Central nervous system introduction

Anatomy

1. NERVOUS SYSTEM Dr. Shabana Ali IIMC

2. Divisipn Meninges

3. INTRODUCTION Nervous system is divided Anatomically into: 1. Central Nervous System. 2. Peripheral Nervous System. Functionally it is divided into: 1. Somatic Nervous System . 2. Autonomic Nervous System .

4. 1.Central nervous system 1.Brain and 2.spinal cord Parts of brain Forebrain or prosencephalon Midbrain or mesencephalon Hindbrain or rhombencephalon

5. INTRODUCTION Parts of hindbrain Pons Medulla oblongata Cerebellum

6. 2.spinal cord Starts at foramen magnum and ends at L2 level.

7. 2.Peripheral nervous system Twelve pairs of cranial nerves Thirty one pairs of spinal nerves Cervical – 8 Thoracic – 12 Lumbar – 5 Sacral – 5 Coccygeal – 1

8. Composition of a spinal nerve Sensory fibres Motor fibres Autonomic fibres

9. Peripheral nervous system Brain stem Cranial nerves Spinal cord

10. Coverings of the brain(Dap ) Dura mater---outermost Arachnoid mater--- middle S2 LEVEL Pia mater---innermost---- coccycx Also cover the spinal cord after passing through foramen magnum

11. DURAL FOLDS 1.Falx cerebri 2.Tentorium cerebelli 3.Falx cerebelli

12. DURAL FOLDS Falx cerebri

13. VENOUS SINUSES OF BRAIN

14. DURAL VENOUS SINUSES

15. LOBES OF THE BRAIN

16. CEREBRAL LOBES

17. Central sulcus parietoocipital sulcus Lateral sulcus

18. Cerebral lobes

19. AREAS IN THE CORTEX

20. Arteries of the brain

21. BLOOD SUPPLY OF CEREBRUM Ant cerebral Middle cerebral Post cerebral

22. Spinal cord Foramen magnum to lower border of L1 or upper border ofL2

23. COVERINGS OF THE SPINAL CORD DURA MATER ARACHNOID MATER PIA MATER

24. SECTION THROUGH VERTEBRAL COLUMN Vertebral body pedicle spine lamina Grey mater White mater

25. Blood supply Anterior and posterior spinal artery

26. Components of spinal nerve Ventral ramus and dorsal ramus Spinal nerve Divides into anterior and posterior rami Anterior --- -- body nerve plexus Posterior rami — sensory innervation to a skin segment known as a dermatome

27. Ventral Roots The ventral (motor) roots consist of efferent fibers that convey output from the spinal cord . There are two components: ( 1) innervate voluntary striated muscles , ( 2) influences to involuntary smooth muscles,cardiac muscle, and glands

28. Voluntary muscles and spinal nerve root Ventral spinal root Muscles innervated C5–6 Biceps brachii (flexes elbow) C6–8 Triceps brachii (extends elbow) T1–8 Thoracic musculature T6–12 Abdominal musculature L2–4 Quadriceps femoris (knee jerk, patellar tendon reflex) L5–S1–2 Gastrocnemius (ankle jerk, Achilles tendon reflex

29. Innervation by posterior ramus Dorsal spinal root Body region innervated C2 Occiput C4 Neck and upper shoulder T1 Upper thorax and inner side of arm T4 Nipple zone T10 Umbilical girdle zone L1 Inguinal region L4 Great toe, lateral thigh, and medial leg S3 Medial thigh S5 Perianal region

30. SECTION THROUGH SPINAL CORD

31. Autonomic nervous system Two parts Sympathetic Parasympathetic Functions of autonomic N S Involuntary Controls activities of heart, smooth muscles of GIT, blood vessels & glands

32. Neuron Smallest functional unit is neuron It consists of cell body and cell processes

33. Types of neuron Unipolar Bipolar Pseudo uni polar Multipolar

34. BONES AT THE BASE OF THE BRAIN