Chapter 7- Attention and Scene Perception Flashcards
Attention
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 bias processing to a subset of thing, places, ideas, or moments in time.
Selective Attention
The form of attention involved when processing is restricted to a subset of the possible stimuli.
Reaction Time (RT)
A measure of the time from the onset of a stimulus to a response.
Cue
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).
Exogenous Cue
In directing attention, a cue that is located out (exo) at the desired final location of attention.
Endogenous Cue
In directing attention, a cue that is located in (endo) or near the current location of attention.
Stimulus Onset Asynchrony (SOA)
The time between the onset of one stimulus and the onset of another.
Inhibition of Return
The relative difficulty in getting attention (or the eyes) to move back to a recently attended (or fixated) location.
Visual Search
A search for a target in a display containing distracting elements.
Target
The goal of a visual search.
Distractor
In a visual search, any stimulus other than the target.
Set Size
The number of items in a visual display.
Feature Search
Visual search for a target defined by a single attribute, such as a salient color or orientation.
Salience
The vividness of a stimulus relative to its neighbors.
Parallel Search
Visual search in which multiple stimuli are processed at the same time.
Serial Self-Terminating Search
A search from item to item, ending when a target is found.
Guided Search
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).
Conjunction Search
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).
Prime
A stimulus that might make it easier or faster to respond to a subsequent stimulus. If you are primed by the word “cat”, you will respond more quickly to the word “mouse” than to “broom” or some other unrelated word.
Scene-Based Guidance
Information in our understanding of scenes that helps us find specific objects in scenes (e.g., objects do not float in air, faucets are found near sinks).
Anchor Objects
Typically a relatively big object that provides information about the location of other objects. For instance, the toilet provides information about the location of the toilet paper.
Binding Problem
The challenge of trying 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).
Feature Integration Theory
Anne Treisman’s theory of visual attention, which holds that a limited set of basic features can be processed in parallel pre-attentively, but other properties, including the correct binding of features to objects, require attention.
Preattentive Stage
The processing of a stimulus that occurs before selective attention is deployed to that stimulus.
Illusory Conjunction
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 non red Xs.
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 8 per second).
Attentional Blink (AB)
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 200-500 milliseconds before the second stimulus is presented.
Priority Map
A hypothetical neural representation of visual space in which the activity at each point reflects how much that location (or object) will attract attention.
Lateral Interparietal Area (LIP)
A brain region, present in both parietal lobes that serves an important role in the control of visual attention.
Frontal Eye Fields (FEF)
Brain regions in both frontal lobes that help to coordinate visual selective attention with the movement of the eyes.
Superior Colliculus (SC)
A structure in the midbrain that is important in initiating and guiding eye movements.
Fusiform Face Area (FFA)
A region of extrastriate visual cortex in humans that is specifically and reliably activated by human faces.
Parahippocampal Place Area (PPA)
A region of extrastriate visual cortex in humans that is specifically and reliably activated more by images of places than by other stimuli.
Response Enhancement
An effect of attention on the response of a neuron in which the neuron responding to an attended stimulus gives a bigger response.
Sharper Tuning
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 liens with orientations from -20 degrees to +20 degrees might come to respond to +/- 10-degree lines.
Altered Tuning
An effect of attention on the response of a neuron in which the neuron responding differently to the features of an attended versus an unattended stimulus. For example, a neuron that responds strongly to lines with orientations from -20 degrees to +20 degrees might shift to respond strongly to -10 to +30 degree lines.
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.
Parietal Lobe
In each cerebral hemisphere, a lobe that lies toward the top of the brain between the frontal and occipital lobes.
Neglect
In reference to a neurological symptom, in visual attention: 1) The inability to attend 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.
Contralesional Field
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.
Extinction
In reference to 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).
Ipsilesional Field
The visual field on the same side as a brain lesion.
Attention Deficit Hyperactivity Disorder (ADHD)
A quite common childhood disorder that can continue into adulthood, symptoms of which include difficulty focusing attention and problems controlling behavior.
Balint Syndrome
A disorder where everything except the current object of attention seems to be blocked from conscious perception.
Reachspace
A region of visual space that is within arm’s reach: Bigger than most objects, smaller than a typical scene, and critically positioned where the arms can reach.
Peripersonal Space
That part of the world that is near your body- especially, your hands.
Ensemble Statistics
The average and distribution of properties like orientation or color over a set of objects or over a region in a scene.
Proto-Object
A term used to refer to objectlike stimuli before they are attended and recognized.
Spatial Layout
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.
Gist
The essential or primary character of a scene. In vision, gist typically refers to information that can be gleaned in a very brief glimpse, without voluntary eye movements.
Change Blindness
When on scene is replaced by another version of the same scene, observers may be unable to report what changed between the two versions.
Intentional Blindness
A failure to notice- or at least to report- a stimulus that would be easily reportable if it were attended.
