How the human brain perceives nudity is boosted at an early stage of visual processing, researchers say, and that ability may be tied to mating.
Most people are attracted to pictures of nude or scantily clad bodies, the Finnish team note. Previous brain imaging studies have pinpointed areas in the brain that specialise in detecting human bodies in the environment but it wasn't known whether the brain processes clothed and nude bodies in different ways.
In this study, Jari K. Hietanen, of the University of Tampere, and a colleague monitored the brain activity of volunteers as they looked at pictures of men and women who wore everyday clothes or swimsuits, or were nude.
Female vs. male
The results showed that the brain processes pictures of nude bodies more efficiently than pictures of clothed bodies. Males' brain responses were stronger for nude females than nude males, but females' responses to nudity weren't affected by the gender of the bodies.
The study also found that the nude pictures were more sexually arousing than the other types of pictures, according to the report published in the journal PLoS One.
In a news release from the Academy of Finland, the researchers said the findings show that the brain boosts the processing of sexually arousing signals, which could help identify potential mating partners.
"The visual processing of other people's nude bodies is enhanced in the brain," the study authors wrote in the report. They add that this "is possibly beneficial in identifying potential mating partners and competitors, and for triggering sexual behaviour."
(HealthDay News, November 2011)