Attention Flashcards
Selective attention
Filter out irrelevant material to select the relevant
Executive control over attention / cognitive control
Control over processing when the response is not the automatic one or there are conflicting potential responses
Sustained attention
Maintaining processing on current goals over extended periods of time
Developmental disorder of attention?
ADHD
Degenerative disorders of attention?
PD and AD
Disorders of attention in young adults?
TBI, schizophrenia
What are the three disorders of attention following focal lesions?
Simultanagnosia, extinction and neglect
What are the two ways selective attention can act?
Can act ‘bottom up’ or ‘top down’
What is bottom up selective attention? (example)
Bottom up or stimulus-driven attention: Salient information in the environment captures brain processing
(abrupt changes in the visual scene, such as onset/offset of luminance or sudden movement of an object, capture attention rapidly because they might be important for survival)
What is top down selective attention? (example)
Top down or goal-directed attention: Processing is selectively directed towards certain information
(if you’re meeting a friend who’ll be wearing a red coat at a crowded station, you can selectively attend to red items, and filter out all non-red objects (distracters))
Three ways to measure selective attention?
Track where we look (gaze direction)
Show it is possible to enhance perception
Measure how long it takes to detect a target
What is free-viewing condition?
Where overt attention goes when no task
What is the cost of attending to one feature?
Reduced perception at other spatial locations (Helmholtz).
Is attention and looking the same?
No, we can pay attention covertly, i.e look at one object but attend to another
When is attention detection faster?
If attention is already deployed at the location a target is presented (Posner) or when there are fewer distracting stimuli (Treisman).
What brain regions are involved in shifting attention covertly and overtly?
Superior parietal lobe, intraparietal sulcus and frontal eye fields
(both hemispheres)
Balint syndrome?
Patient with large, bilateral parietal lesions. Leads to illusory conjunctions (when binding of specific features fail).
Simultanagnosia?
Inability of an individual to perceive more than a single object at a time, restricted spatial window of visual attention. Component of Balint’s.
What can cause simultanagnosia?
Ventral occipito-temporal lesions cause a mild form of the disorder, while dorsal occipito-parietal lesions cause a more severe form of the disorder
What is extinction?
Impairs the ability to perceive multiple stimuli of the same type simultaneously.
Limited attentional capacity and an attentional bias towards ipsilesional space
Where do patients with extinction show lack of awareness?
Lack of awareness in the contralesional side of space (towards the left side space following a right lesion), they are more likely to attend to and become aware of ipsilesional stimuli at the expense of contralesional ones
What can cause extinction?
Cortical lesion was almost always found in the right parietal angula gyrus region.
What is neglect?
Neglect is a neuropsychological condition in which, after damage to one hemisphere of the brain is sustained, a deficit in attention to and awareness of one side of the field of vision is observed.
What causes neglect?
Hemispatial neglect results most commonly from strokes and brain unilateral injury to the right cerebral hemisphere.
Neglect is often produced by massive strokes in the middle cerebral artery region
What side is most often neglected?
Right hand side damaged, left hand side neglected
Rates in the critical stage of up to 80% causing visual neglect of the left-hand side of space.
Sustained processing is?
Maintaining processing on current goals over extended periods of time.
How do we measure sustained attention?
Mackworth: Vigilance decrement: reduction in ability to detect targets over time
What brain areas are involved with sustained attention?
Right-sided frontal and parietal regions involved - more than other brain regions
When is executive/cognitive control impaired?
After frontal lobe injury
How do we measure executive attention?
Many different tasks have been used, e.g. Stroop test
Stroop test: Name the ink colour as fast as possible.
In the incongruent condition, where the ink colour is different to the word, we’re all slowed down to some extent.
Patients with frontal lobe damage may make many errors, actually saying the word instead of naming the ink colour.
Selective vs executive attention
Selective attention typically refers to the kind of processing involved in orienting attention towards a specific set of entities or representations while ignoring others.
Executive attention, in contrast, refers to attention processing related to responding and task execution.
