14 DAY TRIAL // Researchers at the Duke University Medical Center have recently conducted a new study on how the brain understands the stimuli it's being exposed to every day. The investigation revolved around attractive human faces, which bombard us every day from the computer and TV screens. The science group used an advanced brain-imaging technique to make out how the cortex responds to these pleasant stimuli, and also to understand how much value it places on them.
During the experiments, participants were asked to follow a sequence of faces on a computer screen, while hooked to a machine. The investigators were thus able to determine that the human brain actually conducts two different types of evaluation in parallel, one that gages the quality of the viewing experience, and another that determines what that certain individual would trade to see the pleasant face again. Full details of the new study appear in the February 16 online issue of the respected scientific Journal of Neuroscience.
“One part of the frontal cortex of our participants' brains increased in activation to more attractive faces, as if it computed those faces' hedonic (quality of the experience) value. A nearby brain region's activation also predicted those faces' economic value – specifically, how much money that person would be willing to trade to see another face of similar attractiveness,” says the director of the Center for Neuroeconomic Studies at Duke, Scott Huettel, PhD.
The expert is also an associate professor of psychology and neuroscience and the university, as well as the senior author of the paper. While the test subjects were assessing the attraction level of the faces they say, their individual levels of brain activation were measured using an imaging technique called functional Magnetic Resonance Imaging (fMRI). This method can basically provide scientists with a view of which brain areas activate (receive more blood flow) in response to a certain stimuli, and which regions are inactivated, or have their activity suppressed, by the same things.
“For this new study, we built on prior work from colleagues who showed that young adult males not only value the experience of seeing a female face, but will treat that experience like an economic good – they will trade experience for money in a predictable manner. We expect that the functioning of the brain's reward system is essentially similar between males and females. However, what sorts of stimuli seem attractive – whether an image of a face or some other social cue – may differ between the genders,” Huettel concludes.