Dyscalculia – the neglected learning disorder

1. Dyscalculia – the neglected learning disorder Karin Landerl University of Graz

2. Dyscalculia – the neglected learning disorder (Pubmed Database)

3. Celebrities with dyslexia Hans Christian Andersen John Irving Agatha Christie Cher Winston Churchill Leonardo DaVinci Charles Darwin Walt Disney Whoopi Goldberg Tom Cruise Thomas Edison Swedish Royal Family  Greg Louganis Jackie Stewart Michelangelo Pablo Picasso August Rodin Nelson Rockefeller Franklin Roosevelt Vincent VanGogh Woodrow Wilson Celebrities with dyscalculia??

4. Prevalence rates: Studies in GB, Germany, Greece, India, Israel (Badian, 1983; Gross-Tsur, Manor, & Shalev, 1996; Hein, Bzufka & Neumärker, 2000; Klauer, 1992; Kosc, 1974; Koumoula, Tsironi, Starmouli, Bardani & Siapati, 2004; Lewis, Hitch & Walker, 1994; Ramaa & Gowaramma, 2002; von Aster, Schweiter & Weinhold Zulauf, 2007) Comparable prevalence rates ranging from 3 to 8.3 % No clear gender differences

5. Overview • Whatisdyscalculia? • Neuro-cognitivetheoriesoflearningdisorders • Core deficits in processingnumerosities • Implicationsfordiagnosisandintervention

6. DYSCALCULIA Definition: (ICD-10)"...a condition that affects the ability to acquire arithmetical skills. Dyscalculic learners may have difficulty understanding simple number concepts, lack an intuitive grasp of numbers, and have problems learning number facts and procedures. Even if they produce a correct answer or use a correct method, they may do so mechanically and without confidence" (UK Department for Education and Science, 2001).

7. Case description . in elementary school, I didn´t understand for a long time why 1 + 1 = 2 – I thought it should be 11 I always had problems when new concepts or procedures were introduced, I was insecure and didn´t get it. Only when we were almost through and everzbody else understood, I sometimes got a basic idea, understood maybe half of it. Still, I mostly learned procedures by heart, without really understanding. If there was only a small change in the problems given, I was again completely lost.

8. Case description . I never understood word problems– still don´t. I just don´t get what I´m supposed to do I cannot visualise amounts or magnitudes. How much are 100 g? I just don´t have it in my head. I cannot convert – for example grams in kilograms. So I have problems to bake a cake when the recipe has other measures than what I need

9. Case description . I am poor in mental calculations… most often I keep counting in my head. For example, when I´m asked to add up 16 + 18, I can do 10 + 10 alright – that´s 20. But the 6 and the 8 are difficult then, that takes longer. I need to add them to the 20 and at the same time remember… and when it gets more diffcult with divisions or so, I give up completely. I still count on my fingers – if anybody is watching me, I try to do it in my head.

10. Case description . I have problems with percentages – they just don´t mean anything to me. Decimals I find especially hard – adding or subtracting them – oh my god – there´s only chaos in my brain I don´t realise it when I come up with a completely incorrect result, because the numbers don´t mean anything to me, I cannot estimate if my result might be right or wrong

11. Case description . or to remember things like: "were there 600 or 6000 people at the festival?". I cannot estimate the number of inhabitants of some place, it just doen´t mean anything to me. Are there 10.000 people living in Germany or was it 100.000 or more or less? I don´t have a clue.

12. 10000 - 204 = • First, I needed to think how to calculate 10000 - 204. At some point I decided to do 10000 - 100 = 9000 and then again subtract 100 = 8000. and then there´s only 4 left of the 204, which I needed to subtract. It was easy to write down 79, same with the following 9 (799), though a bit slower, and then the 6. So the result is 7996. I have no idea if this could be correct as I don´t have my calculator with me.

13. Neurocognitive Theories of Inborn Core Mechanisms • Babies are born witha number of simple core mechanisms that are criticalforfurther development • These inborn core mechanisms enable fast-track learning (with normal environmental stimulation) • What happens if the core mechanism doesn´t function properly?  Developmental disorder

14. What is the critical core mechanism of dyslexia? Phonological processing Enables fast-track learning of language and literacy Phonological deficits – delay in language development and serious problems in reading acquisition Learning is slow and compensatory

15. Is there a core mechanism for arithmetic skills?

16. Same as for dyslexia?

17. Phonological awareness? „Say /ti:k/ without /k/“ Landerl, Fussenegger, Moll & Willburger (2009), Journal of Experimental Child Psychology

18. Naming Speed for Digits Landerl, Fussenegger, Moll & Willburger (2009), Journal of Experimental Child Psychology

19. Babies process numerosties Starr, Libertus, & Brannon (2013) PNAS

20. Babies process numerosities Xu, Spelke & Goddard (2006)

22. Babies can do simple arithmetic

23. Wynn (1992)

24. Babies are attentive towards numerosities = core system number sense – Dehaene (1997) number module – Butterworth (1999) Dysfunctional core system atypical development of the cognitive representation of numbers DYSCALCULIA

25. Deficits in numerical processing in dyscalculia:Magnitude comparison

26. Magnitude comparison Lese-Kontrast: Gruppe: F < 1, n.s.

27. Arabic numbers = symbols for numerosities • 8 • 32 58 Number comparison – Requires access to the magnitudes represented by the symbols

28. Number comparison Landerl, Fussenegger, Moll & Willburger (2009), Journal of Experimental Child Psychology

29. Basic numerical processing as a core deficit of dyscalculia N – Numerical comparison 5 7 P – Physical comparison (neutral condition): 5 5

30. Comparison of two-digit numbers Compatible: 52 76 incompatible: 47 62 Landerl (2013) Frontiers in Psychology

31. Dotcounting(Schleifer & Landerl, 2011, Developmental Science)

32. Butterworth (1999)

33. Everybody counts…

34. Biology Cognition Problem solving skills Visual-spatial skills Executive functions Working memory Verbal skills Long term memory basic numerical skills attention reading teaching intervention Arithmetic skills Behaviour

35. Basic numerical skills Biology IPS Analog magnitude representatio Cognition Visual-arabic representation Auditory-verbal representation   Mental number line Finger- representation stimulation teaching intervention Read/write/compare Arabic numbers Subitizing estimation Process number words  magnitude comparison  Finger- calculation counting Written calculations Number facts Behaviour

36. Schematische Darstellung der in der Literatur postulierten (und zum Teil noch kontrovers diskutierten) neuronalen Netzwerkkomponenten der Zahlenverarbeitung und des Rechnens PSPL (Posteriorer superiorer SMA (Supplementär-motorisches SMA (Supplementär-motorisches parietaler Lappen): räumliche Areal): antwortbezogene Konflikt- Areal): antwortbezogene Konflikt- Präfrontale Areale : Präfrontale Areale : Aufmerksamkeit auf der resolution, ev. Fingerrechnen resolution, ev. Fingerrechnen Monitoring, Monitoring, mentalen Zahlenlinie Arbeitsgedächtnis, Arbeitsgedächtnis, Strategien etc Strategien etc Posteriorer IPS und (H)IPS: R epräsentation des Basis-10- (Platz x Wert) Systems HIPS (horizontales Segment d. intraparietalen Sulcus): mentale Mengen-repräsentation per se Gyrus fusiformis: visuelle Perisylvische Verarbeitung von Wörtern / ev. Areale: Arabischen Zahlen Zählsequenzen, Gyrus angularis: Benennen von Faktenabruf (v.a. Zahlen, verbales Cerebellum: Aufgaben mit hoher Multiplikations- Rechnen Komplexität und/oder Neuheitswert fakten) (domänen-unspezifisch), eventuell auch Zählsequenzen Kaufmann & Nuerk (2007; Abb. 1) Brain areas that have been identified to be active during numerical processing /arithmetic

37. Dyslexia: under-activation in left temporo-parietal areas Paulesu et al. (2001) Dyscalculia: under-activation in intraparietal sulcus (bilaterally) Molko et al. (2003) Dyscalculia and Dyslexia : different neuro-functional abnormalities

38. Specialization of the neuro-cognitive network for numbers/arithmetic happens during development Areas whose activation increases with age Areas whose activation decreases with age Rivera et al. (2005)

39. Summary • Doing arithmetic requires a highly specified neuro-cognitive network • The starting point for the development of this network is an early core mechanism • The development and specification of the neuro-cognitve network for arithmetic takes many years and is strongly dependent on environmental factors (stimulation, teaching, intervention)

40. Dyscalculia • Inborn core mechanism is not functioning properly „Everybody counts, but not everybody understands numbers“ (Butterworth, 2005) • Development of the neuro-cognitive network underlying arithmetic is atypical, right from start. Learning is slow and compensatory • Early identification and intervention is important in order to support learning and avoid secondary symptoms (maths anxiety, behavioural problems)

41. Implications for diagnosis and intervention • Establish a profile of strengths and weaknesses in arithmetic and numerical processing as well as other ressources (and comorbidities) • Tailored intervention based on fine-grained diagnosis • Learning will often be compensatory and take more time Thank you for your attention!