1. Human Physiology The Central Nervous System ▪Thing to be covered ▸ Anatomy of the CNS ▸ The Spinal Cord ▸ The Brain

2. Human Physiology The Central Nervous System ▪Anatomy of the CNS ▸ The Skull or Cranium (for brain) ▸ The Vetebral Column (for spinal cord) ▸ Meninges –Dura mater (outermost layer) –Arachnoid membrane ( middle layer) –Pia mater (innermost layer)

3. Human Physiology The Central Nervous System ▪Cerebrospinal Fluid (CSF) ▸ Cranial vault - 1.4L; cells - 1.0L; blood - 0.1- 0.15L; CSF - 0.2-0.3L ▸ Colorless, salty solution ▸ Continuously secreted from specialized cells (ependymal cells) in the choroid plexus in ventricles ▸ Ependyma actively transport Na + and solutes into ventricles ▸ Functions: Physical and chemical protection ▸ Contains little protein and lower K +, Ca ++, HCO 3 -, and glucose

4. Human Physiology The Central Nervous System ▪Path of CerebroSpinal Fluid

5. Human Physiology The Central Nervous System ▪Three-dimensional view of the ventricles of the Brain

6. Human Physiology The Central Nervous System ▪The Blood-Brain Barrier (BBB) ▸ Function - protection ▸ Brain capillaries much less permeable than others ▸ Protects the brain from blood composition fluctuations ▸ Can transport nutrients into the ISF ▸ Exceptions - posterior pituitary and vomiting center

7. Human Physiology The Central Nervous System ▪Divisions of the CNS ▸ Gray matter ▸ Nuclei ▸ White matter ▸ Tracts - ascending and descending ▸ Spinal cord –Dorsal root (afferent, sensory) –Ventral root (efferent, motor) –Dorsal horns –Ventral horns –Dorsal root ganglion

8. Human Physiology The Central Nervous System

9. Human Physiology The Central Nervous System ▪Organization of the grey matter of the spinal cord Major ascending and descending pathways of the spinal cord

10. Human Physiology The Central Nervous System ▪The Brain ▸ Cerebrum ▸ Brain stem ▸ Cerebellum ▸ Forebrain - cerebrum and diencephalon ▸ Brain stem - midbrain, pons, medulla

11. Human Physiology The Central Nervous System ▪The Brain Stem ▸ Contains the third and fourth ventricles ▸ 9 cranial nerves emerge (know tables 9-1 & 2 ) ▸ Medulla oblongata contains vital centers ▸ Pyramids ▸ Midbrain or mesencephalon controls eye and ear functions ▸ Reticular formation - arousal and sleep

12. Human Physiology The Central Nervous System ▪The Cranial Nerves (Know Table 9-1) ▸ I Olfactory ▸ II Optic ▸ III Oculomotor ▸ IV Trochlear ▸ V Trigeminal ▸ VI Abducens ▸ VII Facial ▸ VIII Vestibulocochlear ▸ IX Glossopharyngeal ▸ X Vagus ▸ XI Accessory ▸ XII Hypoglossal

13. Human Physiology The Central Nervous System ▪The Cerebellum ▸ Process sensory information ▸ Coordinates muscle activity ▸ Involves cordinating balance and equilibrium ▪The Diencephalon ▸ Composed of thalamus and the hypothalamus ▸ Also contains the pineal gland ▸ Thalamus has several nuclei and is described as a relay station for signals on their way to the cerebral cortex ▸ The hypothalamus contains centers for behaviorial drives and homeostasis (See Table 9-2 for more info) ▸ It controls both endocrine and autonomic functions ▸ Receives information from various sources

14. Human Physiology The Central Nervous System ▪The Cerebrum: Lobes and Fissures of the Cerebral Hemispheres: Lateral Left

15. Human Physiology The Central Nervous System ▪The Cerebrum: Lobes and Fissures of the Cerebral Hemispheres: Medial surface Lobes: 1.Frontal 2.Parietal 3.Occipital 4.Temporal 5.Limbic

16. Human Physiology The Central Nervous System ▪Major Regions of the Cerebral Hemipheres

17. Human Physiology The Central Nervous System ▪Functional Area of the Cerebrum

18. Human Physiology The Central Nervous System ▪Motor and Sensory Areas of the Cerebrum

19. Human Physiology The Central Nervous System