Central Nervous System Week 11 Central Nervous System The Brain Human Brain Brain Sheep

OBJECTIVES Identify the components of the human brain using models and diagrams Identify the cranial nerves Identify the structures of the sheep brain

Objective 1: Anatomy of the human brain and cranial nerves Cerebrum (gold area) Diencephalon (Violet area) Cerebellum (pink area) Brain stem (green area)

Cerebrum

Structures of the Cerebrum Cerebral Hemispheres Fissure Left Hemisphere Right Hemisphere Gyrus Sulcus Frontal cut Ventricles Gray Matter – Cerebral cortex & Basal nuclei White Matter – Myelinated fiber tracts (axons)

Pyramidal Cells of Cerebral Cortex Histology - Recap Recap: Pyramidal Cells of Cerebral Cortex

Structures of the Cerebrum Human Brain, Lateral View Parieto-occipital Sulcus Central sulcus Gyrus Parietal lobe Occipital lobe Frontal lobe Temporal lobe Transverse Fissure Lateral sulcus

Structures of the Cerebrum Human Brain, Superior View Postcentral gyrus Precentral gyrus Central sulcus Longitudinal fissure Frontal pole Occipital pole

Midsagittal Section of Human Brain Corpus Callosum Frontal lobe Parietal lobe Fornix Septum pellucidum Occipital lobe

Internal Structures of the Cerebrum Frontal Section Longitudinal fissure Corpus callosum Septum pellucidum Lateral Ventricles Fornix

Functional areas of the Cerebral Cortex

Functional areas of the cerebrum Cerebral (Basal) Nuclei Initiate, regulate, monitor intensity of & stop movements Maybe help in regulating attention and in cognition Coordination

Diencephalon

Functions of the Diencephalon Endocrine System Relay Stations Thalamus

Structures of & related to the Diencephalon Midsagittal Section Corpus callosum Fornix Thalamus Pineal body/ gland Intermediate mass Hypothalamus Mammillary body

Thalamus Hypothalamus Infundibulum Pituitary gland Sella Turcica

Brainstem

Midbrain: Corpora quadrigemina Superior colliculi Inferior colliculi Cerebral peduncle Pons Medulla oblongata Spinal cord

Brainstem Posterior Pineal body/ gland Corpora quadrigemina Superior colliculus Corpora quadrigemina Inferior colliculus

Structures of the Brainstem Inferior View Optic chiasma Infundibulum Mammilary Bodies Midbrain (Cerebral peduncle) Pons Medulla oblongata Spinal cord

Cerebellum “Little Brain”

Cerebellum Histology - Recap Purkinje Cells

Structures of the Cerebellum Midsagittal Section Cerebellar Peduncles Fourth ventricle Arbor Vitae

Ventricles & Meninges

Meninges of the Brain

Meninges of the Brain A mnemonic PAD from deep to superficial the layers of the meninges are pia, arachnoid, dura (they pad the brain)

The spaces within the brain through which cerebrospinal fluid flows Ventricles of the Brain The spaces within the brain through which cerebrospinal fluid flows

Die-cast model Cerebrospinal fluid is continually produced by the choroid plexus found in the ventricles

Cerebral Aqueduct Third Ventricle Fourth Ventricle

Coronal Section of Brain Ventricles Coronal Section of Brain Corpus callosum Lateral ventricles Dien-ceph-alon Dien-ceph-alon Third ventricle

Cerebrospinal Fluid Circulation Superior sagittal sinus Arachnoid villus Choriod plexus Subarachnoid space Lateral ventricles Vein ? (?) ventricle ? (?) ventricle

Cranial Nerves

12 Pairs of Cranial Nerves Filaments of Olfactory nerve (I) Olfactory bulb Olfactory tract Optic nerve (II) Optic chiasma Oculomotor nerve (III) Optic tract Trochlear nerve (IV) Abducens nerve (VI) Trigeminal nerve (V) Facial nerve (VII) Vestibulocochlear nerve (VIII) Glossopharyngeal nerve (IX) Vagus nerve (X) Hypoglossal nerve (XII) Accessory nerve (XI) On Occasion Our Trusty Truck Acts Funny - Very Good Vehicle AnyHow Oh, Oh, Oh - To Touch And Feel Very Good Velvet - AH!

The Real Thing Nerve (VI) Olfactory Bulb (I) Optic Nerve (II) Oculomotor Nerve (III) Trigeminal Nerve (V) Trochlear Nerve (IV) Abducens Nerve (VI) Facial Nerve (VII) Glosso- Pharyngeal (IX) Vestibulo- cochlear Nerve (VIII) Vagus (X) Hypoglossal Nerve (XII) Accessory Nerves (XI)

FUNCTIONS

End Objective 1

Objective 2: Sheep Brain Dissection

Identify the external structures 1 Identify the external structures Inferior Sheep brain structures are the same as the human brain, only slightly different sizes

Same structures as human brain, only slightly different size 2 Remove Dura mater (w/ pituitary gland) Identify the external structures Superior Same structures as human brain, only slightly different size 40

Identify the external structures Inferior

Pull back the cerebellum to reveal Corpora Quadrigemina & Pineal Gland 3 Pull back the cerebellum to reveal Corpora Quadrigemina & Pineal Gland

Make a midsagittal cut through the brain 4 Make a midsagittal cut through the brain                                                                                  

5                                                                                                  Brainstem Diencephalon

Identify the internal structures Midsagittal

Identify the internal structures Midsagittal Lateral Ventricle Fourth Ventricle Cerebral Aqueduct Third Ventricle

You may begin!