LECTURE 11 - FINAL FROM HEREON

Question 1

ATTENTION

Answer 1

Ultimately about selecting a subset of the available
information in the world for further neural processing

• Alertness and arousal, vigilance (ability to maintain sustained attention), selective attention and divided attention (limited resources theory explains why we are bad at divided attention, multiple resources theory says some resources are used for certain occasions - why its easy to pay attention to one visual and one auditory task simultaneously rather than two visual/auditory tasks for the same )

Question 2

Alertness and arousal

Answer 2

Most basic levels of attention

Question 3

Vigilance

Answer 3

Ability to maintain alertness continuously over time

Question 4

Selective attention

Answer 4

The selection of information essential to a task

Question 5

Divided attention

Answer 5

When we have to split attention across tasks

Question 6

Reticular Activating System

Answer 6

Responsible for overall arousal/alertness and sleep wake cycles

• Dorsal and Ventral Subsystem

Question 7

Dorsal Subsystem for Reticular Activating System

Answer 7

Projects to the cortex via the thalamus
* Relies on acetylcholine

Question 8

Ventral Subsystem for Reticular Activating System

Answer 8

Projects to the cortex via the basal forebrain
* Relies on serotonin and norepinephrine

Question 9

Thalamus

Answer 9

Keeps you alert and awake using glutamate to modulate level of arousal in the cortex
* Damage can be enough to result in coma

Question 10

Vigilance and Sustained Attention

Answer 10

• Requires both cholinergic and noradrenergic systems
• More effort needed to sustain attention requires more
  acetylcholine
• The noradrenergic system prepares the brain to receive information
• Thalamus interfaces between arousal & sustained attention

Question 11

Attention & Eye Movements

Answer 11

• Simplest way to direct attention
• Fixate your eyes on something
• Lots of very small muscles allow the eye to move in a wide variety of directions and respond very quickly - saccade versus smooth motion graphs

Question 12

Covert Attention

Answer 12

• Fixate center
• Covertly (without moving the eyes) shift the “spotlight of attention” to a specific location
• Electric spark briefly illuminates screen
• Result: possible to process the letters in that covertly attended location

Question 13

Covert spatial attention

Answer 13

Attending to different regions of space without moving your eyes can enhance processing at the attended
location (at the cost of decreased processing at the unattended location)

Question 14

Object-based attention

Answer 14

Parts of an “object” get preferential
enhancement of processing even if they are far in space from the
focus of spatial attention

Question 15

Feature-based attention

Answer 15

Attend to objects based on features (e.g. color or shape)

Question 16

Bottom-up Selective Attention

Answer 16

an aspect of the stimulus itself causes it to be attended

Question 17

Top-down Selective Attention

Answer 17

person determines how to direct their attention

Question 18

Does attention operate early or late in
processing?

Answer 18

READ THE GRAPHS

Question 19

Simplified feedback pathway from PFC to thalamus

Answer 19

Prefrontal Cortex -Excitatory-> Thalamic Reticular Nucleus -Inhibitory -> Lateral Geniculate Nucleus

Question 20

Source of attentional control

Answer 20

brain region that sends a signal to other region(s) to guide processing

Question 21

Site of attentional control

Answer 21

brain region at which processing is modulated to enhance attention to a specific attribute, location, item, or other salient dimension

Question 22

Sources of Attentional Control

Answer 22

• Activity in frontal regions when attention is to be directed to a stimulus regardless
  of whether it is present or not
• Frontal eye field (FEF) and supplementary eye field (SEF)

Question 23

Sites of Attentional Control

Answer 23

• Activity in regions processing the stimulus when it has appeared and is physically present
• V4, a posterior visual processing region, is one such example

Question 24

Divided Attention

Answer 24

Divided attention refers to conditions under which you must (attempt to) split your attention between different sources of information or different tasks

Question 25

Hemineglect

Answer 25

Patients with hemineglect do not pay attention to one side of the space. Usually results from brain injury or damage to the right parietal lobe. People with right hemisphere show greater degree of damage and missed items, could be explained as right hemipshere is more associated with spatial.

Question 26

Right hemisphere lesion

Answer 26

Fails: * Notice items on the left side of the world - spatial neglect * Draw the left side of objects - allocentric neglect * Use the left side of the body - personal neglect

Question 27

Neural Underpinnings of Hemineglect

Answer 27

Damage to a diverse set of right hemisphere regions can lead to hemineglect * Indicates that attention allocation likely arises from a network of brain regions (rather than a single specific location in the brain)

Question 28

Reticular Activating System

Answer 28

responsible for overall arousal and sleep-wake cycle. Damage results in coma. Cell bodies located in the brain stem. Dorsal route: Thalamus to cortex - uses acetylcholine. Ventral route: Basal forebrain to cortex - noradrenergic and serotonogeric system. Locus Coeruleus - Firing here prevents sleep. Where noradrenergic system are located. Serotonin - suppresses rapid eye movement during REM

Question 29

Thalamus

Answer 29

keeps us awake and alert. Medial, dorsal, intralaminar and reticular nuclei

Question 30

Early versus Late selection viewpoint

Answer 30

Early - Attentional selection occurs at an early stage of processing before items are identified. ERP and MEG's show relative automatic filtering occurs very soojn after the receipt of a stimulus Late - Selection occurs only after the sensory processing is complete and items have been identified and categorized

Question 31

Bottom up versus top down

Answer 31

Bottom up - Stimulus catches your attention (inferior parietal, associated with hemineglect) Top - Person directs attention to stimulus (usually by superior parietal)

Question 32

Frontal lesions - motor response hemineglect Pariteal lesions - sensory hemineglect

Answer 32

Anterior cingulate cortex - activation when selection of correct action is difficult

Question 33

Sources of attentional control versus sites where its implemented

Answer 33

Sources of attentional control - thought to send signals to brain regions biasing info Implementation sites: Brain regions where processing is modulated to enhance attention to a specific attribute

Question 34

Biased competition model

Answer 34

Can be induced in a top-down way such as looking for a spoon instead of a fork for soup. Bottom-up where intensity of light attracts you to an object quicker than a duller one.

Question 35

Model for distributed but overlapping system

Answer 35

4 systems: Reticular activating system: Vigilance and arousal Cingulate Cortex: Impart motivational significance to information Posterior parietal region: Provide a sensory map to direct attention to certain object Frontal region: Provide motor programming for moving attentional focus

Question 36

Altering, Orienting anf Executive Attention Model

Answer 36

Alert: Allows people to be sensitive to oncoming info, noradrenegric system, locus coerulus, thalamic region Oritenting: Superior colliculus, acetylcholine Executive: Basal ganglia, anterior cingulate, dopamine

Question 37

Dorsal versus Ventral System

Answer 37

Dorsal - intraparietal cortex, superior frontal cortex, etc. Ventral - tempoproparietal cortex, inferior frontal cortex, anterior insula For detection of stimuli and active when stimuli is unexpected.

Question 38

Default Network System

Answer 38

Medial orbitofrontal regions, superior frontal regions, posterior cingulate cortex, inferior parietal lobe and medial temporal lobe

Question 39

Source of attentional control

Answer 39

brain region that sends a signal to other region(s) to guide processing. * Activity in frontal regions when attention is to be directed to a stimulus regardless of whether it is present or not * Frontal eye field (FEF) and supplementary eye field (SEF)

Question 40

Site of attentional control

Answer 40

brain region at which processing is modulated to enhance attention to a specific attribute, location, item, or other salient dimension * Activity in regions processing the stimulus when it has appeared and is physically present * V4, a posterior visual processing region, is one such example

Question 41

Divided attention

Answer 41

* Divided attention refers to conditions under which you must (attempt to) split your attention between different sources of information or different tasks