1. Neurophysiology of the central nervous system Dr. Loai Alzghoul Loai.physiology@yahoo.com

2. Organization of the nervous system

4. Levels of the CNS 1)Spinal cord 2)Brain stem and sub cortical 3)Cerebral cortex

5. 3 Major Levels of CNS Function The spinal cord level. –more than just a conduit for signals from periphery of body to brain and vice versa. –cord contains: walking circuits. reflexes circuits.

6. The brain stem and subcortical Contains: –medulla, pons, mesencephalon, hypothalamus, thalamus, cerebellum and basal ganglia. Controls subconscious body activities: –arterial pressure, respiration, equilibrium, feeding reflexes, emotional patterns.

7. The Higher Brain or Cortical Level Higher order functions : language, thoughts and personality Large memory storehouse. Each portion of the nervous system performs specific functions, but it is the cortex that opens the world up for one’s mind.

8. Organization of the Nervous System Sensory Division –tactile, visual, auditory, olfactory. Motor Division –respond to and move about in our environment. Integrative Division –process information, creation of memory.

9. Figure 45-2 Somatosensory Axis of the Nervous System

10. Figure 45-3 Skeletal Motor Nerve Axis of the Nervous System

12. Terminology: Afferent VS Efferent

13. Terminology: 1 st order, 2 nd order and 3 rd order neurons

14. Histology of the NS

15. Neuron Structure

16. Types of neurons

17. Neuroglia

18. Myelination

19. Neuroglia Myelination In PNS = Schwann cell

20. Neuroglia Form the blood- cerebrospinal fluid barrier

21. Neuroglia

22. Phagocytize

23. Neuroglia Astrocytes 1)Support for neurons 2)Form the blood –brain barrier 3)Learning and memory 4)Maintain the prober environment for the neurons

24. Neuroglia Astrocytes 1)Support for neurons 2)Form the blood –brain barrier 3)Learning and memory 4)Maintain the prober environment for the neurons In PNS = Satellite cells

25. Nervous tissue

26. Gray matter : neuron cells White natter: myelinated axons

27. Synapses and Neurotransmitters

28. Communication Between Neurons Synapse:

29. Communication Between Neurons Synapse: A specialized site of contact, and transmission of information between a neuron and an effector cell Figure 45-5 Anterior Motor Neuron

30. Communication Between Neurons Electrical synapse

31. Communication Between Neurons Electrical synapse Chemical synapse

32. Communication Between Neurons Chemical synapse Neurotransmitter: is a messenger of neurologic information from one cell to another.

33. Synaptic Transmission

34. Action of Neurotransmitter on Postsynaptic Neuron postsynaptic membrane contains receptor proteins for the transmitter released from the presynaptic terminal. The effect of neurotransmitter on the post synaptic neuron depend on the type of the receptor

35. Action of Neurotransmitter on Postsynaptic Neuron Two types of receptors –Ion channels receptors

36. Action of Neurotransmitter on Postsynaptic Neuron Two types of receptors –Ion channels receptors –Second messenger receptors

37. Ion Channels receptors transmitters that open sodium channels excite the postsynaptic neuron. transmitters that open chloride channels inhibit the postsynaptic neuron. transmitters that open potassium channels inhibit the postsynaptic neuron.

38. Seconded messenger receptors (as example G-protein) Ion Channel 1.Opening specific ion channels 2.Activation of cAMP or cGMP 3.Activation of one or more intracellular enzymes 4.Activation of gene transcription.