Psychology 3 Flashcards
what is sensation?
sensory organs receive information from environment.
transduction
process when people physical energy is converted into sensory neural impulses.
perception
process when people select organize and interpret sensations
psychophysics
Gustav Fechner. study of the relationship between physical stimulation and subjective sensations.
absolute threshold
smallest amount of stimulation that can to detected. no thresholds are absolute. what can be detected 50% of the time.
signal detection theory
theory that detecting a stimulus is determined by signal and the subject’s response criterion. willingness to say yes or no
just noticeable difference
just enough change for it to be noticeable. smallest amount of change in a stimulus that can be detected 50% of the time.
Weber’s law
principle that the just noticeable difference of a stimulus is a constant proportion despite variations in intensity.
Medium wavelength
greenish
short wavelength
bluish
long wavelength
reddish
amplitude
height of peaks of a light wave determines intensity
wavelength
determines color
purity
measured by number of wavelengths that make up a light wave influences saturation
steps of vision
cornea, iris pupil, lens, vitreous humor, retina, optic nerve ,optic chasm, thalamus, visual cortex
rods
photo receptor highly sensitive to light best in dim light
cones
photoreceptor sensitive to color located in fovea.
fovea
center of retina
trichromatic theory
theory that retina contains 3 types of receptors red blue green these combine to make other colors
opponent process theory
explains color deficiency color deficient people tend to confuse colors. Hering believed that colors are derived from 2 pairs of opposing colors on color wheel. blue-yellow, red- green, black-white
cornea
curved membrane that bends light light comes here first
iris
gives eye color, regulates size of pupil.
pupil
hole in iris where light passes
lens
behind pupil brings image into focus
vitreous humor
jelly like substance fills center part of eyeball like passes here before retina
retina
rods and cones convert light into neural impulses
optic nerve
first part of visual pathway
optic chiasm
where optic nerves meet second part of visual pathway