What watching porn does to a woman's brain.

A study "showed that far less blood was sent to the primary visual cortex, while the women were watching the most explicit porn."

The same thing happens in the brain when a human conducts a non-visual task—like memorizing a list of words—while being shown some sort of visual "distractor" stimuli. Interestingly, when watching normal, non-smut films, extra blood is sent to the visual cortex.

Now, why would this be? Sex is nonvisual for women — that seems like the working theory. If so, porn movies don't make sense: watching causes not watching.