Chemical Sensing Regulates Mastication/Swallowing.

Area of Science:

• Neuroscience
• Physiology
• Sensory Science

Background:

• Mastication and swallowing are complex motor functions crucial for digestion.
• These processes involve coordinated muscle activity controlled by the brainstem.
• While somatic sensory input is known to modulate these movements, the role of chemical senses is less understood.

Purpose of the Study:

• To review the effects of chemical sensory inputs on masticatory movements and swallowing initiation.
• To summarize chemical sensory inputs during mastication and swallowing and their mechanisms.
• To discuss the neural mechanisms underlying the effect of taste on swallow initiation.

Main Methods:

• Literature review focusing on chemical senses in mastication and swallowing.
• Summary of receptive mechanisms for chemical stimuli in the oropharynx.
• Introduction of experimental findings on monosodium L-glutamate (MSG) effects on swallow initiation.

Main Results:

• Chemical sensory inputs, including taste and olfaction, play a role in modulating chewing and swallowing.
• The application of umami taste (MSG) to the oropharynx influences the initiation of involuntary swallowing.
• Neural pathways mediating these chemical sensory effects are being investigated.

Conclusions:

• Chemical sensory information is integral to the regulation of masticatory and swallowing functions.
• Understanding these pathways can provide insights into feeding behavior and related disorders.
• Further research is needed to fully elucidate the neural basis of chemical sensory modulation of digestion.