“Humans may crave absolute certainty; they may aspire to it; they may pretend ... to have attained it. But the history of science—by far the most successful claim to knowledge accessible to humans—teaches that the most we can hope for is successive improvement in our understanding, learning from our mistakes, an asymptotic approach to the Universe, but with the proviso that absolute certainty will always elude us.
We will always be mired in error. The most each generation can hope for is to reduce the error bars a little, and to add to the body of data to which error bars apply. The error bar is a pervasive, visible self-assessment of the reliability of our knowledge.”
The Demon-Haunted World: Science as a Candle in the Dark, Astronomer and Writer Carl Sagan
Here is a confession: I have a love/hate relationship with Facebook. In particular, I have a love/hate relationship with speech language pathology forums on Facebook. I have learned a great deal and been inspired by many of the posts; I have also seen some pretty disrespectful conversations around a variety of controversial topics.
And so, when my post featuring a giraffe looking like he/she was doing the masako exercise went viral, I watched as once again, an SLP Facebook forum proceeded to build a fence: On one side, people who use the exercise based on graduate level and clinical training, and on the other side, people who had received other information and were adamant that the exercise is either A) a waste of time, B) detrimental to people’s swallow; C) not evidence-based and therefore not usable, or D) all of the above.
This brought up a lot of thoughts about the profession of speech-language pathology: namely, that though we are ethically required to stand strongly behind our therapy practices, the ground that we walk on is woefully inadequate. Our therapy practices are based on extremely limited research in a field that is truly in its infancy. Somehow, we have collectively as a field gotten to a point of black and white mythology in a world of a billion shades of grey.
In 2008, ASHA compiled an international list of members who identified as researchers. The list contained 1,233 people, about 750 of whom conducted research in the field of speech language pathology. 69% of this number held a doctoral degree. Of all of these, 50% of their time was devoted to research and 50% of their time was devoted to teaching. 53% of the respondents reported they were working on a study that involved the treatment of a disorder. 46% reported limited access to appropriate funding streams. 23% reported they were able to produce a randomized controlled clinical study. 43% reported they were able to draw participants from health care settings.
Forgive my gross analysis of this data, and forgive the fact that I’m extrapolating numbers based on the data of the 303 responses they received to their survey, but that means that approximately 274 people with SLP doctoral degrees are spending half their time conducting studies to provide all of the evidence-base for all of the hundreds of interventions that speech language pathologists provide. To take it further, of those 274 researchers, 63 of them produce randomized controlled clinical studies. 118 are actually doing these studies with people in health care settings (not college students or normal adults). Almost half of them don’t have enough funding to adequately complete their studies.
The most popular areas of research interest, out of the 64 areas that were listed, were language disorders (36%), language acquisition (28%), language (24%), normal processes (22%), and literacy (22%). Hearing (20%), aging (19%), neurogenic communication disorders (19%), learning disabilities (18%), and cochlear implants (16%) followed.
Dysphagia was not listed amongst the most popular areas, nor mentioned in the 2008 ASHA Researcher Survey executive summary at all.
Where does this leave us?
All. over. the. map. You name the intervention, it’s up in the air. Neuromuscular electrical stimulation. The blue dye test. FEES vs MBSS. Swallow exercises. Oral motor exercises. I learned one thing in grad school only to un-learn it at internships and then to meet 5 other SLPs with 5 different opinions about what is right and what is wrong.
For the sake of this letter and to illustrate the nature of these conversations, let’s touch on the history and current research on the efficacy of the masako exercise: The masako was introduced by Fujiu and Logemann in 1995, who published their study showing that all 10 of their healthy, normal subjects exhibited an increase in anterior bulge of the post-pharyngeal wall with the exercise as compared to their swallows without the maneuver. They introduced the idea of the masako as both a treatment and evaluation tool, to increase anterior bulge of the post-pharyngeal wall and to test for the compliance of the post-pharyngeal wall in people with dysphagia.
The masako is listed as a dysphagia exercise on ASHA’s list of Oral-Motor Therapy/Exercises. It is featured on the website for the National Foundation of Swallowing Disorders.
In 2015, Langmore and Pisenga attempted to verify the efficacy of the masako research initially published by Fujiu and Logemann, but reported that because it had no control group and the subjects were normal, the results could not be generalized. However, Fujiu and Logemann never intended for this to be a conclusive study, stating: “Although more systematic studies in patient populations are needed before applying the maneuver in treatment, the results of this study suggest the potential for developing new approaches in therapy.”
Initial research into the effects of the masako exercise in participants with surgical tip of tongue resection due to oral cancer documented increased anterior movement of the posterior pharyngeal wall in 7 of 11 participants. Lazarus and colleagues documented the effects of swallowing maneuvers on pharyngeal biomechanics of 3 participants with reduced base of tongue-post pharyngeal wall contact pressures subsequent to treatment for head and neck cancer. During masako swallows, increased base of tongue-post-pharyngeal wall contact pressures were measured with concurrent manometry and videofluoroscopy compared with normal saliva swallows.
Doeltgen et al investigated the immediate effects of the masako on four biomechanical measures of deglutitive pressure generation in healthy individuals. Their study concluded that the masako exercise may produce increased pharyngeal constrictor strength and ultimately increased pharyngeal pressure generation after regular training, though they also noted that increased pharyngeal constrictor strength, however, may have negative implications for hyoid anterior movement.
One study that took a look at the effects of the masako after completing the exercise for several weeks in subjects with dysphagia was by graduate student Jessica Pisegna who wrote a thesis at Boston University and presented at ASHA in 2014, which showed cautious support for the exercise.
In 2016, Byeon studied the effect of the masako and neuromuscular electrical stimulation on the improvement of swallowing function in 47 patients with dysphagia caused by stroke. That research concluded that the masako and neuromuscular electrical stimulation each showed significant effects on the improvement of swallowing function for the patients with dysphagia caused by stroke, but no significant difference was observed between the two treatment methods.
In Carroll et al’s study, half of 18 patients with advanced squamous cell carcinoma of the oropharynx, hypopharynx, and larynx being treated for head and neck squamous cell carcinoma received swallowing exercises during routine post-treatment management. The masako was included in the suite of exercises. Their study concluded that epiglottis inversion was better maintained and the position of the tongue base during swallowing was also significantly closer to the posterior pharyngeal wall for patients receiving pretreatment exercises. Because other swallow exercises were included, it’s unclear to what extent the masako exercise impacted these results.
The efficacy of the masako exercise has been a point of discussion on Facebook SLP forums dozens of times, all with wildly different flavors to the conversation. Sometimes it's glorified, sometimes it's vilified. The word “bully” has been thrown around in reference to clinicians who verbalize disagreement with the exercise, as well as requests for clinicians who do use the exercise to “stop spreading misinformation.”
This post is not meant to be a conversation about the efficacy of the masako exercise. The reality is that almost every intervention in our field has this level of uncertainty and woefully inadequate research base, and so this conversation could devolve into a debate about every single intervention we have at our fingertips.
So let’s make the conversation bigger.
We can all agree that research in our field is vastly inadequate. Our error bars across the realm of interventions are large. This inadequacy is not necessarily because we don’t have enough SLPs doing research (although this is very true). It is simply because the human body, in all of its infinite manifestations, is not a carbon copy from one soul to another. One brain does not act like another. One brain injury located in the same spot across a population of a billion people will manifest itself a billion different ways. Randomized controlled studies are often impossible due to ethical dilemmas (who in the world is going to deny their family member the better treatment option?) Degenerative diseases degenerate at different paces and in different ways for different people. No one, absolutely no one will present with the same baseline, maintain all the same variables, and create results that are reproducible by other researchers studying similar people.
Like most science, the vast majority of research in our field will be baby steps toward conclusive evidence based practice. Very few impairments and related interventions are so black and white that one study can provide all of the answers or another study can debunk all of the ideas.
Here is my hope for all of us and the field of speech-language pathology:
- That we embrace the uncertainty that lies before us, and respect and believe that each clinician will do everything in their power to provide patients with every possibility of improving their impairments and living their life to the fullest.
- That the meaning of evidence-based practice encompasses not only research based published articles, but also clinical expertise and patient values and preferences.
- That the safeguards we have set up throughout the clinical training and certification process at state and national levels ensure highly ethical practice and also leave room for inevitable ambiguity, thoughtful discussion, and respect for the creativity and innovation necessary of each of us in our day-to-day practice.
- That 100 years from now, our understanding of dysphagia, language, and cognitive-linguistic disorders will be adequately funded and researched, that our error bars will shrink, and yet in the midst of growing certainty, that we leave room for the fact that absolute certainty will always elude us.
Megan Berg, MA, CCC-SLP
Other food for thought:
Susan Etlinger on the Ted Radio Hour: How Do We Approach Big Data With A Critical Eye?
The Peer Review Podcast: Episode 5: Crowdfunding science: Is it possible for the collective public to fund our research projects?Decolonization of knowledge, epistemicide, participatory research and higher education: This article raises questions about what the word ‘knowledge’ refers to. Drawn from some 40 years of collaborative work on knowledge democracy, the authors suggest that higher education institutions today are working with a very small part of the extensive and diverse knowledge systems in the world.
SourcesFujiu, M., & Logemann, J. A. (1996). Effect of a Tongue-Holding Maneuver on Posterior Pharyngeal Wall Movement During Deglutition. American Journal of Speech-Language Pathology, 5(1), 23.
Langmore, S. E., & Pisegna, J. M. (2015). Efficacy of exercises to rehabilitate dysphagia: A critique of the literature. International Journal of Speech-Language Pathology, 17(3), 222-229.
Fujiu, M., Logemann, J. A., & Pauloski, B. R. (1995). Increased Postoperative Posterior Pharyngeal Wall Movement in Patients With Anterior Oral Cancer. American Journal of Speech-Language Pathology, 4(2), 24.
Doeltgen, S. H., Witte, U., Gumbley, F., & Huckabee, M. (2009). Evaluation of Manometric Measures During Tongue-Hold Swallows. American Journal of Speech-Language Pathology, 18(1), 65.
Pisegna, Jessica & Langmore, Susan. (2014). The Efficacy of the Masako (Tongue-Hold) Maneuver: A Pilot Study.
Byeon, H. (2016). Effect of the Masako maneuver and neuromuscular electrical stimulation on the improvement of swallowing function in patients with dysphagia caused by stroke. Journal of Physical Therapy Science, 28(7), 2069-2071.
Carroll. W, et al (2008). Pretreatment Swallowing Exercises Improve Swallow Function After Chemoradiation. Laryngoscope, 118:39-43.
American Speech‐Language‐Hearing Association. (2010). 2008 ASHA Researcher Survey: Executive summary. Available from www.asha.org.