Quiz for Mar 16th & 30th

Photoreceptors

cells in retina perform transduction

Rods

highly sensitive to light, works primarily best in black and white

Cones

better in bright light and concentrated in fovea (center)

Photoreceptors, Bipolar, and Ganglion cells

three layers of eye cells

Bipolar neurons

pass signals from photo-receptors to ganglions

Ganglion cells

on surface of retina, generate action potentials, make up optic nerve

Transduction

process of transferring messages from one space of energy to another

Trichromatic theory

cones are most sensitive to wavelengths corresponding to blue, green and red

Opponent-Process theory

color sensitive visual elements are grouped into pairs

Dual-Process theory

combines two theories for color perception

Dichromats

colorblind in one of the three systems

Monochromats

VERY colorblind

Figure Ground and Grouping

two principles of influencing perceptual organization

Figure Ground

organizing stimuli into figure against background

Similarity, proximity, closure, and continuity

Four principles of grouping

Size constancy

changes in size of retinal image is interpreted as changes in distance

Shape Constancy

perceived shape of an object remains the same, even when seen at diff angles

Brightness/Color Constancy

brightness or color of object remains same under diff conditions of light

Depth Perception

distance between objects and how near or far they are

binocular and monocular

two types of cues

Binocular Depth cues

requires use of both eyes

Eye convergence

produced by feedback from muscles in eyes

Binocular diversity

retinal disparity, each eye sees slightly different image

Monocular depth cues

cues of distance that only needs one eye

Pictorial Depth cues

cues about distance that can be given in a flat picture

Linear perception

parallel lines converge in the distance

Interposition

objects closer to use may cut off part of our view of more distant objects

Elevation

height in plane, horizontal plane

Texture gradient

closer objects are more detailed

Relative size

if two objects are of similar size, one that looks smaller will be judged as further away

Non pictorial cues

Motion parallax and ocular accommodation

Two types of motion

Real and Apparent

Stroboscopic motion

illusion of motion created when we see slightly different images in rapid succession

Auto kinetic Effect

perceived motion created by a single stationary object, light that’s still looks like it’s moving

Conciousness

awareness on self and environment

Circadian rhythms

24 hour bio cycles found in many species

N1: Light sleep

lasts about 10-12 min, brain wave pattern is irregular

N2: Deeper level of sleep

transitional phase, lasts about 10-25 min, characterized by sleep spindles, brief bursts of brain wave activity, lasts 1-2 seconds

N3: Deep sleep

slow wave sleep, deepest lvl, delta waves dominate, takes less than an hour to get to the stage, difficult to wake up, groggy and confused

N2

What happens after N3?

Paradoxical sleep

body is highly aroused yet there’s very little movement

REM rebound effect

increased amount of REM after being sleep deprived

Signs of sleep deprivation

errors, injuries, lowers immune system, automobile accidents

Narcolepsy

abrupt shift from waking state into REM sleep, often while laughing or other emotional state

Sleep terrors

horrific nightmares during N3, symptom: blood curdling scream, no recall in the morning

Sleepwalking

somnambulism, occurs during N3, usually in childhood

REM sleep disorder

normal REM sleep doesn’t occur, they move and act out dreams

Opiates

relieves pain

Psychopharmacology

study of psychoactive drugs

Motion Parallax

if we move, nearby objects appear to move faster than objects further away

Ocular accommodation

ability of lens to change shape and lend light rays so objects are in focus