PSYCHOLOGY UNIT 1 CHAPTER 03- The Visual Perception System Flashcards
❓❓❓What is a ‘sensation’?
-the process by which our sense organs and receptors detect and respond to sensory information that simulates them
❓❓❓What is a ‘perceptual set’?
-the predisposition (readiness) to perceive something in accordance with what we expect it to be
❓❓❓What is perception?
-refers to the process by which we give meaning to sensory information, resulting in our personal interpretation of that information.
☀️☀️☀️the visual perception system includes parts of the eye, optic nerve, brain and nervous system
❓❓❓What is the Cornea?
- a covering which protects the eye and helps to focus light rays onto the retina at the back of the eye
❓❓❓What is the pupil?
-an opening in the iris that helps to control the amount of light entering the eye
❓❓❓What is the lens?
-a transparent, flexible, convex structure located behind the pupil that focuses light onto the retina
❓❓❓What does the Retina do?
-receives and absorbs light and processes images
❓❓❓What are the four Gestalt Principles?
- figure-ground
- closure
- proximity
- similarity
❓❓❓What is figure-ground (Gestalt)?
-separating an object from the background
❓❓❓What is closure (Gestalt)?
-the process of mentally completing a visually incomplete object by subjectively filling in gaps to perceive a whole form
❓❓❓What is proximity (Gestalt)?
-the idea that someone is more likely to group things if they are closer together
❓❓❓What is similarity (Gestalt)?
- the idea that someone is more likely to perceive things that are similar as a whole form
- ‘grouping similar things in a column’
❓❓❓What are the three depth cues?
- monocular cues
- binocular cues
- pictorial cues
❓❓❓What are the two binocular cues?
- convergence
- retinal disparity
❓❓❓What is the monocular cue?
-accommodation
❓❓❓What are the five pictorial cues?
- linear perspective
- interposition
- height in the visual field
- relative size
- texture gradient
❓❓❓What is convergence (binocular)?
- when the brain detects and interprets depth from changes in tension in eye muscles, when the eyes turn inward to focus in close objects
- the further away an object is, the less tension in the eye
❓❓❓What is retinal disparity (binocular)?
-the small difference between an image from your right and left eye
❓❓❓What is accommodation (monocular)?
-when the muscles attached to the lens in each eye alter the shape of the lens to enable the eye to focus on nearby objects
Near= bulges Far= elongates (flattens)
❓❓❓What is linear perspective (pictorial)?
-the APPARENT convergence of parallel lines creates the impression of increasing distance e.g a road
❓❓❓What is interposition (pictorial)?
-an object that partially blocks another object from view is perceived to be in front of, and therefore close than, the object it overlaps
❓❓❓What is height in the visual field (pictorial)?
-objects closer to the horizon appear more distant than those further from the horizon
❓❓❓What is relative size (pictorial)?
-when 2 objects are known to be of similar size, the one projecting a smaller retinal image is perceived to be further away
❓❓❓What is texture gradient (pictorial)?
-surface features become smaller and less detailed the more distant an object becomes
❓❓❓What are the three consistencies?
- brightness
- shape
- size
❓❓❓What five things can affect perceptual set?
- cultural factors
- past experience
- emotional state
- motivation
- context
❓❓❓What are the four characteristics of the visual perception system?
- Reception
- Transduction
- Transmission
- Organisation and interpretation
❓❓❓What is reception (characteristics)?
-Photoreceptors in the retina detect and receive light
❓❓❓What is transduction (characteristics)?
-the light is converted from electromagnetic to electrochemical energy
❓❓❓What is transmission (characteristics)?
-the information is sent to the brain via the optic nerve
❓❓❓What is organisation and interpretation (characteristics)?
-When visual information reaches the brain it is organised and interpreted so that it is meaningful and can be understood
❓❓❓What is depth perception?
-the ability to decode information within 2 dimensional retinal images to gain a 3-D impression of the environment including an idea of how far away objects are spatially located
❓❓❓What are depth cues?
-physiological or environmental indications that help us to establish a perception and/or distance
❓❓❓Monocular depth cues allow________
Binocular depth cues require______
- the judgment of distance and depth using 1 eye
- require combined use of 2 eyes
❓❓❓What is size consistency?
-the perceived size of object remains constant despite changes in the size of the image it casts on the retina (e.g. Someone walking towards you)
❓❓❓What is shape consistency?
-the perceptual constancy whereby an object’ perceived shape is not affected but the changing shape of its image on the retina (e.g. Looking at a door from an angle makes it look like a trapezoid but we know it is actually still a rectangle)
❓❓❓What is brightness consistency?
-an object appears to maintain the same level of brightness relative to its surroundings, despite variations in the amount of light reflected from it onto the retina. (E.g. Shadow on a flower- we still know the colour is yellow, despite the dark spot)
❓❓❓What is orientation consistency?
-the ability to perceive the actual placement or orientation of objects in the world despite their arrangement or alignment in the retinal image
❓❓❓What is ‘bottom-up’ processing (perceptual set)?
-analysing sensory information, starting with low-level features (lines, shape, edges, colour) and building upwards to complete picture
❓❓❓What is ‘top-down’ processing (perceptual set)?
-applying pre existing or high-level knowledge so as to rapidly organise sensory information into meaningful perception
❓❓❓What is context (effects perceptual set)?
- information that surrounds a stimulus and contributes to perceptual set
- also the setting in which a perceived stimulus occurs
(e.g. A basketball player will look average on court but tall on the street with others)
❓❓❓What is last experience (effects perceptual set)?
- prior exposure to stimuli which contributes to perceptual set
- refers to personal experiences of each individual and shapes the way we perceive things
❓❓❓What is a visual illusion?
-a misinterpretation (distortion or mistake) of real sensory information
☀️☀️☀️in an illusion, length, position, motion or direction is consistently misjudged
-different from hallucinations as they are imaginary
❓❓❓What did Toch and Schulte conclude in their experiment (police training)?
- they concluded that the more police training the participants had completed, the more likely it was for them to perceive an image as violent
- SHOWS PAST EXPERIENCE*
❓❓❓What did Bruner and Minturn conclude in their experiment (B/13 stimulus)?
They concluded that if the participant was exposed to a series of letters before viewing the B/13 stimulus, they were more likely to perceive it as a ‘B’, however if they were exposed to a series of numbers they were more likely to perceive a 13
SHOWS CONTEXT
❓❓❓What is the ‘apparent-distance hypothesis’?
An apparently distant object within the same sized retinal image as an apparently nearer object will be perceived as the larger of the two
❓❓❓What is the muller-lyer illusion?
-where two lines of equal length (one capped with inward pointing arrowheads, the other capped with outward pointing arrowheads) appear to be different lengths
❓❓❓What is the socio-cultural perspective of the muller-lyer illusion?
-people who live in ‘non-carpentered’ worlds will perceive the lines as two dimensional
☀️☀️☀️the Zulus Tribe live in remote ares of Africa in circular houses With no corners or edges- they will be more likely to perceive the images as equal length
-people in urban areas are more likely to perceive the illusion due to their past experience of buildings
❓❓❓What is the biological perspective on the muller-lyer illusion?
-the entire feather-tailed line in the illusion is longer because it lengthens the eye movement required to view the line, there we perceive the line as being longer (later disproved)
❓❓❓What is the cognitive perspective on the muller-lyer illusion?
-results from inappropriate use of perceptual processes involved in maintaining size consistency therefore outward pointing arrowhead line is perceived as the longer retinal image
❓❓❓What is the behavioural perspective on the muller-lyer?
- it has been proposed that we experience the illusion as it contradicts with what we have learned in everyday life through physical reality
e. g. Architectural features
❓❓❓What is the Ames Room?
- an intentionally distorted room that interrupts perceptual consistencies so as to create the the illusion that people change size as they cross the floor from one corner of the room to another
- trapezoid room that appears to be rectangular
- has a peephole to view the roo
❓❓❓What are photoreceptors?
-lights sensitive cells in the retina
☀️☀️☀️PHOTORECEPTORS
- 2 kinds: rods and cones
- both are parts of the retina but in different areas
- no photoreceptors in the blind spot (where the optic nerve leaves the eyes)
❓❓❓What are the main features of cones?
- mainly in fovea of retina
- work best in bright lights
- Central vision
- gives colour information
❓❓❓What are the main features of rods?
- in periphery of retina
- operate best In dim light
- rough outline of objects in periphery vision
- no colour information
❓❓❓Visual perception principles influence…
… How visual stimuli are organised so that they can be interpreted meaningfully
