In Honour of Brian
Butterworth
Numeracy skills and Parietal lobes
Lisa Cipolotti &
Marinella Cappelletti
REVIEW OF PTS WITH UNILATERAL LESIONS
Primary dyscalculia does not exist.
Only secondary to impairments of: language; memory;
visuo-perception; intelligence (as measured by IQ)
(Collignon, Leclercq & Mahy’s review, 1977)
HISTORICAL REVIEW OF PUBLISHED CASES
‘… a summary of the cases of acalculia since Henschen
leads to the conclusion that…..
……there is neither a localised region nor a specific
hemisphere underlying the disorder …’
(Kahn & Whitaker, 1991)
Neurocognitive architecture of numeracy
skills
Work directly conducted or inspired by Brian
No of papers 1991- to date= at
least 60!
1. Numeracy independent of other cognitive skills ?
2. Relationship between cultural domains such as
number / general semantic knowledge?
3. Specialization for different types of symbols- Arabic
numeral (9) Words (nine)- within the cultural domains
of reading and writing ?
4. Organization of calculation system? arithmetical facts
1. Independence- Patient CG-LOSS OF NUMBERS >4
LEFT
FRONTO
PARIETAL
DAMAGE
IQ/
reasoning
Memory
Language
√
√
√
Numeracy Tasks
120
Percent correct
100
>4
<4
80
60
40
20
0
Reading
aloud
Reciting
numbers
What comes
next
Calculation
Number
facts
(Cipolotti , Butterworth and Denes, 1991)
CG- loss of numbers >4
An impairment in dealing with quantities
Size Judgements
Measure Terms
Judgements of more
(e.g. which object is biggest in real life?)
(e.g. which denotes a bigger quantity:
metre/km)
(e.g. can you fit more coffee beans or
grains of salt in a cup)
√
√
√
A deficit in the reasoning abilities thought to underlie the
concept of numbers
Transitivity
Classification
(e.g. if you have 16 roses
and 6 tulips, do you have
more roses or more
flowers?)
(e.g. John is taller than Fred.
Fred is taller than Peter. Who is
Tallest?)
√
Class inclusion
√
√
One-to-one
correspondence
(e.g. give these sticks to 2
or 4 or 6 people)
√
2. Relationship between cultural domains such as number/general semantic
Knowldge?
CG: Parietal impairment- loss of numbers >4 BUT preserved semantic
memory
% correct answers
Picture
naming
Picture
pointing
Animals
80
100
Fruits & Vegetables
100
100
Body Parts
100
100
Musical Instruments
90
100
Vehicle
80
100
Household Objects
100
100
Parietal lobes preserved: Number knowledge intact but
impaired Semantic knowledge
3 SD pts
HAB (Rossor et al. 1995)
IH (Cappelletti et al, 2001)
AM (Cappelletti et al. 2006)
IQ/
reasonin
g
STM
√
√
√
√
√
√
Calculation
√
√
√
Spontaneous
Speech
Compreh.
Naming
X
X
X
X
X
X
X
X
X
IH
e.g. HAB’s spontaneous speech reduced to stereotype phrases ‘I don’t
know’ and jargon utterances “millionaire bub”
Semantic knowledge X
Visual tasks
Matching task
?
Average of <2SD above chance
Naming task
Average of <20% correct
Numerical knowledge √
• Non-verbal number tasks (minimal linguistic skills)
0
100
37 ?
Average of 90% correct
• Verbal number tasks (requiring linguistic skills)


How many?

•

Average of 95% correct
Calculation tasks (knowledge of number facts, arithmetical
procedures) 23 x
35 =
?
Average of 85% correct
Reading
aloud
Eight
 You
Sixteen
 Cash
Sixty
 Flash
Hundred
 Canyon
Ninety
 Basic
Seventy
 Gave
Nine
 Event
Seventeen
Reading, writing and semantics
120
100
% Correct
writing to dictation
Reading and writing number names √
Numerical knowledge √
Semantic knowledge X
80
60
40
Reading
Writing
Semantic
20
0
Numbers
Words
Butterworth et al., 2001; Cappelletti et al., 2002
3. Specialization for different symbols- 9 vs nine- within the
cultural domains of reading and writing
3 patients (Pt R1, Pt R2, Pt W) with left
parietal lobe lesions (not exclusively)
Number comprehension
Reading
√
Writing
100
90
80
70
% correct
READING ALOUD (Pt R1)
60
Stimulus
Response
80
406
Eighty
Four hundred and six
Moustache
Column
X “eight”
X “forty six”
√
√
√
√
50
40
WRITING TO DICTATION (Pt W)
30
20
10
0
Pt R1
Arabic Numerals
Pt R2
Number Names
Pt W
Words
“Three thousand two hundred”
“One thousand”
X 3000.200
X 1000,000
Moustache
Column
√
√
1. Numeracy independent of other cognitive skills ?
2. Relationship between cultural domains such as
number / general semantic knowledge?
3. Specialization for different types of symbols- Arabic
numeral (9) Words (nine)- within the cultural domains
of reading and writing ?
4. Organization of calculation system? arithmetical facts
Arithmetical fact impairments
Percentage correct
Patient A
Patient S1
Patient S2
Patient M1
Patient D
+
-
x
/
56
92
88
88
96
92
48
74
96
92
92
88
100
68
88
0
Patient M1:
MRI
approximately
five
centimeters from midline
showing complete sparing of
the left supramarginal gyrus
and left angular gyrus.
Patient S2:
MRI showing lesion in supramarginal
gyrus abutting the left intraparietal
sulcus. The right hemisphere is
normal.