week 6 Attention: Structure, Capacity, & Control

Question 1

Cost of Divided Attention (Moray, 1970) pure tone detection

Answer 1

Auditory signal detection task of Pure tone stimuli with different intensity
-the participant must detect a loud bep
three condition:
Selective: Monitor for targets on one channel only (67%)
Exclusive OR (XOR): Monitor both channels, no simultaneous targets (54%)
Inclusive OR (IOR): Monitor both channels, simultaneous targets possible 31$

Question 2

result of Cost of Divided Attention (Moray, 1970)

Answer 2

Compare simultaneous targets (AND trials) and nonsimultaneous (OR trials)
Moderate cost of divided attention (OR < selective)
Large cost of simultaneous detection (AND < OR)

Question 3

Implications of Moray Study

Answer 3

• late attention predict the AND < OR finding because two simultaneous selection targets will both be selected by ‘pertinence’ and compete to get through the filter, with this competition giving an AND deficit
• The finding that OR < SEL was predicted by early selection because there is attenuation with divided attention but not by late selection
  -both thoery doesnt work, need for a new one?

Question 4

Structural and Capacity Theories (The 70’s View)

Answer 4

Structural (Bottleneck) Theories
Some neural structures can only deal with one stimulus at a time
Competition produces processing “bottleneck” (filter theory)
(ES: bottleneck getting into LTM; LS bottleneck getting out)
Capacity (Resource) Theories:
Information processing is mental work
Work requires activation of neural structure
Limited capacity to activate structure

Question 5

Capacity theory (Kahneman, 1973)

Answer 5

-there is a fixed amount of attention that can be divided into different task
® According to this theory, a reduction of capacity produces a deficit in divided attention tasks.
® Differs from structural theories, because under this theory capacity can be allocated flexibly to simultaneous tasks

Question 6

Interfering Effects of Divided Attention

Answer 6

•Strayer and Johnston (2001): Talking on a mobile phone interferes with driving (sharing capacity reduces accuracy and increases RT)
•100 ms delay in respond 60 km/h ~ 1.7 m

Question 7

Dual Task Performance (Li et al., 2002)

Answer 7

® The costs (in terms of errors etc.) of dividing attention (doing two things at once) will depend on the capacity demands of each of the tasks.
® Li et al. (2002) had participants complete an attention demanding central task, and an easy or hard peripheral task. The difficult task was much more affected by central load.

Question 8

Inattentional blindness

Answer 8

-Cartwright-Finch & Lavie (2007) had participants examine which arm of a flashed cross was longer. During this experiment, a clearly visible square was not detected by participants.
® This suggests that the demanding central task used up all available attentional capacity, leading to the inattentional blindness in the form of missing the square

Question 9

Study capacity by dual task trade-offs:

Answer 9

® We can vary the proportion of attention allocated to two tasks in a dual task paradigm.
® The shape of the trade-off curve (attention operating characteristic (AOC)) tells us about the capacity demands of tasks.
® There is a ‘graceful degradation’ of performance as available capacity is reduced from one task and allocated to another

Question 10

Auditory & Visual Dual Tasks:

Answer 10

Bonnel & Hafter (1998) had participants complete easy auditory & visual tasks (detecting a spot of light or tone); and difficult auditory and visual tasks (discriminating increases from decreases in intensity of a spot or tone).
® Found that there was an attentional trade-off for the difficult tasks, but not for the easy detection ones. This is consistent with the idea that simple tasks such as detection can be done without much attentional capacity, but more difficult tasks such as discrimination between two similar stimuli requires far greater attentional capacity

Question 11

Pros & Cons of Capacity Theory:

Answer 11

® Emphasizes divided attention, flexibility of attentional control.
® Can make capacity theories mathematically precise using decision-making theories.
® Shortcoming is its vagueness – can always come up with a capacity explanation.

Question 12

Attentional orienting (1980s)

Answer 12

® Shifts of attention are called attentional orienting.
® Attention shifts precede eye movements, and can occur without them.
® ‘Covert attention’ is movement independent of eye movements.
® These shifts in attention can be top-down (where you decide to shift your attention) or bottom-up (where something captures your attention). Clinical patients show deficits of both kinds – failure to focus attention, failure to disengage attention.

Question 13

Two way of Attentional orienting (1980s)

Answer 13

There are two attentional orienting systems, engaged by different kinds of cues –endogenous (voluntary) or exogenous (reflexive).
The endogenous system requires cognition – it needs to interpret information (e.g. central (symbolic) cues).
The exogenous system is direct & spatial (doesn’t need to interpret information – e.g. peripheral (spatial) cues).

Question 14

Posner: The “Spotlight of Attention”

Answer 14

Shifts of attention likened to moving spotlight
Selective enhancement for stimuli “illuminated by the beam”
Expresses selective, limited-capacity idea in spatial terms

Question 15

Spatial Cuing Paradigm (Posner)

Answer 15

Attract attention to A, present stimulus at A or B, compare performance
-present a cue, wait a moment before presenting the stimuli (SOA, stimulus onsent asynchrony)
-SOA can vary 100-300 ms
-Saccades take about 200 ms. Need to monitor eye movements at long SOAs, not necessary at short SOAs
-measure the RT

Question 16

Spatial Cuing Paradigm (Detection Target) trial type

Answer 16

•Cued (valid) trial: stimulus occurs at attended location
•Miscued (invalid) trial: stimulus occurs at other location (with low probability)
-Neutral: the cue does not provide information •Baseline to compare valid and invalid

Question 17

Attentional Costs and Benefits
Posner, Nissen, & Ogden (1978) result

Answer 17

Faster RT with valid cue
Slower RT with invalid cued
The exp is Very flexible: can be used with RT or accuracy, and to compare all kinds of stimuli

Question 18

Causes of Cuing Effects

Answer 18

These costs and benefits may be due to switching time (the time needed to move/orient the attentional spotlight) – the cost of disengaging from the wrong location, and benefit from engaging at the correct location before the stimulus.
However, they may also be due to unequal capacity allocation – reaction time depends on attentional capacity allocated to location. For a neutral cue capacity is spread across locations, but for a focused cue capacity is concentrated on one location.
It is hard to test between these two alternatives

Question 19

Evidence for Separate Orienting Systems Cuing effect

Answer 19

Different time course of central and peripheral cuing
Peripheral effect peaks rapidly, central effect peaks slowly due to needing cognitive processing

Question 20

Evidence for Separate Orienting Systems, II Different effects of load

Answer 20

Voluntary orienting slowed by memory load; reflexive orienting is not. as some cognition process is used up
Consistent with different capacity demands of two systems

Question 21

Evidence for Separate Orienting Systems, III long SOA reverse

Answer 21

-At long SOA, people take longer to react in trial
Found only with peripheral cues, not with central cues
-after paying attention and nothing happen, it cause to pay less attention

Question 22

What’s the Purpose of Inhibition of Return IRL

Answer 22

Ecological argument: Allows efficient search of complex environment.
Prevents repeated search of same location. Don’t need to maintain a “mental map” of locations that have been searched