The Cost of Inaction for Young Children Globally: Workshop Summary (2014)

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The Science of Developmental Potential

The forum emphasizes an evidence-based approach to explore new and innovative science that can be translated into policies to improve the lives of children. Accordingly, the workshop opened with a discussion of new science in developmental potential. Individual speakers focused on the science of developmental potential and disability and illuminated how different factors such as nutrition, stress, enrichment, and cultural context affect that development.

THE TIMING OF INTEGRATED EARLY INTERVENTIONS: NUTRITION, STRESS, AND ENVIRONMENTAL ENRICHMENT¹

Michael Georgieff began his presentation by stating that one must consider the way in which the brain develops when designing interventions. Georgieff posited that an integrated approach is essential because neural, nutritional, metabolic, physiological, and behavioral biology form a linked multidimensional system. All behaviors emanate from the brain, he explained, which has a well-described development path. Rules must be applied to assess brain development and the impact of environmental factors (such as nutrition, stress, and environmental enrichment) on the developing brain.

The brain is inhomogeneous and composed of multiple subregions,

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¹ This section summarizes information presented by Michael Georgieff, University of Minnesota.

stated Georgieff. In addition, the brain consists of many areas and cell types, each with a different developmental trajectory. Some areas begin and end development during the fetal period, while other areas continue to develop through adolescence. As a result, the vulnerability of the brain to environmental factors depends upon the interaction of (1) the timing of an environmental deficit or enrichment; (2) the brain region requirement for a nutrient, its receptivity to enrichment, or its vulnerability to stress; and (3) dosage and duration.

Vulnerability changes through the life of a child, as described by Georgieff. For example, different brain regions have different iron requirements over time, and so a child is not equally at risk for iron deficiency throughout his or her life. The times of highest risk occur when there is high demand coupled with a strong lack of availability. Moreover, Georgieff pointed out that toxic stress is always a negative and can lead to an unhealthy brain structure. In stressful situations, dendrites shrink and behaviors become less efficient. Georgieff explained that the variables are interrelated: for example, stressed people do not absorb nutrients as efficiently. Conversely, poor nutrition gives rise to stress responses.

In noting that the brain is both plastic and vulnerable, Georgieff suggested that, on the whole, vulnerability outweighs plasticity. He also pointed out that it may be possible to reestablish plasticity in the brain, and that less rapid growth in regions of the brain does not mean that the change is immutable. Primary systems, including learning and memory, speed of processing, and reward, develop in the first 3 years of life; these primary systems provide the “scaffolding” for the later development of higher-order neural systems. Georgieff proposed aligning the timing and coordination of interventions based on differential sensitivity periods. This would be particularly helpful in resource-limited environments, because targeting sensitive developmental windows for providing integrated biological and psychosocial interventions will be most efficient in promoting the development of children.

Expounding on the idea of the importance of timing for interventions with young children, Georgieff used the example of nutrient supplementation on cognition. He stated that clinical data support the importance of nutrient supplementation at critical times, providing the specific example of iron (Christian et al., 2010). Fetal supplementation of iron improved memory, inhibitory control, and fine motor skills when the children were ages 7–9. Supplementation of iron later than the fetal period did not have an effect (Murray-Kolb et al., 2012).

Georgieff stated that, in general, early intervention results in better outcomes. He cited results showing that 6–12 months is a sensitive period for promoting secure attachment (van Ijzendoorn and Juffer, 2006); the early years of life are a salient time period for interventions to improve

quality of parenting (Bakermans-Kranenburg et al., 2003); and intervention during early years has long-term cognitive and academic benefits (Barnett, 2011; Engle et al., 2011). Follow-up interventions later in childhood have also proven effective (Reynolds and Robertson, 2003; Reynolds et al., 2001). He pointed out that adolescence remains a relatively unexplored area of brain change and offers an opportunity to catch up and solidify the scaffolding put into place as a young child.

In conclusion, Georgieff stated that early development (prenatal to 5 years) affects the developing primary brain structures, and it is difficult to make up this development later in life. He also pointed out that follow-up and follow-on interventions are critical, particularly for children who have multiple risk factors. In the discussion period, Georgieff noted the importance of finding early predictors of outcomes, such as likely models for success in education, employment, and social structure. He gave the example of autism and its late diagnosis. Although there are early indicators, many children, especially boys, are not diagnosed until age 3, and they miss early interventions during crucial periods of brain development.

DEVELOPMENTAL POTENTIAL AND CHILD DISABILITY²

Maureen Durkin defined a child disability, or developmental disability, as functional limitation(s) manifested in childhood because of impairments to the developing nervous system or other bodily systems. A disability can affect many aspects of development. She explained the causal pathways for learning and developmental disabilities, using a scheme to identify risk factors and interventions from preconception through early development with evidence-based proof of effectiveness (Durkin et al., 2007).

The early childhood development community tends to focus on optimizing conditions for children without disabilities, at the exclusion of children with developmental disabilities. There is little integration of developmental disabilities into early child development research and program development agendas, according to Durkin. Perhaps the rationale is that, with limited resources available, funding should not be “wasted” on children who will never achieve optimal development. Durkin argued that recent developments in human rights (both for children and for persons with disabilities) support the need for including children with disabilities in work related to the education and health of children. Durkin pointed out that the disabled are being recognized more and more as

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² This section summarizes information presented by Maureen Durkin, University of Wisconsin.

human beings with rights, instead of objects of charity. She specifically noted the United Nations’ Convention on the Rights of the Child (United Nations, 1989) and the Convention on the Rights of Persons with Disabilities (United Nations, 2006) as two activities that explicitly acknowledge the rights of children with disabilities.

The United Nations’ Millennium Development Goal 4 is to reduce by two-thirds the mortality rate for children under age 5 from 1990 to 2015.³ Durkin explained that significant progress has been made toward that goal; and as of 2011, child mortality had dropped by nearly half worldwide.⁴ Durkin pointed out that reduction in child mortality leads to an increased prevalence in disability, and she provided data from Bangladesh to support this claim (Khan et al., 2013).

United Nations Children’s Fund (UNICEF) currently plays the lead role in international monitoring and assessment of child disabilities. Data show that children in low- and middle-income countries are at the greatest risk for severe disabilities because of the lack of access to primary prevention and exposure to poverty, according to Durkin. However, there are relatively few data from around the world to confirm the prevalence of developmental disabilities in these countries owing to a lack of assessment tools, trained personnel, and funding to collect and monitor this information.

Durkin also pointed out that economic development does not lead to a decline in disability; in fact, the prevalence of child disability has increased with economic development in the United States (Halfon et al., 2012). As the prevalence of child disability has increased, the proportion of disabilities classified as “mental” has also increased. In the United States, most of the increase in the prevalence of child disability in recent decades has been from increases in cognitive and behavioral disabilities. Durkin cautioned that economic investment will not necessarily reduce disability numbers, at least in the short term.

Studies on the cost-effectiveness of interventions support selected interventions across primary, secondary, and tertiary levels (Durkin et al., 2006). Specifically, Durkin explained the results of a study that examined the cost-effectiveness and benefit–cost ratios of several interventions focusing on different aspects of developmental disability (Durkin et al., 2006). One of these interventions was folic acid fortification of the food supply to ensure optimal maternal folic acid levels before conception. The cost-effectiveness of folic acid varies around the world because of differences in cost and prevalence, but in all cases folic acid fortification

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³ See http://www.un.org/millenniumgoals/pdf/report-2013/mdg-report-2013-english.pdf for more information (accessed April 30, 2014).

⁴ Ibid.

is highly cost effective: the cost per disability-adjusted life years (DALYs⁵) averted ranged from $36 in Latin America to $160 in East Asia. A second intervention highlighted by Durkin was newborn screening for congenital hypothyroidism followed by targeted thyroid hormone replacement therapy to prevent the onset of disability. The benefit–cost ratio for this intervention ranged from 2 to more than 5.

Durkin concluded by noting that, at the population level, child disability is integral to child development and vice versa; society cannot make progress in either area without unifying them and putting them on the same agenda. Despite the existence of effective interventions, children in low- and middle-income countries are not likely to have access. This condition increases the risk for disability globally. She stated that, for a condition to become a global health priority, the condition must be common, severe, and changeable. She argued that disability satisfies all three conditions, and prevention of disability should be an international priority.

SOME CRITICAL GAPS IN THE CURRENT SCIENCE BASE OF DEVELOPMENTAL POTENTIAL⁶

Robert Serpell began by describing several developmental characteristics of humans: they are plastic and resilient; they rely heavily on caregivers in the early years; they are predisposed to live in social groups and to use language for communication; they have the capacity for reflection and innovation; they participate in culture and society; and they develop cultures particular to their community. Serpell explained that humans’ developmental niche consists of three dimensions to which humans adapt: physical and social settings, caregiving practices, and implicit theories held by caregivers (Super and Harkness, 1986).

According to Serpell, the International Child Development Steering Group (ICDSG) articles in Lancet (Engle et al., 2007; Grantham-McGregor et al., 2007; Walker et al., 2007) contain a political argument about social justice and economic inequalities. The group also made a technical argument grounded in science about the strategic benefits in prevention. To strengthen the argument, Serpell posited that the ICDSG exaggerated the degree of consensus within the community about what constitutes developmental potential and how to support its fulfillment.

The ICDSG supported an intervention package similar to the 1980s UNICEF strategy of growth monitoring, oral rehydration, breastfeeding,

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⁵ DALY is the sum of the years of life lost to premature death and the years lost to disability for people with a particular health condition.

⁶ This section summarizes information presented by Robert Serpell, University of Zambia.

and immunization (GOBI). The case was made that these were universally effective for infant survival, growth, and health. The ICDSG proposed that, in this new era, stimulation and caregiver sensitivity are universally effective causes of social and emotional competence in children. However, Serpell pointed out that there is no cross-culturally equivalent cognitive stimulation policy analogous to GOBI, and this policy is currently under critical examination. It is difficult to articulate and operationalize its principles across cultures, for three main reasons:

1. Environmental variations—Demands and affordances are different across cultures.
2. Theoretical biases—The criteria for validation of explanatory models in developmental psychology are influenced by culture.
3. Measurement challenges—Assessments depend on culturally specific practices.

Serpell noted that young Zambian children in lower-income families have a rich tradition of music, dance, and games, and they make their own toys. They receive little input from parents, but they do have significant input from siblings and peers, and they derive support from a socially distributed system of care. This local context may not adequately be considered in the ICDSG policy.

While models proposed by Western science are elegant, testable, and parsimonious, they have little usefulness if they fail to connect to the local realities, Serpell said. Research evidence does not currently exist to support that imported, culturally alien cognitive stimulation techniques are more supportive of children’s development than prevailing, local stimulation techniques. Serpell proposed that the design of appropriate, effective ECD services for African societies include the consideration of not only adverse economic conditions in rural and peri-urban neighborhoods, but also the strengths and limitations of local child-rearing practices, knowledge, and attitudes.

Measurement challenges, as identified by Serpell include the cultural relevance of standardized tests developed outside of the country or locale of interest. Standardized instruments have little adaptation to individual populations. If an external test is applied to a population for which it is not designed, the population will perform poorly. Serpell stated that most tests are grounded in Western practices, which disadvantage African test-takers. A specific example is in block design pattern reproduction, which is a Western-origin test that involves the manipulation of puzzles and blocks. African children tend to perform poorly, despite the fact that the main cognitive functions under assessment (such as visual discrimination, pattern reproduction, mental shuffling/rotation, and planning) tend to be

manifested in common, everyday behavior by African children, according to Serpell.

A study compared low-income, urban children in Zambia and England by presenting pattern recognition tasks in different media: paper and pencil, clay modeling, and wire modeling. As predicted by their ecocultural environments, English children scored much higher on the paper and pencil task, Zambian children scored much higher on the wire modeling task, and the groups did not differ in performance on the clay modeling task. The conclusion was that that the same underlying cognitive functions were only displayed when the test used a familiar medium. As a result, a clay modeling test was developed for the assessment of cognitive development in African children (Ezeilo, 1978; Kathuria and Serpell, 1998).

Serpell discussed three critical gaps in developmental science:

1. Language development in multilingual contexts—Serpell noted research evidence that multilingualism supports cognitive development (Bialystok et al., 2009; Cummins, 2000; Heugh, 2000; SRCD, 2013), but there is little evidence of how children learn language in a multilingual environment.
2. Child-to-child interactions as a source of cognitive development—Serpell argued that children taking responsibility for a younger child is not exploitative but rather is a respectful and effective way to give responsibility to a child in preparation for adult roles. He stated findings from research that showed such a system of practices promoted children’s prosocial values, peer-group cooperation, gender equality, and helping others (Serpell et al., 2011). However, a workshop participant cautioned that a distinction should be made for situations in which a child is forced to care all day for younger siblings and may not be receiving proper education as a result. Another participant noted that there is likely a gender differential to caregiving, with more girls than boys responsible for other children.
3. Socially distributed care and emotional security—Serpell noted that the hypothesis of maternal care as a biological survival mechanism (such as Bowlby, 1971) is a popular position. Less publicity has been given to alternative positions, such as that of Keller (2006), who showed that the goals of parenting as they relate to caregiving practices systematically differ in rural African societies from industrialized settings such as the United States. Serpell cautioned against applying a model of attachment from one culture to another.

Serpell stated that developmental science can enhance the design of social policies and professional practices by highlighting reductions in vulnerability of children in the presence of ameliorative intervention; individual and social factors that protect against poverty and its psychological impact; exceptions to the “developmental trajectory” postnatally given personal agency; and effective strategies to engage the community in the promotion of sociocultural change. Serpell concluded by suggesting a number of ways in which the community can move forward from provisional knowledge into responsible intervention, including

• Create partnerships in training in ECD.
• Launch feasibility projects incorporating and adapting indigenous cultural resources in ECD.
• Include cultural relevance in the criteria applied by accreditation bodies for approval of ECD services, institutions, and training programs.
• Challenge Western hegemony through the systematic study of cultural diversity.
• Integrate non-Western cultural resources into teaching resources for higher education in Northern, Western, and more industrialized countries.
• Bridge curricula for higher education between orthodox, Western, higher-educational practices and the demands of prevailing sociocultural contexts around the world.
• Institutionalize child development research at universities outside the Northern, Western, and more industrialized countries.
• Foster international partnerships in the design and delivery of professional training for ECD providers that emphasize the use of indigenous resources, cultivation of social responsibility, and respect for human rights.