1. 1 Chapter 2b CNS Gross Anatomy Chris Rorden University of South Carolina Norman J. Arnold School of Public Health Department of Communication Sciences and Disorders University of South Carolina

2. 2 Brain Sub-Divisions Telencephalon – Cortex, Limbic system, basal ganglia, olfactory bulb Diencephalon Thalamus, Hypothalamus Mesencephalon Tegmentum, Red Nucleus, Colliculi Rhombencephalon Pons, Cerebellum, Medulla Spinal Cord

3. 3 Diencephalon Diencephalon = thalamus, hypothalamus, epithalamus, prethalamus or subthalamus and pretectum Thalamus –Oval Mass of Neurons in the Center of the Brain –Relays Sensorimotor Information to the Cortex

4. 4 Thalamus Poor contrast on MRI scans – hard to see.

5. 5 Thalamic Injury T2-weighted MRI Bilateral injury to parts of thalamus

6. 6 Diencephalon Hypothalamus –Body Heat, Water intake, Hormone Production, Emotional Expression, Food Consumption and Reproduction

7. 7 Midbrain, Hindbrain Pons Medulla Oblongata Functions: Automatic Control Systems

8. 8 Ventral Brainstem Mamillary Bodies Medial Sulcus Ventral Median Fissure Pyramidal Tract Pyramidal Decussation –Where signals cross Ventral lateral sulcus

9. 9 Midbrain Dorsal Structures Superior and Inferior Colliculus –The ‘little hills’. –Superior colliculi – help initiate eye movements, integrate visual, auditory and tactile information –Inferior colliculi- audition Aka Corpora Quadrigemina (four seeds) Dorsal View of Brainstem Pineal Body Brachium Superior Colliculus Inferior Colliculus Superior Inferior Trochlear Nerve

10. Colliculi Superior colliculi: eye movement control. Also maps touch and hearing onto vision Inferior colliculi: pathway for auditory processing Sagittal View

11. 11 Internal Structures of the Midbrain Tegmentum Cerebral Aqueduct Red Nucleus Cranial nerve nuclei Reticular Formation Central Gray Area Transverse Section of Rostral Midbrain Tectum Tegmentum Basis Pedunculi

12. 12 Internal structures of the pons Tegmentum –Ascending and Descending Fibers –Medial Lemniscus Basilar Pons –Cortical Descending Tracts –Pontine Nuclei –Pontocerebellar Fibers Transverse Section of Mid Pons Teg- mentum Basilar

13. 13 Medulla Oblongata Connects to Pontine Protrusion Caudal Portion Contains Pyramidal Decussation Where motor tracts cross over for control of contralateral side of the body Tegmentum Pyramid

14. 14 Landmarks of Medulla Ventral –Ventrolateral Sulcus –Pyramidal Tract –Lateral Corticospinal Motor Tract Dorsal –Dorsal Median Sulcus –Dorsolateral Sulcus –Olivary Nucleus

15. 15 Internal Medulla Dorsal Tegmentum Ventral Pyramidal Tract Reticular Formation –Cardiac Center –Vasomotor Center –Respiratory Center

16. 16 Cerebellum Modifies Cortical Activity Distinctive Appearance –Gyri called Folia –Two Hemispheres Three Lobes –Anterior –Posterior –Flocculonodular

17. 17 Cerebellum Posterior lobe Anterior lobe Rostral view –(bird’s eye)

18. 18 Cerebellum Caudal view (from the feet) Posterior lobe Anterior lobe Flocculus

19. 19 Cerebellum Anterior view Nodulus Flocculus

20. 20 Cerebellum Midsagittal slice Flocculus Nodulus