Nature vs. Nurture Debate: The Answer is … Both
Headlines suggest genes hardwire some people to be financial risk-takers, spiritual beings, or bad drivers. They even suggest genes determine who we vote for. But scientists don’t frame the debate as “Nature vs. Nurture.”
Experts believe both contribute to who we are as individuals and societies. Skokie resident Joan Chiao is one of the foremost researchers in this field called cultural neuroscience.
Her work at Northwestern University spans several disciplines to help untangle the interplay of genetics and culture. She uses brain scans, interviews, genetic tests and other population data to explore how biological and cultural forces give rise to everyday emotion and social interaction.
Professor Chiao is conducting a Science Café on May 19, 2010, at the Firehouse Grill in Evanston (750 Chicago Avenue) from 6:15-7:45 pm. The event is free and open to the public. Science in Society asked her for a preview.
What is cultural neuroscience?
It’s the study of how cultural values, practices, and beliefs give rise to biological phenomenon – and vice versa. We look at this in three different time scales: in the moment, across the growth and development of an individual, and across evolution.
What do you mean by “in the moment”?
I mean how culture affects biology during everyday activities. Examples of cultural neuroscience at work in the moment are common in advertising. Western culture values individual achievement and choices, so you see images of successful individuals in Western ads. On the other hand, Eastern culture values the group or family, so images of families dominate ads in these cultures. What’s intriguing is that when members of the corresponding culture see the images targeted at them, it activates the same part of the brain – the medial prefrontal cortex, which is associated with thinking about yourself. We think that’s why different ads elicit the same behavior (buying products) in different cultures.
You study how race, gender, and age influence perception, thoughts and emotion. Do you have favorite studies?
I have two. One is a study in which we looked at the role race plays in empathizing with others at a neural level. We showed people images of Hurricane Katrina victims who were either white or black, and asked them questions about how the pictures made them feel and how likely they would be to help the people in the pictures. We found that people were far more likely to share the suffering of others of the same race, and would be far more likely to help. This was true regardless of whether those viewing the pictures believed in racial equality.
My other favorite study is one in which we explored depression and anxiety in different cultures. We looked at populations in 29 countries and found the gene associated with depression and anxiety is much more common among individuals in China and other East Asian nations than in individuals in Europe and the other Western cultures. In fact, 80 percent of the population in Eastern cultures has the gene compared to 40 percent in Western cultures.
What’s surprising is that people in Eastern cultures exhibit far lower rates of the brain disorders associated with this gene. They have much less stress, anxiety and depression than their counterparts in the West. We think the cultural differences in Eastern societies developed to buffer them from their biological predisposition to anxiety and depression. In other words, societies that grew to place a high value on social support groups did so to help prevent the life-threatening events (like suicide) that they were at risk for. This demonstrates that evolution is operating on at least two levels: the biological one Darwin outlined that is well understood, as well as a cultural one we are only now beginning to appreciate.
Professor Chiao's Science Café, "The Cultural Brain" is on May 19, 2010 from 6:15-7:45 pm at the Firehouse Grill in Evanston (750 Chicago Avenue). The event is free and open to the public. Click here for more information.
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