Jodi Reich

Physical growth and nonverbal intelligence: associations in Zambia.

OBJECTIVE To investigate normative developmental body mass index (BMI) trajectories and associations of physical growth indicators--height, weight, head circumference (HC), and BMI--with nonverbal intelligence in an understudied population of children from sub-Saharan Africa. STUDY DESIGN A sample of 3981 students (50.8% male), grades 3-7, with a mean age of 12.75 years was recruited from 34 rural Zambian schools. Children with low scores on vision and hearing screenings were excluded. Height, weight, and HC were measured, and nonverbal intelligence was assessed using the Universal Nonverbal Intelligence Test, Symbolic Memory subtest and Kaufman Assessment Battery for Children, Second Edition, Triangles subtest. RESULTS Students in higher grades had a higher BMI over and above the effect of age. Girls had a marginally higher BMI, although that for both boys and girls was approximately 1 SD below the international Centers for Disease Control and Prevention and World Health Organization norms. When controlling for the effect of age, nonverbal intelligence showed small but significant positive relationships with HC (r = 0.17) and BMI (r = 0.11). HC and BMI accounted for 1.9% of the variance in nonverbal intelligence, over and above the contribution of grade and sex. CONCLUSION BMI-for-age growth curves of Zambian children follow observed worldwide developmental trajectories. The positive relationships between BMI and intelligence underscore the importance of providing adequate nutritional and physical growth opportunities for children worldwide and in sub-Saharan Africa in particular. Directions for future studies are discussed with regard to maximizing the cognitive potential of all rural African children.

Associations between household responsibilities and academic competencies in the context of education accessibility in Zambia.

The relationship between education and socioeconomic status has been demonstrated in studies of the developed and the developing world, yet there are communities in which schooling is either not available to all children or not a preferred activity for all children. In this study, we investigated the differences between children in-school and out-of-school in rural and peri-urban communities of Zambia. As expected, we found that the children in-school performed higher in domains of adaptive behavior and on assessments of academic achievement (i.e., mathematics, reading). Somewhat unexpectedly, however, when controlling for socioeconomic status, home responsibilities (i.e., chores, work) were a positive predictor for the performance of the children out-of-school, but a negative predictor for the children in-school. The relationship between home responsibilities and academic performance may be bidirectional and differential; for example, our findings allow for the hypothesis that for in-school children chores take time away from the studies, but for out-of-school children they provide some limited mathematics exposure.

Scalar Implicature in Chitonga-Speaking Children

Research on the acquisition of scalar implicature (SI) has provided evidence that young children interpret SI differently from adults. However, results have varied, and there is now mounting evidence that around six years of age, children are able to derive the pragmatic inferences associated with SI (Foppolo, Guasti, and Chierchia, 2012). Variability in results across studies could be due to factors such as data collection methods and language-specific differences. In order to add to the growing body of literature in a meaningful way, this research investigated the interpretation of sentences that include SI by Chitonga-speaking children (7-15 years old) in rural Southern Province, Zambia, who were notably beyond the key age of six. The results of this study provide valuable insight into the interpretation of SI in a Bantu language and suggest that the acquisition of pragmatic felicity with words on a scale follows the order of acquisition identified in previous research, but may emerge at a later age in this linguistic context.