SELF – STUDY , ESSAY QUESTION Scenario case study

The nervous system divided into the central nervous system CNS and the peripheral nervous system PNS

a. The CNS includes the brain and and spinal cord, which contain nuclei and tracts.

Nuclei are grouping of neuron cell bodies within the CNS. Tract are grouping nerve fibers that interconnect regions of the CNS.

b. The PNS consists of nerves, ganglia and nerve plexuses. Nerve is cablelike collection

of many axons, may be mixed contains both sensory and motor fibers. Ganglia is grouping of neuron cell bodies located outside the CNS 1. Cells of the nervous system The NS is composed primarily of two cell types are found in CNS PNS a. The neuron is the basic structural and functional unit of the NS, which typically consist of a cell body soma, several dendrites, and a single axon. Neuron structure is related to function, which have receptive and integrative zone dendrite and cell body, trigger zone axon hillock, and conductive region axon especially in terminal end of axon has secretive synaptic transmitter. Electrochemical activity in neuron include - Membrane potential: polarization, depolarization, repolarization, hyperpolarization. - Graded electrogenesis: i.e graded potential, receptor potential, EPSP, IPSP. - Site of origin of conducted impuls action potential, all or none transmission, incoming signal in terminal end of the axon as trigger to secreting transmitter synaptic Neuron communicate with muscle, gland, and other neurons at junction its called neuromyal junction, neuroglandular, and synapses. Synapses are found in dendrite, soma, and axon axodendrtic, axosomatic, axoaxonic synapses. b. The four major types of glial cells Neuroglia in the CNS are astrocytes, oligodendrocytes, microglia, and ependymal cells. Glial cells help support the neuron both physically and metabolically. For instance function of the astrocytes as glue, scaffold, establishing blood brain barrier, repair brain injuries and neural scar formation, take up glutamate and GABA, take up excess K+ ECS, and enhance synaptic formation and to strengthen synaptic transmission. oligodendrocytes form myelin sheath, line internal cavity of the CNS contribute to the formation CSF ependymal cells, microglia as scavenger. c. Synaptic transmission involves release of neurotransmitter from the presynaptic cell, diffusion of neurotransmitter across the synaptic cleft and binding of neurotransmitter to receptors on the postsynaptic cell. It ends when the neurotransmitter dissociates from the receptor and is removed from the synaptic cleft. 2. Much of the activity in the NS arises from mechanism that stimulate sensory receptor located at the distal termination of sensory neuron. Signal travel over peripheral nerves to reach the spinal cord and are then transmitted throughout the brain. Incoming sensory massages are processed and integrative with information stored in various pools of neurons such that the resulting signals can be used to generate appopriate motor response

II. SELF – STUDY , ESSAY QUESTION

1. Describe the structure of neuron and explain significance of its principal regions. 2. Classify neurons on the basis of their structure and function. 15 Faculty of Medicine Udayana University, DME 3. Describe the location, the major types, and functions of the supporting cells. 4. Explain how the graded potential and action potential differ 5. Define polarization, depolarization, repolarization and hyperpolarization. 6. Explain the actions of voltage regulated Na+ and K+ channels and describe the event that occur during the production of an action potential. 7. Explain how action potentials are regenerated a long myelinated and non myelinated axon.. 8. Describe the events that occur in the interval between the electrical excitation of axon and the release of neurotransmitter. 9. Compare the characteristics of EPSPs and action potential 10. Explain the synaptic transmission exhibits special characteristic 11. Explain how sensory receptors are categorizeds. Give examples of functional of functional categories and explain how tonic and phasic receptors differ 12. Describe the classification of the sensory division – sensory receptors. 13. Give examples of different types of cutaneous receptors somatosensory receptors and describe the neural pathways for the cutaneous senses 14. Explain how the mechanical energy is tranduced converted into nerve impulses by the organ Corti and how pitch perception is accomplished. 15. Give examples the following modalities are tested : sense of pain, temperatur, touch, vibration, and sense of positition 16. Distinguish between and compare monosynaptic and polysynaptic reflexes.

III. Scenario case study

a A man falls into deep sleep with one arm under his head. This arm is paralyzed when he awakens, but it tingles, and pain sensation in it is still intact 1. What is the reason for the loss of the motor function without loss of pain sensation is that in the nerves to his arm 2. What is a thorough general physical examination should be made in this case. 3. Which one of the sensory test should be done 4. Which one of the reflex test should be done 5. Describe general physical examination should always be done in motor system of this case b Arthritis is common painfull condition caused by inflammation of one or more joints. 1. Why the joint to developed hyperalgesia in this case? c In some diseases of the NS, myelin may be lost over one or more internodes of many axons without interruption of the axon. For instance Guilain – Barre syndrome, diphtheria, and multple sclerosis 1. Why the conduction of nerve impulses may be slowed or blocked. d 74-year-old man suddenly found that he couldnot move his left arm and leg. Examination in the emergency departement demonstrated weakness in the left arm and leg, especially in the distal part of these extremities.The patient also had difficulty in using the muscles of his lower face, and the left side of his tongue was not as strong as the right side. Babinski’s sign was present on the left side. In an examination 1 month later, the distribution of weakness had not changed, although the weakness was not quite as profound. The left biceps, triceps, patellar, and ankle jerk reflexes were markedly increase, and there was ankle clonus on the left. The ability of the patient to recognize tactile and vibratory stimuli was 16 Faculty of Medicine Udayana University, DME reduced on the left side of the face and body and proprioception was impaired in the left arm and leg. 1. Which part of the NS is most likely affected by the stroke? spinal cord on the left, precentral and post central gyri on the right, internal capsul on the right, cerebellar on the left, BG on the right. 2. Which of the following provides evidence indicating that the paralysis is of the spastic type? Day 5 th NEUROPHYSIOLOGY dr. I Dewa Ayu Inten Dwi Primayanti, M. Biomed.

I. ABSTRACT