Sensation and Perception Flashcards
Perception
How you understand your environment by interpreting your sensations
**associated with top-down processing
Sensation
How you experience your environment by bringing in energy through your eyes, ears, etc.
**associated with bottom-up processing
Bottom-Up Processing
Analysis that begins with sensory receptors and works up to the brain’s integration of sensory info
- new
- *detecting lines, angles, and colors that form the horses, riders, and surroundings
Top-down processing
Guided by higher level mental process, such as experience, motivation, and expectations
- old
- *consider the painting’s title, notice the apprehensive expressions, and attend to aspects that give meaning
Perceptual adaptation
Ability to adjust to an artificially displaced visual field
Psychophysics
The study of how physical energy relates to our psychological experience
Transduction
Conversion of one form of energy into another
Absolute threshold
The minimum stimulation needed to detect a particular stimulus 50% of the time
**basically tells us absolute limit of our sensation
Difference threshold
The minimum difference a person can detect between any two stimuli half the time
**also called just noticeable difference
Weber’s Law
Difference thresholds differ by a percentage rather than amount
Signal detection theory
Predicts when we will detect a particular stimulus amid competing background stimuli
Subliminal messages
Anything below our absolute threshold
Sensory adaptation
Decreased sensation due to constant stimulation
Intensity (brightness)
height of a wave
hue (color)
length of the wave
long-red
short-blue
pupil
adjustable opening in the center of the eye, lets light in
iris
a ring of muscle that forms the colored portion of the eye around the pupil and controls the size of the pupil opening
cornea
protects the eye and bends light to provide focus
lens
transparent structure behind pupil that changes shape through accommodation to focus images on the retina
retina
the light-sensitive inner surface of the eye, contains receptor rods and cones plus layers of neurons that begin the process of visual info
optic nerve
nerve that carries neural impulses from the eye to the brain
blind spot
point at which the optic nerve leaves the eye, creating a “blind spot” because there are no receptor cells there
fovea
central point in the retina, around which the eye’s cones cluster
acuity
sharpness of vision
nearsightedness
far blurry
farsightedness
near blurry
how does light energy reach the brain?
light energy –> rods and cones –> bipolar cells –> ganglion cells (axons form the optic)
rods
peripheral of retina
detect black, white, and gray
twilight or low light