TY - JOUR
T1 - Developmental trajectory of number acuity reveals a severe impairment in developmental dyscalculia
AU - Piazza, Manuela
AU - Facoetti, Andrea
AU - Trussardi, Anna Noemi
AU - Berteletti, Ilaria
AU - Conte, Stefano
AU - Lucangeli, Daniela
AU - Dehaene, Stanislas
AU - Zorzi, Marco
PY - 2010/7
Y1 - 2010/7
N2 - Developmental dyscalculia is a learning disability that affects the acquisition of knowledge about numbers and arithmetic. It is widely assumed that numeracy is rooted on the "number sense", a core ability to grasp numerical quantities that humans share with other animals and deploy spontaneously at birth. To probe the links between number sense and dyscalculia, we used a psychophysical test to measure the Weber fraction for the numerosity of sets of dots, hereafter called number acuity. We show that number acuity improves with age in typically developing children. In dyscalculics, numerical acuity is severely impaired, with 10-year-old dyscalculics scoring at the level of 5-year-old normally developing children. Moreover, the severity of the number acuity impairment predicts the defective performance on tasks involving the manipulation of symbolic numbers. These results establish for the first time a clear association between dyscalculia and impaired "number sense", and they may open up new horizons for the early diagnosis and rehabilitation of mathematical learning deficits.
AB - Developmental dyscalculia is a learning disability that affects the acquisition of knowledge about numbers and arithmetic. It is widely assumed that numeracy is rooted on the "number sense", a core ability to grasp numerical quantities that humans share with other animals and deploy spontaneously at birth. To probe the links between number sense and dyscalculia, we used a psychophysical test to measure the Weber fraction for the numerosity of sets of dots, hereafter called number acuity. We show that number acuity improves with age in typically developing children. In dyscalculics, numerical acuity is severely impaired, with 10-year-old dyscalculics scoring at the level of 5-year-old normally developing children. Moreover, the severity of the number acuity impairment predicts the defective performance on tasks involving the manipulation of symbolic numbers. These results establish for the first time a clear association between dyscalculia and impaired "number sense", and they may open up new horizons for the early diagnosis and rehabilitation of mathematical learning deficits.
KW - Developmental dyscalculia
KW - Non-symbolic number comparison
KW - Numerical cognition
KW - Numerical development
UR - http://www.scopus.com/inward/record.url?scp=77952888628&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=77952888628&partnerID=8YFLogxK
U2 - 10.1016/j.cognition.2010.03.012
DO - 10.1016/j.cognition.2010.03.012
M3 - Article
C2 - 20381023
AN - SCOPUS:77952888628
VL - 116
SP - 33
EP - 41
JO - Cognition
JF - Cognition
SN - 0010-0277
IS - 1
ER -