Week 11: Attention and Scene Perception Definitions

attention

any of the very large set of selective processes in the brain

selective attention

the form of attention involved when processing is restricted to a subset of the possible stimuli

external

attending to stimuli in the world

internal

attending to one line of thought over another or selecting one response over another

overt orienting

directing a sense organ toward a stimulus, like turning your eyes or head

covert orienting

attending without giving an outward sign you are doing so

divided

splitting attention between two different stimuli

sustained

continuously monitoring some stimulus

automatic reflexive orienting

unpredictable occurrences automatically capture our attention

volitional orienting

directing attention due to the goals and intentions of an individual

stimulus onset synchrony

the time between the onset of one stimulus and the onset of another

exogenous cue

automatically grabs and directs attention

endogenous cue

takes about 100 ms to figure/interpret things

object-based attention

attention selects particular objects or portions of objects, rather than just a single location

inhibition of return (IOR)

the relative difficulty in getting attention (or the eyes) to move back to a recently attended or fixated location

visual search

looking for a target in a display containing distracting elements

set size

the number of items in a visual search display

search efficiency

the average increase in RT for each distractor item added to the display

feature search

searching for a target defined by a single attribute, such as a salient colour or orientation

parallel

in visual attention, referring to the same processing of multiple stimuli at the same time

conjunction search

search for a target defined by the co-occurrence of two or more features

serial self-terminating search

a search from item to item, ending when a target is found

the binding problem

the challenge of tying different attributes of visual stimuli, which are handled by different brain circuits, to the appropriate object so we perceive a unified object

feature integration theory

triesman’s theory of visual attention, which holds that a limited set of basic features can be processed in parallel pre-attentively, but that other properties, including the correct binding of features to objects, require attention

illusory conjunction

an erroneous combination of features in a visual scene

guided search

attention is restricted to a subset of possible items based on information about the item’s basic features (e.g., colour or shape)

scene-based guidance

information in our understanding of scenes that helps us find specific objects in scenes

anchor objects

relatively big object that provides info about the location of other objects

scene grammar

set of implicit rules about what can be where that allow you to understand a scene

rapid serial visual presentation (RSVP)

an experimental procedure in which stimuli appear in a stream at one location (typically the point of fixation) at a rapid rate (typically about ten per second)

attentional blink

the difficulty in perceiving and responding to the second of two target stimuli amid a RSVP stream of distracting stimuli

repetition blindness

the failure to recognize a second occurrence of a visual display

spotlight model

attention is restricted in a space and moves from one point to the next. Areas within the spotlight receive extra processing

zoom lens model

the attended region can grow or shrink depending on the size of the area to be processed

inattentional blindness

a failure to notice a fully-visible but unexpected object or event because attention is focused elsewhere

change blindness

the failure to notice a change between two scenes

visual field defect

a portion of the visual field with no vision or with abnormal vision, typically resulting from damage to the visual nervous system

unilateral visual neglect

a condition in which a person has difficulty attending to stimuli in one half of the visual field

extinction

in visual attention, the inability to perceive a stimulus to one side of the point of fixation in the presence of another stimulus, typically in the other visual field

blindsight

the ability to point to and sometimes discriminate visual stimuli without any conscious awareness of them