Being poor is expensive. It can cost you access to health care and education. Because it can cost you access to transportation, it can also cost you access to healthier and lower-cost foods. The list of the high costs of being poor is long, but a cost that gets overlooked is the damage poverty does to our brains.
That cost is paid mostly by children. Controlling for factors like ancestry and health, research shows brain differences between low- and high-income children. The earlier in life you experience poverty and the longer you live in poverty, the worse the effects are likely to be.
Why? Among many contributing factors, a major reason is the environment in which poor children grow up. Stressful environments can hurt our ability to develop the skills that help us think, learn, plan, focus, develop strong vocabularies, synthesize abstract concepts, and succeed in school. In fact, our preschool home environment predicts how we’ll do in first grade better than either the quality of the classroom or the child care we received. Research suggests that stress alone explains the link of poverty to a poor working memory.
When we're stressed, the stress hormone cortisol floods many parts of the brain, including the part that's vital to learning conceptual information, forming memories, and regulating the stress response. With constant, excessive stress, the brain becomes overloaded and—eventually—damaged, which can impair memory and learning. The damage is worse in people living with PTSD, but it's also apparent in “low socioeconomic status” people, who predictably have higher levels of cortisol.
Growing up poor means you’re more likely to grow up in a neighborhood where there are more threats, which means more stress responses. According to the federal Bureau of Justice Statistics, “Persons in poor households at or below the Federal Poverty Level … had more than double the rate of violent victimization as persons in high-income households.” When that’s where you grow up, you learn to be on the watch for threats, respond more often to threats, respond more intensely to threats—as a matter of survival—with the consequence of a cycle of constant anxiety and altered brain function. As one community leader told me not long ago, the kids coming from low-income neighborhoods “are suffering PTSD.”
Not only do the poor endure these stress reactions more often, the stress response is more intense and lasts longer. When poor people, people who were once poor, and rich people are shown pictures of threatening faces, the stress-response part of the brain in poor people and people who used to be poor will be more highly activates and stay active longer. In other words, the tough spots in life are harder on you if you’re poor or grew up poor.
We recognize that being born into poverty puts you at high risk for a lot of bad things—higher costs of living, poor access to health care, substandard education, unsafe places to play, poor diet, high exposure to pollution, and parents who don't have time to read to you at night—but it’s worse than expected, because growing up poor many change your brain in ways that hurt your chances of escaping poverty.
In a twist of bitter irony, the one thing that has reduced poverty in the US is now under attack. Poverty has fallen by as much as 40% since the 1960s, thanks almost entirely to government anti-poverty programs. Without those programs, poverty would have increased over that period. Cutting them as currently proposed will be counter-productive and unimaginably costly to us all.