Stress, poverty, and academic performance

In the latest issue of Psychological Science, Chen, Cohen, and Miller report that kids from low socioeconomic status (SES) families show elevated levels of the stress hormone cortisol. From their abstract:

Individuals with a low socioeconomic status (SES) are at increased risk for mental and physical health problems, and the relationship may be mediated by the stress hormone cortisol. Over a 2-year period, children from low-SES backgrounds had higher levels of cortisol than did those from higher-SES backgrounds. Children from lower-SES backgrounds reported greater perceptions of threat and more family chaos, both of which may raise cortisol levels.

This is a fascinating finding, and something I was expecting. We know that chronic exposure to stress hormones like cortisol can cause damage to key areas of the brain associated with learning and memory, most notably the hippocampus. We also know that children who come from low SES families tend to do poorly with regard to academic performance.

Given all of this, the next set of studies to focus on would be to examine the effects of current stressors on academic performance, as well as the role of chronic stressors. I would imagine one study where you had at least four groups:

Group 1: Low current stress and low chronic stress history
Group 2: Low current stress and high chronic stress history
Group 3: High current stress and low chronic stress history
Group 4: High current stress and high chronic stress history

The obvious hypothesis to test would be that Group 1 would perform best academically, and Group 4 would perform the worst. But the real interesting results would be in comparing and contrasting Groups 2 and 3. At the very least, I would think that these groups might perform equally bad academically, and fall somewhere between the performance measures of Groups 1 and 4. But it is also possible that Group 2 may have enough cortisol-related brain anomalies that their performance would be worse than that of Group 3.

At any rate, if the results of such a study were able to demonstrate clear effects of current stress and chronic stress, the next step would be to see if we could relate the detrimental effects of chronic stress to specific brain damage. Behaviorally, we could test hippocampal functioning with spatial navigation tasks. It might also be possible to use functional magnetic resonance imaging (fMRI) to study hippocampal activity in non-stressed and chronically stressed students. There are also a number of pharmacological manipulations that involve the enhancement or blockage of certain hippocampus-related functions. If chronically stressed and non-stressed students responded differently to these pharmacological manipulations, that would provide further evidence of hippocampal damage due to chronic stress.

Once a relationship is established, of course, we’d need to see if we could start coming up with interventions to help the children exposed to chronic stressors. At a minimum, I would think that families would need to be educated on what constitutes “stress”, and how stress can affect the lives of their kids.