Rags-to-riches stories are few and far between, and recent research shows evidence that children from low-income families are at risk of stunted cognitive functioning before they even start kindergarten.

Jennifer Suor, a Ph.D. candidate in clinical psychology, led the study that followed 201 low-income mother-child pairs. The children were brought into Mount Hope Family Center, where researchers took cheek swabs in order to measure and track cortisol levels (stress hormone) of the kids at age two, three, and four.

Suor explained in a press release:

"What we were interested in seeing is whether specific risk factors of children living in poverty might be related to children's cortisol levels. Then we looked to see if the hormone levels are predictive of significant differences in the children's ability to think."

She did add that moderate amounts of cortisol can “facilitate cognitive functioning.” Indeed, with the right amount, “it makes you rise to the occasion and it helps recruit important cognitive resources like memory and the ability to reason.” But she thinks that some of these kids are getting too much.

The researchers found that children with emotionally distant caregivers and living in an unstable home (e.g., moving and changing caregivers) at age two had elevated cortisol levels. But if the child just had family instability, cortisol levels were low. What's more, these levels “remained relatively stable over the three years."

Suor did admit that stress isn't the only factor that dictates cognitive functioning — "there are other environmental and biological factors. ... However, our research, as well as previous studies, has indicated that cortisol plays a role in cognitive functioning."

Suor said:

"There is a public awareness relevance to this study. We saw really significant disparities in the children's cognitive abilities at age four — right before they enter kindergarten. Some of these kids are already behind before they start kindergarten, and there is research that shows that they're unlikely to catch up."

Read more at EurekAlert!

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