Unit 2 AOS 2 Flashcards
visual perception
Visual perception occurs through the interaction of numerous
factors, many of which automatically influence assist our
interpretation of what we are looking at.
biological factor of visual perception
Visual perception starts at the eye where light is received, converted
into neural signals then sent to the brain for interpretation.
All of the anatomical structures and processes of the eye and brain,
neural pathways that connect them and the genetics that underlie and
shape their maturation and development over time, are just some of the
biological factors that can influence visual perception
depth cues
to locate objects in a space. Without this ability, we would find it difficult to navigate and
interact with our world. In order to locate objects in space, we need to judge
whether one object is above, below, or to the left or right of another. We also
need to judge how far away objects are from each other and ourselves.
binocular depth cues
Those that require the use of both eyes working together in
order to provide information to the brain about depth and
distance.
Important in determining the distance of objects that are close.
2 types
- Retinal disparity
- Convergence
convergence
Convergence involves the brain detecting and interpreting depth
or distance from changes in tension in the eye muscles that occur
when the two eyes turn inwards to focus on objects that are
close.
The brain interprets greater tension in the eye muscles as an
object gets closer and less tension as an object gets further
away.
retinal disparity
Retinal disparity refers to the very slight difference (‘disparity’) in the location of
the images on the retinas (due to their slightly different angles of view), which
enables us to make judgments about the depth or distance of an object.
When the two different retinal images are combined in the brain, the images received
from each eye are compared. Any disparity or difference between the two images
provides information about the depth of the object or its distance from the
viewer.
monocular depth cues
- require the use of only one eye to provide information to the brain about depth and distance, but they also operate with both eyes
Many monocular cues are referred to as pictorial cues because artists use
them to create depth and distance on two-dimensional surfaces such as paper
and canvas.
accommodation
-the automatic adjustment of the shape of the eye lens
to focus an object in response to changes in how far away the object is.
-The brain monitors the movement of the ciliary muscles that control the
shape of the lens. These muscles contract to enable the bulging of the lens,
and expand to allow it to elongate (flatten)
pictorial depth cues
Linear Perspective
Interposition
Texture gradient
Relative size
Height in the visual field
linear perspective
Linear perspective is the apparent convergence of actual or imagined parallel
lines as they recede (‘go back’) into the distance
interposition
also called overlap, occurs when one object partially blocks/ covers another, and the partially blocked object is perceived as further away than the object that obscures it (and vice versa).
texture gradient
refers to the gradual reduction of the detail that occurs in an object or surface as it recedes into the distance, compared with an object
or surface that is close and perceived in fine detail
relative size
refers to the tendency to visually perceive the object that
produces the largest image on the retina as being closer, and the object that
produces the smallest image on the retina as being further away.
However, the objects being perceived must be expected to be about the same size
in real life.
height in the visual field
refers to the location of objects in our field of
vision, whereby objects that are located closer to the horizon are perceived
as being more distant than objects located further from the horizon
Psychological factors
involve the many and varied mental processes and
influences on visual perception. These are sourced within the individual and
therefore significantly influence top-down processing of incoming sensory
information.
gestalt principles
In relation to visual perception, Gestalt principles refers to ways in
which we organise the features of a visual stimulus by grouping them to perceive a whole, complete form. The ‘principles’ are like ‘rules’ that we apply
to visual information to assist our perceptions.
We tend to automatically use these Gestalt principles, without any conscious
effort or awareness that we are doing so
4 main gestalt principles
Figure-ground
Closure
Similarity
Proximity
figure ground and example
perceptual set
temporary readiness to perceive something in accordance with what we expect it to be
context
setting or environment in which perception is made
B/13 experiment
Bruner and Minturn investigated the effect of context on peoples perception of a visual stimulus. Participants were either shown a series of a letters or numbers however within each series was an ambiguous figure
motivation
internal processes within us which activate behavior’s that we direct towards achieving a particular goal
- can be influenced by psychological factors such as interests
past experience
refers to our personal experience throughout our lives
memory
storing and retrieving this perceived info for use when needed
