When high-capacity readers slow down andlow-capacity readers speed up: Working memory
differences in unbounded dependencies forGerman and Spanish readers
Bruno Nicenboim, Pavel Logacev,Carolina Gattei and Shravan Vasishth
University of Potsdam
1 / 24
Aim:
I examine whether the increase of distance in unboundeddependencies is associated with slower reading times (localityeffects) once several confounds are controlled
I examine whether locality effects are modulated by workingmemory capacity
I examine whether the results hold for SVO and SOV structures
2 / 24
Unbounded dependencies
(1) Someone asked what Mary didx last summer.
(2) Someone asked what Mary [some words] didx last summer.
3 / 24
Unbounded dependencies
(1) Someone asked what Mary didx last summer.
(3) Someone asked what Mary, the girl that we met at school, didx last
summer.
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Unbounded dependencies
(1) Someone asked what Mary didx last summer.
(4) Someone asked what Mary’s sister didx last summer.
3 / 24
Unbounded dependencies
(1) Someone asked what Mary didx last summer.
(2) Someone asked what Mary [some words] didx last summer.
3 / 24
Memory-based explanations
I Dependency Locality Theory (DLT) (Gibson, 2000)
I Activation-based account (Lewis & Vasishth, 2005)
4 / 24
Memory-based explanations: DLT
Processing costs in DLT (Gibson, 2000)
I Integration costs: based on the distance between dependentand head
I Storage costs: based on the number of heads required tocomplete the current input as grammatical
5 / 24
Memory-based explanations - Activation-based account
Retrieval costs in the activation-based account (Lewis & Vasishth,
2005)
I Decay: more time has passed from the encoding of anargument
I Similarity-based interference: other items with similarfeatures serve as distractors
6 / 24
Memory-based explanations
(1) Someone asked what Mary didx last summer.
(2) Someone asked what Mary [some words] didx last summer.
Prediction of processing difficulty at “did”:
Higher processing difficulty in (2) than in (1)
Can we translate costs to RTs?
RTs at “did” should also be:Longer reading times in (2) than in (1)
7 / 24
Memory-based explanations
(1) Someone asked what Mary didx last summer.
(2) Someone asked what Mary [some words] didx last summer.
Prediction of processing difficulty at “did”:
Higher processing difficulty in (2) than in (1)
Can we translate costs to RTs?
RTs at “did” should also be:Longer reading times in (2) than in (1)
7 / 24
Memory-based explanations
(1) Someone asked what Mary didx last summer.
(2) Someone asked what Mary [some words] didx last summer.
Prediction of processing difficulty at “did”:
Higher processing difficulty in (2) than in (1)
Can we translate costs to RTs?
RTs at “did” should also be:Longer reading times in (2) than in (1)
7 / 24
Memory-based explanations
(1) Someone asked what Mary didx last summer.
(2) Someone asked what Mary [some words] didx last summer.
Prediction of processing difficulty at “did”:
Higher processing difficulty in (2) than in (1)
Can we translate costs to RTs?If so, we have locality effects.
RTs at “did” should also be:Longer reading times in (2) than in (1)
7 / 24
Memory-based explanations
(1) Someone asked what Mary didx last summer.
(2) Someone asked what Mary [some words] didx last summer.
Prediction of processing difficulty at “did”:
Higher processing difficulty in (2) than in (1)
Can we translate costs to RTs?If so, we have locality effects.
RTs at “did” should also be:Longer reading times in (2) than in (1)
7 / 24
Differential effects for different WMC
I low-WMC readers have more difficulty especially with complexsentences in comparison to high-WMC ones
I for garden-path vs. non-garden path sentences: Christianson,
Williams, Zacks, and Ferreira (2006)
I for comprehension reaction times in subject- vs. object-relativeclauses: King and Just (1991), Vos, Gunter, Schriefers, and Friederici
(2001)
I WMC influences the probabilities of success in integratinginformation over a distance in a text (Daneman & Carpenter, 1980)
I WMC is associated with the ability to maintain on-taskthoughts (McVay & Kane, 2011)
8 / 24
Differential effects for different WMC
I low-WMC readers have more difficulty especially with complexsentences in comparison to high-WMC ones
I for garden-path vs. non-garden path sentences: Christianson
et al. (2006)
I for comprehension reaction times in subject- vs. object-relativeclauses: King and Just (1991), Vos et al. (2001)
I WMC influences the probabilities of success in integratinginformation over a distance in a text (Daneman & Carpenter, 1980)
I WMC is associated with the ability to maintain on-taskthoughts (McVay & Kane, 2011)
8 / 24
Differential effects for different WMC
I low-WMC readers have more difficulty especially with complexsentences in comparison to high-WMC ones
I for garden-path vs. non-garden path sentences: Christianson
et al. (2006)
I for comprehension reaction times in subject- vs. object-relativeclauses: King and Just (1991), Vos et al. (2001)
I WMC influences the probabilities of success in integratinginformation over a distance in a text (Daneman & Carpenter, 1980)
I WMC is associated with the ability to maintain on-taskthoughts (McVay & Kane, 2011)
8 / 24
Problems
(5) a. Someone asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I
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Problems
(6) a. Someone [some words] asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I
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Problems
(6) a. Someone [some words] asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I Systematic change of the structure of the sentence:I
I
I
I
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Problems
(6) a. Someone [some words] asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I Systematic change of the structure of the sentence:I Increasing the distance also increases the expectations for the
head (Antilocality effects!) (Levy, 2008; Hale, 2001)I
I
I
9 / 24
Problems
(7) a. A Someone [some words] asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I Systematic change of the structure of the sentence:I Increasing the distance also increases the expectations for the
head (Antilocality effects!) (Levy, 2008; Hale, 2001)I Facilitation at the verb due to preactivation (Vasishth, 2003)I
I
9 / 24
Problems
(8) a. Someone [some words] asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I Systematic change of the structure of the sentence:I Increasing the distance also increases the expectations for the
head (Antilocality effects!) (Levy, 2008; Hale, 2001)I Facilitation at the verb due to preactivation (Vasishth, 2003)I Encoding interferenceI
9 / 24
Problems
(8) a. Someone [some words] asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I Systematic change of the structure of the sentence:I Increasing the distance also increases the expectations for the
head (Antilocality effects!) (Levy, 2008; Hale, 2001)I Facilitation at the verb due to preactivation (Vasishth, 2003)I Encoding interferenceI Encoding ”facilitation” (Hofmeister, 2007)
9 / 24
Problems
(9) a. Someone [some words] asked what Mary didx last summer.
b. Someone asked what Mary [some words] didx last summer.
c. Someone [some words] asked if Mary did something last summer.
d. Someone asked if Mary [some words] did something last summer.
Potential Confounds:
I Word position effects (Ferreira & Henderson, 1993)
I Systematic change of the structure of the sentence:I Increasing the distance also increases the expectations for the
head (Antilocality effects!) (Levy, 2008; Hale, 2001)
I Facilitation at the verb due to preactivation (Vasishth, 2003)
I Encoding interferenceI Encoding ”facilitation” (Hofmeister, 2007)
9 / 24
Predictions
10 / 24
Predictions
10 / 24
Predictions
10 / 24
Predictions
10 / 24
Aim:
I examine whether the increase of distance in unboundeddependencies is associated with slower reading times (localityeffects) once several confounds are controlled
I examine whether locality effects are modulated by workingmemory capacity
I examine whether the results hold for SVO and SOV structures
11 / 24
Self-paced reading in Spanish (Argentina) and German(Germany)
Experiment 1 - Spanish Self-paced reading
I operation span task for working memory capacity (WMC)
I rapid automatized naming for reading skill (RS)
I self-paced reading task on 48 items with 4 conditions
I subjects: 79
Experiment 2 - German Self-paced reading
I operation span task
I rapid automatized naming
I self-paced reading task on 48 items with 4 conditions
I subjects: 72
12 / 24
(10) a. short unbounded dependency
LaThe
hermanasister
menoryounger
deof
SofıaSofia
preguntoasked
a quienwho.ACC
fuewas
quethat
MarıaMarıa
habıa saludadohad greeted
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
b. long unbounded dependency
SofıaSofia
preguntoasked
a quienwho.ACC
fuewas
quethat
la hermana menor de Marıathe sister younger of Marıa
habıa saludadohad greeted
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
c. short baseline
LaThe
hermanasister
menoryoungerr
deof
SofıaSofia
preguntoasked
siif
MarıaMaria
habıa saludadohad greeted
ato
lathe
primacousin
deof
PaulaPaula
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
d. long baseline
SofıaSofia
preguntoasked
siif
la hermana menor de Marıathe sister younger of Maria
habıa saludadohad greeted
ato
lathe
primacousin
deof
PaulaPaula
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
13 / 24
(10) a. short unbounded dependency
LaThe
hermanasister
menoryounger
deof
SofıaSofia
preguntoasked
a quienwho.ACC
fuewas
quethat
MarıaMarıa
habıa saludadohad greeted
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
b. long unbounded dependency
SofıaSofia
preguntoasked
a quienwho.ACC
fuewas
quethat
la hermana menor de Marıathe sister younger of Marıa
habıa saludadohad greeted
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
c. short baseline
LaThe
hermanasister
menoryoungerr
deof
SofıaSofia
preguntoasked
siif
MarıaMaria
habıa saludadohad greeted
ato
lathe
primacousin
deof
PaulaPaula
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
d. long baseline
SofıaSofia
preguntoasked
siif
la hermana menor de Marıathe sister younger of Maria
habıa saludadohad greeted
ato
lathe
primacousin
deof
PaulaPaula
enat
lathe
puertadoor
delof the
colegioschool
ayeryesterday
aat
lathe
tarde.afternoon
13 / 24
(11) ......
preguntoasked
{a quien{who.ACC
fuewas
que;that;
si}if}
(la(the
hermanayounger
menorsister
de)of)
|||
MarıaMarıaprecritical
|||
habıahadcritical 1
|||
saludadogreetedcritical 2
|||
{a; en}{to; in}spillover 1
|||
lathespillover 2
|||
...
...
14 / 24
Results for Spanish SPR
15 / 24
Results for Spanish SPRLocality effects + Locality effects x WMC
15 / 24
Results for Spanish SPRLocality effects + Locality effects x WMC
15 / 24
(12) a. short unbounded dependency
MariasMary’s
außerstextremely
kaltschnauzigeuncaring
Lehrerinteacher
fragte,asked
wenwho.ACC
die Mutterthe mother
gesternyesterday
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
b. long unbounded dependency
DieThe
Lehrerinteacher
fragte,asked
wenwho.ACC
Marias außerst kaltschnauzige Mutter
Mary’s extremely uncaring mother
gesternyesterday
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
c. short baseline
MariasMary’s
außerstextremely
kaltschnauzigeuncaring
Lehrerinteacher
fragte,asked
obif
die Mutterthe mother
jemandensomeone.ACC
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
d. long baseline
DieThe
Lehrerinteacher
fragte,asked
obif
Marias außerst kaltschnauzige Mutter
Mary’s extremely uncaring mother
jemandensomeone
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
16 / 24
(12) a. short unbounded dependency
MariasMary’s
außerstextremely
kaltschnauzigeuncaring
Lehrerinteacher
fragte,asked
wenwho.ACC
die Mutterthe mother
gesternyesterday
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
b. long unbounded dependency
DieThe
Lehrerinteacher
fragte,asked
wenwho.ACC
Marias außerst kaltschnauzige Mutter
Mary’s extremely uncaring mother
gesternyesterday
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
c. short baseline
MariasMary’s
außerstextremely
kaltschnauzigeuncaring
Lehrerinteacher
fragte,asked
obif
die Mutterthe mother
jemandensomeone.ACC
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
d. long baseline
DieThe
Lehrerinteacher
fragte,asked
obif
Marias außerst kaltschnauzige Mutter
Mary’s extremely uncaring mother
jemandensomeone
beimat.the
Treffenmeeting
angeschrien hatyelled had
mitwith
schrillershrill
Stimme.voice
16 / 24
Results for German SPR
17 / 24
Results for German SPRLocality effects + Locality effects x WMC
17 / 24
Results for German SPRLocality effects + Locality effects x WMC
17 / 24
General results
I WMC affects retrieval times at unbounded dependencyresolution
I but high-WMC readers showed the strongest slow-down
I and low-WMC readers showed a speed-up
18 / 24
General results
I WMC affects retrieval times at unbounded dependencyresolution
I but high-WMC readers showed the strongest slow-down
I and low-WMC readers showed a speed-up
18 / 24
General results
I WMC affects retrieval times at unbounded dependencyresolution
I but high-WMC readers showed the strongest slow-down
I and low-WMC readers showed a speed-up
18 / 24
Increased processing difficulty does not necessarily lead to longerRTs
I low-WMC subjects may take less time when ambiguities arepresent (but they had worst accuracy) than high-WMCs(MacDonald, Just, & Carpenter, 1992; Pearlmutter & MacDonald, 1995;
Malsburg & Vasishth, 2012)
I low-WMC subjects can read superficially enough to drawcontradicting conclusions from a text (Oberauer, Weidenfeld, &
Hornig, 2006)
I similar results in previous study (only for SPR) (Nicenboim,
Vasishth, Gattei, Sigman, & Kliegl, 2014)
19 / 24
Increased processing difficulty does not necessarily lead to longerRTs
I low-WMC subjects may take less time when ambiguities arepresent (but they had worst accuracy) than high-WMCs(MacDonald et al., 1992; Pearlmutter & MacDonald, 1995; Malsburg &
Vasishth, 2012)
I low-WMC subjects can read superficially enough to drawcontradicting conclusions from a text (Oberauer et al., 2006)
I similar results in previous study (only for SPR) (Nicenboim
et al., 2014)
19 / 24
Increased processing difficulty does not necessarily lead to longerRTs
I low-WMC subjects may take less time when ambiguities arepresent (but they had worst accuracy) than high-WMCs(MacDonald et al., 1992; Pearlmutter & MacDonald, 1995; Malsburg &
Vasishth, 2012)
I low-WMC subjects can read superficially enough to drawcontradicting conclusions from a text (Oberauer et al., 2006)
I similar results in previous study (only for SPR) (Nicenboim
et al., 2014)
19 / 24
Increased processing difficulty does not necessarily lead to longerRTs
I low-WMC subjects may take less time when ambiguities arepresent (but they had worst accuracy) than high-WMCs(MacDonald et al., 1992; Pearlmutter & MacDonald, 1995; Malsburg &
Vasishth, 2012)
I low-WMC subjects can read superficially enough to drawcontradicting conclusions from a text (Oberauer et al., 2006)
I similar results in previous study (only for SPR) (Nicenboim
et al., 2014)
19 / 24
Explanation
1. longer RTs of high-WMC readers may be due tomemory-driven locality effects
2. shorter RTs of low-WMC readers may be due to failure atretrieval and incomplete parsing
3. Can (1) and (2) explain the data?
20 / 24
Explanation
1. longer RTs of high-WMC readers may be due tomemory-driven locality effects
2. shorter RTs of low-WMC readers may be due to failure atretrieval and incomplete parsing
3. Can (1) and (2) explain the data?
20 / 24
Explanation
1. longer RTs of high-WMC readers may be due tomemory-driven locality effects
2. shorter RTs of low-WMC readers may be due to failure atretrieval and incomplete parsing
3. Can (1) and (2) explain the data?
20 / 24
Model
Average RT at the verb assuming only one dependent:av RT = Baseline+ pr (dep) (Tr (dep) + Tintegration) + (1-pr (dep)) Tfailure
Probability of successfull retrieval of a dependent:pr (dep) = f(distance, wmc, encoding)
Time required for a successfull retrieval of a dependent:Tr (dep) = g(distance, encoding)
Other assumptions:
I Tfailure < Tr (dep)
I Tintegration > 0
Average RT at the verb:
av RT = Baseline+∏
pr (dep) (∑
Tr (dep) + Tintegration) + ...
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Model
Average RT at the verb assuming only one dependent:av RT = Baseline+ pr (dep) (Tr (dep) + Tintegration) + (1-pr (dep)) Tfailure
Probability of successfull retrieval of a dependent:pr (dep) = f(distance, wmc, encoding)
Time required for a successfull retrieval of a dependent:Tr (dep) = g(distance, encoding)
Other assumptions:
I Tfailure < Tr (dep)
I Tintegration > 0
Average RT at the verb:
av RT = Baseline+∏
pr (dep) (∑
Tr (dep) + Tintegration) + ...
21 / 24
Model
Average RT at the verb assuming only one dependent:av RT = Baseline+ pr (dep) (Tr (dep) + Tintegration) + (1-pr (dep)) Tfailure
Probability of successfull retrieval of a dependent:pr (dep) = f(distance, wmc, encoding)
Time required for a successfull retrieval of a dependent:Tr (dep) = g(distance, encoding)
Other assumptions:
I Tfailure < Tr (dep)
I Tintegration > 0
Average RT at the verb:
av RT = Baseline+∏
pr (dep) (∑
Tr (dep) + Tintegration) + ...
21 / 24
Model
Average RT at the verb assuming only one dependent:av RT = Baseline+ pr (dep) (Tr (dep) + Tintegration) + (1-pr (dep)) Tfailure
Probability of successfull retrieval of a dependent:pr (dep) = f(distance, wmc, encoding)
Time required for a successfull retrieval of a dependent:Tr (dep) = g(distance, encoding)
Other assumptions:
I Tfailure < Tr (dep)
I Tintegration > 0
Average RT at the verb:
av RT = Baseline+∏
pr (dep) (∑
Tr (dep) + Tintegration) + ...
21 / 24
Model
Average RT at the verb assuming only one dependent:av RT = Baseline+ pr (dep) (Tr (dep) + Tintegration) + (1-pr (dep)) Tfailure
Probability of successfull retrieval of a dependent:pr (dep) = f(distance, wmc, encoding)
Time required for a successfull retrieval of a dependent:Tr (dep) = g(distance, encoding)
Other assumptions:
I Tfailure < Tr (dep)
I Tintegration > 0
Average RT at the verb:
av RT = Baseline+∏
pr (dep) (∑
Tr (dep) + Tintegration) + ...
21 / 24
Average RT at the verb assuming only one dependent:av RT = Baseline+ pr (dep) (Tr (dep) + Tintegration) + (1-pr (dep)) Tfailure
22 / 24
Average RT at the verb assuming only one dependent:av RT = Baseline+ pr (dep) (Tr (dep) + Tintegration) + (1-pr (dep)) Tfailure
22 / 24
Summary
I Increased dependency length leads to more processingdifficulty
I But we see locality effects (slow downs) only when thedependency can be resolved
I And speed-ups associated with failed retrieval if thedependency can not resolved
I A computational model can capture the pattern found inthe data (under very specific assumptions)
23 / 24
Summary
I Increased dependency length leads to more processingdifficulty
I But we see locality effects (slow downs) only when thedependency can be resolved
I And speed-ups associated with failed retrieval if thedependency can not resolved
I A computational model can capture the pattern found inthe data (under very specific assumptions)
23 / 24
Summary
I Increased dependency length leads to more processingdifficulty
I But we see locality effects (slow downs) only when thedependency can be resolved
I And speed-ups associated with failed retrieval if thedependency can not resolved
I A computational model can capture the pattern found inthe data (under very specific assumptions)
23 / 24
Summary
I Increased dependency length leads to more processingdifficulty
I But we see locality effects (slow downs) only when thedependency can be resolved
I And speed-ups associated with failed retrieval if thedependency can not resolved
I A computational model can capture the pattern found inthe data (under very specific assumptions)
23 / 24
24 / 24