Visual Perception Flashcards
Spatial neglect
Spatial neglect (or hemisphere neglect) is a condition involving the inability to attend to sensory stimuli on one side of the body.
- individuals with this condition are unable to attend to one side of their body or perceive visual stimuli in one side of their visual field
- right hemisphere damage (can’t visually perceive the left side of their visual field), left hemisphere damage (can’t visually perceive the right side of their visual field)
Top down processing
Top down processing uses past experiences to perceive information.
Example: if someone has had a prior positive experience with a certain restaurant, they will use their past experience and expect another positive experience, when going back to that restaurant.
Top-Down processing
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Drawing on past experiences and knowledge to interpret sensation
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interpreting information according to expectations
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A perception is formed
Bottom-Up processing
What am I processing is using our senses to perceive new information and form a perception.
Example:
Bottom-up processing
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Analysing the specific features or elements of a stimulus.
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Creating a whole picture from the individual elements.
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A perception is formed
Attention
The level of awareness directed towards certain stimuli to the exclusion of others.
Sustained attention
Sustained attention: the maintenance of a high degree of attention over a prolonged period.
Example: you use sustained attention when focusing on new material to be learned
Type of cognitive processing required: controlled cognitive processing.
Mental effort required: a high level of mental effort required.
focus of attention: stimuli with some unpredictability.
best suited for: contexts in which new stimuli are likely to be encountered.
type of task focused on: Can be used for simple and complex tasks.
potential for misperceptions: the risk of misperception increases
- the longer you try to pay sustained attention
- the more difficult it is to pay attention
Selective attention
Selective attention refers to focusing on a single activity while disregarding other environmental stimuli.
Example: You use selective attention while learning a complex skill such as dribbling a football and focusing on a conversation in a noisy environment.
Type of cognitive processing required: controlled cognitive processing.
Mental effort required: a lot of mental effort required.
focus of attention: limited range of silent stimuli.
best suited for: focusing on particular stimuli and blocking out others.
type of task focused on: complex tasks.
potential for misperceptions: the risk of misperception is reduced because target stimuli are known.
Divided Attention
Divided attention: distributing attention to allow the processing of two or more stimuli at the same time.
Example: having learned balls skills and made them an automatic cognitive process, a footballer can also watch the motions of the other players and decide when and where to pass the ball, diving their attention between ball control and tactics.
- A circus performer divides their attention between riding a unicycle and juggling.
Type of cognitive processing required: automatic cognitive processing.
Mental effort required: little mental effort required.
focus of attention: multiple stimuli across tasks.
best suited for: multitasking and switching between tasks.
type of task focused on: simple tasks.
potential for misperceptions: performance decreases if one or more of the tasks focused on are complex.
Biopsychosocial model
An interdisciplinary model that looks at the interconnection between biology, psychology and social factors that influence a persons perception.
Applying the biopsychosocial model to visuals perception - biological factors
Depth perception: the ability to judge distances and see the world in 3D
Retinal disparity:
Depth perception
Depth perception: the ability to judge distances and see the world in 3D
Binocular depth cues - what are the 2 main binocular depth cues?
Binocular depth cues Required the use of both eyes to send information to the brain to perceive depth.
Convergence
Retinal disparity
Convergence
Convergence is a biology depth cue that involves the inward turning of the eyes, which the brain interprets as tension changes in the muscles around the eye.
The further away an object, the less inward turning of the eyes and the less muscle tension.
Only works if the object is within 7 metres.
Retinal disparity
Retinal disparity refers to the brain detecting similarities and differences between the information being sent from each eye, due to the eyes being 6-7 cm apart.
When the disparity, or differences, between the image is greatest, the object is perceived as close to the observer. Less disparity between the two images indicated that the object is further away
Monocular depth cues
Monocular depth cues require only one to send information to the brain to perceive depth.
Accomodation
Accomodation
The ability of the eye to change focus from near to distant objects and back again.
The brain detects movement in the muscles of the eye as it changes the shape of the lens to focus on nearby or distant objects.
