Children with developmental dyscalculia often show impaired performance on number order processing tasks. Recent findings suggest these deficits are not general in nature but rather specific to certain kinds of sequences. One proposal by Slipenkyj and colleagues (2025) is that dyscalculic children struggle specifically to understand that “in order” can refer to sequences outside of the ascending-consecutive count-list. However, previous findings in support of this view were limited by (i) only considering ascending sequences and (ii) not accounting for other factors known to influence order processing performance such as sequence familiarity.
This presentation discusses a recent study in which CEN aimed to address these limitations. To do this, CEN compared a control (n = 28) and dyscalculic group (n = 12), aged 7-12 years, across ascending and descending sequences varying in familiarity. Consistent with the count-list perspective, dyscalculic children showed impaired performance on ascending non-consecutive sequences (e.g., 1-3-5) but not on ascending consecutive sequences (e.g., 1-2-3). Consistent with the familiarity perspective, accuracy was higher for familiar non-count-list sequences (e.g,. 2-4-6) than for unfamiliar non-count-list sequences (e.g., 2-5-8). Inconsistent with both perspectives, however, dyscalculic children displayed typical performance on descending sequences (e.g., 5-4-3, 5-3-1), which are both non-count-list and relatively unfamiliar. Accordingly, although order processing deficits in developmental dyscalculia do appear specific in nature, they are not necessarily specific to either non-count-list or unfamiliar sequences.
This is a CEN event.