Poverty Poisons the Brain
Posted by dlende on February 18, 2008
Paul Krugman writes today that “Poverty Is Poison,” building off an article from the Financial Times that discussed last Friday’s session, “Poverty and Brain Development” at the American Association for the Advancement of Science. Krugman writes:
As the article explained, neuroscientists have found that “many children growing up in very poor families with low social status experience unhealthy levels of stress hormones, which impair their neural development.” The effect is to impair language development and memory — and hence the ability to escape poverty — for the rest of the child’s life. So now we have another, even more compelling reason to be ashamed about America’s record of failing to fight poverty.
The Financial Times article, “Poverty mars formation of infant brains,” provides some more detail about the impact of poverty through stress, inadequate nutrition and exposure to environmental toxins: “Studies by several US universities have revealed the pervasive harm done to the brain, particularly between the ages of six months and three years, from low socio-economic status. Martha Farah, director of the University of Pennsylvania’s centre for cognitive neuroscience, said: ‘The biggest effects are on language and memory. The finding about memory impairment – the ability to encounter a pattern and remember it – really surprised us’.”
Farah’s 2007 paper on “Socioeconomic gradients predict individual differences in neurocognitive abilities” relates: “Socioeconomic status (SES) is associated with childhood cognitive achievement. In previous research we found that this association shows neural specificity; specifically we found that groups of low and middle SES children differed disproportionately in perisylvian/language and prefrontal/executive abilities relative to other neurocognitive abilities… One hundred and fifty healthy, socioeconomically diverse first-graders were administered tasks tapping language, visuospatial skills, memory, working memory, cognitive control, and reward processing. SES explained over 30% of the variance in language, and a smaller but highly significant portion of the variance in most other systems.” (See her website for more info on this and other papers: http://www.psych.upenn.edu/~mfarah/ )
The Financial Times points specifically to the impact of stress: “Stress hormone levels tend to be higher in young children from poor families than in children growing up in middle-class and wealthy families, said Prof [Jack] Shonkoff. Excessive levels of these hormones disrupt the formation of synaptic connections between cells in the developing brain – and even affect its blood supply. ‘They literally disrupt the brain architecture,’ he said.”
Shonkoff has an on-line article on the interface of neuroscience, psychology and social policy in the context of child development, which I definitely recommend taking a look at. It includes a set of principles for understanding behavioral developmental and pediatrics, (1) Brains, skills and health are built over time; (2) Social, emotional and cognitive development are highly interrelated; (3) Brain architecture and human capabilities are built in a hierarchical, “bottom-up” sequence; (4) Brain plasticity and the ability to change behavior decrease over time; (5) Relationships are the “active ingredients” of early experience, and (6) The dynamics of stress in the developing child offer a promising model for thinking about causal mechanisms that mediate differences in learning, behavior and physical and mental health.
The research by Farah and Shonkoff is important, but I would add one important caveat. It is crucially important to not over-naturalize either poverty or the brain when thinking about this research. SES glosses over the complex political, economic and social practices that shape WHY some people are mired in poverty and others gather disproportionate wealth. Similarly, it is not “the brain” that ends up poisoned—that brain is connected to a body, both those are embodied in a person who develops in a complex realm of social relations, meanings, and practices.
In a concrete sense, the practices—the everyday life—of children growing up in poverty likely do not have the same rich scaffolding provided in other environments, coupled with the negative effects of stress. Moreover, the effect of stress often hides what the real phenomenon is: the systematic disenfranchisement of people. Disenfranchisement, the active denial of resources and the active pushing of negative forces, is more than stress. A lot more.
Krugman gets at some of this when he writes, “Living in or near poverty has always been a form of exile, of being cut off from the larger society. But the distance between the poor and the rest of us is much greater than it was 40 years ago, because most American incomes have risen in real terms while the official poverty line has not. To be poor in America today, even more than in the past, is to be an outcast in your own country.”
He continues, “Growing up in poverty puts you at a disadvantage at every step. I’d bracket those new studies on brain development in early childhood with a study from the National Center for Education Statistics, which tracked a group of students who were in eighth grade in 1988. The study found, roughly speaking, that in modern America parental status trumps ability: students who did very well on a standardized test but came from low-status families were slightly less likely to get through college than students who tested poorly but had well-off parents. None of this is inevitable.”
Krugman points to the importance of government initiatives and political will. Shonkoff highlights connections between research, policy and program development. I would add that efforts to stop disenfranchisement, the systematic denial of opportunities and the disproportionate thrust of our worst social consequences onto those least able to fend for themselves, and efforts to help people help themselves, working with the resources and skills and desires we all have, are central to any attempt at stopping the ways we poison ourselves. We humans create our inequality and our culture, and we need to think creatively how to engage our anthropological nature if we want to stop the poison.