Oral behavior from food intake until terminal swallow

Area of Science:

• Oral motor function
• Swallowing physiology
• Food processing

Background:

• Understanding the complex biomechanics of mastication and swallowing is essential for diagnosing and treating oropharyngeal dysphagia.
• Previous research has often focused on controlled or
• command
• swallows, limiting insights into natural eating behaviors.

Purpose of the Study:

• To investigate the oral behaviors during mastication and swallowing under natural, free-eating conditions.
• To elucidate the roles of tongue manipulation, intra-oral food compression, and bolus characteristics in the swallowing process.

Main Methods:

• Videofluorography was used to record oral movements in five subjects during free eating of natural food.
• Measurements included mandibular and tongue movement, gape size, swallowing sequences, and bolus size and movement.

Main Results:

• Tongue manipulation was vital for introducing food, compressing it against the palate, and transporting it to the teeth.
• Intra-oral compression aided in recognizing food texture, and stage I transport was linked to this recognition.
• Most food was swallowed in the first swallow, with residual food forming a final bolus.

Conclusions:

• Humans typically require at least two swallows per bite during free eating.
• Tongue manipulation is critical for evaluating bite volume and food texture.
• The duration of the oral swallowing stage may be influenced by bolus volume, potentially being longer for smaller volumes.