关键词: 贫困, 社会经济地位, 执行功能

Abstract: Poverty has negative effects on individuals’ physical and mental health. Due to the lack of material resources and environmental stimulation, the cognitive ability of individuals living in poverty will be impaired, especially their executive function. Executive function is a series of advanced cognitive processes closely related to attention, including working memory, cognitive flexibility and inhibitory control. This paper firstly mainly introduces the behavioral evidence that poverty affects executive function. Secondly, it analyses the correlation between poverty and the brain area related to executive function, namely the prefrontal lobe. The third one is the pathway that poverty indirectly affects executive function. From the perspective of cognitive plasticity, this paper believes that future research should pay more attention to the cognitive training of poor individuals, so as to compensate for the differences in cognitive ability between the poor and those with higher socio-economic status, which is of practical significance. The effect of poverty on executive function exists in infancy, childhood and adulthood. The result of behavioral experiments shows that poverty is negatively correlated with infants’ executive function performance, and poverty predicts their executive function level in early childhood. Poverty affects the executive attention of children, primarily in relation to attentional control and filtering irrelevant information. Taking adolescents as subjects, the study found that the poor group performed significantly lower on working memory tests and cognitive control tests. For adults, the results were similar. With the help of neurobiological methods, the techniques of event-related potential (ERP) and functional magnetic resonance imaging (fMRI) are used to explore the neural mechanism of poverty affecting executive function, and it is found that poverty is related to the structure of the individual's frontal lobe. Poor children have a smaller volume of gray matter in the frontal lobe, and their development lags behind. Lower family income is associated with smaller prefrontal surface area in children. Poor adolescents may have thinner frontal lobes due to a lack of cognitive stimulation. Poverty affects prefrontal function more than any other area of the brain. Poor children have difficulty in selective attention. When performing functional tasks, poor individuals and the non-poor have different ways of invoking resources in the frontal lobe. Poor individuals need to use additional compensation resources to monitor and inhibit responses to distractive stimuli, showing a pattern similar to that observed in patients with prefrontal lobe damage. Poverty indirectly affects an individual’s executive function through mediating variables such as stress, cognitive deprivation, and passive parenting. Current studies have fully demonstrated that stress and cognitive stimulation are proximal factors of poverty affecting executive function. Future research should focus on the moderator variable of poverty influencing executive function (such as self-affirmation and self-regulation) to buffer the negative effects of poverty on cognition. At the same time, a comprehensive model of poverty’s impact on executive function should be established (for example, duration of poverty, etc.), so as to make certain the possible causal relationship between poverty and executive function in a more comprehensive and in-depth way. More importantly, based on the plasticity of executive function, future studies should conduct more cognitive interventions for poor people. They transfer the results of cognitive training to their lives to help them perform better in work and study.

Key words: Poverty, Socio-economic status, Executive function