EXERCISE 19: BRAIN AND CRANIAL NERVES http://www.vision.caltech.edu/feifeili/101_ObjectCategories/brain/image_0026.jpg

FOREBRAIN MIDBRAIN HINDBRAIN

CEREBRUM Transverse Fissure

ON PARIETAL LOBE Primary somatosensory area ON FRONTAL LOBE Primary motor area

Cortex (superficial) is gray matter White matter is deeper

DIENCEPHALON= thalamus + hypothalamus

Sensory Nerve Attachments Optic nerves: to eyes Optic chiasm: cross Optic tracts: to brain

Endocrine Attachments Pineal Gland

MIDBRAIN CORPORA QUADRIGEMINA

HINDBRAIN

HINDBRAIN--cerebellum

MENINGES Same setup as spinal cord— Dura mater most superficial, Arachnoid, Pia mater closest to brain

CHOROID PLEXUSES Specialized capillaries in ventricles Produce CSF—Circulates from here to central canal (s. cord) & around outside of brain/cord too

CRANIAL NERVES 12 pairs Connect to brain: CN I cerebrum CN II thalamus CN III-XII brain stem O O O T T A F V G V A H S S M M B M B S B B M M Nerve names: Nerve functions:

CN I: OLFACTORY SENSORY Smell From olfactory epithelium Olfactory nerve-bulb-tract (Cribriform foramina of ethmoid) 14-21

CN II: OPTIC SENSORY From retina Optic nerve-chiasm-tract (Optic canal-sphenoid) 14-22

CN III: OCULOMOTOR Mostly MOTOR To eye muscles (superior orbital fissures-sphenoid) 14-22

CN IV: TROCHLEAR Mostly MOTOR To superior oblique eye muscles (superior orbital fissures-sphenoid) 14-22

CN V: TRIGEMINAL Mixed (sensory and motor) Ophthalmic Branch Sensory-orbital, upper face structures Maxillary Branch Sensory-lower face structures Mandibular Branch Mixed-mouth

14-24

CN VI: ABDUCENS Mostly motor To lateral rectus eye muscles (superior orbital fissure) 14-23

CN VII: FACIAL Mixed To parts of face Expressions, tear/salivary glands 14-25

CN VIII: VESTIBULOCOCHLEAR Sensory, from inner ear Vestibular branch Balance, equilibrium Cochlear branch Hearing 14-26

CN IX: GLOSSOPHARYNGEAL Mixed to head and neck Sensory: posterior tongue Motor: pharyngeal muscles (swallowing), salivary gland 14-27

CN X: VAGUS Mixed to visceral organs, larynx, pharynx Sensory: ear, diaphragm, organs Motor: pharynx, digestive, respiratory, cardiovascular systems 14-28

CN XI: ACCESSORY Join at foramen magnum Mostly motor To muscles of neck, upper back Cranial root Fibers originate in medulla Spinal root Some motor fibers originate in spinal cord Join at foramen magnum 14-29

CN XII: HYPOGLOSSAL Mostly motor To tongue muscles 14-29

CRANIAL NERVES

Sheep Brain Dissections http://www.gwc.maricopa.edu/class/bio201/brain/brshpx.htm http://www.biology.ualberta.ca/courses.hp/zoo.225/lab8.html http://darwin.baruch.cuny.edu/gelfond/Bio1005/neural.htm http://a-s.clayton.edu/biology/biol1151L/lab10/lab_10.htm