Biomechanical and Cortical Control of Tongue Movements During Chewing and Swallowing.
Callum F Ross, J D Laurence-Chasen, Peishu Li and 2 others
PMID 37326668WHAT IT FOUND
Chewing and swallowing require tongue shape changes, oral sensation, and cortical control.
Loss of oral sensation or stroke-related cortical damage can disrupt food handling and swallowing, but no treatment is tested.
Key findings
01Lingual dysfunction is associated with swallowing and speech disorders, including dysphagia, dysarthria, apraxia of speech, and cortical stroke.
02Oral sensory loss mainly disrupts the timing and coordination of tongue and jaw movement during chewing, while average tongue shape changes are relatively preserved but more variable.
03Stroke involving sensorimotor cortex can produce swallowing deficits that differ by side: right-sided stroke is associated with pharyngeal pooling and aspiration, left-sided stroke with oral-phase difficulty and apraxia.
STILL TO COME
How it was doneWhat they foundWhat it means for SLPs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
Most direct kinematic and neural-control data come from animal models, especially macaques, pigs, cats, rats, and rabbits, not from patients. The paper is a review of existing evidence, not a clinical trial, so it does not show that any therapy improves chewing or swallowing. The authors state that human tongue kinematics during early food transport are not well documented and that mechanisms of tongue base retraction are debated. The authors also state that simple measurements of tongue and hyoid movement alone cannot distinguish mechanisms without other evidence such as regional tongue volume and oral volume changes. Many questions about how anatomy, sensation, and cortex interact across species remain unresolved.
Declared interests
Funding was provided by the National Science Foundation, the National Institute of Child Health and Human Development, and the National Institute of Dental and Craniofacial Research. The supplied text does not state author conflicts of interest.
The easy way to misread this
Do not conclude that tongue exercises, sensory stimulation, or cortical stimulation improve swallowing from this paper. It describes mechanisms and animal findings; it does not test a treatment in patients.