2 GENERAL INTRODUCTION TO NERVOUS SYSTEM’.pptx

Medical

1. GENERAL INTRODUCTION TO NERVOUS SYSTEM DR ARVIND PAIKRAO Professor & HOD, Dept of Kriyasharir , VPAMC, Vadnagar-384355.

2. Nervous System Parts Central Nervous System Peripheral Nervous System 16-Jun-23 2 Prof. Dr Arvind VPAMC, Vadnagar

3. CENTRAL NERVOUS SYSTEM The central nervous system consists of; Brain & Spinal C ord . 16-Jun-23 3 Prof. Dr Arvind VPAMC, Vadnagar

4. THE BRAIN The brain is situated in the skull and furthermore, it is main part of the central nervous system. It is divided or composed of fore brain, mid brain & hind brain. 16-Jun-23 4 Prof. Dr Arvind VPAMC, Vadnagar

5. Fore-brain I t is made of Telencephalon & Diancephalon . Telencephalon made of four parts the cerebral hemisphere also known as cerebral cortex, limbic forebrain structures, the basal ganglia, & the olfactory system. Diancephalon consists of two major structures the thalamus & hypothalamus and two smaller structures the epithalmus & subthalmus . 16-Jun-23 5 Prof. Dr Arvind VPAMC, Vadnagar

6. Mid-brain It is top most part of the brainstem, the connection central between the brain & spinal cord. There are three main parts of the midbrain; the colliculi , the tegmentum & cerebral peduncles. This part is also known as mesencephalon , i.e the region of developing brain that composed of tectum & tegmentum . The midbrain serves important functions in the motor movements of the eye and in auditory & visual processing. 16-Jun-23 6 Prof. Dr Arvind VPAMC, Vadnagar

7. Hind-brain The hindbrain (developmentally derived from the rhombencephalon ) is one of the three major regions of our brains, located at the lower back part of the brain. It includes most of the brainstem and a dense coral-shaped structure called the cerebellum. So there are three main parts of the hindbrain -  Pons , Cerebellum , and Medulla oblongata . 16-Jun-23 7 Prof. Dr Arvind VPAMC, Vadnagar

8. Spinal Cord 16-Jun-23 8 Prof. Dr Arvind VPAMC, Vadnagar

9. BASIC FUNCTIONS OF CNS There are main three function of nervous system as; It collect the information from the environment or external world and information from the body or all bodily parts trough the sensory inputs. It compares & contrast this received recent information with the past experiences. Integrate it, process it at higher level and generate the decision to tackle for. In response with the sensory input generate the motor response, i.e run away from difficult situation or glandular secretions. 16-Jun-23 9 Prof. Dr Arvind VPAMC, Vadnagar

10. PERIPHERAL NERVOUS SYSTEM Peripheral nerves reside outside your brain and spinal cord. They relay information between our brain and the rest of body. It collects sensory information through sensory input. Send the motor or effect in response with sensory input through motor system. Some information going to CNS recognized at conscious level & some information do not cognized at your conscious level. The information perceived by cerebral cortex are considered as the conscious level cognition; in other hand the information does not reach at cerebral cortex are considered as the unconscious level perception. For example blood pressure sensation is unconscious level information, you are actually not aware of it. 16-Jun-23 10 Prof. Dr Arvind VPAMC, Vadnagar

11. Main Division Peripheral Nervous System divided into two parts; Sensory Peripheral Nervous System Motor Peripheral Nervous System 16-Jun-23 11 Prof. Dr Arvind VPAMC, Vadnagar

12. Sensory PNS divided into two types 16-Jun-23 12 Prof. Dr Arvind VPAMC, Vadnagar

13. Special Sensations Special sensations:- special sensations are defined as they are the sensations which are generated from the special part of the body. For example vision only can be perceived by eyes not by ear or other sensory faculties. These are as follow as; Vision- only by eyes Olfaction – only by nose Taste – only by tongue Hearing- only by ears Sense of balance, equilibrium and position only by vestibule part of ear. 16-Jun-23 13 Prof. Dr Arvind VPAMC, Vadnagar

14. General Sensations General Sensations :- the general sensations are elicited from many part of the body for example pain, touch, vibration can be elicited form many part of the body. These are again divided as follow as; Somatic sensations:- Visceral sensation:- 16-Jun-23 14 Prof. Dr Arvind VPAMC, Vadnagar

15. Somatic Sensations Pain:- unpleasant sensation Temperature:- cold & warm Touch:- fine & crude Vibration:- to & fro movement etc. Proprioceptions :- it is the sensation of the skin, subcutaneous tissue, fascia and loco motor system as like; skeletal muscles, joints ligaments tendons and perceiving the sensation of the position in the space. 16-Jun-23 15 Prof. Dr Arvind VPAMC, Vadnagar

16. Visceral Sensation Abdominal cramps Dull pain Discomfort due to distance of the viscera etc. 16-Jun-23 16 Prof. Dr Arvind VPAMC, Vadnagar

17. Motor Peripheral Nervous System Division Voluntary Motor PNS Involuntary Motor PNS 16-Jun-23 17 Prof. Dr Arvind VPAMC, Vadnagar

18. Voluntary Motor PNS Voluntary Motor PNS:- the information perception at our conscious level or under our will control which are also called somatic motor responses. The activity carried out by skeletal muscles, for example forwarding of our hand to take tea. 16-Jun-23 18 Prof. Dr Arvind VPAMC, Vadnagar

19. Involuntary Motor PNS Involuntary Motor PNS:- in this information is perceived at your unconscious level which is not controlled under your will power which are also called as automatic response or autonomic response. This is carried out by smooth muscles for example the peristalsis in GI tract which do not controlled under your will power. 16-Jun-23 19 Prof. Dr Arvind VPAMC, Vadnagar

20. Involuntary Motor PNS is again divided into two types as ; Parasympathetic Nerve System: - activity without your will power when someone is not in stress (without stress) for example GI tract activity. Sympathetic Nerve System:- activity without your will power when you are in stress (with stress) for example fight flight responses. 16-Jun-23 20 Prof. Dr Arvind VPAMC, Vadnagar

21. SOME IMPORTANT TERMS..! Gray matter:- collection of the cell body of neuron within the central nerves system is called gray matter. White matter:- collection of axon or bundle of axons within the central nerves system is called white matter. They are tail of neurons or they are axons. Tracts:- bundle of axons or collection of axon within the central nerves system are called tracts. The bundle of axon moving towards the central nervous system or brain are called sensory tract. The bundle of axon or collection of axon moving away from the central nervous system are called motor tract. Commissural fiber:- bundle of axon or the collection of axons which are the connection of central nervous system between right to left or left to right are called commissural fibers. Corpus coliseum is the largest commissural fiber in the central nervous system. 16-Jun-23 21 Prof. Dr Arvind VPAMC, Vadnagar

22. SOME IMPORTANT TERMS..! Association fibers:- bundle of axon or the collection of the axon which connect or communicate the central nervous system antero-posteriarly or posterior- anteriarly i.e. front back or back to front communication of central nervous system are called association fiber. For spinal cord the gray matter situated inside while white matter is located outer part of the spinal cord. In the cerebrum & cerebellum the white matter is situated inner part & gray matter situated outer part of them. Cerebral Coretex :- the gray matter applied at the surface of forebrain (cerebral hemisphere) is called ceberal cortex, similar is found in the cerebellar cortex. Nucleus:- pieces of the gray matter embedded or situated in deepest part of central nervous system and which is surrounded by white matter is called nucleus. 16-Jun-23 22 Prof. Dr Arvind VPAMC, Vadnagar

23. SOME IMPORTANT TERMS…! Basal Nuclei:- collection of gray matter in the central nervous system surrounded by white matter in the base of cerebral hemisphere is called basal nuclei. Reticular formation:- due to decussation i.e the crossing of the ascending tract & descending tract the gray matter in the central nervous system breaks down into small pieces is called reticular formation. Some of these pieces breaks down into larger masses are called nuclei of the cell, for example third nerve nuclei. Nerve:- the bundle of axon or the collection of axons outside of the central nerves system are called nerve. Around the axon of the nerve there are Schwann cells present while around the white matter & different tracts no Schwann cell are seen instead some other special cells are present are called oligodendrocytes . 16-Jun-23 23 Prof. Dr Arvind VPAMC, Vadnagar

24. DR ARVIND PAIKRAO Professor & HOD, Dept of Kriyasharir , VPAMC, Vadnagar-384355. 24 Prof. Dr Arvind VPAMC, Vadnagar 16-Jun-23