Evidence of the impact of visuo-spatial processing on magnitude representation in 22q11.2 microdeletion syndrome.
The influence of visuo-spatial skills on numerical magnitude processing is the subject of a long-standing debate. As most of the numerical and non-numerical magnitude abilities underpinning mathematical development are visual by nature, they are often assessed in the visual modality, thereby confusing visuo-spatial and numerical processing. In order to assess the influence of visuo-spatial processing on numerical magnitude representation, we examined magnitude processing in patients with 22q11.2 deletion syndrome (22q11DS), a genetic condition characterized by a cognitive profile with a relative weakness in visuo-spatial abilities but with preserved verbal abilities. Twenty-seven participants with 22q11DS were compared to two control groups (one matched on verbal intelligence and the other on visuo-spatial abilities) on several magnitude comparison tasks each with different visuo-spatial processing requirements. Our results showed that participants with 22q11DS present a consistent pattern of impairment in magnitude comparison tasks requiring the processing of visuo-spatial dimensions: comparison of lengths and collections. In contrast, their performance did not differ from the control groups in a visual task with no spatial processing requirement (i.e. numerical comparison of flashed dot sequences) or in auditory tasks (i.e., duration comparison and numerical comparison of sound sequences). Finally, a specific deficit of enumeration processes was observed in the subitizing range. Taken together, these results show that deficits in magnitude can occur as a consequence of a visuo-spatial deficit. This highlights the influence of the nature of the tasks selected to assess magnitude representation.
Research Unit "Enfances", University of Liège, Belgium; Psychological Sciences Research Institute, Catholic University of Louvain, Louvain-la-Neuve, Belgium. Electronic address: lucie.attout@ulg.ac.be.
Lucie
L
Attout
Psychological Sciences Research Institute, Catholic University of Louvain, Louvain-la-Neuve, Belgium.
Marie-Pascale
MP
Noël
Research Unit "Enfances", University of Liège, Belgium.
Line
L
Vossius
Research Unit "Enfances", University of Liège, Belgium.
Laurence
L
Rousselle
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D004062:DiGeorge Syndrome / Q000523:psychology*; D005260:Female; D006801:Humans; D007600:Judgment; D008297:Male; D055641:Mathematical Concepts; D008570:Memory, Short-Term; D009483:Neuropsychological Tests; D013028:Space Perception; D065855:Spatial Processing; D014796:Visual Perception; D055815:Young Adult
22q11 microdeletion syndrome; Magnitude representation; Numerical processing; Velo-cardio-facial syndrome; Visuospatial abilities