2 claims in “developmental psychology, education”
The Hart and Risley study found long-term effects lasting beyond the initial three years: five years later (at approximately age 8), the vocabulary gap had expanded from the original 500 vs 1,000 words at age 3 to a gap in standardized test performance at third grade.
'Language nutrition' is the concept that the development of neurons and brain capacity is biologically dependent on language exposure, directly leading to the ability to read, which in turn leads to high school graduation and college education.