Publications by authors named "Nobuaki Saka"

The sternohyoid muscle depresses the hyoid bone, but it is unclear whether the muscle contributes to respiratory and swallowing mechanisms. This study aimed to clarify whether the sternohyoid muscle participates in the respiration and swallowing reflex and how the activity is modulated in two conditions: with airway stenosis and with a fixed sternohyoid muscle length. Electromyographic activity in the sternohyoid, digastric, thyrohyoid, and diaphragm muscles was recorded in anesthetized rats.

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Mastication is controlled by central pattern generator in the brainstem and can be modulated by volition. The aim of this study was to investigate the effect of chewing well on swallowing. Twenty-six healthy participants were instructed to eat 8, 12, and/or 16 g of steamed rice with barium sulphate under the following two conditions: chewing freely task (CF; chewing naturally in their usual manner) and chewing well task (CW; chewing the food with a request to "chew well").

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The external carotid artery (ECA) plays a major role in supplying blood to the head and neck. Although impeded blood flow in the ECA is expected to affect orofacial functions, few studies have shown how blood flow obstruction in the ECA contributes to impairment of these functions, including chewing and swallowing. This study was performed to investigate the effects of ECA ligation (ECAL) on immediate and long-term changes in masticatory and swallowing functions as well as the jaw-opening reflex evoked in the digastric muscle.

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Background: Chewing and licking are primarily activated by central pattern generator (CPG) neuronal circuits in the brainstem and when activated trigger repetitive rhythmic orofacial movements such as chewing, licking and swallowing. These CPGs are reported to modulate orofacial reflex responses in functions such as chewing.

Objective: This study explored the modulation of reflex responses in the anterior and posterior bellies (ant-Dig and post-Dig, respectively) of the digastric muscle evoked by low-intensity trigeminal stimulation in conscious rats.

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Background: Oral hypofunction is defined as the reversible stage preceding oral dysfunction. However, its assessment and management need further examination and consideration.

Objective: The present study aimed to examine the current state of oral hypofunction among outpatients at the university hospital.

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