Attention - Structural & Capacity Theories

Question 1

what were the 3 conditions in moray’s 1970 experiment on the cost of divided attention?

Answer 1

1. selective (attend to one channel, louder beep could occur on either channel but not simultaneously)
2. Exclusive OR ( attend to both channels louder beep could occur on either channel but not simultaneously)
3. Inclusive OR (Attend to both channels, louder beep could occur on either channel simultaneously and separately)

Question 2

what results did moray get from his study on cost of divided attention?

Answer 2

Selective - 67%
Exclusive OR - 54%
Inclusive OR - 54% (OR) 31% (AND)
Thus, 1. moderate cost of divided attention (OR < SEL)
2. large cost of simultaneous detection (AND < OR)

Question 3

why does late selection support AND < OR?

Answer 3

because two simultaneous targets will both be selected by pertinence and will compete to get through the filter, hence there is a cost for when the beep is delivered at the same time

Question 4

why does late selection not provide support for OR < SEL?

Answer 4

because if there aren’t two targets competing at the same time, there is no competition so there shouldn’t be any cost between switching between two attended channels

Question 5

why does early selection theory support OR < SEL?

Answer 5

because it predicts that both channels are attenuated when your attention is divided, hence a diminished response for dual channels compared to attending single channel hence poorer than if you were just focussing attention

Question 6

why does early selection not provide support for AND < OR?

Answer 6

because attenuation shouldn’t depend on identity of stimulus

Question 7

summarise moray’s support or lack of for late v early selection

Answer 7

AND < OR: 
Early: not supported 
Late: supported 
OR < SEL 
Early: supported 
Late: Not supported

Question 8

what are the two overarching theories as to why we experience attentional limits? provide summary of its views

Answer 8

1. structural (pre 1970)
   - bottle neck, can only deal with one stimulus at a time
2. capacity (post 1970)
   - information processing is mental work, work requires activation of neural structure and there is a limited capacity to activate structure

Question 9

what is the main idea behind capacity theories as opposed to structural theories?

Answer 9

that dividing attention (capacity) is a top down process and extremely flexible… and that a lot rides on the the mental effort required for each task

Question 10

what is graceful degradtion?

Answer 10

theory that performance degrades as available capacity is reduced… the theoretical graph of dividing attention between two tasks, eg 100:0, 80:20, 50:50, 20:80, 0:100

Question 11

what did bonnel and hafter investigate and find re capacity theory?

Answer 11

had participants shift their attention between two different tasks and found that for easier tasks (detection of light or auditory tone) there was no real trade off, but for difficult tasks (discrimination of increases/decreases in intensity) there was the curved line trade of

Question 12

pros and cons of capacity theory

Answer 12

pro:

• led to new experiments
  cons:
• vagueness

Question 13

what is attentional orienting?

Answer 13

shifts in eye movements that give insights to attention

Question 14

how does spatial cuing paradigm work roughly?

Answer 14

attract attention to area A, present stimulus to A or B and then compare performance

Question 15

what is stimulus onset asynchrony (SOA)?

Answer 15

the time between the cue and the delivering of the stimulus

Question 16

what are the proposed causes of cuing effects (costs and benefits)?

Answer 16

1. switching time - the time to move the spotlight
2. unequal capacity allocation - when focused, capacity is concentrated on one location, for neutral it is spread across both

Question 17

what are the two attentional control systems (orienting systems)

Answer 17

1. endogenous (voluntary) - cognitive, need to interpret

2. exogenous (reflexive) - direct/spatial, no need to interpret

Question 18

describe the two different cues

Answer 18

arrow: central, symbolic - we have to learn what an arrow means
flash of square colour: peripheral, spatial cue, just a response, don’t need to learn what the flash “means”

Question 19

what are the characteristics of central cues?

Answer 19

Central - cuing effect becomes larger the longer the time of SOA until 300ms, then peaks and stays here as this is essentially talking about the time it takes to semantically encode this info (top down)

Question 20

how do you measure cuing effect?

Answer 20

measuring the time of attentional shifts

mean response time (invalid) minus mean response time (valid)

Question 21

what are the characteristics of peripheral cues?

Answer 21

peripheral - cuing effect peaks at 150 ms on the SOA, but this is transient, and if the SOA is increased, cuing effect begins to decline

Question 22

what are the 3 ways in which support was found for the exogenous reflexive system or the endogenous voluntary systems?

Answer 22

1. effects of SOA and cue type: reflexive is faster, transient… while voluntary is slower, more sustained
2. jonides - retaining digits (memory load) slowed voluntary but not reflexive orienting - voluntary under more cog control
3. inhibition of return - for reflexive but not inhibitory

Question 23

what is inhibition or return?

Answer 23

that if the SOA on peripheral tasks was extended out to 300ms, then this actually slowed reaction time in responding to the stimulus, theory here is that its harder to get the attention back to where it appeared that nothing interest was there - only found with peripheral cues

Question 24

what is the proposed purpose of inhibition of return ?

Answer 24

• ecological argument - allows efficient search of complex environment
• prevents repeated search of same location