1. Important Concepts in Sensation & Perception

2. Gate Control Theory
Pain signals traveling through the spinal cord have to compete with non-pain signals to reach the brain, and these signals can either be given preference (by Substance P) or be suppressed (by Endorphins).
Broken Leg

3. Weber’s Law
As the intensity of a Stimulus increases, the difference threshold also proportionally increases.
Example 1
Class Chatter (10 decibels) Teacher Taking (13 decibels
Class Chatter (50 decibels) Teacher Talking (53 decibels)
(65 decibels)
Example 2
Holding 1Psych book in one hand Holding 2 Psych Books in other hand
Holding 6 Psych books in one hand Holding 7 Psych Books in other hand 12

4. Absolute Threshold
Minimum amount of stimulation needed to detect a stimulus at least 50% of the time.

5. Kinesthetic Sense
Knowing where your limbs are in space

6. Basilar Membrane
Region within the Cochlea that contains the hair cells that help transduce sound waves into neural impulses for the brain.
Ex. Fans yelling offensive things

7. Signal Detection Theory
Ability to detect Stimuli is influenced by:
(1) Stimulus Variables: Is stimuli weak?
(2) Environmental Variables: Distracting?
(3) Organismic Variables: Person doing detecting

8. Perceptual Set
A predisposition to perceive something one way rather than another
Ex. This team is really good.
Ex. This team sucks.
Ex. This team’s fans are terrible people.
Ex. The porkchops are really good!

9. Gestalt Grouping Principles
Similarity
Proximity
Closure
Continuity
Connectedness

10. Depth Cues Binocular (2 Eyes) - Retinal Disparity - Convergence
Monocular (1 Eye)
-Relative Height
-Relative Size
-Interposition
-Linear Perspective
-Relative Motion
-Light & Shadow
-Texture Gradient
-Relative Clarity

11. Sensory Adaptation
Diminished sensitivity to a constant stimulation.

12. Phi Phenomenon Illusion of movement created by blinking lights.
Link to Example
Stroboscopic Motion- Peoria

13. Perceptual Constancy
Objects remain the same size, shape, & brightness despite changes in the retinal image.

14. Perceptual Adaptation
If exposed to an inverted or altered visual field, you will adjust over time.