Lecture6

Question 1

What is the working definition of attention?

Answer 1

The recruitment & focus of resources to enhance a particular part of sensory input & exclude other parts

Question 2

Name the 2 components of attention

Answer 2

Recruitment of resources; Focusing them on selected aspects of sensory inputs

Question 3

What are the 4 properties of attention?

Answer 3

Selectivity; capacity; expectation; switching

Question 4

Define Capacity

Answer 4

The amount of perceptual resources that is available for a given task or process. It varies with the task & the individual

Question 5

Define Selectivity

Answer 5

At any given moment the fixed perceptual resources can be allocated to different subsets of information in a flexible way; Attention is selective in what gets processed & what does not

Question 6

What’s an example of how can selectivity can bring about an overt deployment of attention?

Answer 6

With eye movements - we focus on where our eyes are being directed, to the detriment of other regions in the visual field

Question 7

What are some examples of how selectivity can deploy covert attention?

Answer 7

We can move our attention but not our eyes; auditory attention (deploying attention around the space); attend to different properties of the same object/stimulus

Question 8

What does the early processing model argue?; What is an issue with this?

Answer 8

That unattended information is filtered out even before preliminary sensory processing; How can early selections be made without processing? It doesn’t tell the whole story

Question 9

What does the late processing model argue?; What is an issue with this?

Answer 9

That the filter is at later stages only after a significant amount of sensory processing has occurred; If selection occurs later after extensive processing, why bother selecting at all?

Question 10

The early vs late selection was thought to represent a pure attentional system. In which modality were these concepts first addressed?

Answer 10

Auditory

Question 11

What does the Cocktail phenomena show us about Shadowing?

Answer 11

Listeners could tell if the non-attended speech was in their native tongue, if it was a male or female voice & if their name was called (only in gross terms); they couldn’t tell semantic content

Question 12

If only early selective processing were true, how would this effect the Shadowing technique?; This indicates that…

Answer 12

Nothing from the non-attended speech would be processed; There is some information coming through

Question 13

What is a more flexible model in selective processing?; How does it work?

Answer 13

Perceptual Load/Bottleneck; When attended sensory input requires more resources, there are fewer resources available to process unattended; if attended is easily processed, then additional unattended can be processed; Bottleneck slides along a continuum depending on the perceptual load

Question 14

High perceptual load slides the attentional bottleneck towards….; Low perceptual load slides it towards….

Answer 14

Early selection (between sensory registration & perceptual analysis/semantic meaning); Late selection (between perceptual analysis/semantic meaning & higher analysis/awareness/response selection)

Question 15

If someone is good at multi-tasking it’s simply because they’re good at….; In relation to visual processing why is this so?

Answer 15

Switching; Because there is too much information in the visual array to be processed simultaneously

Question 16

What did Mack & Rock’s (98) inattention paradigm reveal about visual attention?

Answer 16

Simple sensory properties like location, colour & number could be determined above chance levels even on inattention trials. But in the inattention & divided attention trials, shape was more difficult to discriminate

Question 17

What did Hemholtz demonstrate about visual selective spatial attention?

Answer 17

If attending to a particular region of a wall in darkness, followed by a brief flash of light, he was able to read letters on the wall in that region

Question 18

What does the Posner Attentional Cuing Paradigm tell us about the costs & benefits of attending to specific locations in space?

Answer 18

Attending to validly cued locations resulted in a shorter response time than the baseline (benefit); attending to invalid locations resulted in a longer response time than the baseline as they had to move attention from where they’d been cued (cost)

Question 19

What are voluntary shifts in attention referred to as?; What occurs?

Answer 19

Endogenous cues; Attention must be voluntarily pushed from the central cue to the cued location

Question 20

What are involuntary shifts in attention referred to as?; What occurs?

Answer 20

Exogenous cues; Attention is drawn to the location of the cue, it’s usually a flash or movement & can’t be ignored

Question 21

Name and explain the 3 components of shifting attention

Answer 21

Disengagement - in order to move attention we must first disengage from current target; Movement - attention is now free to move & must be directed to the new target ; Engagement - attention must then be reengaged on the new target

Question 22

What can result in the loss of disengagement?

Answer 22

Damage to the parietal lobe (especially right); they can’t move their attention from a particular object (extinction)

Question 23

What does damage to the superior colliculus impede?

Answer 23

Movement; Can also compromise eye movement (they don’t know where their eyes should go)

Question 24

What compromises the function of engagement?

Answer 24

Damage to regions in the thalamus (sensory input relay)

Question 25

What does moving attention from one point to another require?

Answer 25

The coordinated action of 3 separate brain areas (Parietal lobe, Superior colliculus, Thalamus)

Question 26

What 2 metaphors can be used to describe visual attention?; Both of these can be….

Answer 26

Spotlight (illuminates the object in its focus region) & Zoom-lens (has variable spatial scope); Combined as a variable zooming spotlight that can be moved around

Question 27

How does the Local/Global task support the zoom-lens metaphor?; Unless directed, what are autistic patients quicker to identify?

Answer 27

Narrow field = fine resolution; wide field = coarser detail eg. 6’s (local) forming a large 8 (global); The local stimuli

Question 28

What does Distributed Attention feature?

Answer 28

Parallel processing & visual “pop-out” - visual processing occurs simultaneously over the whole visual field

Question 29

What does Focused Attention feature?

Answer 29

Serial processing - visual processing is a series of attentional “fixations” each covering a different region of the visual field

Question 30

How is the target defined in a Parallel search/”pop-out”?

Answer 30

By a single feature (eg. colour/orientation) so equally fast to find between trials (focused attention)

Question 31

What does a serial search require?

Answer 31

A number of attentional fixations; there are 2 features of distractors, making the target more difficult to detect & more movement of attention to find it (focused attention)

Question 32

What is Cognitive Tunneling?

Answer 32

Inattentional blindness to the real world (cognitive resources are directed at one thing so we miss what is right in front of us)

Question 33

What is Change Blindness?

Answer 33

Lack of attention to an object causes a failure to perceive it; we are poor at detecting changes in a picture if they aren’t the focus of attention

Question 34

What occurs with the Stroop Effect?; What does it suggest?

Answer 34

Conflicts between the semantic identity of the word & its colour interfere with speeded naming; We have little control over what we can selectively attend to in a given object

Question 35

What is the Stroop Effect consistent with?; Does it go in the other direction?; What can the effect extend to?

Answer 35

Late Selection; No, reading words with different colours is just as fast as with same colours; Pictures such as a foot inside a silhouette of a hand

Question 36

How was the Auditory Endogenous attention experiment conducted?; What did they find?

Answer 36

The Event Related Potentials (ERPs) were compared between the subjects attended ear & unattended ear; They found higher amplitude N1 signals for attended ears, at 400 there was a large positive deviation suggesting deeper semantic processing

Question 37

In a cued visual attention test, where observers covertly attend to either the left or right location as cued by the experimenter, what did ERPs recorded over the right occipital cortex show?

Answer 37

Attention enhances contralateral occipital activity; valid cues show enhanced P1 & N1 relative to invalid cues

Question 38

In a single unit recording with monkeys where they measured activity in V4 & IT cells, what did they find?

Answer 38

The cells responded more strongly when the animal attended to the location on the screen where the target would appear than when they did not direct their attention there. Receptive fields appeared to be restricted to attended location

Question 39

What did the fMRI study of voluntary spatial attention show where participants fixated centrally & were required to detect a surrounding plaid pattern?; What does the second effect suggest?

Answer 39

BOLD responses were high when attention was directed to the surround & the pattern was present, & were also high when the pattern was absent; seems to be an effect of attention that prepares relevant brain areas for the task

Question 40

What occurs in patients with Spatial Neglect (Hemi-neglect)?; What parts of the brain are generally damaged?

Answer 40

They tend to ignore half of the visual field, they have sensory processes but lack the ability to attend to the locations; Posterior parietal lobe (disengage), Superior colliculus (move), Pulvinar (enhance)

Question 41

What did the mental imagery study of the Piazza in Milan show strong evidence for?

Answer 41

That the spatial neglect deficit is attentional & not sensory

Question 42

What does extinction effect?

Answer 42

The ability to disengage. Patients with right hemisphere lesions can direct their attention to either side of visual space, but if presented with simultaneous stimuli they can’t disengage attention to the opposite side of fixation (they’ll only report the ipsilateral side)

Question 43

What was found in the PET study which assessed left & right parietal lobe activity whilst deploying visual attention?

Answer 43

When attention was directed to the left visual field, activation in the right parietal lobe increased, with little activity in the left parietal lobe; but when attention was directed to the right visual field, activation was increased in BOTH left and right parietal lobes

Question 44

If left parietal damage partially impairs attention in the right visual field, what happens?; What about right parietal lesions?

Answer 44

Owing to the functioning right parietal lobe, attention is still deployed to both visual fields; The ability to attend to the left visual field is destroyed, but right visual field is left intact because of functioning of the left parietal lobe.

Question 45

Selection seems to take place both early & late with general attenuation of signals occurring…; & further selection occurring…

Answer 45

In early processing; later in processing

Question 46

Attention is required for processing of…

Answer 46

Complex information

Question 47

Selection of properties of objects is less straight forward than what?

Answer 47

Spatial attention (i.e Stroop Effect)

Question 48

Attention can modulate responses to…; & heighten activity in the…

Answer 48

Receptive fields; Primary visual cortex

Question 49

Damage to the parietal lobe compromises…

Answer 49

Attentional processes leading to neglect of the contralateral side of visual space

Question 50

Right parietal damage is more debilitating than…

Answer 50

Left parietal damage