PSY 200 Test 2

Any detectable input from the environment

the minimum stimulus intensity that an organism can detect

the smallest difference in stimulus intensity that a specific sense can detect (shades of paint)

the detection of stimuli involves decision processes as well as sensory processes- Which are both influenced by a variety of factors besides stimulus intensity.

detecting signals when they are present

detecting signals when they are not present

not detecting signals when they are absent

detecting signals when they are not present

the registration of sensory input without conscious awareness- subliminal messages

A gradual decline in sensitivity to prolonged stimulation- smell of pot smoke starts to fade

Built in process that keeps people tuned in to the changes rather than the constants

a form of electromagnetic radiation that travels as a wave- moving at the speed of light

Amplitude(height)- brightness wavelength(distance between peaks)- color

The neural tissue lining the inside back surface of the eye; it absorbs light, processes images, and sends visual information to the brain.

Transparent "window" at the front

controls amount of light reaching the retina

the opening in the center of the iris that permits light to pass into the rear chamber of the eye

Bright Light- Constrict

Dim Light- Dilate

the transparent eye structure that focuses the light rays falling on the retina

close objects are seen clearly but distant objects appear blurry- Light from distant objects focuses in front of the retina

eyeball to long

A vision de
ciency in which distant objects are seen clearly but close objects appear blurry- Light from close objects focuses behind the retina.

eyeball to short

Specialized visual receptors that play a key role in daylight vision and color vision- concentrated most heavily in the retina

tiny spot in the center of the retina that contains only cones; visual activity is greatest at this spot. (when you want to see something sharply, centered on the fovea)

Specialized visual receptors that play a key role in night vision and peripheral vision- greatly outnumber cones in the periphery of the retina

density of rods greatest just outside the fovea

process in which the eyes become more sensitive to light in low illumination

Process whereby the eyes become less sensitive to light in high illumination

A hole in the retina where the optic nerve fibers exit the eye (known as the blindspot)

Occurs when neural activity in a cell opposes activity in surrounding cells (allows the retina to compare the light falling in a specific area against general lighting.

the retinal are that, when stimulated, affects the firing of that cell.

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.

Processes information about motion and depth- moves on to areas of parietal lobe.

Processes information about color and form- moves on to areas of temporal lobe

The human eye has three types of receptors with differing sensitivities.

Only have two types of color receptors instead of three

Colors that produce gray tones when mixed together.

Blue

Green

Red

A readiness to perceive a stimulus in a particular way (creates a slant in how someone interprets sensory input)

Failure to see visible objects or events because one's attention is focused elsewhere.

A progression from individual elements to the whole

a progression from the whole to the individual elements

involves the perception of contours where none actually exist

The illusion of movement created by presenting visual stimuli in rapid succession (like a movie or cartoon)

Figure is the thing being looked at- ground is the background against which it stands

Things that are near one another seem to belong together

You may complete figures that actually have gaps in them

People tend to group stimuli that are similar.

Most general principle of Gestalts- Idea that people tend to group elements that combine to form a "good figure".

The principle reflects peoples tendency to follow whatever direction they've been led.