WM 3 - training effects

Question 1

brain training

Answer 1

• does it work?
• aim is to make brain bigger and stronger
• can use apps to help
  –> but do they?

Question 2

The N back task

Answer 2

• brain training task
• test of working memory
• remember the list of letters
  –> is the presented letter the same as the letter two letters before
  –> e.g. A J L = no
  –> e.g. F H F = yes

Question 3

Ericcson et al (1980) study

Answer 3

• after more than 230 hours of practice in the laboratory, a subject was able to increase his memory span from 7 to 79 digits
• with an appropriate mnemonic system, there is seemingly no limit to memory performance with practice

Question 4

define transfer

Answer 4

improvements in a practiced task leads to improvements in unpracticed tasks

Question 5

was the task specific in Ericcson’s et al (1980) study?

Answer 5

• in one experimental session, S.F. was switched from digits to letters of the alphabet after 3 months of practice and exhibited no transfer
• his memory span dropped back to about six consonants

Question 6

strategy based training

Answer 6

• introduction and acquisition of strategies
  –> e.g. a pneumonic to remember the name and order of planets
• helpful for material-or-task specific tasks
• difficult to transfer to other contexts

Question 7

process based training

Answer 7

• repeated practice of specific tasks targeting cognitive processes
  –> e.g. daily practice of complex span tasks
• assumed to transfer to other contexts

Question 8

functional overlap between training and transfer

Answer 8

transfer is expected if practiced and non-practiced tasks share underlying processes

Question 9

working memory as a core ability

Answer 9

• variation in working memory is correlated with variation in many other abilities
• by enhancing working memory, we might be able to improve a wide range of related cognitive abilities

Question 10

success between training and transfer

Answer 10

• practise = working memory training tasks (N-back)
• near transfer = untrained working memory tasks (complex-span task)
• far transfer = different (but related) cognitive ability (e.g. reasoning)

Question 11

how do we measure training effects?

Answer 11

• methodological rationale
• performance at a pretest (baseline) assessment is compared to performance at a post-test after training
  –> e.g. you do all tasks (practise, near and far) before training, one task during training (practise) and then all tasks again post-test

Question 12

how do we compare results in a methodological rationale?

Answer 12

• change is evaluated relative to a control group
  –> passive group = no intervention
  –> active group = alternative intervention

Question 13

evaluate use of passive control groups

Answer 13

• appropriate to control for:
  –> test-retest effect (improved performance with familiarity - better in test 2)
• not appropriate to control for:
  –> other factors that affected the period in between test and retest (e.g. motivation) because they don’t have the in between period
  –> placebo effect as no training is done so the believed benefits of training aren’t present

Question 14

evaluate the use of active control groups

Answer 14

• appropriate to control for:
  –>other factors that affected the period in between test and retest (e.g. motivation)
  –> placebo effect

Question 15

Klingberg et al (2002) - seminal trainign study

Answer 15

• can intensive working memory training help children with attention deficits such as in ADHD?
• computerised training program with a variety of working memory tasks
• tested improvements relative to an active control group in the trained and in untrained tasks
• did training and transfer tasks

Question 16

what was the design of Klingberg et al (2002)?

Answer 16

• pre test
• experimental group did training 5x a day (high dose)
• active control group did training 1x a day (low dose)
  –> trained for 5 weeks
• post-tests measured the change in the training and transfer tasks

Question 17

results of Klingberg et al (2002)

Answer 17

• all groups got better at training and transfer tasks
• high dose see greater improvement in training scores than low dose
• high dose also see greater improvement in transfer task compared to low dose

Question 18

evaluate Klingberg et al (2002)

Answer 18

• first evidence for training and transfer effects, but very small group sizes (n = 7)

Question 19

Klingberg et al (2005) - seminal training studies 2

Answer 19

• multicentre, randomised controlled trial (N = 53)
• pre test
• 5 weeks training
  –> adaptive training (experimental group)
  –> non-adaptive training (control group)
• post test
  –> measure training and transfer performance
• then a follow up after 3 months
  –> change in training and transfer measured again

Question 20

adaptive and non-adaptive training in Klingberg et al (2005)

Answer 20

• adaptive training = change in difficulty
  –> the difficulty increases as you get better
• non-adaptive training = same difficulty level
  –> stay at the lowest level of difficulty

Question 21

results of Klingberg et al (2005)

Answer 21

• training tasks:
  –> larger benefits in adaptive relative to non-adaptive WM training group in the practiced tasks
• transfer tasks
  –> larger benefits in adaptive relative to non-adaptive WM training group in unpracticed inhibition and reasoning tasks

Question 22

evaluate Klingberg et al (2005)

Answer 22

• scores in the write up were corrected for differences in baseline score
• evidence for training and transfer effects of working memory training
• however, although corrected differences are significant, uncorrected group differences in change are only small

Question 23

Jaeggi et al (2008) - seminal training studies 3

Answer 23

• pre test
• training
  –> working memory training vs passive control (no intervention)
• post-test
  –> measure change in training and transfer task performance

Question 24

methods in Jaeggi et al (2008)

Answer 24

• experimental group did Dual n-back training –> n back + auditory stimuli
• the transfer task was a reasoning task (Raven’s task)

Question 25

results of Jaeggi et al (2008)

Answer 25

training group better at training and transfer tasks in post-test compared to passive control

Question 26

Redick et al (2013)

Answer 26

• pre test
• then 10 sessions of working memory training vs active control (visual search task, something but not WM) vs passive control
• then did a mid-test
• then did another 10 sessions (same as before)
• then did a post-test
  –> measure change in training and transfer task performance

Question 27

results of Redick et al (2012)

Answer 27

• no significant near transfer effects
• no significant far transfer effects (spatial reasoning and verbal reasoning)

Question 28

the hype of working memory training

Answer 28

• training studies published 2002-2015
• hype and inconsistencies led to highly active field of research

Question 29

does working memory work?

Answer 29

• inconsistent evidence across a large number of studies
• how can these inconsistencies be explained?

Question 30

reasons for inconsistencies (methodological issues)

Answer 30

• lack of active controls
  –> placebo effects
• single tasks used for measuring cognitive abilities
  –> task-impurity problem
• small sample sizes
  –> low statistical power and imprecise measurement

Question 31

reasons for inconsistencies (theoretical issues)

Answer 31

• many studies lack theoretical framework of training and transfer
• without theory explaining mechanisms of transfer (i.e. why we expect effects) we can’t predict when we should observe effects

Question 32

multiple sources of variance framework (mechanisms of transfer)

Answer 32

• intervention specific factors
  –> impacts training and transfer
• individual differences
  –> impacts training and transfer
• training impacts transfer
• transfer effects our observed effects

Question 33

two proposed mechanisms of transfer

Answer 33

1. enhanced capacity
2. enhanced efficiency

Question 34

enhanced capacity

Answer 34

• training increases the number of information elements held in working memory (i.e. larger broad focus of attention)
• prediction:
  –> training leads to BROAD transfer effects

Question 35

enhanced efficiency

Answer 35

• training supports a more efficient use of the existing capacity through strategies or faster processing
• prediction:
  –> training leads to SELECTIVE transfer effects

Question 36

De Simoni & von Bastian (2018) - mechanisms of transfer study

Answer 36

• pre test
• training for 20 sessions
  –> WM binding
  vs
  –> WM updating
  vs
  –> active control (visual search)
• then a post-test

Question 37

the training in De Simoni & Von Bastian (2018)

Answer 37

• N = 197 young adults
• randomly assigned
• double-blind
• 4 tasks per intervention

Question 38

the pre-post change in De Simoni & Von Bastian (2018)

Answer 38

• 4 tasks per ability
• trained abilities
• near transfer
• far transfer

Question 39

results/conclusions of De Simoni & Von Bastian (2018))

Answer 39

• large improvements in the trained tasks
• no evidence for near transfer
• no evidence for far transfer
• training improved neither WM capacity nor efficiency
• BUT:
  –> might be different for other WM tasks or measures of specific types of efficiency

Question 40

training progress

Answer 40

• large individual differences in training progress
• in a complex span task there is often increasingly large individual differences

Question 40

who benefits the most from training? (3 hypotheses)

Answer 40

1. magnification
   –> people with higher ability gain more
2. compensation
   –> people with lower ability gain more
3. no difference

Question 41

Guye et al (2017) study

Answer 41

• how are initial training performance and slope in training progress related?
• younger adults showed magnification of initial task performance
• little effect in older adults

Question 42

intervention specific factors

Answer 42

• do training and transfer effects depend on the type of training task?
• do training and transfer effects depend on the dose of the intervention?

Question 43

Melby-Lervag et al (2016) - meta analysis

Answer 43

• does effectiveness depend on the type of training task?
• N-back vs Cogmed vs complex span task
• On average, Cogmed induces relatively larger verbal near transfer, but n-back yields relatively larger far transfer

Question 44

Melby-Lervag et al (2016) - meta analysis (dose)

Answer 44

• Does effectiveness depend on training dose?
• small vs large
• training dose has little effect
  –> the only significant difference occurs for far transfer but in the opposite direction
  –> i.e. small dose does better than large dose
• type of training and dose have very small effects

Question 45

individual differences

Answer 45

Possible factors:
- age
- gender
- personality
- motivation
- beliefs

Question 46

Guye et al (2017) individual difference study

Answer 46

• how are demographics, personality, motivation, and beliefs related to the slope in training progress?
• limited evidence for individual differences predicting slope in training progress
• however, results may differ for samples with successful training and transfer

Question 47

Is working memory training effective?

Answer 47

• training produces large improvements in the trained tasks but rarely transfer
• transfer effects, if existing, are small and volatile
• we can rule out a range of potential moderators but we still don’t know why training “works” better in some studies than others

Question 48

the take home message

Answer 48

• enhancing WM could improve a range of other, functionally overlapping abilities
• transfer may occur through enhancing capacity or efficiency
• seminal training studies reported far transfer, but these findings are difficult to replicate
• multiple sources of variance may contribute to these inconsistent results
• don’t take results by their face value – critically assess the methodological quality