Cranial nerves

NEUROANATOMY

1. CRANIAL NERVES PRESENTED BY : DR CHITRANSHA

2. INTRODUCTION Olfactory nerve Optic nerve Oculomotor nerve Trochlear nerve Trigeminal nerve Abducens nerve Facial nerve Vestibulocochlear nerve Glossopharangial nerve Vagus nerve Accessory nerve Hypoglossal nerve There are 12 pairs of cranial nerves in our body. These are called as cranial nerve because the originated directly from the brain or inside the cranium. There names are:

3. Origin of the Cranial Nerves The olfactory nerve (CN I) and optic nerve (CN II) originate from the  cerebrum ( forebrain). Cranial nerves III – XII arise from the  brain stem. 1, 2 - Forebrain 3,4 – Midbrain 5,6,7,8 – Pons 9,10,11,12 – Medulla oblogata All cranial nerves arise from ventral surface except 4 th ( trochlear nerve) which arises dorsaally .

4. ORIGIN 1, 2 - Forebrain 3,4 – Midbrain 5,6,7,8 – Pons 9,10,11,12 – Medulla oblogata

5.   S- 1,2,8 M- 3,4,6,11,12 MIXED-5,7,9,10,

6. Functional Component of Cranial Nerves

7. Motor (efferent) Components: General somatic efferent (GSE) – skeletal muscles which develop from somites . Special visceral efferent (SVE) – muscles derived from pharyngeal arches. General visceral efferent (GVE) – glands, smooth muscles of gut & vessels. Sensory (afferent) Components: General somatic afferent (GSA) – general sensation from skin. (pain, touch, temperature, vibration) General visceral afferent (GVA) – general sensation from viscera. Special visceral afferent (SVA) – special sensations of taste from tongue. Special somatic afferent (SSA) – special sensations of sight, sound, balance

8. OLFACTORY NERVE Olfactory tract

9. OPTIC NERVE