AP Psychology - Module 18 - Vision

dimension of color determined by wavelengths of light

hue

distance from the peak of one light/soundwave to the peak of the next
Electromagnetic ones vary from short blips of cosmic rays to the long pulses of radio transmission

wavelength

amount of energy in a light/soundwave
perceived as brightness/loudness
determined by wave amplitude

intensity

adjustable opening in the center of the eye through which light enters

pupil

light enters through the ___ and passes through the pupil

cornea

ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

iris

transparent structure behind the pupil that changes the shape to help focus images on the retina

lens

light-sensitive inner surface of the eye, containing rods, cones, and layers of neurons that begin the processing of visual information

retina

process by which the eye's lens changes shape to focus near or far objects on the retina

accommodation

believed fluids in the eye bend light rays, so the image is upright when it reaches the retina

da Vinci

1604, the retina receives the image upside down

Kepler

Convert particles of light energy into neural impulses and forward them to the brain

Receptor cells

In the buried receptors cells of the retina (rods and cones), light energy activates ___, which active ganglion cells

bipolar cells

axons of these cells twist to form the optic nerve to take information to the thalamus to be distributed

ganglion cells

There are no receptor cells where ____, creating a ___

the optic nerve leaves the eye, blind spot

cluster around the fovea
each one transmits to a singular bipolar cell to relay information to the visual cortex, so the fovea input has a large association area. They can detect fine detail, color, and don't work in dim light

cones

central focal point in the retina, around which cones cluster

fovea

share bipolar cells and send combined messages. Peripheral vision. Black and white.

rods

Pressure can trigger the retina, but the brain interprets the subsequent firing as light coming from the ___, activating the __ side of the retina

left, right

feature detection

Hubel and Wiesel

nerve cells in the brain that respond to specific features of the stimulus (shape, angle, movement)

feature detectors

teams of cells (super cell clusters) respond to

complex patterns (gazes, head angle, direction of a ball, anticipating movement)

subdimensions of visual analysis

motion, form, depth, color

Takes up 30% of the visual cortex

facial recognition

Cannot see the sticks, but can report if they are horizontal or vertical

blindsight

order of visual analysis

scene - retinal processing - feature detection - parallel processing - recognition

steps of retinal processing

receptor rods/cones - bipolar - ganglion

feature detection is when

detector cells respond to specific features like edges, lines, angles

brain cell teams process combined information about motion, form, depth, and color
contrasts with serial processing of computers and conscious problem solving

parallel processing

brain interprets the constructed image based on information from stored images

recognition

the retina controls 3 different color receptors, each sensitive to red, green, OR blue. Stimulated in combination allows for perception of any color

Young-Helmholtz trichromatic theory

opposing retinal processes enable color vision
red-green, yellow-blue, white-black. Some cells are stimulated by green and inhibited by red, and vice versa

opponent-process theory

light rays are not

colored

color does not reside in the object but in

our brain

Red and __ messages can't fire at the same time

green

Because red and green messages can't fire at the same time, if you stare at red, you tire the response, and when you look at white, the afterimage is

green