chapter 4 (part 1)
Terms
undefined, object
copy deck
- (JND) just noticeable difference
- the smallest difference in stimulus intensity that a specific sense can detect
- retina contains 2 types of receptors
- 1. rods (black and white) 2. cones (color and daylight vison)
- fovea (visual acuity is greatest here)
- tiny spot in the center of the retina that has only cones
- light enters the eye through the
- cornea (transparent window)
- receptive fields
- areas in the retina that affect the firing of visual cells
- dark adaptation
- the eye becomes more sensitive to light in low illumination
- reversible figure
- drawing that has 2 interpretations that can shift back and forth
- subliminal perception
- registration of sensory input without consciously knowing it
- saturation
-
the relative amount of whiteness in a color (
- optic disk (blind spot)
- a hole in the retina where the optic nerve exits the eye
- inattentional blindness
- failure to see visible objects or events because attention is focused elsewhere (ape in the video)
- top-down processing
- a progression from the whole into it's elements
- perceptual set
- readiness to perceive stimulus in a particular way
- visual agnosia
- inability to recognize objects through site
- k=1/10
- for detecting certain tones
- light adaptation
- eyes become less sensitive to light in high illumination
- absolute threshold
- the minimum stimulus intensity that an organism can detect
- sensory adaptation
- gradual decline in sensitivity to prolonged stimulation (ex; garbage stinks, eventually the smell fades)
- trichromatic theory of color vision
- the human eye there are three classes of cone receptors subserving color vision (receptor level)
- ventral stream
- processes the details of the perception of form and color (what objects are out there)
- feature analysisal input and assembling them into a more complex form
- detecting specific elements in visual input and assembling them into a more complex form
- afterimage
- visual image that persists after a stimulus is removed
- after visual input is processed in the primary auditory cortex, signals travel through 2 streams
- 1. ventral stream 2. dorsal stream
- k=1/60
- for detecting brightness of lights
- complementary colors
- are pairs of colors that produce gray tones when mixed together
- 3 types of color receptors
- 1. red 2. green 3. blue
- perceptions of form involve
- top-down processing
- bottom-up processing
- a progression from individual elements to the whole
- webers law
- applies to all the senses
- lens
- focuses stimuli on the retina
- k=1/4
- for detecting certain odors
- feature detectors
- neurons that respond selectively to specific features of more complex stimuli
- optic chiasm
- the point at which the optic nerves from the inside half of each eye cross over and then project to the opposite half of the brain
- dorsal stream
- perception of motion and depth (where the objects are)
- retina
- lines the inside back surface of the wall, processes images and sends info to the brain
- perception
- interpretation of sensory input into something meaningful (what our brain does)
- opponent process theory of color vision
- color perception depends on receptors that make antagonistic responses to 3 pairs of colors (red vs.green, yellow vs. blue, black vs. white) {neural level}
- subjective contours
- perception of contours where none actually exist (ex; disconnected triangle in text)
- iris
- colored part in eye that regulates the amount of light entering the eye (controls pupil size)
- after reaching the optic chiasm, the optic nerve fibers branch off into 2 pathways
- 1. into the thalamus 2. superior colliculus
- wavelength
- hue
- accommodation
- when the lens adjust to alter visual focus
- amplitude
- height
- amplitude
- brightness
- stimulus
- any detectable input from the environment
- optic nerve
- collection of axons that connect the eye with the brain
- sensation
- the stimulation of sense organs (what our ears and eyes do)
- purity
- saturation
- webers law states
- the change in intensity divided by the original intensity equals a constant
- 2 main purposes of the eye
- channels light to retina (neural tissues) and houses the retina
- psychophysics
- the study of how physical stimuli are translated into psychological experiences
- 3 dimensions of color
- 1. brightness (amplitude) 2. color/hue (wavelength) 3. saturation (purity)