Attention Flashcards
(50 cards)
Neurologically what is responsible for arousal? How so
Thalamus is the key switchboard of the brain, the reticular nucleus forms a sheet around the thalamus. This sheet can gate all information (High arousal, excited) or block all information (no arousal; coma, deep sleep.) The reticular formation in the brainstem regulates the excitability (and thus permeability) can of the reticular nucleus surrounding the thalamus
How is arousal related to attention?
Attention and arousal are not the same, but without arousal no attention
Contrast voluntary and involuntary attention (3/4)
Voluntary; Endogenous, intentional, top-down, slower
Involuntary; exogenous, stimulus-driven, bottom-up, almost instantaneous
Contrast overt and covert attention
Overt attention- attention is directed to the same location as the eyes
Covert attention- attention is directed to another location than the eyes
Which broad brain regions direct top down and bottom up attention?
Voluntary (top-down) attention: Dorsal frontoparietal network
Stimulus driven (bottom up) attention: -Ventral frontoparietal network
Name three common neurological problems affecting attention
Neglect
Extinction
Ballint’s syndrome
What specific important regions are involved in the top down network?
Superior parietal lobe (SPL), Frontal Eye Fields (FEF), Middle Frontal Gyrus (MFG)
What specific important regions are involved in the bottom-up network?
TemporoParietal Junction (TPJ), Inferior Frontal Gyrus (IFG), Middle Frontal Gyrus (MFG)
What subcortical structure are also important for what aspects of attention?
Disengaging attention: problems when the tempoparietal junction is damaged
Moving attention: Problems when superior colliculi are damaged
Engage attention: Problems when pulvilinar is damaged
Where is damage affecting attention commonly located?
TemporoParietal junction
What damage usually results in neglect?
Bottom up network damaged; Right TPJ and IFG
What symptoms of neglect are usually shown
They generally take in information from the right side (ipsilateral side) and essentially become blind to the left visual field (contralateral side)
How permanent is neglect
It is often temporary but extinction often remains (difficulty in pointing out two similar objects in both fields at the same time)
What damage is associated with Ballint’s syndrome?
Much more severe: Dorsal posterior lobe
What symptoms are associated with Ballint’s syndrome?
- Simultanagnosia: unable to consciously see more than one object at the same time
- Optic ataxia: trouble with visual guidance reaching for objects
- Oculomotor apraxia: problems in making voluntary eye movements to objects
What is the capacity of the visual working and how is this recorded?
3-4, through a visual tracking test
What network is causing the limited capacity?
Top down attention network
What does the visual search task and the attentional blink task display about voluntary attention?
Its slow/ requires time
What does the visual search task display?
Conjunction feature search; looking for unique elements to find the object
What is involved in the attentional blink task?
Letters are shown in rapid succession (10 per second)
• 2 targets appear within this stream of stimuli (in this case numbers)
• At the end of the trial subjects need to report the 2 targets
• 1st target is called T1. 2nd target is called T2.
What are the usual results of the attentional blink task?
- T1 is almost always reported (in blue).
- T2 will be detected when presented directly following and long after T1
- When T2 follows 300ms after T1, attention is too busy processing T1 and then attention blinks
What evidence is there that when you give selective attention to one area, it is at the expense of attention to another? (2)
When asked to either recount faces and ignore scenes or vice versa, or passive viewing:Attention directed to a face -> higher activation in Fusiform Face Area. Attention directed to scene -> lower activation in FFA. Intermediate activation during passive viewing.
When people perform an easy task, visual motion evokes a strong response in V5/MT. When people perform a difficult task, visual motion evokes no response in V5/MT. Example that early selection takes place at high task load
How do the triggers differ in the Posner cueing task?
Central cue triggers- voluntary attention; the square in the centre will indicate a side for the square to appear (usually 80% valid) and you can decide whether to use this which will help or hinder your reaction time
Peripheral cue- stimulus driven attention; a stimulus will flash to either the left or the right which will automatically draw your attention to that side without a conscious decision
How does the validity of the cue matter?
If cue validity is too low, people don’t use the cue anymore in the central cue condition only