Number processing and arithmetic skills in children with cochlear implants

Listening comprehension in profoundly deaf children with cochlear implants: the role of auditory perception and foundational linguistic and cognitive skills

PURPOSE

The aim of the study was to investigate the listening comprehension (LC) skills in deaf and hard of hearing children (DHH) using cochlear implants (CI). Besides, personal and audiological variables that could influence the levels of competence reached were analyzed.

METHODS

Thirty-four children using CI were enrolled. LC skills were assessed through the standardized Italian test "Comprensione Orale-Test e Trattamento" (CO-TT). A univariate analysis was conducted to compare LC with gender, listening mode (unilateral or bilateral), maternal level of education and family income. A bivariate analysis was performed to search possible connections between children's performances and their individual characteristics, audiological conditions, and language levels. Finally, a multivariate analysis was performed using a stepwise hierarchical linear regression model which included all variables whose p value resulted  ≤ 0.05.

RESULTS

Twenty-one children using CI (61.8%) showed adequate performances in terms of chronological age, while 13 (38.2%) showed difficulties in LC. Maternal level of education, age at diagnosis and non-verbal cognitive level accounted for 43% of the observed variance. Auditory attention skills explained an additional 15% of variance. Morphosyntactic comprehension added a further 12% of variance.

CONCLUSION

CI can really help many DHH children to reach adequate LC skills, but in some cases difficulties remain. Factors influencing LC need to be early investigated and considered when planning an appropriate rehabilitative intervention.

Approximate Number Sense in Students With Severe Hearing Loss: A Modality-Neutral Cognitive Ability

The Approximate Number System (ANS) allows humans and non-human animals to estimate large quantities without counting. It is most commonly studied in visual contexts (i.e., with displays containing different numbers of dots), although the ANS may operate on all approximate quantities regardless of modality (e.g., estimating the number of a series of auditory tones). Previous research has shown that there is a link between ANS and mathematics abilities, and that this link is resilient to differences in visual experience (Kanjlia et al., 2018). However, little is known about the function of the ANS and its relationship to mathematics abilities in the absence of other types of sensory input. Here, we investigated the acuity of the ANS and its relationship with mathematics abilities in a group of students from the Sichuan Province in China, half of whom were deaf. We found, consistent with previous research, that ANS acuity improves with age. We found that mathematics ability was predicted by Non-verbal IQ and Inhibitory Control, but not visual working memory capacity or Attention Network efficiencies. Even above and beyond these predictors, ANS ability still accounted for unique variance in mathematics ability. Notably, there was no interaction with hearing, which indicates that the role played by the ANS in explaining mathematics competence is not modulated by hearing capacity. Finally, we found that age, Non-verbal IQ and Visual Working Memory capacity were predictive of ANS performance when controlling for other factors. In fact, although students with hearing loss performed slightly worse than students with normal hearing on the ANS task, hearing was no longer significantly predictive of ANS performance once other factors were taken into account. These results indicate that the ANS is able to develop at a consistent pace with other cognitive abilities in the absence of auditory experience, and that its relationship with mathematics ability is not contingent on sensory input from hearing.

Longitudinal development of subtraction performance in elementary school

A major goal of education in elementary mathematics is the mastery of arithmetic operations. However, research on subtraction is rather scarce, probably because subtraction is often implicitly assumed to be cognitively similar to addition, its mathematical inverse. To evaluate this assumption, we examined the relation between the borrow effect in subtraction and the carry effect in addition, and the developmental trajectory of the borrow effect in children using a choice reaction paradigm in a longitudinal study. In contrast to the carry effect in adults, carry and borrow effects in children were found to be categorical rather than continuous. From grades 3 to 4, children became more proficient in two-digit subtraction in general, but not in performing the borrow operation in particular. Thus, we observed no specific developmental progress in place-value computation, but a general improvement in subtraction procedures. Statement of contribution What is already known on this subject? The borrow operation increases difficulty in two-digit subtraction in adults. The carry effect in addition, as the inverse operation of borrowing, comprises categorical and continuous processing characteristics. What does this study add? In contrast to the carry effect in adults, the borrow and carry effects are categorical in elementary school children. Children generally improve in subtraction performance from grades 3 to 4 but do not progress in place-value computation in particular.