Splash Screen

1. Splash Screen

2. Chapter Introduction Section 1: Sensation Section 2:The Senses Section 3:Perception Chapter Menu

3. Chapter Objectives · Section 1 Sensation Understand that sensations occur anytime a stimulus activates a receptor and that perceptions allow humans to react to their environment. Chapter Preview 1

4. Chapter Objectives · Section 2 The Senses Describe how the sense organs are the receptors of sensations. Chapter Preview 2

5. Chapter Objectives · Section 3 Perception Define perception as the way we interpret sensations and organize them into meaningful experiences. Chapter Preview 3

6. Chapter Preview-End

7. Main Idea Sensations occur anytime a stimulus activates a receptor. Perceptions allow humans to react to their environment. Section 1-Main Idea

8. Vocabulary • sensation • perception • psychophysics • absolute threshold • difference threshold • Weber’s law • signal-detection theory Section 1-Key Terms

9. Objectives • Describe the field of study known as psychophysics. • Define and discuss threshold, Weber’s law, and signal detection. Section 1-Objectives

10. A B C D How many different stimulus are there? A.two B.three C.four D.five Section 1-Polling Question

11. What is Sensation? • Any aspect of or change in the environment to which an organism responds is called a stimulus. • A stimulus can be measured in many physical ways, including its size, duration, intensity, or wavelength. • A sensationoccurs anytime a stimulus activates one of your receptors. Section 1

12. What is Sensation? (cont.) • A sensation can be combined with other sensations and your past experience to yield a perception. • Psychophysics—the study of the relationship between sensory experiences and the physical stimuli that causes them. Fraser’s Spiral Section 1

13. A B C D What are some examples of a perception? A.color corresponds to the wavelength of the light B.brightness corresponds to the intensity C.Both A & B D.None of the above Section 1

14. Threshold • Psychologists conduct experiments to determine the absolute threshold. The Human Senses Gustav TheodorFechner Section 1

15. Threshold (cont.) • The absolute threshold for the five senses is as follows: • Vision—seeing a candle flame 30 miles away on a clear night. • Hearing—hearing a watch ticking 20 feet away. • Taste—tasting 1 teaspoon of sugar dissolved in 2 gallons of water. • Smell—smelling 1 drop of perfume in a 3-room house. • Touch—feeling a bee’s wing falling a distance of 1 centimeter onto your cheek. • ABSOLUTE THRESHOLD ACTIVITY Section 1

16. A B C D What is our vestibular sense? A.Spatial movement B.Gravitational pull C.Movement and position of body parts D.None of the above Section 1

17. Sensory Differences and Ratios • The difference threshold is the smallest change in a physical stimulus that can be detected between two stimuli half the time. • The just noticeable difference (JND) refers to the smallest increase or decrease in the intensity of a stimulus that a person is able to detect half the time. Section 1

18. Sensory Differences and Ratios (cont.) • A particular sensory experience depends more on the changes in the stimulus than on the absolute size or amount. • Weber’s law: the larger or stronger a stimulus, the larger the change required for a person to notice that anything has happened to it. Section 1

19. A B C D How would you rate your sense of smell? A.I smell the slightest odors B.I can smell most odors C.I smell only very strong odors D.Not even a skunk would bother me Section 1

20. Sensory Adaptation • Our senses have an ability to adapt, or adjust themselves, to a constant level of stimulation. • They get used to a new level and respond only to deviations from it. The Disappearing Circle Section 1

21. A B C D What is the purpose of sensory adaptation? A.notice differences in sensations B.react to the challenges of different stimuli C.react to the challenges of changing stimuli D.All of the above Section 1

22. Signal-Detection Theory • The single-detection theory is the study of people’s tendencies to make correct judgments in detecting the presence of stimuli. • Detection thresholds involve recognizing some stimulus against a background of competing stimuli. Section 1

23. Signal-Detection Theory (cont.) • The concept of absolute threshold: the stimulus (a signal) must be detected in the presence of competing stimuli, which can interfere with detection of the signal. Section 1

24. Signal-Detection Theory (cont.) • Psychologists have identified two different types of processing stimuli: • Preattentive process • Attentive process The Stroop Effect Section 1

25. What are some reasons that “we notice some things automatically in spite of distracting information”? A.Preattentive process B.The Stroop Effect C.Attentive process D.None of the above • A • B • C • D Section 1

26. Section 1-End

27. Main Idea The sense organs—the eyes, ears, tongue, nose, skin, and others—are the receptors of sensations. Section 2-Main Idea

28. Vocabulary • pupil • lens • retina • optic nerve • binocular fusion • retinal disparity • auditory nerve • vestibular system • olfactory nerve • kinesthesis Section 2-Key Terms

29. Objectives • Describe the nature and functioning of the sense organs. • Identify the skin and body senses and explain how they work. Section 2-Objectives

30. A B C D What are some internal senses? A.vestibular B.skin C.kinesthetic D.touch Section 2-Polling Question

31. Vision • How does vision occur? • Light enters the eye through the pupiland reaches the lens, which focuses light on the retina. • The retina contains tow types of light-sensitive receptor cells, or photoreceptors: rods and cones. The Human Eye Section 2

32. Vision (cont.) • Rods: sensitive to much lower levels of light and are the basis for night vision. • Cones: work best in the daylight and are sensitive to color. • These cells are responsible for changing light energy into neuronal impulses. • Impulses travel along the optic nerve to the brain, where they are routed to the occipital lobe. Section 2

33. Vision (cont.) • Visible light is composed of waves of different length and frequency (observable with a prism). • A prism transmits light while other objects absorb and reflect light. • When some or all of a person’s cones do not function properly, he or she is said to be color deficient. The ElectromagneticSpectrum Testing for ColorDeficiency Section 2

34. Vision (cont.) • Binocular fusion—the process of combining the images received from the two eyes into a single, fused image. • There is a difference between the images on the retinas, called retinal disparity. Section 2

35. Vision (cont.) • Nearsightedness—having an eyeball that is too long, which causes problems seeing objects that are distant. • Farsightedness—having an eyeball that is too short, which causes problems seeing up close. A Changing Flag Section 2

36. A B C D If you have good night vision, you could be described as having _____. A.sensitive cones B.sensitive rods C.binocular fusion D.farsightedness Section 2

37. Hearing • Hearing is caused by sound waves that pass through various bones until they reach the inner ear, which contains tiny hairlike cells that move back and forth. • These hair cells change sound vibrations into neuronal signals that travel through the auditory nerve to the brain. Decibel Levels Section 2

38. Hearing (cont.) • The auditory nerve carries impulses from the inner ear to the brain, resulting in the perception of sound. • Sound pressure energy is measured in decibels. • Pitch depends on sound-wave frequency. The Human Ear Section 2

39. Hearing (cont.) • Two types of deafness: • Conduction deafness • Sensorineural deafness Section 2

40. A B C Which of the following is more likely to be caused by exposure to loud music? A.Conduction deafness B.Sensorineural deafness C.Neither Section 2

41. Balance • The body’s sense of balance is regulated by the vestibular system inside the inner ear. Section 2

42. A B C D What happens when the vestibular sense is overstimulated? A.spinning B.dizziness C.motion sickness D.all of the above Section 2

43. Smell and Taste • Smell and taste are referred to as the chemical senses because their receptors are sensitive to chemical molecules. • In order to smell, the appropriate gaseous molecules must come into contact with the smell receptors in your nose. • These receptors send messages about smells through the olfactory nerve to the brain. Section 2

44. Smell and Taste (cont.) • Olfactory nerve—the nerve that carries smell impulses from the nose to the brain. • In order to taste, appropriate liquid chemicals must stimulate receptors in the taste buds on your tongue. • Taste information is relayed to the brain, along with data about the texture and temperature of the substance in your mouth. Section 2

45. Smell and Taste (cont.) • Four primary sensory experiences—sour, salty, bitter, and sweet—make up taste. • Smell plays a large role in taste. • The combining of taste, smell, and tactile sensations is known as flavor. The Human Tongue Section 2

46. A B C D Which of the four primary sensory experiences are you most sensitive to? A.Sour B.Salty C.Bitter D.Sweet Section 2

47. The Skin Senses • Receptors in the skin are responsible for sensing pressure, warmth, cold, and pain. Section 2

48. The Skin Senses(cont.) • There are two types of pain sensations: • The sharp, localized pain you may feel immediately after an injury. • The dull, generalized pain you may feel later. Section 2

49. The Skin Senses(cont.) • Gate control theory of pain: we can lessen some pains by shifting our attention away from the pain impulses. • This limits the number of impulses that can be transmitted, and can dull the pain. Section 2

50. A B Which of the following are you more sensitive to? A.Warmth B.Cold Section 2