This study links chronic stress associated with childhood poverty to decreased brain functioning in key areas. It provides evidence that childhood stress can significantly impair a person’s working memory – a cognitive function essential for language comprehension, reading and problem-solving.
Researchers found that children who spent years in poverty displayed elevated levels of biological stress indicators, which corresponded strongly to decreased working memory. Young adults who grew up in poverty, for example, scored significantly lower on working memory tests than did those of similar age from middle-income families.
The findings suggest some biological basis, in addition to numerous social causes, for the academic achievement gaps among children of varying income levels. Free, five pages. www.pnas.org/content/early/2009/03/27/0811910106.full.pdf+html.