Funciones ejecutivas: Un estudio de los efectos de la pobreza sobre el desempeño ejecutivo / Executive functions: A study about the impact of the poverty on executive performance

RESUMEN

La bibliografía acerca del impacto negativo de la pobreza sobre el desarrollo neurocognitivo se ha ampliado y profundizado en los últimos años. Sin embargo, la explicación acerca de las formas y mecanismos a través de los cuales actúa la pobreza, requiere un mayor estudio. En el presente artículo se describen y analizan los efectos de algunos mecanismos de la pobreza sobre el desarrollo de funciones ejecutivas tales como: el control de interferencia y planificación al inicio de la edad escolar. En el año 2005 se trabajó con una muestra de 80 niños de ambos sexos, de 6 a 10 años de edad que eran alumnos de primer año de la Educación General Básica (EGB), en una escuela incluida en el Plan Nacional de Mil Escuelas Bajo el Nivel de Pobreza. También se trabajó con un grupo control de 40 niños sin riesgo que asistían a una escuela de nivel socioeconómico medio. Se administraron pruebas para medir el control de interferencia y escalas de observación comportamental y de percepción del vínculo con respecto a cada padre. Se hallaron diferencias significativas en cuanto al desempeño ejecutivo entre ambos grupos. La percepción de control hostil de parte de la madre, del padre y la edad del niño, resultaron variables predictivas de la capacidad de planificación. Las diferencias significativas halladas entre los niños expuestos y no expuestos a la pobreza, son consistentes con una larga serie de estudios e investigaciones acerca de los efectos de esta y especialmente de su duración, sobre el desarrollo físico, neurológico, cognitivo y social del niño.

ABSTRACT

Recent published research on the negative impact of poverty on neurocognitive development has been broader in scope and has analyzed more in depth the issue. Infant malnutrition, inadequate medical care, exposure to stress and violence (Shore, 1997), weak speech stimulation and scarce organization of the environment are risk factors conditioning self regulation, as assessed in previous research (Musso, 2005; Ninio, 1980; Peralta de Mendoza, 1997; Wood, Bruner & Ross, 1976). Nevertheless, there is a need for further study of the mechanisms and various ways in which poverty exercises such negative impact. This work describes and analyzes the effects of some of the mechanisms present in poverty which impact on the development of executive functions such as: interference control and planning, at the beginning of schooling. The sample was conformed by 80 children, between 6 and 10 years of age, boys and girls, attending the first grade of General Basic Education (2005 cohort, in República Argentina), at a school included in the National Plan of a Thousand Schools below Poverty Level. The group deemed at risk by poverty displayed the following indicators: children with high levels of malnutrition, high percentage of students who repeat courses which accounts for the number of older children, high percentage of unemployed parents, and with low levels of schooling. A control group was used that was formed by children attending a city school, not part of the Plan of One Thousand Schools under the Poverty Line; their parents had finished obligatory or high level education, they were merchants, employees or professionals. The instruments applied were: Simon Says Game (La Voie, Anderson, Fraze & Johnson, 1981, see Zelazo, 1996) to assess the executive or response control through the use of a rule, The Hanoi Tower (two rings version) to assess planing, a Self report to assess the childrens´ perception of parental styles (mother / father version) (Richaud de Minzi, 2006), and the Behavioural Observation Guide for Children (Ison & Fachinelli, 1993) that provides a quick overview of type and frequency of behavior problem in the children, were administered. Significant differences in interference control and problem solving were found between children exposed to poverty conditions and children not exposed. The perception of a hostile parental control and the child's age, were predictive variables of the capacity to plan. A statistically significant influence was found for Control by Withdrawal of relationships by mothers for hyperactive behaviour [F (1, 23) = 5,422; p = .029], when considering extreme groups with respect to perception of attachment. In other words, children who perceive that their mothers attempt to control them by denying care, affect or attention, tend to show more hyperactive behaviour than children who do not perceive that kind of attempted control. In addition, a statistically significant difference was found between the groups with very low and very high hostile control by the father, as regards planning [F (3, 41) = 4,429; p = .041]. That is, those children who perceive more hostile control from the father, show lower performance in their capacity to plan. The significant differences found between children exposed to poverty conditions when compared with those that were not, are consistent with the findings from a long list of studies and research results on the effects of poverty, particularly the duration of the exposure to poverty, on the physical, neurological, cognitive, and social development of children. The poverty factors can influence neurocognitive development through multiple mechanisms and specific associations. This study discusses the main mechanisms which could be responsible for the results reported in this study, concluding with the findings regarding the complexity of the multiple relationships between mediating mechanisms for poverty and neurocognitive development.