Introduction to Nervous system
- 1. Introduction to Nervous System PRESENTED BY : WAJEEHA.
- 2. Introduction to Nervous System 1. What is Nervous System...? 2. Structural Classification of Nervous System 3. Brain a) Location & Functional Division b) Brain Structures & their Functions c) Brain Lateralization 4. Spinal cord a) Peripheral Nervous System b) Somatic Nervous system c) Autonomic Nervous System 5. Basic Functions of the Nervous System a) Integrative Function b) Sensory Function c) Motor Function 6. Neuron 7. Synapse 8. Memory…. 9. Learning & Memory 10. Can I Improve My Memory? 2
- 3. What is Nervous System...? 3
- 4. What is Nervous System...? It is the master controlling and communicating system of the body. The NERVOUS SYSTEM controls and coordinates all essential functions of Human Body. 4
- 5. What is Nervous System...? System of specialized cells (NEURONS or NERVE CELLS) that conduct stimuli from SENSORY RECEPTOR through a “neuron network” to the site (e.g ; a gland or muscle) where the response occurs. A system of NEURONS, NEUROCHEMICALS and ALLIED STRUCTURES involved in receiving sensory information, generating and coordinating responses and controlling bodily activities. 5
- 6. Structural Classification of Nervous System a) Central Nervous System (CNS) It consists of BRAIN and SPINAL CORD which act as integrating and command centers of nervous system. b) Peripheral Nervous System (PNS) They link all parts of the body by carrying impulses from sensory receptors to CNS and from CNS to the effectors. In consists of nerves extending from brain and spinal cord, CRANIAL and SPINAL NERVES. 6
- 7. CNS: 7
- 8. Brain 8
- 9. Location & Functional Division It is located within the cranial cavity of the skull and consists of Divisions of the Brain Major Division Subdivision Structures Telencephalon Neocortex; Basal Ganglia; Amygdala; Hippocampus; Lateral VentriclesProsencephalon (Forebrain) Diencephalon Thalamus; Hypothalamus; Epithalamus; Third Ventricle Mesencephalon (Midbrain) Mesencephalon Tectum; Tegmentum; Cerebral Aqueduct Metencephalon Cerebellum; Pons; Fourth VentricleRhombencephalon (Hindbrain) Myelencephalon Medulla Oblongata; Fourth Ventricle 9
- 10. Brain Structures & their Functions 10
- 11. Cerebral Cortex Brain stem Functions: Thought Voluntary movement Language Reasoning Perception Cerebellum Functions: Movement Balance Posture Functions: Breathing Heart Rate Blood Pressure 11
- 12. Spinal Cord 12
- 13. Spinal Cord It is a reflex center and a conduction pathway which is found within the vertebral canal. It extends from the foramen magnum up to the level of L1 Or L2 . 13
- 15. Peripheral Nervous System It has two divisions Sensory or Afferent Division: Consists of nerve fibers that transmit information from sensory receptors to the CNS. It is further divided into SOMATIC SENSORY & VISCERAL SENSORY nerve fibers. Motor or Efferent Division: Consists of nerve fibers that transmit information from CNS to the effector organs. It is also divided into SOMATIC & AUTONOMIC nervous system. 15
- 16. Somatic Nervous system The somatic nervous system is responsible for coordinating the body movements, and also for receiving external stimuli. It is the system that regulates activities that are under conscious control. 16
- 17. Autonomic Nervous System The autonomic system is for regulating involuntary body functions, such as blood flow, heartbeat, digestion and breathing. This system is further divided into two branches: 1. the sympathetic system regulates the flight-or-fight responses, 2. the parasympathetic system helps maintain normal body functions and conserves physical resources. 17
- 18. Basic Functions of the Nervous System 18
- 19. Basic Functions of the Nervous System 19
- 20. Sensory Function Nervous system uses its millions of sensory receptors to monitor changes occurring both inside and outside the body These changes are called STIMULI, and the gathered information is called SENSORY INPUT 20
- 21. Integrative Function The nervous system processes and interprets the sensory input and makes decision about what should be done at each moment, a process called INTEGRATION. 21
- 22. Motor Function The nervous system then sends information to MUSCLES or GLANDS so that they can respond correctly, such as muscular contraction and glandular secretions. 22
- 23. Neuron THE STRUCTURAL AND FUNCTIONAL UNIT OF NERVOUS SYSTEM 23
- 24. Structure Dendrites: Carry impulses towards the cell body. Receive stimuli from receptors or synapses. Cell Body: contains nucleus and Nissel’s bodies, a form of rough endoplasmic reticulum. Axon: Carry nerve impulses away from cell body. It interacts with glands, muscles or other neurons. 24
- 25. Types of Neurons On the basis of structure, a) Unipolar Neurons b) Bipolar Neurons c) Multipolar Neurons d) Pseudounipolar Neurons On the basis of function, a) Sensory Neurons b) Motor Neurons c) Interneurons 25
- 26. Function Of Neuron Sensory neurons: These neurons tell the rest of the brain about the external and internal environment. Motor (and other output) neurons: Motor neurons contract muscles and mediate behavior, and other output neurons stimulate glands and organs. Interneurons: Communication neurons transmit signals from one brain area to another. 26
- 27. Function of Neuron 27
- 28. Synapse 28
- 29. Synapse In the nervous system, a synapse is a structure that permits a neuron (or nerve cell) to pass an electrical or chemical signal to another cell (neural or otherwise). 29
- 30. Features It is the junction point between one neuron and the next. It determines the direction through which the nerve impulse will spread through the nervous system. Some synapses transmit signals with ease while others don’t. 30
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- 32. Memory…. 32
- 33. Memory…. Storage Information Memory is the process in which information is encoded, stored, and retrieved. Encoding allows information that is from the outside world to reach our senses in the forms of chemical and physical stimuli. 33
- 34. It is just Neurons and some good chemicals….. Memory is, at its simplest, a set of encoded neural connections in the brain. It is the re-creation or reconstruction of past experiences by the synchronous firing of neurons that were involved in the original experience. Our memories are not stored in our brains like books on library shelves, but are actually on-the-fly reconstructions from elements scattered throughout various areas of our brains. 34
- 35. Can I Improve My Memory? 35
- 36. Yes!!!! 36
- 37. How??? 37
- 38. The following techniques take advantage of brain’s storage and retrieval mechanism: Concentrate Minimize interference Break down large amount of information into smaller topic Rephrase material in your own words Test yourself 38
- 39. That’s all… Presented By: Wajeeha. 39