Testing the Mathematics Advantage Hypothesis in Students with ASD

Background: Students with ASD may display an advantage with spatial ability and mathematics (Baron Cohen, 2002). Consequently promoting ASD student involvement in STEM curriculums may be useful in schools (Wei et al. 2013, 2014). However, research is inconsistent with significant heterogeneity in mathematics development observed across students with ASD (Chiang & Lin, 2007) and a pattern of strength in calculation, but significant difficulty with verbal problem solving has been observed for affected students (Wei et al. 2015).

Objectives: To examine the mathematics advantage hypothesis of ASD this study compare students with ASD, typical development and ADHD on math achievement. The study also examined the relations between math development and spatial ability, reading, social-cognition and working memory.

Methods: 159 children participated including 77 with ASD (M = 8.51 years, SD = .21), 39 with ADHD symptoms (M = 8.46 years, SD = .19), and 43 with typical development (M = 8.47 years, SD = .19). The groups were divided and matched in Lower and Higher VIQ subgroups, ASD 90.4 (8.7), 113.4 (7.8), ADHD 92.2 (8.1), 117.5 (9.4), and TD Group 95.5 (7.1), 119.5 (9.3), respectively. ASD diagnosis was confirmed with the ADOS-2, and ADHD symptoms were confirmed with the Conner’s Parent Rating Scale-3. The students were assessed three times over 30 months with the Numerical Operations and Problem Solving Scales of Wechsler Individualized Achievement Tests-V, as well as the Wide Range Assessment of Memory and Learning, and the Gray Oral Reading Tests-5, and a silent movies Theory of Mind (ToM) task. The WASI was used for IQ and the Block Design Scale provided the spatial processing index.

Results: The TD group exhibited better performance on both math measures than the clinical groups, which did not differ, F (2, 106) = 11.20, p < .001, partial eta² = .18. The ASD group performed better on Numerical Operations than Problem Solving, F (1, 49) = 12.8, p < .001, partial eta² = .21, but this effect was not observed for the other groups. Greater difficulty in Problem Solving in the ASD versus TD comparison was evident in the lower VIQ subgroups than higher subgroup, F (1, 87) = 4.42, p < .04, partial eta² = .04. ToM was only associated with math performance in the ASD group. However, regressions indicated that only Time-1 VIQ, Block Design and Symbolic Working memory predicted Time- 3 Problem solving in the ASD sample, adj R ² = .58, p < .001. Different patterns of predictors were observed in the other groups.

Conclusions: Difficulty with math learning may be a characteristic of many students with ASD, especially those with VIQs below 105. Thus, learning differences associated with IQ may be important to examine among ASD students without intellectual disabilities. The math learning of lower average IQ students with ASD may require greater classroom support than is currently recognized and perhaps specific assistance with spatial and working memory development. These data are not consistent with the hypothesis of a general mathematics advantage for ASD students.