1. The Nervous System Neural Anatomy

2. Neurons: The Building Blocks of the Nervous System
Module 7: Neural and Hormonal Systems

4. Nervous System The electrochemical communication system of the body
Brings information to the brain from the senses
Sends messages from the brain to the body to enact behavior

5. Neuron The basic building block of the nervous system -- a nerve cell
Neurons perform three basic tasks
Receive information
Carry the information
Pass the information on to the next neuron

6. Types of Neurons
Afferents, or “sensory neurons”, carry information from the body to the brain

7. Types of Neurons
Interneurons, found in the spinal cord and the brain, interpret the incoming information and determine the next course of action

8. Types of Neurons
Efferents, or “motor neurons”, carry information from the spinal cord or the brain to the rest of the body in order to initiate behavior

9. Parts of the Neuron

11. Parts of the Neuron - Dendrites

12. Parts of the Neuron - Soma

13. Parts of the Neuron - Axon

14. Parts of the Neuron – Myelin Sheath

15. Parts of the Neuron - Terminals

16. Neuron

17. Neuron

18. How does the whole system fit together?
The Neural Network
How does the whole system fit together?

19. A neuron is considered at “resting potential” when there is no sensory input and it is awaiting stimulus.

20. A Neural Chain

21. Special receptors in each of the five senses detect stimuli from the outside world.

22. When a neuron receives enough information to pass on, it has reached its “action potential” and fires off the message to the next neuron in the link

23. Once a neuron fires, it must re-set momentarily in order to receive another message. This re-set period is called “refraction”. It cannot fire during this period.

24. A Neural Chain

25. Sensory neurons carry all of the input to the spinal cord.

26. A Neural Chain

27. Interneurons in the spinal cord and the brain process the information and decide the best course of behavior.

28. A Neural Chain

29. Motor neurons from the brain travel back down the spinal cord and out to the appropriate parts of the body with the appropriate behavior instructions.

30. A Neural Chain

31. Neural Communication: The Neural Impulse

32. A neuron firing is like a toilet flushing
Like a Neuron, a toilet has a resting potential. The toilet is “charged” when there is water in the tank and it is capable of being flushed.

33. Neuron firing like a Toilet
2. Like a Neuron, a toilet has an action potential. When you flush, an “impulse” is sent down the sewer pipe.

34. Neuron firing like a Toilet
Like a neuron, a toilet has a refractory period. There is a short delay after flushing when the toilet cannot be flushed again because the tank is being refilled
Like a Neuron, a toilet operates on the all-or-nothing principle – it always flushes with the same intensity, no matter how much force you apply to the handle

38. Communication Between Neurons
Module 7: Neural and Hormonal Systems

39. Synapse
The electrical message from the dendrite travels down the axon to the terminal buttons. Here, it changes into a chemical message to be transferred to the next neuron.
The tiny, fluid filled gap between the axon terminal of one neuron and the dendrite of another neuron is called the synapse.

42. Neurotransmitters
A chemical messenger that travels across the synapse from one neuron to the next

43. Neurotransmitters

47. http://depression. emedtv

49. Acetylcholine (ACh)
Enables muscle action, learning, and memory
Undersupply, as ACh-producing neurons deteriorate, marks Alzheimer’s disease

50. Dopamine Influences movement, learning, attention, and emotion
Helps control the brains reward and pleasure center!
Excessive dopamine receptor activity is linked to schizophrenia; a lack of dopamine produces the tremors and lack of mobility of Parkinson’s disease

51. Serotonin Affects mood, hunger, sleep, and arousal
Undersupply is linked to depression; Prozac and other anti-depressants raise serotonin levels

52. Helps to control alertness and arousal
Norepinephrine
Helps to control alertness and arousal
Undersupply can depress mood

53. Endorphins
Natural opiates that are released in response to pain and vigorous exercise
Endorphins

54. Touch Neuron to review

55. The Structure of the Nervous System

56. The Nervous System

57. Central Nervous System (CNS)
The brain and spinal cord
The brain is the location of most information processing.
The spinal cord is the main pathway to and from the brain.

58. Spinal Cord

59. Divisions of the Nervous System

60. Peripheral Nervous System (PNS)
The sensory and motor nerves that connect the central nervous system to the rest of the body
Peripheral means “outer region”
The system is subdivided into the somatic and autonomic nervous systems.

61. Divisions of the Nervous System

62. Somatic Nervous System
The division of the peripheral nervous system that controls the body’s skeletal muscles
Contains the motor nerves needed for the voluntary muscles

63. Divisions of the Nervous System

64. Autonomic Nervous System
The division of the peripheral nervous system that controls the glands and muscles of the internal organs
Monitors the autonomic functions
Controls breathing, blood pressure, and digestive processes
Divided into the sympathetic and parasympathetic nervous systems

65. Divisions of the Nervous System

66. Sympathetic Nervous System
The part of the autonomic nervous system that arouses the body to deal with perceived threats and stress

67. Divisions of the Nervous System

68. Parasympathetic Nervous System
The part of the autonomic nervous system that calms the body
Brings the body back down to a relaxed state

69. Divisions of the Nervous System

70. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

71. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

72. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

73. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

74. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

75. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

76. The Sympathetic and Parasympathetic Divisions of the Autonomic Nervous System

77. The Sympathetic and Parasympathetic Nervous Systems
Physical Responses