Tuesday, July 28, 2015
Your poverty is in your brain
We sort of knew that already. The correlation between low IQ and poverty is well-attested. The latest journal article below however takes the story a bit further in that it identifies which brain regions are responsible. Certain areas of poor people's brains are actually shrunken! The authors seem to have frightened themselves by their boldness, however, as they have tacked a totally illogical conclusion on to their findings.
If poverty is a result of the shrunken brain you were born with, does it not follow that there is not much you can do about it? The authors below avoid that conclusion. Instead they say that poor households "should be targeted for additional resources aimed at remediating early childhood environments". An hereditary problem can be fixed by changing the environment? That's a pretty good Non Sequitur as far as I can see.
It's not totally daft in that genetics accounts for only about two thirds of IQ. There are some other influences that have an effect. But all the research shows that family environment is NOT part of those other influences on IQ. It's jarring but that is what all the twin studies show. So the hairy lady and her colleagues below are just ignoring the evidence. But they need to in order to sound nicely Leftist about it all.
Footnote: The authors of course avoid the term "IQ" like the plague but the standardized tests of academic achievement they used are little more than IQ tests and correlate highly with acknowledged measures of IQ. So their findings show that IQ, income and brain development all cluster together.
Association of Child Poverty, Brain Development, and Academic Achievement
By Nicole L. Hair et al.
Importance: Children living in poverty generally perform poorly in school, with markedly lower standardized test scores and lower educational attainment. The longer children live in poverty, the greater their academic deficits. These patterns persist to adulthood, contributing to lifetime-reduced occupational attainment.
Objective: To determine whether atypical patterns of structural brain development mediate the relationship between household poverty and impaired academic performance.
Design, Setting, and Participants: Longitudinal cohort study analyzing 823 magnetic resonance imaging scans of 389 typically developing children and adolescents aged 4 to 22 years from the National Institutes of Health Magnetic Resonance Imaging Study of Normal Brain Development with complete sociodemographic and neuroimaging data. Data collection began in November 2001 and ended in August 2007. Participants were screened for a variety of factors suspected to adversely affect brain development, recruited at 6 data collection sites across the United States, assessed at baseline, and followed up at 24-month intervals for a total of 3 periods. Each study center used community-based sampling to reflect regional and overall US demographics of income, race, and ethnicity based on the US Department of Housing and Urban Development definitions of area income. One-quarter of sample households reported the total family income below 200% of the federal poverty level. Repeated observations were available for 301 participants.
Exposure Household poverty measured by family income and adjusted for family size as a percentage of the federal poverty level.
Main Outcomes and Measures: Children's scores on cognitive and academic achievement assessments and brain tissue, including gray matter of the total brain, frontal lobe, temporal lobe, and hippocampus.
Results: Poverty is tied to structural differences in several areas of the brain associated with school readiness skills, with the largest influence observed among children from the poorest households. Regional gray matter volumes of children below 1.5 times the federal poverty level were 3 to 4 percentage points below the developmental norm (P less than .05). A larger gap of 8 to 10 percentage points was observed for children below the federal poverty level (P less than .05). These developmental differences had consequences for children's academic achievement. On average, children from low-income households scored 4 to 7 points lower on standardized tests (P less than .05). As much as 20% of the gap in test scores could be explained by maturational lags in the frontal and temporal lobes.
Conclusions and Relevance: The influence of poverty on children's learning and achievement is mediated by structural brain development. To avoid long-term costs of impaired academic functioning, households below 150% of the federal poverty level should be targeted for additional resources aimed at remediating early childhood environments.
JAMA Pediatr. Published online July 20, 2015. doi:10.1001/jamapediatrics.2015.1475
Posted by John J. Ray (M.A.; Ph.D.).