1. Biopsychology Domain Andreas Pollok/the Image Bank/Getty images

2. The Nervous System

3. 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.

4. Divisions of the Nervous System

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

6. Divisions of the Nervous System

7. 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

8. Divisions of the Nervous System

9. Autonomic Nervous System The division of the peripheral nervous system that controls the glands and muscles of the internal organs;  its subdivisions are the sympathetic (arousing) division and the parasympathetic (calming) division. – Controls breathing, blood pressure, and digestive processes Automatic processes in the body

10. Divisions of the Nervous System

11. Sympathetic Nervous System The part of the autonomic nervous system that arouses the body to deal with perceived threats. – Fight or flight response

12. Divisions of the Nervous System

13. Parasympathetic Nervous System The part of the autonomic nervous system that calms the body. – Brings the body back down to a relaxed state – Takes time because of chemicals in the body

14. Divisions of the Nervous System

15. Sensation Module 06

16. Module Overview Basic Principles The Visual System Hearing Other Senses Click on the any of the above hyperlinks to go to that section in the presentation.

17. Basic Principles Module 06: Sensation

18. Sensation The process by which sensory systems (eyes, ears, and other sensory organs) and nervous system receive stimuli from our environment. A person’s awareness of the world

19. Basics We turn energies (stimuli) from our environment into neural impulses –The process is called transduction Five senses: –Vision – collecting different wavelengths of light –Hearing – gathering vibrations –Smell – particles floating in the air –Taste – particles in the mouth –Touch – pressure, temperature, & pain Bonus: Balance – body position and limb position

20. Perception The process of organizing and interpreting incoming sensory information. – Figure out what the information means

21. Threshold An edge or a boundary Absolute Threshold – The minimum amount of a stimulation needed to detect a particular stimulus. – Boundary for sensation

22. Signal Detection Theory A theory that predicts how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). – You have heard my voice not the VENT!

23. Sensory Adaptation Diminished sensitivity to constant and unchanging stimulation. If a stimulus is constant and unchanging, eventually a person may fail to respond to it

24. Selective Attention Focusing conscious awareness on a particular stimulus to the exclusion of others. The ability to focus on one stimulus at a time Allows a person to function in a world filled with many stimuli

25. Selective Attention From Leeper, R. W. (1935). A study of a neglected portion of the field of learning: The development of sensory organization. Journal of Genetic Psychology, 46, 41- 75. Reprinted by permission of Taylor & Francis Ltd, http:// www.tandf.co.uk/journals

26. The Visual System: The Structure of the Visual System Module 06: Sensation

27. How Vision Works All light starts as white light –Made up of R O Y G B I V When light hits an object everything is absorbed except the color (wave length) we see

28. Cornea The clear, curved bulge on the front of the eye that bends light rays to begin focusing them. Begins to focus the light by bending it toward a central focal point Protects the eye

29. Parts of the Eye – Cornea

30. Iris A ring of muscle tissue that forms the colored portion of the eye and regulates the size of the pupil. Changes its size--allowing more or less light to enter the eye

31. Parts of the Eye - Iris

32. Pupil The adjustable opening in the center of the iris, which controls the amount of light entering the eye. In bright conditions the iris expands, making the pupil smaller. In dark conditions the iris contracts, making the pupil larger.

33. Parts of the Eye - Pupil

34. Lens A transparent structure behind the pupil in the eye that changes shape to focus images on the retina. Muscles that change the thickness of the lens change how the light is bent thereby focusing the image Glasses or contacts correct problems in the lens’ ability to focus.

35. Parts of the Eye - Lens

36. Nearsightedness and Farsightedness

39. Retina Light-sensitive surface at the back of the eyeball. Contains cells that convert light energy to nerve impulses Made up of three layers of cells – Receptor cells – Bipolar cells – Ganglion cells

40. Parts of the Eye - Retina

41. Receptor Cells Specialized cells in every sensory system of the body that can turn other different kinds of energy into action potentials (neural impulses) that the brain can process. These cells are present in every sensory system to change (transduce) some other form of energy into neural impulses. In sight they change light into neural impulses the brain can understand.

42. Rods Visual receptor cells located in the retina that can detect only black, white and gray. Respond to less light than do cones

43. Cones Visual receptor cells located in the retina that can detect sharp details and color. Need more light than the rods Many cones are clustered in the fovea.

44. Fovea The central focal point of the retina High concentration of cones The spot where vision is best (most detailed)

45. Parts of the Eye - Fovea

46. Rods versus Cones

47. Optic Nerve The nerve that carries visual information from the eye to the occipital lobes of the brain.

48. Parts of the Eye – Optic Nerve

49. Blind Spot The point at which the optic nerve travels through the retina to exit the eye; the lack of rods and cones at this point, creates a small blind spot.

50. Parts of the Eye – Blind Spot

51. Vision Parts –Cornea, Iris/Pupil, Lens, Retina: rods, cones, fovea, Optic Disc (blind spot), Optic Nerve

52. The Visual System: Color Vision Module 06: Sensation

53. Trichromatic (three-color) Theory A theory of color vision that says cones are sensitive to red, green and blue light - the three colors that combine to create millions of color combinations. Based on work of Helmholtz and Young Similar to the design of a color TV

54. Color Vision Normal color vision (trichromatic theory) is made up of three types of cones –Red, blue, green Color-blindness –Dichromatic – only two types of color receptors red/green or green/blue –Monochromatic – one or no color receptors

56. Opponent-Process Theory of Color A theory of color vision that says color is processed by cones organized in opponent pairs (red-green, yellow-blue, black-white); light that stimulated one half of the pair inhibits the other half. Explains the afterimage effect

57. Afterimage Effect

59. Hearing Module 06: Sensation

60. Hearing Parts of the Ear –Pinna –Auditory canal –Eardrum –Hammer, Anvil, Stirrup –Oval Window –Cochlea Cilia –Cochlear Nerve

61. How We Hear!

63. Deafness Conductive Deafness –Equipment doesn’t work properly –Vibrations aren’t making it to the brain –Causes hearing loss associated with damage or age most often Nerve Deafness –Everything works up to the cilia –Messages aren’t forming correctly –Typically, deaf since birth

64. Cochlear Implants Electrodes implanted in the cochlea measures waves in inner ear Send messages to receiver connected to an electrode implanted in the brain Can be removed and hearing ceases Age & motivation affect how “well” hearing develops

65. Vestibular Sense Sense of balance and body orientation –3-D system in the inner ear 3 semicircular canals filled with fluid and crystals (cochlea) –Works like a snow globe –Crystals move and stimulate hairs (cilia) –One canal in each plane (X, Y, Z) gives us body position

66. Other Senses Module 06: Sensation

67. Other Senses: Taste Module 06: Sensation

68. Taste Taste is a chemical sense. Receptor cells are located primarily on the tongue and in the mouth. Four different tastes: – Salty, sweet, sour and bitter Damaged taste receptor cells are replaced within a few days.

69. Supertasters People with an abundance of taste receptors Approximately 25% of the population

70. Nontasters People with a minimum of taste receptors Taste with less intensity than the rest of the population Approximately 25% of the population

71. Other Senses: Smell Module 06: Sensation

72. Smell Smell is a chemical sense. Olfactory cells in the upper nasal passages detect molecules in the air. Taste and smell interact to produce flavor.

73. Olfactory Cells The chemical receptor cells for smell Located in the nasal passages

74. Smell

77. Other Senses: Touch Module 06: Sensation

78. Touch Touch receptors are on the skin Four basic skin senses are – Pain, warmth, cold, and pressure All skin sensations are a combination of these four basic senses

79. Gate-control Theory of Pain Pain messages travel on one set of nerve fibers containing pain gates. The gates are open when pain is felt. Other sensory messages go through another set of fibers. The nonpain fibers can close the pain gates to stop the sense of pain.

80. Other Senses: Body Senses Module 06: Sensation

81. Kinesthetic Sense The system for sensing the position and movement of individual body parts. Relies on receptor cells from the muscles and joints One’s leg “falling asleep” is a disruption of the kinesthetic sense

82. Perception The process of organizing and interpreting incoming sensory information.

83. Grouping The perceptual tendency to organize stimuli into understandable units. Several principles of grouping include: – Similarity – Proximity – Closure – Continuity

84. Grouping - Similarity The tendency to place items that look similar into a group

85. Grouping - Proximity The tendency to place objects that are physically close to each other in a group

86. Grouping – Closure The tendency to look at the whole by filling in gaps in a perceptual field

87. Grouping – Continuity The tendency to perceive that movement of an object continues once it appears to move in a particular direction

88. Illusions Misinterpreting sensory stimuli Help researchers understand how sensation and perception normally works

89. The End