorder), swallowing-related outcome measure, and method of genetic taste status measurement. Results The results were mixed, with five of 10 reviewed studies reporting a statistically significant main or interaction effect on swallowing. Most studies included healthy participants, with only one study investigating participants with dysphagia. Additionally, swallowing-related outcome measures and methods of determining genetic taste status varied greatly between studies conducted on separate cohorts. Conclusion Few studies have incorporated genetic taste status as a variable in swallowing research, and results are mixed. Future research on sensation and swallowing should consider the potential effect of genetic taste status and follow standardized procedures for its determination. Despite the limited evidence, clinicians may consider how individual differences in perception shape swallowing outcomes

Flexibility for Intensity Dosing in Lingual Resistance Exercises: A Large Randomized Clinical Trial in Typically Aging Adults as Proof of Principle

Objective: The objective of this study was to determine the effect of intensity dosing during tongue exercise on tongue pressure generation, adherence, and perceived effort. Design: This was a five-site, prospective, randomized clinical trial. Outcome measures were obtained across multiple baselines, biweekly during exercise, and 4-weeks post-intervention. Setting: The general community at each study site. Participants: Typically aging adults between 55–82 years of age with no history of neurological or swallowing disorders. Eighty-four volunteers completed the study. Interventions: Participants were randomly assigned to one of four exercise groups: (a) maximum intensity/no biofeedback, (b) progressive intensity/no bio- feedback, (c) maximum intensity/biofeedback, and (d) progressive intensity/ biofeedback. Half of the participants completed a maintenance exercise program. Outcome Measures: Maximum isometric pressure (MIP), regular effort saliva swallow pressure, adherence, and the Borg Rating of Perceived Exertion Scale. Results: All exercise protocols were efficacious for gains in MIP (large effect sizes; Cohen’s d). Group 3 made gains in regular effort saliva swallow pressure (medium effect size). There was a significant change in perceived exertion for regular effort saliva swallow pressure at 8 weeks. Tongue pressure gains were maintained at 1 month, regardless of maintenance group status. Mean adherence across groups was high. Conclusions: All groups improved pressure generation. Intensity dosing differences did not affect strength gains, adherence, or detraining. Regular effort saliva swallow pressure may be most responsive to maximum intensity with biofeedback. The findings suggest flexibility in approach to tongue exercise protocols. Tongue muscles may differ from limb muscles in terms of dose response and neuroplasticity principles

Taste Perception and Water Swallow Screen Results in Old-Old Women

Changes in both swallowing and taste commonly occur in advanced age, though the relationship between the two is unknown. This study examined the association between a water swallow screen test and taste identification and intensity rating. Participants included 47 community-dwelling women aged 85⁻94 years. Participants completed three trials of a water swallow screen and were observed for signs of aspiration, which, if present, indicated failure. Four pure taste stimuli at low and high concentrations and water were presented, and participants selected one of five taste labels and rated their intensity on the generalized Labeled Magnitude Scale. Ratios of intensity ratings were computed for each taste stimulus to compare the perception of low and high concentrations. The association between water swallow screen failure, correct taste identification, and taste intensity ratio was evaluated with logistic regression modeling, with mediating factors of frailty and number of comorbidities. Failure of three water swallow screen trials was associated with a higher taste intensity ratio for caffeine (bitter) and a lower taste intensity ratio for sucrose (sweet). Correct identification of taste, frailty, and number of comorbidities were not associated with failure of any number of water swallow screen trials. Intensity ratings of certain tastes may be associated with swallowing in old-old women. Heightened vigilance in this population may be necessary to prevent complications related to dietary intake