1. Unit 4: Sensation and Perception
Mr. McCormick
A.P. Psychology

2. Essential Question
How do people use the 7 known senses to understand the world around them?

3. Unit 4(A): Sensation, Perception, and Attention
Mr. McCormick
A.P. Psychology

4. Do-Now (Discussion)
Open your textbooks to Pg. 229: “Sensation and Perception”
What is Prosopagnosia?
How does this condition illustrate the difference between sensation and perception?

5. Sensation and Perception
The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment
“Bottom-Up”
Perception:
The process or organizing and interpreting sensory information, enabling us to recognize meaningful objects and events
“Bottom-Up” and “Top-Down”

6. Sensation and Perception: “Bottom-Up” Vs. “Top-Down”
“Bottom-Up” Processing:
“Top-Down” Processing:
T E C T

7. “The Forest Has Eyes” Bev Doolittle

8. Sensation and Perception: “Bottom-Up” Vs. “Top-Down”
Look at the images on Hand-Out 6-12:
What does each image represent
Which process is “Bottom-Up?”
Why?
Which process is “Top-Down?”

9. Sensation and Perception
Organisms are equipped with sensory and perceptual abilities based upon their individual needs:
A frog, which feeds on flying insects, has eyes with receptor cells that fire only in response to small, dark, moving objects. A frog could starve to death knee-deep in motionless flies. But let one zoom by and the frog’s “bug detector” cells snap awake.
A male silkworm moth has receptors so sensitive to the female sex-attractant odor that a single female need release only a billionth of an ounce per second to attract every male silkworm moth within a mile. That is why there continue to be silkworms.
Humans are similarly equipped to detect the important features of our environment. Our ears are more sensitive to sound frequencies that include human voice consonants and a baby’s cry.

10. Perception and Selective Attention
The focusing of conscious awareness on a particular stimulus
The five senses take in 11,000,000 bits of information per second; however, people consciously process 40 bits.

11. Perception and Selective Attention
Inattentional Blindness:
Failing to see visible objects when our attention is directed elsewhere
Simons and Chabris:
“Gorilla Study” (1999)
50% of participants failed to consciously perceive gorilla
Change Blindness:
Failure to notice changes in the environment
Simons and Levin:
“Door Study” (1998)
50% of participants failed to consciously perceive change of actor
Inattentional/Change Blindness:

12. Review What is the difference between sensation and perception?
How do sensation and perception help us understand the world around us?
What is selective attention?
Differentiate between inattentional blindness and change blindness.

13. Homework Chapter 6 Outline: “Sensation and Perception”
Unit 4 Key People
Research Study Response #5: “Take a Long Look” (Pgs )
Unit 4 Quiz: “Sensation and Perception