A new study has revealed that the brain is genetically tuned to recognize faces and places. The study conducted on twins also indicated that the genetic basis of the brain's capability of recognizes places and faces is far better than other objects, like words.
The findings are some of the first evidence demonstrating the role of genetics in assigning these functions to specific regions of the brain.
"We are social animals who have specialized circuitry for faces and places, Some people are better at recognizing faces and places, and this study provides evidence that it is partially determined by genetics," said Arthur W. Toga, PhD, director of the Laboratory of NeuroImaging at UCLA School of Medicine.
Thad Polk, PhD, Joonkoo Park, and Mason Smith of the University of Michigan, along with Denise Park, PhD, at the University of Illinois at Urbana-Champaign, used a functional magnetic resonance imaging (fMRI) scanner tomeasure activity in the visual cortex of 24 sets of fraternal and identical twins.
The twins viewed several series of images: sets of people's faces, houses, letters strung together, and chairs, as well as scrambled images that served as a baseline measurement.
Prior studies had identified distinct regions in the visual cortex where different categories of information are processed, a sort of division of labour in the brain that handles information about people, for example, independently of that related to cars.
Polk's analysis of brain activity patterns from the twins suggests how the organization of these independent regions is shaped. By showing greater similarity in the brain activity of identical twins than their fraternal counterparts when processing faces and places, the results indicate a genetic basis for these functions.
Polk suggested that activity in response to words might be shaped to a greater degree by one's experiences and environment.
"Face and place recognition are older than reading on an evolutionary scale, they are shared with other species, and they provide a clearer adaptive advantage. It is therefore plausible that genetics would shape the cortical response to faces and places, but not orthographic stimuli," Polk said.
The study appears in the December 19 issue of the Journal of Neuroscience.