Attention

Question 1

What is attention?

Answer 1

An umbrella term used to refer to processes someone uses to choose information for further processing
–Alertness and arousal
–Vigilance
–Selective attention
–Divided attention

Question 2

Alertness and Arousal

Answer 2

Most basic levels of attention

Question 3

Vigilance

Answer 3

Ability to maintain alertness over time

Question 4

Selective attention

Answer 4

The selection of information essential to a task
When we selectively attend to a stimulus, mental effort is required
– focusing and concentrating
2 types:
– bottom up attentional selection
– top-down attentional selection
Dichotic Attention (listening/ reading/ etc.)
The response to stimulus is enhanced when is it present in the attended location compared to when it’s not
— the ear you are attending to/ giving some attentional focus experiences more activation when a tone is heard.

Question 5

Divided attention

Answer 5

Split attention across tasks

Question 6

Where does attention occur?
What are critical brain areas for attention?

Answer 6

No specific place for it in the brain
Attentional processing is performed by/ associated with a functional network of different subcortical and cortical brain area
—Critical brain areas for attention:
> Reticular activating system
> Superior Colliculus
> Thalamus (LGN and Pulvinar)
> Anterior cingulate cortex
> Parietal Cortex
> Frontal Cortex

Question 7

Reticular Activating System functions

Answer 7

– overall arousal and sleep-wake cycles
– Damage can result in a coma
– Dorsal Sub-system
–Ventral Sub-system

Question 8

RAS Dorsal Subsystem

Answer 8

Projects to the cortex cia the thalamus
> relies on Aceytlcholine

Question 9

RAS Ventral Subsystem

Answer 9

– Projects to cortex via basal forebrain
> 2 Pathways, Serotonin (raphe nucleus) and Norepinephrine (locus coerelius)

Question 10

Vigilance and Sustained attention systems

Answer 10

– Cholinergic and Noradrenergic systems
— More effort needed to sustain attention = more acetylcholine
— Noradrogenic prepares the brain to receive information
– Thalamus interfaces arousal and sustained attention
– Cortical regions (especially right hemisphere) involved
— Activation of right hemisphere seen in vigilance tasks

Question 11

Bottom-up attentional selection

Answer 11

Some intrinsic aspect of the stimulus causes your attention to be brought to it
- Subcortical areas play a role in mediating stimulus-driven/ involuntary attention

Evolutionary perspective
– subcortical orienting mechanisms developed first, responsible for mediating more basic stimulus driven processing

Question 12

Top-down attentional selection

Answer 12

Individual decides where to direct attention
- Cortical areas (parietal and frontal cortices) play a role in mediating goal-driven/voluntary attention

Evolutionary perspective
– Cortical orienting mechanisms evolved more recently and are responsible for higher-level goal-driven attention shifts.

Question 13

Attentional Selection

Answer 13

• Subcortical areas play a role in mediating stimulus-driven/ involuntary attention
• Cortical areas (parietal and frontal cortices) play a role in mediating goal-driven/voluntary attention

Evolutionary perspective
– subcortical orienting mechanisms developed first, responsible for mediating more basic stimulus driven processing
– Cortical orienting mechanisms evolved more recently and are responsible for higher-level goal-driven attention shifts.

Question 14

Dichotic Attention (Selective attention)

Answer 14

Attended vs. Unattended stimulus
Paying attention to one thing, but not the other, despite both being perceived (but not processed)

Question 15

Selection Models

Answer 15

Early-Selection Viewpoint
Late-Selection Viewpoint

Question 16

Early-Selection Viewpoint Model

Answer 16

Selection occurs earlier in processing, before items are identified
Attended speech&raquo_space; Attentional Speech&raquo_space; Semantic analysis&raquo_space; Longer-term memory

Problems:
– even unattended perception is processed/ influences overall hearing

Question 17

Late-selection Viewpoint Model

Answer 17

Selection occurs only after sensory processing is complete and items are already identified and categorized
Attended speech&raquo_space; Sensory buffer&raquo_space; Attentional Selection&raquo_space; Longer-term memory
Problem:
Hard to process everything that comes at you

Question 18

Intermediate Selection Model

Answer 18

Attended speech&raquo_space; Sensory Buffer&raquo_space; Semantic Analysis&raquo_space; Longer-term memory
– If something we recognize is brought up, we can skip past all the levels
– Things you are paying attention are prioritized when attending to something, higher general threshold for unattended speech, lower threshold for important things

Question 19

Superior Colliculus: Automatic Orienting

Answer 19

– Plays a role in the localization of visual stimuli, the control of saccades, and stimulus-driven attentional shifts to stimuli in visual space
– Superior colliculus is well-situated for attentional processing and linking eye movements
— set of neurons that quickly respond to visual stimuli
— retinotopic map of the contralateral side of space
— Has a different set of neurons sensitive to both sensory characteristics and to orienting movements
— The inferior colliculus plays a similar role for auditory info
EVIDENCE:
– Lesions to this area disrupt attention shifts

Question 20

What two major parts of the Thalamus play a role in Selective Attention?

Answer 20

2 Major parts (nuclei): Pulvinar and LGN

Question 21

LGN and Selective attention

Answer 21

Thalamus
– gatekeeper to the cortex
Can enhance and suppress information based on relevance

Question 22

Pulvinar and Selective attention

Answer 22

Thalamus
- Aids in regulating information transmission between cortical regions processing relevant information
- helps synchronize activity between brain regions
- filtering: freater activation of the pulvinar when identifying small targets surrounded by distractors as opposed to large targets with no distractors

Question 23

Selective attention and Parietal Lobe

Answer 23

Involved in the overall allocation of attentional resources to a particular stimulus or task.
Plays a role in selecting information in a more precise manner after the early gating of sensory information by the thalamus.
- Involved in types of attentional selection:
– Types of selection involve different regions of parietal lobe: the superior parietal lobe, the inferior parietal lobe, and the intraparietal sulcus.

Question 24

Regions of the Parietal Lobe

Answer 24

Superior parietal lobe (SPL) is involved in “top-down” influences on attention directed by the person’s goals or desires rather than stimuli in the environment.
Inferior parietal lobe (IPL) of the right hemisphere are more involved in more bottom-up aspects of attention control.
Intraparietal sulcus (IPS) is where these two streams of information are thought to be integrated.

Question 25

Superior Parietal Lobe

Answer 25

- Top-down influences on attention, directed by the individual

Question 26

Inferior Parietal Lobe

Answer 26

Right hemisphere Bottom-up aspects

Question 27

Intraparietal sulcus

Answer 27

Other two parietal streams of information are thought to be integrated

Question 28

Visual Search

Answer 28

- If something makes something stand out/ look different, visual search is faster - The more objects, the harder this process gets - Depends on features of the target

Question 29

Feature Integration Theory

Answer 29

- Targets defined by only one feature will "pop out" --- preattentive/ parallel search - Targets defined by feature combinations requires attention to put features together --- attentive/ serial search --- gets hard the more objects/ visual noise there is The theory: Attention allows the feature of an item to be "glued" together - Basic visual features are detected automatically and processed in parallel across all locations in a display --- attention is required to bind these different features to form the percept of an item

Question 30

Feature Integration Binding Process

Answer 30

- Damage to **parietal** regions disrupts the ability to bind features together -- Patients with such deficits cannot detect the conjunction of features, whereas their ability to detect a single feature remains intact -- TMS applied to the ***right* parietal cortex** of neurologically intact adults increases the time for conjunction searches but not simple feature searches

Question 31

Salience Maps

Answer 31

- Some information prcessed automatically helps influence where attention is directed (bottom-up) - Top-down information is also an influence - Both these influences form a salience map, which helps decide where attention should be directed --- the IPS (intraparietal sulcus) is essential for salience maps (part of the parietal regions)

Question 32

Feature Maps

Answer 32

- Different signals for the presence of each feature - If a unique feature: target can be found only using the feature map, attention goes to that location on the master map - If no unique feature: Attention must be directed in a serial search to locations in the master map - Attention to a master map location provides access to information at that location in each of the feature maps - This integrates the features possessed by the item at the location

Question 33

Illusory Conjunctions

Answer 33

→ Attention is required to combine the features of objects → Attention is also required to precisely determine the locations of object features → When attention is limited, may not properly put features together in the right location → Features can get mixed up: illusory conjunction

Question 34

Inattentional and Change Blindness

Answer 34

- When attention is focused on a location or an object, it is withdrawn from other locations or objects - Unattended objects are processed less efficiently than the object that is attended to

Question 35

Neural Bases of Divided Attention

Answer 35

- Divided Attention occurs when attention is split between different sources of information or between different tasks - No consensus on what neural systems allow for multitasking --- Some suggest increased activity in prefrontal regions --- others argue that increased prefrontal activity is because of greater demands of the brain under divided tasks rather than divided attention itself

Question 36

Automaticity

Answer 36

- Learning a skill requires careful attention - with training, attentional demands decrease - some skills/ tasks become automatic, requiring minimal attention to perform - multitasking can be possible when attentional demands of different skills/ tasks decrease to the point where performing both at the same time does not exceed our capacity for attention - Tasks that require cognitive processing cannot be automatic

Question 37

Stroop Effect- Is reading automatic?

Answer 37

- Stroop effect shows that reading is automatic - Individual words: yes, understanding sentences: no - Regardless of practice, comprehension of phrases never becomes automatic - This is why there are limits to multitasking. Things that require conscious processing aren't automatic

Question 38

Response-Related Selection

Answer 38

- Anterior Cingulate Cortex, more involved the harder a task gets --- Intracranial recordings show alterations in activity just prior and after a response --- neuroimaging findings suggest that these regions specifically increase their activity when response mappings are hard - ACC involved in response section --- activated during Stroop interference

Question 39

Lateral Prefrontal Cortex and Goal Selection

Answer 39

- Lateral prefrontal regions serve as sources for top-down attentional control - they send signals to posterior brain regions that act as the sites of attentional control that are actively involved in the selection process -- bias towards processing certain information that you choose ------------- Prefrontal regions are top-down sources of attentional control that modulate activity in posterior brain regions

Question 40

Source + Sites of Attentional Control

Answer 40

Sources: Prepping Stuff Sites: where it occurs? Attention can act to select information in a variety of manners Selective attention can be directed to a particular position in space, a particular item attribute, or a particular object Effects of attention are observed in regions of cortex that are specialized to process the attribute on which information is being selected (space-based, object-based, attribute-based)

Question 41

Alerting, Orienting, and Executive Attention *Model*

Answer 41

Attention can be divided into 3 systems: 1. Alerting 2. Orienting 3. Executive Attention

Question 42

Alerting (Alerting, Orienting, and Executive Attention model)

Answer 42

Allows the brain to maintain a tonic level of arousal and to respond to signals warning of upcoming events ---> Involves the: >>> Locus Coeruleus >>> Thalamic regions >>> Frontal and Parietal regions >>> linked to norepinephrine

Question 43

Orienting (Alerting, Orienting, and Executive Attention Model)

Answer 43

Aligns attention w/ sensory signals and selects among multiple sensory inputs ---> Involves the: >>> Superior colliculus >>> Parietal areas >>> Frontal eye fields >>> linked to acetylcholine

Question 44

Executive Attention (Alerting, Orienting, and Executive Attention Model)

Answer 44

Controls how attention is directed to **goals** and desires ---> Involves the: >>> Basal Ganglia >>> Lateral Prefrontal Cortex >>> Anterior Cingulate >>> Linked to dopamine

Question 45

Dorsal Attention System

Answer 45

System prepares and applies top-down (**goal-directed**) selection of stimuli and responses >>> composed of portions of the intraparietal cortex (Intraparietal sulcus = IPS), superior frontal cortex, and frontal eye fields

Question 46

Ventral Attention System

Answer 46

Detects and reorients attention to behaviourally relevant stimuli, especially notable (salient) or unexpected >>> composed of the temporoparietal cortex (temporoparietal junction = TPJ), inferior frontal cortex, and anterior insula >>> Mainly lateralized to the right hemi

Question 47

Dorsal and Ventral Attentional System interactions

Answer 47

> Exchange of inputs said to occur between the TPJ (Temporoparietal junction) and the IPS (Intraparietal Sulcus) > Ventral is sensitive to new stimuli, dorsal precisely locates these stimuli once attention is brought to it by the ventral