XII Hypoglossal Flashcards
Neurons of hypoglossal nerve XII
Somatic efferent
Terminal sulcus
Point that separates the anterior 2/3 from posterior 1/3 of tongue
Foramen caecum
Point in tongue where the thyroid gland originates and invaginates
Lingual septum
Middle of tongue where the two bilateral origins of the tongue fuse together
Muscles that join at the lingual septum
Genioglossus muscle
Extrinsic muscles involved in degluition
Genioglossus
Palatoglossus
Styloglossus
Hyoglossus
Palatoglossus function
Close oropharynx space when it contracts
Hyoglossus function
Depress the tongue when it contracts
Palatoglossal arch function
Elevate tongue when it contracts
Intrinsic muscles of the tongue
Superior longitudinal
Vertical
Transverse
Inferior longitudinal
Function of intrinsic muscles of the tongue
Important for speech
Geniohyoid muscle origin and function
Not part of the tongue
It is below the intrinsic muscles of the tongue
Function - elevate the hyoid bone
Relationship of hypoglossal XII nerve with both internal and external carotid arteries, stylohyoid muscle and hyoglossus muscle
Superficial to both carotid arteries
Deep to stylohyoid muscle
Superficial to hyoglossus muscle
Hypoglossal nerve XII innervated what intrinsic muscles of the tongue
Hyoglossus
Styloglossus
Genioglossus
Intrinsic muscles
Which nerve is not innervated by hypoglossal nerve XII
Palatoglossus muscle
Innervation of palatoglossus nerve
Pharyngeal branch of vagus nerve X
C1 path
Travels with glossopharyngeal XII fibers
C1 innervates….
Geniohyoid
Thyrohyoid
Internal carotid artery branches
None in the neck
External carotid artery branches in neck
Superior thyroid artery
Lingual artery
Relationship between lingual artery with hypoglossal nerve XII and hyoglossus muscles
Deep to hypoglossal nerve XII
Deep to hyoglossus muscle
XII hypoglossal nerve is superficial to both carotid arteries and to hyoglossus muscle
Somatic afferent definition
Sensing of touch, temperature, pain
Visceral afferent definition
Activate smooth muscle in viscera
SOMATIC AFFERENT innervation of tongue
Anterior 2/3 through lingual nerve (V, trigeminal nerve termination)
Posterior 1/3 through glossopharyngeal nerve (IX)
VISCERAL AFFERENT innervation of tongue
Anterior 2/3 through chorda tympani (VII)
Posterior 1/3 through glossopharyngeal nerve (IX)
Taste of tongue
Anterior 2/3 through chorda tympani VII
Posterior 1/3 through IX glossopharyngeal and X vagus nerve
