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Bilingualism and Cognitive Development: Evidence for Changes in Attentional Control
Ellen BialystokYork University
Language Representation in Bilinguals
L1
L1
L1
L1
L1
L1
L1
L1
L2
L2
L2
L2
L2
L2 L2
L2
L2
L2
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L2
L2
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L2
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L1
L1
L1
L1
L1
L1
L1
L1Attend
IgnoreAttend
Ignore
Switch
ExecutiveControl
ExecutiveControlAdvantages
Development of Executive Processes
• Last area of brain (frontal lobes) to mature• Last cognitive skills to develop in
childhood, first to decline with aging• Children typically develop control over
attention and inhibition at about 5 years• Experience in managing two languages
may promote this development
1. Perceptual Organization and Meaning
• Embedded Figures Test is test of field-dependence/field-independence and a measure of intelligence
• Compare to misleading context of ambiguous figures
• Participants – 5 ½ years olds27 Monolinguals26 Bilinguals
Children’s Embedded Figures Test
• Perceptual analysis of complex figure to find simple component
• Requires inhibition of overall perceptual configuration and interpretation of parts
• Items divided into tent (triangle) and house shapes
• Score is total of two sections
Embedded Figures Test: Tent
Embedded Figures Test: House
Embedded Figures TaskBialystok & Shapero, 2005
0
2
4
6
8
10
12
14
Tent House
Item Type
Mea
n N
umbe
r C
orre
ct
MonolingualBilingual
Ambiguous Figure Reversals
• Ability to see an alternative interpretation of an ambiguous figure develops at around 6 years
• Need to assign new interpretation to perceptual stimulus inhibit previous interpretation?
• Create a graduated scale for degree of ability
Ambiguous Images
Content Figure-Ground
Scoring System
• 5: Spontaneous identification• 4: Identify one feature• 3: Identify second feature• 2: Name alternative image• 1: Disambiguated image of
alternative • 0: No idea!
Criterion: Child indicates two features of alternative image
Points
Disambiguated Images (1 point)
“man” “rat”
Reversibility ScoresBialystok & Shapero, 2005
00.5
11.5
22.5
33.5
44.5
5
rat/man duck/rabbit vase/face sax/woman
Mea
n Sc
ore
MonolingualBilingual
** *
ContentFigure-Ground
Embedded Figures vs Reversible Figures
• EFT requires pattern analysis to find the hidden component. There is no conflict.
• Ambiguous figures requires re-assigning a meaning that conflicts with the current interpretation. It must stop being “a duck” for the image to reverse.
• Effect of bilingualism is in processing conflict
2. Dimension Change Card Sort Task
• Bidimensional stimuli sorted by one dimension, then other
• Young children fail to switch second time
• Perceptual: colour-shape• Conceptual: function-
location
Shape-Colour
Bialystok, 1999: N=60, 4 ½ yrsBialystok & Martin, 2004: Study 1 N=67,6 yrs; Study 3 N=51, 5 ½ yrs
Function-Location
Post-Switch Scores in DCCSBialystok, 1999; Bialystok & Martin, 2004
Perceptual Stimuli:Colour-Shape
0123456789
10
B&M,2004,1 B&M,2004,3
Monolingual Bilingual
Conceptual Stimuli:Function-Location
0123456789
10
B,1999 B&M,2004
Monolingual Bilingual
* *
Perceptual vs. Conceptual Stimuli
• Perceptual feature salient – represented “round one”; Re-represent “yellow one”
• Conflict between representations (cf. Ambiguous Figures)
• Function-location stimuli have no perceptual conflict – stimulus interpreted individually (cf. Embedded Figures)
• Bilingual advantage for resolving perceptual conflict
3. Simon Effect
• Prepotent response to position cues• Stimuli contain target and (irrelevant)
position cuesPosition consistent with R congruentPosition conflicts with R incongruent
• Simon effect (SE) is RT cost for incongruent trials
• Conflict resolution should be easier for bilinguals, so smaller SE
Rule: red square left green square right
RL
Simon EffectRule: red square left green square right
Congruent
Incongruent
SE = Incongruent - Congruent
RL
Simon Task by Language for ChildrenMartin & Bialystok, submitted
200
400
600
800
1000
1200
1400
1600
1800
Congruent Incongruent Simon Effect
Mea
n R
T m
s
MonolingualBilingual
N=344 ½ year olds
* *
*
Adults and Aging: Simon TaskBialystok, Craik, Klein, & Viswanathan, 2004
• 94 participants between 30 and 80 years• Half bilingual matched by age• Background measures of working memory,
language proficiency, intelligence (Cattell)
ControlRule: red square left green square right
RL
Mean RT for Control by Decade
0150300450600750900
1050120013501500
30-39 40-49 50-59 60-69 70-79
Age
Mea
n R
T (m
s)
Monolingual Bilingual
Simon EffectRule: red square left green square right
RL
Mean Simon Effect by Decade
0100200300400500600700800900
1000
30-39 40-49 50-59 60-69 70-79
Age
RT
Diff
eren
ce (m
s)
Monolingual Bilingual
4. Stroop Task
• Prototypical task for frontal executive processing
• Bilingual Stroop effect: SE across languages = SE within languages
• (Almost) no research examining SE within a language comparing conflict resolution for monolinguals and bilinguals
• Bilinguals should resolve conflict more easily and show a smaller SE
Sample
• 96 participants: 24 young monolinguals, 21 years24 young bilinguals, 20 years24 older monolinguals, 67 years24 older bilinguals, 68 years
• Bilinguals fully balanced lifelong bilinguals• Variety of language pairs
Stroop Task
XXX
RED BLUE
RED
Experimental
Congruent
Incongruent
ControlStroop Effect
Colour
Word
Correct answer: “Red”
Stroop Control Conditions
XXX
RED
Control
Colour200
300
400
500
600
700
800
Colour
Young:Mono Young:BiOld:Mono Old:Bi
Age: n.s.Lang: F < 1
200
300
400
500
600
700
800
Word
Young:Mono Young:BiOld:Mono Old:Bi
Age: n.s.Lang: F < 1Word
Stroop Effect by Group
100
150
200
250
300
350
Stroop Effect
Mea
n D
iff R
T (In
cong
- C
ong)
Young MonoYoung BilingOld MonoOld Biling
Language Representation in Bilinguals
L1
L1
L1
L1
L1
L1
L1
L1
L2
L2
L2
L2
L2
L2 L2
L2
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L1
L1
L1
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L1
L1
L1
L1Attend
IgnoreExecutiveControl
Switch
Lexical Conflict
Lexical Retrieval Deficits
ExecutiveControlAdvantages
Bilingualism and Lexical Access
• Control advantages and EF processing differences come from linguistic conflict
• Need to resolve linguistic conflict beneficial to these processes
• But the problem of linguistic conflict remains
• Are there group differences in lexical access?
Receptive Vocabulary
• PPVT scores as rough vocabulary size
• Frequent reports of bilingual deficits
• Combined data: N=5285 yrs: N=976 yrs: N=3417 yrs: N=568 yrs: N=34 80
859095
100105110115120
5 6 7 8
Monolingual Bilingual
* * *
Lexical Retrieval
0102030
40506070
Boston Fluency
Young:Mono Young:BiOld:Mono Old:Bi
* ** *
• Younger & older adults (from Stroop), N=96
• Boston Picture Naming
• Letter and category fluency“F” “A” “S” “Animals”
Bilingual Effects on Cognition
L1
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L1
L1L1
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L2 L2
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Lexical Conflict
CognitiveControlAdvantages
Lexical Retrieval Deficits
Summary of Bilingual EffectsAdvantages to executive function• Control of attention
Simon task, Stroop task• Switching
Embedded figures, DCCSDisadvantages to lexical retrieval• Vocabulary
PPVT• Fluency
Fluency and Boston Naming
Credits
• Fergus Craik• Ray Klein• Gigi Luk• Michelle Martin• Jeni Pathman• Dana Shapero• Mythili Viswanathan
Funding