Brainstem and Cranial Nerves – 2 Human Neurobiology ANHB 2217 Avinash Bharadwaj Semester 1, 2006 Week 2
Medulla Oblongata Central canal Cuneate and gracile tubercles G Cu Inf. cerebellar peduncle Pyramid and Olive P O ICP IV Ventricle
Pons Basilar part, tegmentum, MCP Basilar Tegmentum MCP
Midbrain SC Tegmentum SN Crus Tectum
Nerve III and Midbrain Oculomotor “Extrinsic” Muscles of the eyeball : GSE Nucleus close to the midline Constrictor of the pupil (smooth muscle) GVE : Edinger-Westphal nucleus SC III SN RN C-Sp CP ST
Nerve IV Trochlear nerve A muscle of the eyeball winds around a trochlea (pulley) GSE Exceptional course IC
Nerve VI - Abducens Nerve to the “abductor” of the eyeball GSE Nucleus close to the midline VI Pontine nuclei MCP
Nerve V : Trigeminal Mixed nerve Sensory : general (GSA) Nucleus in all three parts of the brainstem Motor : Muscles of mastication ++ (1 st branchial arch muscles) -- Special Visceral SVE Nucleus in pons
Nerve V : Trigeminal Sensory Mesencephalic Proprioceptive An unusual nucleus Pontine (Chief) Discriminative touch Spinal Tract and nucleus (MO) Touch, pain, temperature Motor Pons
Nerve VII - Facial Motor : 2 nd branchial arch Facial muscles ++ SVE GVE glands Taste : SVA Also general sensory… VII MCP
Pons Relationships : VI, VII and V Rostral level : Motor nucleus of V in line with VII VI VII V Pontine nuclei Pontine nuclei : Cerebrum-cerebellum connection (Motor system) MCP
Nerve VIII : Vestibulocochlear Cochlear nuclei Auditory Vestibular nuclei Head position and movement Both special sensory : SSA PP ICP
Nerves IX and X IX : Glossopharyngeal General sensory : tongue + pharynx : GSA Taste : SVA Glands : GVE Branchial muscle (pharynx) : SVE PP ICP X : Vagus : Wide area of distribution GVE : Muscle of thoracic and abdominal organs, glands Taste : SVA Branchial muscle…
Nerve XI : Accessory IX, X, XI as a nerve group SVE component of X : Fibres of XI Nucleus ambiguus Spinal root of accessory Trapezius and sternocleidomastoid muscles Developmental origins…?
Nerve XII : Hypoglossal Muscles of the tongue GSE XII XI V XII XI V PP ICP
Medulla Oblongata Recognise landmarks XII nucleus – close to midline XI and V Cuneate and gracile nuclei Inferior olivary nucleus Inferior cerebellar peduncle XII XI V XII XI V PP ICP