8 perception Flashcards
attention
the process of focusing on specific stimuli or aspects of the sensory environment whilst ignoring and therefore excluding others
sustained attention
maintenance of attention on a specific stimulus or task for a continuous period of time without being distracted
divided attention
the ability to distribute attention so that two or more activities may be performed simultaneously
selective attention
choosing and attending to a specific stimulus whilst at the same time excluding other stimuli
top-down processing
a perceptual process that starts ‘at the top’ with higher level ‘cognitive processing’ in the brain and then works ‘down’ from the whole to the details
- prior knowledge
bottom-up processing
the perceptual process starts ‘at the bottom’ with raw sensory information that is sent ‘up’ to the brain for higher-level mental ‘processing’
biological factors of visual perception (DDBM)
Depth perception: the ability to accurately estimate the distance of objects and therefore perceive the world in three dimensions
Depth cues: a source of info. from the environment (external cue) or from within the body (internal cue) that aids perception of how far away objects are and therefore depth perception
- Binocular depth cues: using both eyes to work together to provide information to the brain about depth and distance
- Monocular depth cues: using only one eye to provide information to the brain about depth and distance
Binocular depth cues (CR)
- Convergence: involves the inward turning of the eyes to focus on nearby objects
- Retinal disparity: based on the difference (disparity) of the two retinal images
Monocular depth cues (AP)
- Accommodation: automatic adjustment of the shape of the lens to focus on an object in response to changes in how far away the object is
- the monitoring of the cilliary muscles; relax = far away, contract = close
- Pictorial depth cues
Pictorial depth cues (LIRTH)
- Linear perspective: apparent convergence of actual or imagined parallel lines as they recede into the distance
- Interposition: the principle that an object which partially covers another is closer than the object it covers and the covered object is further away; overlap
- Texture gradient: the extent to which fine detail can be perceived in a surface
- Relative size: perceptual tendency to visually perceive the object that produces the largest image on the retina as being closer and vice versa
- Height in the visual field: perceptual tendency to visually perceive objects located closer to the horizon as being more distant than objects located further from the horizon
Psychological factors of visual perception (GP)
- Gestalt principles: organisation of the features of a visual stimulus by grouping them to perceive a whole, complete form
- Perceptual set: a temporary readiness to perceive something in accordance with expectations of what it is
Gestalt principles (SPCF)
Figure-ground: organising visual info by perceptually dividing a visual scene into a ‘figure’, which stands out from the ‘ground’ (surrounding)
Closure: perceptual tendency to mentally fill in or ignore gaps in a visual image and to perceive objects as complete
Similarity: tendency to perceive parts of a visual image that have similar features as belonging together in a group
Proximity: tendency to perceive parts of a visual image that are positioned close together as belonging together in a group; nearness
Perceptual set (CEMP)
Context: the setting, situation or environment in which an event occurs
Motivation: processes within an organism that activate behaviour directed towards achieving a particular goal
Past experience: personal experiences throughout an individual’s life
- Memory: the process of storing and retrieving this perceived information for use when needed
Emotional State
Social factors of visual perception
Culture - experience with or in a particular culture can influence the way we process and interpret visual information
Difference between convergence and accommodation
Convergence involves the inward movement of the eyes to maintain binocular vision, while accommodation involves the adjustment of the lens shape to focus on objects at different distances to maintain monocular vision.
