Attention

Question 1

What is attention?

Answer 1

The limited-capacity process that allows the preferential processing of certain sensory or imaged info at the expense of other available stimuli.

Question 2

What is the most basic level of attention?

Answer 2

Alertness and arousal - it lowers when sleepy

Question 3

What are higher levels of attentional processing? (5)

Answer 3

• Focused attention
• Sustained attention (vigilance)
• Selective attention
• Alternating attention
• Divided attention

Question 4

What is focused attention?

Answer 4

The inhibition and redirection of attention - the ability to respond discretely to visual, auditory or tactile stimuli

Question 5

What is sustained attention?

Answer 5

The ability to maintain a consistent behavioural response during continuous and repetitive activity.

Question 6

What is selective attention?

Answer 6

The ability to maintain a behavioural or cognitive set in the face of distracting stimuli.

Question 7

What is alternating attention?

Answer 7

The capacity for mental flexibility that allows for a shift in attention and focus between tasks that have different cognitive requirements.

Question 8

What is divided attention?

Answer 8

The ability to respond simultaneously to multiple tasks.

Question 9

What is multiple resource theory?

Answer 9

A limited set of distinct resource pools exist, each of which can only be applied to certain types of processes.

Question 10

What is forward span attention and what is backward span attention?

Answer 10

• Concentration

- Working memory

Question 11

What structures are involved in attention?

Answer 11

RAS, superior colliculus, thalamus, posterior parietal lobe, frontal lobe and cingulate cortex.

Question 12

How is the Reticular Activation System involved in arousal?

Answer 12

It regulates cortical activation for overall arousal - the sensory input charges the RAS. It’s involved in controlling sleep wake cycles. It also has diffuse connections to most regions of the cortex, meaning it can modulate for arousal throughout the brain.

Question 13

What is the RAS dorsal route to the cortex?

Answer 13

RAS - thalamus - cortex

Question 14

What is the ventral route to the cortex?

Answer 14

RAS - hypothalamus - basal forebrain - cortex

Question 15

What network is involved in sustained attention?

Answer 15

RIGHT FRONTO-PARIETAL-THALAMIC NEURAL NETWORK:

• Frontal lobe: directs attentional resources
• Posterier parietal love: focuses conscious attention, overall allocation of attentional resources to stimulus
• Thalamus - relay station

Question 16

Two kinds of selective attention:

Answer 16

1. Bottom up - a bright light.

2. Top-down - looking for a yellow flower.

Question 17

Selective attention: early selection vs late selection

Answer 17

• Early selection: before the items are identified

- Late selection: after the items have been identified and categorised.

Question 18

Two assumptions of feature integration theory:

Answer 18

1. Rudimentary perceptual features of objects are coded in parallel and prior to attention
2. Attention is the glue that binds the features together

Question 19

Brain areas involved in selective attention: (5)

Answer 19

• Superior colliculus: bottom up process, orientating to visual stimuli.
• Inferior colliculus: orienting to auditory stimuli
• Thalamus: filtering function, LGN input from eyes and pulvinar filters distractions.
• Parietal lobe: overall allocation of attentional resources.
• Medial and Lateral prefrontal cortex: Selection of appropriate motor responses, top-down attention control

Question 20

What is the stroop test?

Answer 20

Colours written in different colours - proved the role of the cingulate cortex in response selection.

Question 21

4 main parts of the attentional system:

Answer 21

1. Arousal system
2. Orienting system
3. Perceptual system
4. Executive system

Question 22

3 network models of attention:

Answer 22

1. Mesulam, 1981 - anatomical model of spatial attention and unilateral spatial neglect
2. Posner and Rothbart, 2007 - anterior and posterior attention model
3. Corbetta and Shulman, 2002 - controls of goal directed and stimulus driven attention in the brain

Question 23

Mesulam 1981 - anatomical model of spatial attention and unilateral spatial neglect

Answer 23

Neural network:
- Frontal eye fields modulates and coordinates motor programmes
- Parietal generates sensory maps
- Cingulate cortex regulates motivation and emotional significance
- RAS deals with vigilance and arousal
The networks overlap to orient attention

Question 24

Implication of Mesulam’s model: (3)

Answer 24

1. It implies that a lesion confined to one brain region may affect not only attention, but other behaviours
2. Because the model is strictly localizationist, damage to attention can be caused by damage to other regions
3. The most severe disruption of a complex function will occur after damage to more than one region.

Question 25

Posner and Rothbart, 2007.

Answer 25

Attention has 3 major functions:

1. Achieving and maintaining an alert state
2. Orientating to events
3. Orchestrating voluntary actions

Question 26

P&R: Alerting network

Answer 26

Mobilizes and sustains alertness for processing high priority targets - involves RAS, thalamus, parietal regions and right frontal cortex area

Question 27

P&R: Orienting system

Answer 27

Visual orienting - involves parietal lobes, temporoparietal junction, lateral pulvinar nucleus and superior colliculus. May be modulated by acetylcholine

Question 28

P&R: Executive system

Answer 28

Anterior system that control and coordinates other brain regions for voluntary attention - lateral prefrontal cortex (W.M.), basal ganglia and anterior cingulate (error detection); dopamine involved.

Question 29

How is the hierarchy of attentional processing structured?

Answer 29

Anterior to posterior

Question 30

Corbetta and Shulman, 2002

Answer 30

Two partially segregated networks carry our different attentional functions:

1. A dorsal subsystem that works top-down
2. A ventral subsystem that works bottom-up

Question 31

What is the default mode network?

Answer 31

A group of areas that are typically more active during rest than during an active task performance.

Question 32

What is hemineglect?

Answer 32

Loss of conscious awareness of an aspect of space despite adequately functioning sensory and motor systems.

Question 33

How does hemineglect manifest?

Answer 33

• When asked to point out the midpoint, the right hand side is favored
• Colliding with objects and people on the left side
• Reading and drawing is restricted to the right hand side
• Ignorance to the space contralateral to the lesion

Question 34

How does hemineglect differ from hemianopsia?

Answer 34

Hemianopsia entails blindness over half the field, hemineglect does not have a lack of sensory input, just a lack of attention

Question 35

Theories on hemineglect

Answer 35

• Individuals lack an internal mental representation of the neglected side of space
• Competition between hemispheres

Question 36

Treatment for hemineglect

Answer 36

Top-down and bottom-up approaches - visual scanning training and manipulating sensory input to the brain.

Question 37

What is the right hemisphere more important for?

Answer 37

Overall arousal and attention

Question 38

What is the gradient of attentional neglect?

Answer 38

The further an item is into the neglected visual field, the less attention it gets

Question 39

How does the Gradient of Attentional Allocation differ between hemispheres?

Answer 39

The left eye has a steeper gradient with concern to attention paid to the contralateral side.