Miércoles 23 de Mayo de 2007, Ip nº 192

Can culture dictate the way we see?
Por Roxanne Khamsi

Culture can shape your view of the world, the saying goes. And it might be more than just a saying: a new study suggests that culture may shape the way our brains process visual information.

Researchers found that the brains of older East Asian people respond less strongly to changes in the foreground of images than those of their Western counterparts. They suggest this difference is due to an increased emphasis on the background, or context, of images in some Asian cultures.

Denise Park of the University of Illinois in Urbana, US, and her colleagues recruited 37 young and elderly volunteers within their community, as well as people from similar age groups in Singapore. The younger participants in the study had an average age of 22 years, while the older participants averaged 67 years.

The subjects each viewed a series of 200 pictures while their brains were scanned using functional magnetic resonance imaging (fMRI). The researchers varied either the foreground or background of the images (see right) to see if responses varied between the groups.

Age and culture
The researchers found expected differences between the age groups. There was a lower response by the hippocampus – a brain region which seems to help the mind connect a particular object to its background – among older subjects in both groups compared with their younger counterparts.

But the team also found a smaller response in a brain area involved in object recognition among elderly East Asians compared to the elderly Westerners. This occurred when the two groups viewed images with similar backgrounds but varying foreground objects. The brain region involved is called the lateral occipital region.

Importantly, they found no significant difference in the response of this particular visual processing region among young people in the US and Singapore. This, the team says, supports the idea that, over the course of decades, culture shapes how the brain perceives images.

"Their findings are convincing and encouraging," comments neuroscientist Moshe Bar at the Harvard Medical School in Boston, Massachusetts, US. "There are other demonstrations of environment-dependent visual development, but this one is very original in its focus on cultural effects."

Brain sculpting
The researchers note that previous studies tracking eye movement have found that East Asians are more likely than Westerners to pay attention to the background of a picture.

Park says her new findings, along with her earlier brain scan work that focused only on elderly volunteers, are "the first studies to show that culture is sculpting the brain".

However, some experts contacted by New Scientist say the results fail to prove that culture is the primary reason for the differences in brain response between elderly people in the US and Singapore. They say that there are numerous other factors correlated to culture that might explain the divergence.

Journal reference: Cognitive, Affective, and Behavioral Neuroscience (vol 7)

  04/05/2007. New Scientist Magazine.