1. Sensation and Perception
Chapter 3

2. Sensation
The process that occurs when special receptors in the sense organs are activated, allowing stimuli
What are the 5 senses?

3. Perception
The method by which the sensations experienced at any given moment are interrupted and organized in some meaningful fashion
When your brain collects data, organizes it, and interprets it to give those sensations meaning
Examples?

4. Just Noticeable Difference
AKA Difference Threshold
Ernst Weber
The smallest different between two stimuli that is detectable 50 percent of the time by 50 percent of the people tested
Read example on the top of page 79
Class demonstration

5. ABSOLUTE THRESHOLD
THE LOWEST LEVEL OF STIMULATION THAT A PERSON CAN CONSCIOUSLY DETECT 50 PERCENT OF THE TIME THE STIMULATION IS PRESENT
The brain is only interested in changes in information

6. HABITUATION Although you may hear something, you may not notice it
How your brain deals with unchanging information from the environment
Very similar to sensory adaptation – tendency of sensory receptor cells to become less responsive to a stimulus that is unchanging
Without sensory adaptation the trash would never stop smelling, the noises would never stop being annoying, and the clothes would never be comfortable.
Video
Class demonstration

7. SENSORY RECEPTORS
Receptor cells are stimulated by different kinds of energy
Page 80
Some things we can’t see, hear, feel
If you had to give up one of your senses, which one would it be and why?

8. Perception
The method by which the brain takes all the raw data sensations people experience at any given moment and allows them to be interpreted in some meaningful fashion in the brain
Help us interact with our environment

9. Perceptual Constancies
There are 3
Size constancy – the tendency to interpret an object as always being the same size, regardless of its distance from the viewer

10. Perceptual Constancies
Shape constancy – interpret the shape of an object as a constant, even when it changes on the retina
Why a person still perceives a coin as a circle even if it is held at an angle that makes it appear to be an oval on the retina

11. Perceptual Constancies
Brightness constancy – the tendency to perceive the apparent brightness of an object as the same even when the light conditions change
Dark day – bright day

12. Gestalt Psychology
Believes that people naturally seek out patterns (“wholes”) in the sensory information available to them
Figure ground – tendency to perceive objects or figures as existing on a background
Reversible figure – the figure and the ground seem to switch back and forth

17. Proximity
Tendency to perceive objects that are close to one another as part of the same grouping
Similarity – tendency to perceive things that look similar as being part of the same group
Closure – the tendency to complete figures that are incomplete
Continuity – tendency to perceive things as simply as possible with a continuous pattern rather than with a complex, broken up pattern
Contiguity – the tendency to perceive two things that happen close together in time as being related
Figure on page 96

18. Depth Perception Ability to see the world in three dimensions
The Visual Cliff on page 97 – read it and answer questions
Monocular vs. binocular cues

19. Pictorial Depth Cues
Break up the 7
Teach class

20. Binocular Cues
Convergence – making a triangle with you eyes to converge on one object
Binocular disparity – two different eyes two inches apart see different things

21. Illusion Perception that does not correspond with reality Video
Figure 8.5 on page 99 – which line is longer?
Auto kinetic effect – light moving in a dark room
Stroboscopic motion – flip books still pictures will seem to move
video

22. Perceptual set or expectancy
People’s tendency to perceive things a certain way because of previous experiences or expectations influence them
Class demonstration page 100
Figure 8.6 on page 100

23. Perceptual set
Top-down processing – the use of preexisting knowledge to organize individual features into a unified whole.
Ex: completing a puzzle – putting together a table
Bottom-up processing – analysis of smaller features and building up to a complete perception
Ex: no puzzle top – no directions of completed table
Video
Subliminal advertising page 101
Practice quiz page 102