Brain scans of porn viewers

Researchers from the University of Picardie Jules Verne were curious about what happens in the brain to cause an erection when men are exposed to certain images. Specifically, they wondered whether "mirror neurons," are involved in the erection response. Mirror neurons fire both when you do something and when you observe that same thing being done by another. So Harold Mouras and his colleagues showed porn videos to eight men while scanning their brains. (The videos were mixed in with fishing documentaries and other footage that isn't erotic, er, to most people.) Meanwhile, they used a "penile plethysmograph" to determine when the men got erections and how hard they were. From New Scientist:
Interestingly, the volume of the erections correlated with the strength of activation in a part of the brain called the pars opercularis, which is known to display mirror neuron activity. Even more intriguing, the brain activation, say the researchers, precedes the penile response.

"The mirror neurons are like the command," says Mouras. "The activation comes before the erection." 'Bold' study

The study, says Mouras, is the first to suggest that mirror neurons are involved not only in observed actions, but in the "automatic" responses to those observations – in this case, erection.
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