Visual Attention - chapter six

attention

attention

focusing on specific objects while ignoring others; brings objects into view and enhances processing, resulting in enhanced perception—important because perceptual system has a limited capacity for processing (prevents overload)

two main reasons for paying attention to some things but not others

enhanced processing → enhanced perception
prevents overload (if overloaded then you won’t process anything particularly well)

visual scanning

looking from one place to another—necessary because only one place on the retina (fovea) creates a good detail vision, including fixation

fixation

brief pause, focus on object

regions that differ from surroundings have ____, which attracts attention

visual saliency (color, contrast, movement, orientation, intensity)

involuntary attention

stimuli that stand our capture attention

voluntary attention

attention guided by goals and intentions

determinants of attention: cognitive factors

scene schemas
observer interests and goals
task-related knowledge

scene schema

people look longer at things that seem out of place
attention affected by knowledge of what is usually found in scene, knowledge about where things usually are in scenes helps guide attention through each scene

patterns of eye movements depended on _____

the task given to the subjects

task-related knowledge

where do people look when carrying out tasks (actions)?
tasks require attention to different places at different steps
eye movement is determined primarily by task—eye movements occur just before the information is needed

effects of attention on responding

behavioral response
perceptual response (perception)
physiological response

attention and behavioral response

“precueing” method—does presenting a cue that indicates where a stimulus will appear enhance the behavioral response to that stimulus

attention and perceptual response

does attention affect perception of an object’s appearance? need an experimental design that measures perceptual response rather than speed of responding

attention and physiological response

does attention increase brain activity? how does attention relate to activity in specific areas, if any?

binding

process in which visual features are combined to create our perception of a coherent object

the binding problem

how do an object’s feature become bound together? (feature integration theory)

feature integration theory

object → preattentive stage (features separated) → focused attention stage (features combined) → perception

preattentive stage

before focusing attention on something, features of the object are analyzed independently in different areas of the brain

focused attention stage

where they say binding occurs

illusory conjunctions

combining features of the different stimuli
“small green triangle” or “small red circle”
can be overcome with top-down processing

inattentional blindness

unaware of clearly visible stimuli if not directing attention/focus to them—missing things in our visual field (ex: the monkey business illusion, color changing card trick)

change blindness

difficulty detecting changes in scenes (ex: the door study, the switcharoo, continuity errors in film and television)

inattentional/change blindness most likely to occur when the changes are…

mundane, irrelevant objects

inattention/change blindness less likely to occur when the changes are

meaningful (ex: smokers when lighter moves)
surprising/odd (ex: printer in kitchen)
important to tasks and goals (ex: noticing change in color, but not height; in block-sorting computer task)

load theory of attention

low load allows for lots of capacity left for processing other stimuli that may be present; high load demands your full attention so little to no resources remain to process other stimuli

distracted driving

driving demands constant attention
texting while driving—takes one or both hands away, shift eyes from road to phone
talking on the phone while driving—fewer mental resources available for driving
just because the technology doesn’t take your eyes of the road, doesn’t mean its safe to use while the vehicle is moving