Genioglossus

Genioglossus is a significant muscle in the human oral cavity, playing a crucial role in various functions including speech, mastication (chewing), and swallowing. It is one of the extrinsic muscles of the tongue, meaning it originates outside the tongue but has an effect on its position and shape.

Anatomy

The genioglossus muscle originates from the mandible, specifically the superior genial tubercles on the inner surface of the mandibular symphysis. From this point, the muscle fibers extend in a fan-like distribution to insert throughout the bottom of the tongue and the hyoid bone. This unique insertion allows the genioglossus to perform multiple actions on the tongue.

Function

The primary function of the genioglossus is to protrude the tongue out of the mouth. However, it also contributes to the depression of the tongue, making it essential for creating a clear pathway during respiration and aiding in the initial phase of swallowing. Additionally, the genioglossus helps in speech articulation by altering the shape and position of the tongue.

Clinical Significance

The genioglossus muscle is of particular interest in the study of sleep apnea, a condition characterized by repeated episodes of upper airway obstruction during sleep. Weakness or dysfunction of the genioglossus can lead to the collapse of the airway, contributing to the pathophysiology of obstructive sleep apnea. Treatments aimed at strengthening or stimulating the genioglossus have been explored as potential therapeutic options.

Innervation

The genioglossus is innervated by the hypoglossal nerve (Cranial Nerve XII), which supplies motor innervation to all the extrinsic and intrinsic muscles of the tongue, except for the palatoglossus.

See Also

• Extrinsic muscles of the tongue
• Intrinsic muscles of the tongue
• Mandible
• Hyoid bone
• Sleep apnea