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!

3. 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

IQ/ reasoning

Memory Language

√ √ √

(Cipolotti , Butterworth and Denes, 1991)

Numeracy Tasks

0

20

40

60

80

100

120

Reading aloud

Reciting numbers

What comes next

Calculation

Pe

rce

nt

corr

ect

Number facts

LEFT FRONTO PARIETAL DAMAGE

>4<4

Size Judgements (e.g. which object is biggest in real life?)

Measure Terms(e.g. which denotes a bigger quantity:

metre/km)

Judgements of more(e.g. can you fit more coffee beans or

grains of salt in a cup)

√ √ √

Transitivity

(e.g. John is taller than Fred. Fred is taller than Peter. Who is

Tallest?)

Classification Class inclusion (e.g. if you have 16 roses and 6 tulips, do you have

more roses or more flowers?)

One-to-one correspondence (e.g. give these sticks to 2

or 4 or 6 people)

√ √ √ √

A deficit in the reasoning abilities thought to underlie the concept of numbers

An impairment in dealing with quantities

CG- loss of numbers >4

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 Picturenaming pointing

Animals 80 100

Fruits & Vegetables 100 100

Body Parts 100 100

Musical Instruments 90 100

Vehicle 80 100

Household Objects 100 100

3 SD pts IQ/ reasonin

g

STM Calculation

HAB (Rossor et al. 1995)

IH (Cappelletti et al, 2001)

AM (Cappelletti et al. 2006)

√√√

√√√

√√√

Parietal lobes preserved: Number knowledge intact but impaired Semantic knowledge

IH

e.g. HAB’s spontaneous speech reduced to stereotype phrases ‘I don’t know’ and jargon utterances “millionaire bub”

Spontaneous Speech

Compreh. Naming

XXX

XXX

XXX

Semantic knowledge X

Visual tasks

Naming task

?Matching task

Average of <20% correct

Average of <2SD above chance

Numerical knowledge √

• Non-verbal number tasks (minimal linguistic skills)

0 10037 ?

How many?

23 x 35 = ?

Average of 90% correct

Average of 95% correct

Average of 85% correct

• Verbal number tasks (requiring linguistic skills)

• Calculation tasks (knowledge of number facts, arithmetical procedures)

Butterworth et al., 2001; Cappelletti et al., 2002

Reading, writing and semanticsEightYouSixteenCashSixtyFlashHundredCanyonNinetyBasicSeventyGaveNineEventSeventeen

0

20

40

60

80

100

120

Numbers Words

% C

orre

ct

Reading Writing Semantics

writing to dictation

Reading aloud

Reading and writing number names √

Numerical knowledge √

Semantic knowledge X

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 ALOUD (Pt R1)

StimulusResponse

80 X “eight”

406 X “forty six”

Eighty √

Four hundred and six √

Moustache √

Column √

WRITING TO DICTATION (Pt W)

“Three thousand two hundred” X 3000.200

“One thousand” X 1000,000

Moustache √ Column √

Reading Writing

3. 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 impairmentsArithmetical fact impairments

+

-

x

/

Patient A 56 92 92 - Patient S1 92 48 88 - Patient S2 88 74 100 - Patient M1 88 96 68 - Patient D 96 92 88 0

Percentage correct

Patient S2:

MRI showing lesion in supramarginal gyrus abutting the left intraparietal sulcus. The right hemisphere is normal.

Patient M1:

MRI approximately five centimeters from midline showing complete sparing of the left supramarginal gyrus and left angular gyrus.