The document discusses the anatomy and functions of the glossopharyngeal and vagus nerves. It describes the three components and nuclei of the glossopharyngeal nerve, including its motor, parasympathetic, and sensory functions. It then discusses the vagus nerve, noting its motor and sensory nuclei and parasympathetic roles in involuntary muscles. Finally, it summarizes the relationship between the two nerves, where the glossopharyngeal carries sensory information from the carotid body and sinus to the vagus nerve, which can then affect the heart rate and blood pressure.

2. Amna liaqat
Roll#51
BDS3rd yr

3. It is the Ninth cranial nerve
It has three components:
1. Motor
2. Secretomotor parasympathetic
3. sensory
 It has three nuclei:
1. Main motor
2. Parasympathetic
3. Sensory

5. 1.Main motor nucleus
Lies deep in medulla oblongata.
Receives afferent fibres from both
cerebral hemispheres.
Give efferent fibres to Stylopharyngeus
muscle.

6. 2.Parasympathetic nucleus
It give preganglionic efferent fibres to
1. Tympanic branch of 9th nerve
2. Tympanic plexus
3. Lesser petrosal nerve
 The postganglionic fibres pass to
Parotid salivary gland.

7. 3.Sensory nucleus of
the tractus solitarius
General sensation & taste sensation
to posterior 3rd of tongue & pharynx.
Afferent sensory fibres from the
Carotid body & carotid sinus.

9. Emerges from medulla oblongata
b/w olives & inferior cerebellar
Peduncle.
Passes laterally in post. Cranial fossa
Leave the skull by juglar foramen
Than it passes to the lateral side of
neck & gives branches.

12. 1.Tympanic branch
Sensory supply to middle ear
2.Lesser petrosal nerve
Secretomotor fibres for Parotid salivary
Gland
3.Phyrangeal branches
Form pharyngeal plexus with vagal &
Sympathetic fibres

13. 4.Muscular branches
Supply to stylopharyngeus muscle
5.Tonsillar branches
Supply tonsills & soft palate
6.Lingual branches
Supply general & taste sensations to
Post. third of tongue
7.Carotid branch
Descends on internal carotid artery
& supplies the carotid body & carotid
Sinus.

15. It is the 10th cranial nerve
It arises from the same area of brain
as of the Glossophyrangeal nerve
It also exit through juglar foramen
It has two components
1. Motor
2. sensory

17. Vagus nerve has three nuclei:
1.Main motor nucleus
Efferent fibres supply constrictor
muscle of pharynx & intrinsic muscle
of larynx.
2.Parasympathetic dorsal motor nucleus
Receives afferent fibres from
1.Hypothalmus
2.Glossopharyngeal nerve
(from Carotid sinus & Carotid body)

18. It sends efferent fibres to
involuntary muscles of bronchi,
Heart,stomach,esophagus,small
& large intestine.
3.Sensory nucleus
Taste sensations to epiglottis.

25. The glossopharyngeal & vagus nerves
are related to each other through:
The carotid branch of 9th nerve
carries the sensation of any
change in blood pressure or in
chemical constituents of blood from
Carotid body & carotid sinus through
afferent fibres.

26. These afferent fibres reach
parasympathetic dorsal motor
nucleus of Vagus nerve.
Vagus nerve inturn sends efferent
Fibres to the involuntary muscles of
Heart,which in turn results in either of
the following accordingly:
Bradycardia
Hypotension
Syncope
asystole

27. All of these show the predominant
Parasympathetic effect of Vagus nerve
on heart.

30. CLINICAL NEUROANATOMY by
Richard S.Snell
B D Chayrasia’s HUMAN ANATOMY
Head & Neck