orking memory. The go-no go task and the orthographic and semantic verbal fluency tasks were used as indicators of the latent variable executive functions inhibitory control component. The latent variable verbal memory was composed of the following tasks: semantic memory, episodic memory immediate recall and visuoverbal episodic memory.
Once the literature has affirmed that there are differences in the contribution of SES to the different ages, we made the structural models by age range 6—7, 8—9, 10— The estimated coefficients are reported in Fig. The estimated coefficients are reported in Figs. The results show a moderate effect of SES and specifically parental education mainly maternal education on the performance in memory working memory , language and executive functions, especially for younger children from 6 to 12 years old.
The children with lower SES had lower performance regarding IQ, verbal episodic and semantic memory, working memory, written language, visuoverbal memory and inhibitory control tasks than those with higher SES. The findings of the present study are consistent with those from other studies that have demonstrated the contribution of SES to cognitive performance at different age ranges, especially in younger children Blair et al.
In fact, the magnitude of the relationship between SES and the identified factors were similar to other studies conducted in other contexts, like US and Canada Lupien et al. In the early years of childhood until school age, the socioeconomic status is a major factor since it may limit the conditions of the environment, what impacts on stimulation, access to materials and activities that favor cognitive development, presence of parents or caregivers and willingness to engage in activities with the child Forns et al.
Cognition, in general, and more specifically, memory, language and executive functions, seem to be more affected by the socioeconomic environment, due to its prolonged development — at a neuroanatomical level —, which may lead to increased susceptibility to environmental differences Noble et al.
Besides, SES is strongly related to other environmental aspects such as maternal depression and the amount of time spent by parents in activities with their children Piccolo et al. Our results showed that SES effects on cognition decline after nine years old. Lupien et al. In this case, the neuropsychological performance would be influenced by social interactions with peers and teachers at school.
In this perspective, the school system — that supposedly give the same resources for all students — and living in other spaces with another people, associated to children character as resilience , could equalize the performance of children from different socioeconomic contexts.
This characteristic would be associated with reduced physiological risk in low childhood SES individuals, helping them to deal with risks environments Chen et al. In the present study, both the SES and specifically parental education showed independent effects, on IQ. The greatest effects were observed in younger children up to nine years old. Studies of twins and adopted children provide evidence that genetic and environmental factors impact on general intelligence g factor and that a substantial part of the variation of cognitive ability in adulthood is explained by genetic variations Blair A model proposed by Eaves et al.
The continuity of cognitive performance over time and the increase in heritability with age reflect the cumulative long-term effects of a single set of genes expressed throughout development.
The quality of the shared environment changes from family to family over time appears to exercise a long-term effect on cognitive development Eaves et al. The acquisition of written language continuously improved with new skills, as the individual grows and it is totally dependent of the interactions with the environment Finkbeiner and Coltheart that provides stimuli and experiences that are essential for this development as a primary means of social interaction Kim ; Peeters et al.
Low SES chi