Human Oral Sensory Systems and Swallowing

Abstract

Numerous oral sensations contribute to the flavor experienced from foods. Texture is sensed throughout the mouth by nerve endings in the oral epithelium. Chemesthetic sensations, including irritation, spiciness, and chemical burn or cooling, are sensed by these same nerves. Tastes are sensed by taste buds, primarily on the tongue, which transduce information through the gustatory nerves. Even after placing food in the mouth, odor is still experienced through retronasal olfaction, the air that passes through the rear of the oral cavity into the nasal passages. All of these sensations combine to give an overall experience of flavor. In individuals with dysphagia, these oral sensory systems can be used to improve swallowing function. Texture is the most common current approach, but the other oral sensations, particularly chemesthesis, may also hold potential for making sensory modified foods for dysphagia management. However, modifying any of these sensory properties also alters the overall food flavor, which can lead to decreased liking of the food.