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Cognitive and educational neuroscience of
math learning: implications for
interventions in learning disabilities
Vinod Menon
Department of Psychiatry & Behavioral Sciences
Department of Neurology & Neurological Sciences
Symbolic Systems Program
Program in Neuroscience
Stanford University
http://braindevelopment.stanford.edu
Acknowledgements
Miriam Rosenberg-Lee
Teresa Iuculano
Soohyun Cho
Sarit Ashkenazi
Shaozheng Qin
Kaustubh Supekar
Dietsje Jolles
Other lab members
Dave Geary
Lynn Fuchs
Stanford Brain Development Project
Research Questions
in Educational Neuroscience
How does brain development influence learning?
What brain systems and circuits support academic skill acquisition?
How does learning go awry in some children?
What can be done to successfully remediate poor skills in struggling students?
Math Ability and Life Success
• Children’s math ability is highly predictive of future academic and
professional success, more than reading
• Math Disability (MD): 20% of children (3-6% dyscalculia)
• MD affects education, employment, everyday life situations
Current Research Topics in
Mathematical Cognition & Dyscalculia
Cognitive
• Differentiating between various components of mathematical information processing (e.g. calculation and retrieval)
• Contributions of working memory, attention, visuospatial abilities, abstract reasoning
• Performance under pressure , Math anxiety, Stereotype threat
• Mindset, Motivation
Developmental
• Development of number sense and problem solving abilities in children
Educational
• Development of remediation programs for individuals with poor math performance
Neurobiological
• Relative contribution of specific brain regions vs. distributed system function
• Neural basis of performance differences across individuals
• Neural basis of development and dysfunction in mathematical reasoning
Outline
• Brain organization for mathematical cognition– Multiple cognitive processes
– Multiple brain circuits
– Multiple sources of deficits in learning disabilities
• Developmental changes underlying mathematical skill development– Protracted developmental trajectory
– Fine-grain developmental differences during critical stages of skill acquisition
• Development of memory-based knowledge – Learning to use efficient strategies
– Crucial role of associative memory system
– Core memory systems play an important role in knowledge acquisition
• Training and brain plasticity – Normalization of brain response with training in children with learning disabilities
– Changes in functional and structural circuits
– Brain-based predictors of learning
• Implications for educational neuroscience and interventions in learning disabilities
Levels of Mathematical Information Processing
• Basic Number Processing– Symbol mapping
– Magnitude Judgment
• Fact Retrieval – Calculation vs. Automatic Retrieval
• Complex Mathematical Computation– Involves many other cognitive functions
• Working Memory
• Attention
• Visuospatial Processing
Which is bigger?
3 5
6 x 6 = 36
17 - 8 = ?
Basic number processing and fluent fact retrieval are key bottlenecks in dyscalculia.
3
Canonical brain areas involved in numerical
problem solving
Results of meta-analysis - 44
studies of arithmetic in adults
(Neurosynth, Yarkoni et al.
2011)
Ashkenazi et al., 2012 JLD.
Neurobiological basis of math and
reading disabilities
Distributed systems involved in math cognition and
learning
Menon (2013) Handbook Math Cogn.
Fias et al. (2013) Trends in Neursci Ed.
Cannot assume that same brain systems are
similarly involved in different stages of learning
Mathematical Skill Development
Developmental of Arithmetic skills
8 10 12 14 16 18 20
0
1
2
3
4
Nu
mb
er
of su
bje
cts
AgeRivera (2005) Cerebral Cortex
• Aim: Examine neurodevelopmental changes in mental arithmetic (ages 8-19)
• Task: Single-digit addition and subtractiona + b = ca – b = c
• Analysis: Age-related increases and decreases in
brain activation
Developmental changes: Behavior
• Accuracy: asymptotes by age 9
• RT: changes continue through adolescence
8 10 12 14 16 18 20
0.86
0.88
0.90
0.92
0.94
0.96
0.98
1.00
1.02
Accura
cy
Age
8 10 12 14 16 18 20
0.86
0.88
0.90
0.92
0.94
0.96
0.98
1.00
1.02
Accura
cy
Age
8 10 12 14 16 18 20
600
800
1000
1200
1400
1600
1800
2000
2200
2400
Reaction t
ime (
msec)
Age
8 10 12 14 16 18 20
600
800
1000
1200
1400
1600
1800
2000
2200
2400
Reaction t
ime (
msec)
Age
Experimental trials Control trials
Anterior to Posterior Shift in Arithmetic
Processing with Age
Rivera et al., 2005
Increases with age
Decreases with age
Addition & Subtraction
Combined
Age range: 8 – 19 years
Developmental changes: Children vs. Adults
PFC, MTL and basal ganglia are more
engaged in children
8 10 12 14 16 18 20
-3
-2
-1
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L S
FG
Age
8 10 12 14 16 18 20
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-1
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FG
Age
8 10 12 14 16 18 20
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-2
-1
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L I
FG
Age
8 10 12 14 16 18 20
-3
-2
-1
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L V
entr
al str
iatu
m
Age
8 10 12 14 16 18 20
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-1
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L P
uta
me
n
Age
8 10 12 14 16 18 20
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-2
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L F
G/P
HG
Age
8 10 12 14 16 18 20
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-2
-1
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L H
ipp
oca
mp
us
Age
But also - Basal ganglia,
hippocampus and
parahippocampal gyrus
Prefrontal cortex
Effortful processing Procedural and declarative memory systems
L Parietal and Lateral occipital cortex activation increases with age
8 10 12 14 16 18 20
-3
-2
-1
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L S
upra
ma
rgin
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yru
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Age
8 10 12 14 16 18 20
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nf.
Occip
ita
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yru
s
Age
Parietal and LOC are more engaged in adults
Summary: Neurodevelopmental changes in
mental arithmetic
• Older individuals showed greater activation in the left parietal cortex, along the supramarginal gyrus and adjoining anterior intra-parietal sulcus
• By contrast, younger subjects showed greater activation in the prefrontal cortex, including dorsolateral and ventrolateral prefrontal cortex and the anterior cingulate cortex – Reflects comparatively more working memory and attentional resources to
achieve similar levels of mental arithmetic performance
• Increased functional specialization of the left parietal cortex in mental arithmetic, a process that is accompanied by decreased dependence on memory and attentional resources with development
• Younger subjects also showed greater activation of the hippocampus and dorsal basal ganglia – Reflects greater demands placed on both declarative and procedural
memory systems
How does a child solve 7 + 8 ? Decoding
brain activity patterns associated with
counting and retrieval strategies
Counting Fingers
Sum
Max
Min
Verbal Counting
Sum
Max
Min
Counting-based
Memory-based
Decomposition
Retrieval
Increasing maturity
Dec
reas
ing
reac
tion t
imes
and c
ogn
itiv
e re
sourc
es
Geary (1994)
How does a child solve 7 + 8 ? Decoding brain activity
patterns associated with counting and retrieval strategies
Strategy session fMRI session
Cho (2011) Developmental Science
Performance Matched
How does a child solve 7 + 8 ?:
Decoding Children’s Brain Activity Patterns
during Counting versus Retrieval
• Participants
2-3 grade children (7-10 years)
• Behavioral task
1) strategy assessment session (e.g., 3 + 4 = ?)
- % of trials retrieved, % of trials counted, etc.
2) fMRI session
- standard addition (both addends greater than 1; e.g., 3 + 4 = 8 ?)
- plus 1 addition control (one of the addend is 1; e.g., 7 + 1 = 8 ?)
• Functional image analysis
- univariate approach based on GLM
- multivariate approach using searchlight classification
Distinct Neural RepresentationsRetrievers (n = 19) vs. Counters (n = 17) MVPA
Functional reorganization and
Enhanced Cognitive control Activation differences Retrievers vs. Counters
L VLPFC
overlaps with the
MVPA map
Summary
Retrieval and counting strategies during early learning are
characterized by distinct patterns of activity in a distributed
network of brain regions involved in arithmetic problem
solving and controlled retrieval of arithmetic facts.
Reorganization and refinement of neural activity patterns in
multiple brain regions, including the hippocampus, plays a
dominant role in the transition to memory-based arithmetic
problem solving.
Multivariate approaches can provide novel insights into fine-
scale developmental changes in the brain.
Cho (2011) Developmental Science
Hippocampal-prefrontal engagement and
dynamic causal interactions in the
maturation of children’s fact retrieval
Cho (2012) J Cogn Neurosci.
Retrieval Fluency
Increased PFC-PPC-MTL responses with
Retrieval Fluency
Increased MTL connectivity with
Retrieval Fluency
Dynamic Causal PFC-MTL Interactions
Cho (2012) J Cogn Neurosci.
Summary
Higher retrieval fluency associated with increased recruitment of hippocampus and
prefrontal cortex.
Significant effective connectivity of the right hippocampus with bilateral PFC.
Dynamic causal modeling analysis revealed strong bidirectional interactions
between the hippocampus and the PFC.
Causal influences from the left VLPFC to the hippocampus served as the main
“top–down” component, whereas causal influences from the hippocampus to the
left DLPFC served as the main “bottom–up” component of this retrieval network.
Hippocampal–prefrontal circuits are important in the early development of
arithmetic retrieval fluency.
Cho (2012) J Cogn Neurosci.
Hippocampus critical for learning
Hippocampal-neocortical functional
reorganization underlying children’s
cognitive development
• The ability to efficiently retrieve basic facts
from memory and bring them to bear in ever-
changing situations is a cardinal feature of
memory-based problem solving. (Siegler, 1996;
Geary, 2006)
• Little is known about how this ability
develops as the brain matures from childhood
through adolescence into adulthood?
Qin et al., Nature Neurosci. 2014
Overlapping waves theory
• Maturation of mathematical problem solving skills in children
Perc
enta
ge u
se
(Adapted from Chen & Siegler, 2000)Age & Experience
counting
Strategy 2 Strategy 3
Fact retrieval
• Over development, problem solving skills become less dependent on effortful
procedures i.e counting, and more gradually dependent on memory-based
strategies
Experimental designPerc
enta
ge u
se
Age & Experience
Strategy 1
Strategy 2 Strategy 3Fact retrieval
Exp-1: longitudinal fMRI study in children
Exp-2: cross-sectional in adolescents and adults
Experimental Design
Demographics
Experimental design and behavioral results
Developmental changes in accuracy and
reaction time during solving addition problems
Block design Event-related
Brain areas activated involved in solving
arithmetic problems in children
Longitudinal changes in hippocampal
engagement in children
Longitudinal decrease in prefrontal-parietal
engagement
Longitudinal changes in hippocampal-neocortical
functional coupling in relation to individual
improvements in children’s retrieval fluency
Developmental changes in medial temporal lobe
engagement from childhood through adolescence
into adulthood
Time-1 (a) Time-2 (b) Adolescents (c) Adults (d)
Longitudinal changes in hippocampal
engagement during childhood, and further
development through adolescence into adulthood
Trial-by-trial stability of representations in children at
Time-1 and Time-2 children, adolescents, and adults
Learning mechanisms in hippocampus
Summary
• Hippocampal system is pivotal to strategic transition from procedure-based to
memory-based problem-solving strategies.
• Transition to memory-based retrieval parallels increased hippocampal and
decreased prefrontal-parietal engagement during arithmetic problem solving.
• Longitudinal improvements in retrieval-strategy use are predicted by increased
hippocampal-neocortical functional connectivity.
• Beyond childhood, retrieval-strategy use continues to improve through
adolescence into adulthood and is associated with decreased activation but more
stable inter-problem representations in the hippocampus.
• Dynamic role of the hippocampus in the maturation of memory-based problem
solving and establish a critical link between hippocampal-neocortical
reorganization and children's cognitive development.
2. What are the neural mechanisms that drive
some children to acquire math skills faster than
others?
1. How do brain circuits change in
response to math learning in childhood?
Training and Neuroplasticity
• Growing interest in training-related changes of brain
structure and function associated with math and
dyscalculia
• Little is known about changes in brain circuits in
academic domains: especially math
Training and Neuroplasticity
Untrained vs. Trained Problems
Ischebek (2007, 2009).
Mathematical Disabilities
• Developmental math disability (dyscalculia) affects 5-6%
of school-age children (stable and persistent)
• The ability to quickly and accurately retrieve basic
arithmetic facts is one of the most consistent deficits in
children with mathematical disabilities
• Mathematical difficulties are common in school-age
children
• Much less studied than dyslexia
• Major consequences for academic success
Cognitive Learning: Study design
Training and Neuroplasticity
Normalization of aberrant functional brain responses in
dyscalculic children after 8 weeks of math tutoring
Normalization of aberrant functional brain
responses in dyscalculic children after 8 weeks of
math tutoring
Changes in MLD vs. TD groups
Brain plasticity and normalization
• 8 weeks of 1:1 cognitive tutoring not only remediates poor performance in
children with MLD, but also induces widespread changes in brain activity
• Neuroplasticity manifests as normalization of aberrant functional responses in a
distributed network of parietal, prefrontal and ventral temporal-occipital areas
that support successful numerical problem-solving
• Remarkably, machine learning algorithms show that brain activity patterns in
children with MLD are significantly discriminable from neurotypical peers
before, but not after, tutoring
• Multivariate measures reveal that children with MLD with greater
neuroplasticity also exhibit larger performance gains with tutoring
• Identifies functional brain mechanisms underlying effective intervention in
children with MLD and provides novel metrics to track remediation
Summary
2. How do intrinsic brain circuits
change in response to math learning in
childhood?
Network View of Math Cognition
• Math cognition is accomplished via the dynamic assembly of brain regions.
• Connectivity between brain regions changes with development.
• Learning and remediation involve strengthening connections between key brain regions.
1. Select a seed: e.g. Left IPS
4. Functional connectivity of Left IPS
y= -48 z = 44 x = -46
2. Extract time course from seed
3. Correlated with time courses from other areas
Functional Connectivity Analyses
Math tutoring strengthens functional
connectivity between parietal cortex and
hippocampus
p < .01 height, 128 voxels
5
0t-sc
ore
0
0.02
0.04
0.06
beta
x = -22
Jolles et al, under review
Left Intra-Parietal
Sulcus (IPS)
Hippocampus
Hippocampus
z = 6
p < .01 height, 128 voxels
5
0t-sc
ore
Pre Post
0
0.05
0.1
0.15
Beta
L IFG R IFG
0
0.02
0.04
0.06
beta
x = -22
Jolles et al, under review
Left Intra Parietal
Sulcus (IPS)
Hippocampus
Bilateral IFG
Hippocampus
Math tutoring strengthens functional
connectivity
Performance gains are associated with
increased connectivity
Parietal-Hippocampal connectivity changes
Per
form
ance
chan
ges
• No changes in control group
0
0.5
1
1.5
2
-0.05 0 0.05 0.1 0.15
Brain-behavior correlations:
Jolles et al, under review
Cognitive Training Reduces Math Anxiety
Cognitive Training Reduces Amygdala
Reactivity
Supekar et al, under review
Cognitive Training Reduces Amygdala
Connectivity
Changes in Amygdala Reactivity Predicts
Reduction in a Child’s Math Anxiety
Remediation of aberrant amygdala reactivity
predicts tutoring-induced reductions in math anxiety
Neural predictors of individual differences in response to
math tutoring in primary-grade school children
Quantitative measures of brain structure and intrinsic
brain organization can provide a more sensitive marker of
skill acquisition than behavioral measures.
Supekar et al. PNAS 2013
Anatomical and functional predictors of
learning in children
Supekar et al. PNAS 2013
8-week Math Training
Neuropsychological assessments
(fMRI scan and math tasks)
fMRI scan and math tasks
Participants:
3rd grade children (N = 22)
Wide range of math abilities: 5th– 96th percentile
One-on-One Math tutoring
Math tutoring improves arithmetic performance
©2013 by National Academy of Sciences
Strategy shift
p = .067
Gray matter volume in hippocampus correlates with
improvement in arithmetic performance in response to
8 wk of one-to-one math tutoring
Functional connectivity of the hippocampus predicts
arithmetic performance improvements in response to
tutoring
©2013 by National Academy of Sciences
Functional connectivity of the hippocampus shows
highest correlation with arithmetic performance
improvement
©2013 by National Academy of Sciences
Summary – Training & Plasticity
• Tutoring normalizes widespread hyper-activation in children
with learning disabilities
• Multivariate measures reveal that children with MLD who
demonstrate greater neuroplasticity also exhibit larger
performance gains with tutoring
• Quantitative measures of brain structure and intrinsic brain
organization can provide a more sensitive marker of skill
acquisition than behavioral measures
• In typically developing children, training strengthens intrinsic
functional circuits linking numerical and mnemonic processes,
resulting in more efficient performance
• Cognitive tutoring can reduce anxiety
Conclusions
• Brain organization for mathematical cognition– Multiple cognitive processes
– Multiple brain circuits
– Multiple sources of deficits in learning disabilities
• Developmental changes underlying mathematical skill development– Protracted developmental trajectory
– Fine-grain developmental differences during critical stages of skill acquisition
• Development of memory-based knowledge – Learning to use efficient strategies
– Crucial role of associative memory system
– Core memory systems play an important role in knowledge acquisition
• Training and brain plasticity – Normalization of brain response with training in children with learning disabilities
– Changes in functional and structural circuits
– Brain-based predictors of learning
• Implications for educational neuroscience and interventions in learning disabilities
Brain systems involved in math learning change
dynamically with age and skill
Menon (2013) Handbook Math Cogn.