Developmental delay in early childhood is associated with visual-constructive skills at school age in a Brazilian cohort

The nature of child development is essentially cumulative, and therefore, the first years of life are the basis for further development (Ali, 2013; Allen & Kelly, 2015). Child development is dynamic and involves the maturation of interrelated systems: cognitive, physical, and social-emotional skills (Casey et al. 2005). Early childhood is a time marked by rapid physical and neurological development and requires nutrition, stimulation, and appropriate health care for children to reach their full potential in terms of academic achievement and potential future earnings (Greenough & Black, 2013).

In general, children are referred to centers of treatment and diagnosis due to developmental delays, learning disabilities, or social interaction problems perceived by parents, teachers, or other professionals who follow the children into their routine. There are instruments to evaluate behavior and cognitive functioning in school-age children, including tasks with words and numbers, as at that age they are already able to understand language’s codes (Prelock et al. 2008). On the other hand, neuropsychomotor assessment is the main approach to evaluate cognitive functioning in early childhood, since those skills are developing faster in this phase, while the understanding of symbols is just starting (Theuer & Flores-Mendoza, 2003). The term “neuropsychomotor development” comprises motor skills, adaptation, socialization, and language (Dornelas et al. 2015; Le Boulch, 2001).

Neuropsychomotor development is crucial, since children develop language and other complex mental processes by the relationships they establish with the environment and active exploration through the manipulation of objects, the repetition of actions, and body self-control (Iverson, 2010; Levey & Polirstok, 2011). Progress in child development can be observed by the expression of initial motor acts and behaviors expected for each age getting successively more complex, according to the gradual maturation of the nervous system (Casey et al., 2005). Moreover, while children advance in independence and coordination, they become able to separately control each motor sequence and gradually coordinate these independent movements, making them more complex (Corso, 2007).

Throughout the development, fine motor skills merge with visual skills, allowing the assessment of problem solving based on visual-motor skills, an essential function of intellectual development (Accardo et al. 2008; Lipkin & Schertz, 2008). Visual-constructive skills require the coordination of fine motor skills with visual-spatial abilities and include not only the perception of objects and execution of movements but also planning and mental organization, essential capabilities to the development of more complex cognitive skills (Lanca et al. 2003).

Delayed neuropsychomotor development has a negative impact on children’s interactions in their environment, what may cause deficits in their performance of daily activities and further changes in the functioning of critical systems for learning, memory, and general reasoning (Hernandez & Caçola, 2015; Wendt et al. 1984). It was estimated that about 200 million children (up to 5 years old) across the world present delays in their development (Grantham-McGregor et al., 2007). In Brazil, it was reported that 3.3 % of the 3869 two-year-old children screened positive for suspected developmental delay (de Moura et al., 2010). Longitudinal studies have reported the relationship between neuropsychomotor delays and deficits on intelligence (Davis et al. 2007; Murray et al. 2007), language (Amaral et al. 2005), academic achievement (Taanila et al. 2005), and socioemotional skills (Bart et al. 2007). Individuals who have marked delays in reaching developmental milestones in early childhood periods are at higher risk for a subsequent diagnosis of learning disability or intellectual deficit (Murray et al., 2007; Murray et al., 2006; Taanila et al., 2005).

During early childhood, especially due to the sharp brain neuroplasticity, children’s experiences may have long-lasting effects on the development of mental processes (Greenough & Black, 2013; Skaliora, 2002). In this sense, it is important to investigate the cognitive processes since early childhood so that delays or difficulties can be predicted and effective interventions can be planned. Based on this assumption, this study compared the performance of children reported as developmentally delayed at 4 years old and typically developed children on IQ, visual-spatial memory, and visual-constructive skills at school age.

The findings from this study indicated that the neuropsychomotor development delay perceived at 4 years of age was associated with IQ and the development of visual-spatial abilities later, at school age. The skills developed in early childhood seem to be fundamental to the further development of intellectual abilities in the following stages, such as school age (Leisman et al. 2015; Mecca et al. 2012). Standard neuropsychomotor development consists of progressively refined coordination of motor skills with visual-spatial abilities, specially through environmental exploration, improved planning and mental organization, and cognitive skills related to the development of higher-order cognitive skills, such as memory and executive functions, later in life (Lanca et al. 2003). In terms of visual memory, it seems that there is a dynamic interaction between cognitive function and visual perception and visual-spatial skills during development. Studies with visual-agnostic children suggested that deficits in visual-spatial skills may have an effect on visual memory performance (Metitieri et al. 2013). In this study, it is possible that children from the developmentally delayed group have more difficulties in performing a visual memory task given their deficit in basic motor and perceptual skills early in childhood.

It is important to point out that the whole sample is essentially from low socioeconomic status families. Previous publications with this longitudinal data reported that socioeconomic conditions and maternal mental health were associated with language (Piccolo et al., 2012), memory and executive function performance, and stress (Piccolo et al. 2016). Studies have reported that environmental—such as socioeconomic status, home language environment, parental style, parental mental health—and biological factors—cortisol and neurotransmitter levels, for example—may influence the typical sequence of child development, affecting cognitive abilities (Brito & Noble, 2014; Johnson et al. 2016; Noble et al., 2015). The stimulation of sensorimotor abilities in the first years of life seems to be crucial for the development of subsequent cognitive skills (Hernandez & Caçola, 2015; Tierney & Nelson, 2009). Several factors may have an effect in cognitive development, such as low birth weight; respiratory, neurological, and cardiovascular disorders; neonatal infections; malnutrition; low socioeconomic status; and prematurity, for example (Avants et al., 2015; Greenough & Black, 2013; Handal et al. 2007). The more negative factors in the children’s life, the more likely the damages in their development (Evans & Fuller-Rowell, 2013).

The first years of life are the period of greater brain plasticity (Markham & Greenough, 2004; Wachs et al. 2014), and the activities carried out in this phase support the integration between the different sensory sources, facilitating the emergence of adaptive responses to different situations, which forms the basis for the acquisition of mental and social skills (Leisman et al., 2015). Children living in deprived environments are more susceptible to adverse environmental conditions such as toxins, chronic malnutrition, nutrient deficiency, and lack of stimulation, leading to a higher risk of neurological and behavioral disorders, such as learning disabilities and intellectual deficit later in life (Handal et al., 2007; Johnson et al., 2016). Given that the groups assessed in this study were composed of children from low SES families, the socioeconomic factors may have limited sensorimotor experiences in early childhood. It is hypothesized that these limitations in an extremely important period for child development, combined with limited access to materials and suitable conditions for the development of the child, could not be compensated for up to school age for this study’s sample. It has been pointed out also the need to deepen the study of environmental variables (Lipina & Segretin, 2015), as other factors such as language environment at home (Melvin et al., 2016), absence of a parent (McLanahan et al. 2013), or stress as a result of living in disadvantaged environments (Callaghan & Tottenham, 2016; Evans & Fuller-Rowell, 2013; Piccolo et al., 2016) may have short- and long-term effects in child development.

One can ask: if all children are from low SES environments, why do some of them have presented deficits but some of them have not? Some hypotheses were formulated to answer this question. First, there are genetic factors that may determine at least a significant amount of those cognitive skills and deficits (Krapohl et al., 2014), and it may vary from children to children. Then, there are other variables that can be involved such as distinct pedagogical practice approach from different schools (Bondy et al. 2007; Challen et al. 2014; Malti et al. 2011), parenting style (Karbach et al. 2013; Lugo-Gil & Tamis-LeMonda, 2008), and environmental nurturing (Avants et al., 2015; McEwen, 2012). Some mechanisms of resilience may underline these results as well (Chen et al., 2012; Hutz et al. 1996). Finally, all those hypothesized dimensions may be involved and impact on children development through a mechanism explored by social sciences called the “Matthew effect” or “accumulated advantage” (Mellard et al. 2012; Stanovich, 1986). According to this theory, individuals who have better developmental conditions develop better skills, which in turn improve their environment, creating a beneficial cumulative effect. On the other hand, those individuals from more disadvantaged environments who already present a deficit, specially a difficulty in the important dimension of functionality, may not be able to overcome these difficulties once the environment is not stimulating enough and the opportunities of better life conditions (such as high-quality schools and safe neighborhoods) are scarce, limited, or insufficient, creating a cycle of maladaptation that becomes harder to cope with.

Studies about the effect of early life experiences, its effects on development, and the mechanisms that underlie those associations still have a lot of questions to answer, and this research provides additional evidences in this sense. The strengths of this study include the analysis of a longitudinal sample, which allows inferring data on child development along different stages, although not causal relationships. In addition, this study contributes to the comprehension of how events that occur in the first years of life are essential for understanding the later development. Results from this study draw attention to the importance of early development evaluation to identify children with delays and start intervention as soon as those deficits are detected. The findings of this study have implications for intervention programs as well. First, it seems that the best strategy is to start the intervention early in childhood, as it was already reported in studies from social and economic sciences showing that early developmental delay prevention significantly reduces future costs in treatments (Belfield et al. 2006; Heckman, 2000; Reynolds et al. 2011). Second, it implies that interventions targeting children who grow up in disadvantaged environments may create opportunities for them to overcome those environmental limitations and achieve better cognitive outcomes.

It is important to mention that our findings can only indicate correlational association between the variables in those two different periods of children’s development. Although this study had a longitudinal design, we cannot infer casual effects of the variables from early childhood on the differences in visual-constructive skills later on at school age, since other variables (biological, behavioral, or socioeconomic) may contribute to the outcomes. Future studies aim to surpass some limitations of this work, expanding the sample size and investigating further factors of resilience and childhood development protection.

This study pointed out an important association between neuropsychomotor development at early childhood and children’s visual-constructive skills at school age. Those findings call attention to the importance of early evaluation of children’s development. Delays in child development trigger a complex and damaging cycle for the development of the child with such deficits. Consequently, it is necessary to evaluate and understand the cognitive processing in preschoolers in detail, taking into account family and school relationships, as well as its impact on the child’s adaptive functioning. Complete neuropsychological assessment enables early identification of children’s preserved and affected abilities. As a consequence, it is possible to delineate effective early interventions and likely help children reach better outcomes.