Attention and Scene Perception

Question 1

inattentional blindness

Answer 1

A failure to notice—or at least to report—a stimulus that would be easily reportable if it were attended.

Question 2

scene-based guidance

Answer 2

Information in our understanding of scenes that helps us find specific objects in scenes (e.g., objects do not float in air, faucets are near sinks).

Question 3

response enhancement

Answer 3

An effect of attention on the response of a neuron in which the neuron responding to an attended stimulus gives a bigger response.

Question 4

neglect

Answer 4

As a neurological symptom, (1) in visual attention the inability to attend to or respond to stimuli in the contralesional visual field (typically, the left field after right parietal damage); (2) ignoring half of the body or half of an object.

Question 4

serial self-terminating search

Answer 4

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

Question 4

set size

Answer 4

The number of items in a visual display.

Question 5

preattentive stage

Answer 5

The processing of a stimulus that occurs before selective attention is deployed to that stimulus.

Question 6

conjunction search

Answer 6

Search for a target defined by the presence of two or more attributes (e.g., a red, vertical target among red horizontal and blue vertical distractors).

Question 6

target

Answer 6

The goal of a visual search.

Question 7

attentional blink

Answer 7

The tendency not to perceive or respond to the second of two different target stimuli amid a rapid stream of distracting stimuli if the observer has responded to the first target stimulus within 200–500 milliseconds before the second stimulus is presented.

Question 7

guided search

Answer 7

Search in which attention can be restricted to a subset of possible items on the basis of information about the target item’s basic features (e.g., its color).

Question 8

sharper tuning

Answer 8

An effect of attention on the response of a neuron in which the neuron responding to an attended stimulus responds more precisely. For example, a neuron that responds to lines with orientations from –20 degrees to +20 degrees might come to respond to ±10-degree lines.

Question 8

simultagnosia

Answer 8

An inability to perceive more than one object at a time. Simultagnosia is a consequence of bilateral damage to the parietal lobes (Balint syndrome).

Question 9

proto-object

Answer 9

A loose collection of unbound features (size, color, and so forth) that will be a recognizable object, once attended.

Question 10

reaction time (RT)

Answer 10

A measure of the time from the onset of a stimulus to a response.

Question 11

selective attention

Answer 11

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

Question 13

distractor

Answer 13

In visual search, any stimulus other than the target.

Question 13

parietal lobe

Answer 13

In each cerebral hemisphere, a lobe that lies toward the top of the brain between the frontal and occipital lobes.

Question 14

ensemble statistics

Answer 14

The average of and distribution of properties like orientation or color over a set of objects or over a region in a scene.

Question 15

extinction

Answer 15

In visual attention, the inability to perceive a stimulus to one side of the point of fixation (e.g., to the right) in the presence of another stimulus, typically in a comparable position in the other visual field (e.g., on the left side).

Question 17

parahippocampal place area (PPA)

Answer 17

A region of extrastriate visual cortex in humans that is specifically and reliably activated more by images of places than by other stimuli.

Question 18

salience

Answer 18

The vividness of a stimulus relative to its neighbors.

Question 19

fusiform face area (FFA)

Answer 19

A region of extrastriate visual cortex in humans that is specifically and reliably activated by human faces.

Question 20

ipsilesional field

Answer 20

The visual field on the same side as a brain lesion.

Question 22

illusory conjunction

Answer 22

An erroneous combination of two features in a visual scene—for example, seeing a red X when the display contains red letters and Xs but no red Xs.

Question 23

binding problem

Answer 23

The challenge of tying different attributes of visual stimuli (e.g., color, orientation, motion), which are handled by different brain circuits, to the appropriate object so that we perceive a unified object (e.g., red, vertical, moving right).

Question 24

stimulus onset asynchrony (SOA)

Answer 24

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

Question 26

cue

Answer 26

A stimulus that might indicate where (or what) a subsequent stimulus will be. Cues can be valid (giving correct information), invalid (incorrect), or neutral (uninformative).

Question 27

spatial layout

Answer 27

The description of the structure of a scene (e.g., enclosed, open, rough, smooth) without reference to the identity of specific objects in the scene.

Question 28

visual-field defect

Answer 28

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

Question 29

visual search

Answer 29

Search for a target in a display containing distracting elements.

Question 31

change blindness

Answer 31

The failure to notice a change between two scenes. If the gist, or meaning, of the scene is not altered, quite large changes can pass unnoticed.

Question 33

parallel search

Answer 33

A search in which multiple stimuli are processed at the same time.

Question 34

feature search

Answer 34

Search for a target defined by a single attribute, such as a salient color or orientation.

Question 35

feature integration theory

Answer 35

Anne Treisman’s theory of visual attention, which holds that a limited set of basic features can be processed in parallel preattentively, but that other properties, including the correct binding of features to objects, require attention.

Question 36

repetition blindness

Answer 36

A failure to detect the second occurrence of an identical letter, word, or picture in a rapidly presented stream of stimuli when the second occurrence falls within 200–500 milliseconds of the first.

Question 37

contralesional field

Answer 37

The visual field on the side opposite a brain lesion. For example, points to the left of fixation are contralesional to damage in the right hemisphere of the brain.

Question 38

rapid serial visual presentation (RSVP)

Answer 38

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

Question 39

attention

Answer 39

Any of the very large set of selective processes in the brain. To deal with the impossibility of handling all inputs at once, the nervous system has evolved mechanisms that are able to restrict processing to a subset of things, places, ideas, or moments in time.