Yesterday I posted on my other blog in Dutch new research that states that the influence of the genes on intelligence augments by the influence of the surroundings and culture:
“The counterintuitive finding that the most heritable abilities are the most culture-dependent abilities sheds a new light on the long-standing nature-nurture debate of intelligence.”
Comes in research number 3 that suggests childhood poverty and chronic stress may lead to problems regulating emotions as an adult:
“Childhood poverty has been linked to emotion dysregulation, which is further associated with negative physical and psychological health in adulthood. The current study provides evidence of prospective associations between childhood poverty and adult neural activity during effortful attempts to regulate negative emotion. Adults with lower family income at age 9 exhibited reduced ventrolateral and dorsolateral prefrontal cortex activity and failure to suppress amygdala activation at age 24. Chronic stressor exposure across childhood mediated the relations between family income at age 9 and prefrontal cortex activity. The concurrent adult income, on the other hand, was not associated with neural activity. The information on the developmental timing of poverty effects and neural mechanisms may inform early interventions aimed at reducing health disparities.” (source)
From the press release:
Our findings suggest that the stress-burden of growing up poor may be an underlying mechanism that accounts for the relationship between poverty as a child and how well your brain works as an adult,” said Dr. K. Luan Phan, professor of psychiatry at University of Illinois at Chicago College of Medicine and senior author of the study.
The study was conducted by researchers at UIC, Cornell University, University of Michigan and University of Denver.
The researchers found that test subjects who had lower family incomes at age 9 exhibited, as adults, greater activity in the amygdala, an area in the brain known for its role in fear and other negative emotions. These individuals showed less activity in areas of the prefrontal cortex, an area in the brain thought to regulate negative emotion.
Amygdala and prefrontal cortex dysfunction has been associated with mood disorders including depression, anxiety, impulsive aggression and substance abuse, according to the authors.
Phan said it is well known that the negative effects of poverty can set up “a cascade of increasing risk factors” for children to develop physical and psychological problems as an adult. But it has not been known how childhood poverty might affect brain function, particularly in emotional regulation. The ability to regulate negative emotions can provide protection against the physical and psychological health consequences of acute and chronic stress, he said.
The study examined associations between childhood poverty at age 9, exposure to chronic stressors during childhood, and neural activity in areas of the brain involved in emotional regulation at age 24.
The 49 participants were part of a longitudinal study of childhood poverty. Data on family income, stressor exposures, physiological stress responses, socio-emotional development, and parent-child interactions were collected. About half the participants were from low-income families.
Using functional magnetic resonance imaging, the researchers evaluated the participants’ brain activity as they performed an emotional-regulation task. Subjects were asked to try to suppress negative emotions while viewing pictures, using a cognitive coping strategy.
“This serves as a brain-behavioral index of a person’s day-to-day ability to cope with stress and negative emotions as they encounter them,” Phan said.
Perhaps the most important finding, Phan said, was that the amount of chronic stress from childhood through adolescence — such as substandard housing, crowding, noise, and social stressors like family turmoil, violence or family separation — determined the relationship between childhood poverty and prefrontal brain function during emotional regulation.
Abstract of the research:
Childhood poverty has pervasive negative physical and psychological health sequelae in adulthood. Exposure to chronic stressors may be one underlying mechanism for childhood poverty−health relations by influencing emotion regulatory systems. Animal work and human cross-sectional studies both suggest that chronic stressor exposure is associated with amygdala and prefrontal cortex regions important for emotion regulation. In this longitudinal functional magnetic resonance imaging study of 49 participants, we examined associations between childhood poverty at age 9 and adult neural circuitry activation during emotion regulation at age 24. To test developmental timing, concurrent, adult income was included as a covariate. Adults with lower family income at age 9 exhibited reduced ventrolateral and dorsolateral prefrontal cortex activity and failure to suppress amygdala activation during effortful regulation of negative emotion at age 24. In contrast to childhood income, concurrent adult income was not associated with neural activity during emotion regulation. Furthermore, chronic stressor exposure across childhood (at age 9, 13, and 17) mediated the relations between family income at age 9 and ventrolateral and dorsolateral prefrontal cortex activity at age 24. The findings demonstrate the significance of childhood chronic stress exposures in predicting neural outcomes during emotion regulation in adults who grew up in poverty.