Chapter 2 Flashcards
Retinal ganglion cells
Retinal cells that give the output of the retina
Retinopy
The notion that there is mapping between the receptor cells in the retina and points in the surface of the visual cortex
Receptive field
The region in which light influences the activity of a particular neuron.
Lateral inhibition
Reduction of activity in one neuron caused by activity in a neighboring neuron
Achromatopsia
A condition caused by brain damage in which there is very limited color perception but form and motion perception are intact
Akinetopsia
A brain-damaged condition in which morion lerception is damaged, but still perception is decent.
Ventral stream
The part of the visual processing system involved in objects perception a d recognition and the formationif perceptual representations.
Dorsal stream
The partnof the visual processing system most involved in visually guided action
Allocentric stream
Visual or spacial coding of objects relative to each other
Egocentric coding
Visual or spatial coding dependent on the position of the observers body
Optic ataxia
A condition in which there are problems making visually guided movements in spite if reasonably intact visual perception
Visual form agnosia
A condition in which there are severe problems in shape perception
Hollow face illusion
A concave face masj is perceived as normal from far away
Proprioception
An individual’s awareness if the position and orientation of parts of their body
Dichromacy
A deficiency in color vision where one color is missing
Negative Afterimages
The illusory perception of the complementary colour to the one that has just been ixated; green is the complementary colour to red and blue is complementary to yellow.
Color constancy
Colour constancy The tendency for an object to be perceived as having the same colour under widely varying viewing conditions.
Illuminant
A source of light illuminating a surface or object.
Mutual illumination
The light relected from the surface of an object impinges on the surface of a second object.
Chromatic adaptation
Changes in thr visual sensitivity to color stimuli when illumination alters
Monocular cues
Cues to depth that can be used by one eye but can also be used by both eyes together.
Binocular cues
Cues to depth that require both eyes to be used together.
Oculomotor cues
Cues to depth produced by muscular contractions of the muscles around the eye; use of such cues involves kinaesthesia (also known as the muscle sense).
Texture gradient
The rate of change of texture density from the
front to the back of a slanting object.
Motion parallax
Depth cue based on movement in one part of the retinal image relative to another
Binocular disparity
A depth cue based on the slight disparity in the two retinal images when an observer views a scene; it is the basis for stereopsis.
Stereopsis
Depth perception based on the small discrepancy in the two retinal images when a visual scene is observed (binocular disparity).
Autostereogram
A complex two- dimensional image perceived as three- dimensional when not focused on for a period of time.
Amblyopia
A condition in which one eye sends an inadequate input to the visual cortex; colloquially known as lazyeye.
Vergence
cue to depth based on the inward focus of the eyes with close objects.
Accomidation
depth cue based on changes in optical power produced by thickening of the eye’s lens when an observer focuses on close objects.
Haptic
Sense of touch
Size constancy
Objects are perceived to have a given size regardless of the size of the retinal image.
Ames room
A very distorted room that nevertheless looks normal under certain viewing conditions.
Honi phenomenon
The typical apparent size changes when an individual walks along the rear wall of the Ames room are reduced when female observers view a man to whom they are very close emotionally.
Open-object illusuion
The misperception that objects with missing boundaries are larger than objects the same size without missing boundaries.
Body size effect
An illusion in which misperception of one’s own bodily size causes the perceived size of objects to be misjudged.
Subliminal perception
Perceptual processing occurring below the level of conscious awareness that can nevertheless inluence behaviour.
Blindsight
The ability to respond appropriately to visual stimuli in the absence of concious visual experience in patients with damage ti the primary visual cortex
