Vocabulary List Flashcards
Sensation “Detection & Encoding”
The senses collect some kind of information from the environment and convert it to a signal that can travel to the brain
-Sensing our environment through touch, taste, sight, sound, and smell (nervous system)
-Our senses depend on each other
Perception “Interpretation”
Process by which we select, organize, and interpret sensory information in order to recognize meaningful objects and events
-Information is organized, interpreted, and consciously experienced
-Enables recognition of meaningful events
Bottom-Up Processing “Sensory Analysis”
Involves starting with an incoming stimulus and working upwards until a representation of the object is formed in our minds
-Begins at entry level with our senses can detect
-Requires no previous knowledge or learning
Top-Down Processing
Form our perceptions starting with a larger object, concept, or idea before working our way toward more detailed information
-Big Picture, Tiny Details
-Influenced by prior experience and current expectations
Absolute Threshold
Smallest level of stimulus that can be detected, usually defined as at least half the time (Point something becomes noticeable)
-How dim can a light be or how soft can a sound be and still be detected half of the time
Signal Detection Theory
Theory predicting how and when we detect the presence of a faint (weak) stimulus (signal) amid background stimulation (noise)
-Assumes there is no single absolute threshold, detection depends partly on a person’s experience, expectations, motivation, and level of fatigue
Subliminal Sensation
When stimuli are below one’s absolute threshold for conscious awareness
-Much of our information processing occurs automatically, out of sight, off the radar screen of our conscious mind
Difference Threshold “Just Noticeable Difference (JND)”
The amount something must be changed in order for a difference to be noticeable, or detectable at least half the time
Weber’s Law
The principle that to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than constant amount)
-Bigger stimuli require larger differences to be noticed
-Light, 8%
-Weight, 2%
-Tone, 3%
Sensory Adaptation
Reduction in sensitivity to a stimulus after constant exposure to it
-Reduces our awareness of a constant stimulus, it helps free up our attention and resources to attend to other stimuli in the environment around us
Selective Attention
We center our attention on certain important elements of our environment while other things blend into the background or pass us by completely unnoticed
-We sense a lot of information. Scientists estimate we observe 11,000,000 its of info per second. But we weed out all but 40 bits
Divided Attention “Multitasking”
Occurs when mental focus is on multiple tasks or ideas at once
-Divided attention does decrease the amount of attention being placed on any one task or idea is there are multiple focuses going on at once
Inattentional Blindness
When our focus is directed at one stimulus, leaving us blind to other stimuli.
Change Blindness
The inability to see changes in our environment when our attention directed elsewhere.
Psychophysics
The study of the relationship between stimuli and our responses to them.
Priming
Using cues to activate hidden memories.
Wavelength
the distance from the peak of one light or sound wave to the peak of the next.
Feature Detectors
In the visual cortex, specialized neurons that react to the strength of visual stimuli, responding to shapes, angles, edges, lines, and movement in field of vision
Opponent-Process Theory
Retinal processes only occur in 3 sets of opponents
-Red-Green Complex
-Blue-Yellow Complex
-Black-White Complex
-Cells can only detect the presence of one color at a time because the two colors oppose one another
Color-Deficient Vision
Simply lacking functioning-red or green-sensitive cones or sometimes both, missing cones that respond to a specific color
-Monochromatic (one-color) or dichromatic (two-color) instead of trichromatic, making it impossible to distinguish the red and green.
Young-Helmholtz Trichromatic (three-color) Theory
There are three receptors in the retina responsible for the perception of color (green, blue, red)
-Colors red, blue, and green can be combined to create all colors of light
Blind Spot
The point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there
-Sacade, eyes have rapid movement from side to side to help fill in the missing information created by the blind spot.
Cones
Light-detecting cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions, directly involved in our ability to perceive color
Rods
Specialized photorecpetors that work well in low light conditions, involved in our vision in dimly lit environments as well as in our perception of movement on the periphery of our visual field
Photorecpetors
Convert light energy to electrochemical neural impulses that are conducted to our brain
-Rods and Cones
-Our retinal contains 120 million rods and 1 million cone receptors
Transduction
The transformation of stimulus energy to electrochemical energy of neural impulses (except smell)
