In Honour of Brian Butterworth

1. In Honour of Brian Butterworth Numeracy skills and Parietal lobes Lisa Cipolotti & Marinella Cappelletti

2. 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)

3. 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)

4. Neurocognitive architecture of numeracy skills Work directly conducted or inspired by Brian No of papers 1991- to date= at least 60!

5. 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

6. 1.Independence- Patient CG-LOSS OF NUMBERS >4 120 100 80 Percent correct 60 40 20 0 Reading aloud Reciting numbers What comes next Calculation LEFT FRONTO PARIETAL DAMAGE Numeracy Tasks >4 <4 Number facts (Cipolotti , Butterworth and Denes, 1991)

7. CG- loss of numbers >4 An impairment in dealing with quantities A deficit in the reasoning abilities thought to underlie the concept of numbers

8. 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 Picture naming pointing Animals 80 100 Fruits & Vegetables 100 100 Body Parts 100 100 Musical Instruments 90 100 Vehicle 80 100 Household Objects 100 100

9. 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”

10. Semantic knowledge X Visual tasks ? Matching task Average of <2SD above chance Naming task Average of <20% correct

11. 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

12. Reading and writing number names √ Numerical knowledge √ Semantic knowledge X writing to dictation Reading aloud Reading, writing and semantics • Eight • You • Sixteen • Cash • Sixty • Flash • Hundred • Canyon • Ninety • Basic • Seventy • Gave • Nine • Event • Seventeen Butterworth et al., 2001; Cappelletti et al., 2002

13. 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) • Stimulus Response • 80 X “eight” • 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

14. 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

15. Arithmetical fact impairments 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.