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Vision - Coggle Diagram
Vision
Visual coding
depedent on how far light travels before it strkes one's eye
Colour Vision
Trichromatic theory
three wavelength related to three different cones
ratio of cones determines the colour
Opponent-Process theory
persive color in paired opposites
Retinex theory
compares information of the retina to determine colour and brightness
electromagnectic spectrum
deficiency
impairment in perceiving colour
colour constancy
ability to recognize the same colour in different lighting.
structure responsible for vision
Amacrine Cells
Controls ability of ganglion cells reponds to specific aspects of visual stimuli
Bipolar cells
sends mesage to ganglion cells, Axons joined to form optic nerve
optic nerve
Blind spot
Fovea
for acute and detailed vision
Midget Ganglion cell
one bipolar + one ganglion
Periphery of Retina
less detailed vision, more perception of faint light
Visual receptors
Adaptive
Rods
Photopigments
Cones
System
Optic Chiasm
blind spot
Vertebrate Retina
Path
Lateral Geniculate
specialized for visual perception
inhibition
sharpens contrast
reduce activity when neighboring activates
Receptive fields
either excites or inhibits a cell
Parvocellular Neurons
located around fovea
highly sensitive to colour and detail
Magnocellular Neurons
throughout the retina
sensitive to large overall and moving stimuli
Koniocellular Neurons
throughout retina
sensitive to short-wavelength sensitive cone cells
damage shows blind sight
Visual Cortex
Primary visual Cortex
receives information from the lateral geniculate nucleus
columnar organization
respond to either side of the eye or both eye
cells
feature detectors
prolonged exposure decrease sensitivity
development
lack of stimulation
one eye - unresponsive
both eye - sluggish response
critical period
parallel processing
secondary visual cortex
receives information from primary
ventral and dorsal stream
ventral goes through temporal cortex
dorsal goes through parietal cortex
Cells
simple cells
more light = more respond
fixed excitatory and inhibitory zones
complex cells
large receptive field
respond strongly to moving stimulus
hypercomplex cells
strong inhibitory area
Stereoscopic Depth Perception
perceiving distance
strabismus
stereoscopic depth is impaired
Early exposure
becoming responsive to only one pattern
astigmatism
difficulty in recognizing objects
analysis of shape
agnosia
inability to recognize object
prosopagnosia
inability to recognize faces
motion
middle temporal cortex respond to stimulus moving
medial superior temporal cortex respond to details of moving stimulus
receives imput from magnocellular path
motion blindness
inability to determine direction, speed or whether objects are moving
mostly cause by damage in middle temporal cortex
saccades
decrease in the activity of visual cortex during eye movement