McNab and Klingberg study 2008

Question 1

what is the basis of the research

Answer 1

cognitive stability

Question 2

what is a distractor

Answer 2

stimulus that diverts attention away from target item that pp is trying to focus on

Question 3

what was the task

Answer 3

a visual spatial working memory task in an MRI scanner

Question 4

what are the 2 conditions

Answer 4

distractor and no distractor

Question 5

procedure no distraction

Answer 5

-pp shown geometric shape, triangle indicates distraction trial, square = no distraction trial
-pp then viewed 16 boxes in circular pattern, some filled with red colour, others empty
-stimuli disappeared and pp had to remember positioning of red squares after delay (load 3 or 5)
-then test phase, question mark in boxes and pp answer yes when it was a box occupied by red square

Question 6

procedure distraction cond

Answer 6

-pp viewed 3 red dots and 2 yellow
-pp supposed to maintain position of only red dots
-load 3 (+2 distractors)
-pp should allow red dots to enter WM not yellow dots

Question 7

what is the subtraction method

Answer 7

-technique for estimating duration of psychological process by measuring RT for task with the psychological process and without the psychological process

Question 8

what is load

Answer 8

the amount of info the WM can hold at 1 time

Question 9

what was the accuracy of the tasks

Answer 9

no distraction load 3: 85%
distraction: 80%

subtract no distraction 3 from distraction cond to see the effect of the 2 distractors

Question 10

what is preparatory filtering activity

Answer 10

diff between brain activity during instruction period of distractor task and brain activity during the distractor period of no distractor task

Question 11

what were the preparatory filtering activity findings

Answer 11

(observed before pp engaged in distractor filtering activity)
-3 brain regions show preparatory filtering activities:
1.middle frontal gyrus
2.L lobus pallidus
3. L putamen
brain regions involved in forth coming distractor filtering event

Question 12

what are the findings related to load

Answer 12

-when comparing no distractor task load 3 and 5, it was found there was load sensitive activity in R posterior parietal cortex
-so this region is sensitive to load

Question 13

what happens if we are unable to filter out distractions

Answer 13

distractor info enters WM and consumes capacity of WM so in distractor task we see more activity in parietal cortex bc the pp additionally store distractors when not needed

Question 14

if you can filter out distractors…

Answer 14

there will be no difference in load sensitive parietal region (distractors will not enter the WM)

Question 15

comparison of brain activity in no distractor load 3 and distractor task during encoding and maintenance…

Answer 15

-correlated load sensitive parietal activity with preparatory filtering activity
-sig results found in L globus pallidus (neg correlation)
-pp lower preparatory filtering activity in L globus pallidus had higher load sensitive activity in R posterior parietal cortex
-suggests globus pallidus activity may exert attentional control over access to WM storage in parietal cortex

Question 16

what else did pp perform

Answer 16

WM capacity task outside the study
-measures how much info can be stored in WM
-found globus pallidus activity was pos related to WM capacity
-pp with high preparatory filtering activity also had high WM capacity
-maybe bc pp better at filtering out distractor info from entering load sensitive parietal region

Question 17

what is the main finding

Answer 17

-frontal and basal ganglia activity exert attentional control over access to WM storage in parietal cortex and helps explain indiv differences in WM capacity