A recent study examining how the brain reacts to different types of image has found that women show a quicker reaction to erotic images than other image types. This is the first time that a difference in brain activity for erotic images has been found in women.
The research was led by neuroscientist Andrey Anokhin and used a technique that measures electrical activity from the brain by recording event-related potentials or ERP.
ERP is not very good at detecting which exact areas activity comes from, but can detect changes over very short periods of time (less than a millisecond). This makes it very good for determining differences in when the brain reacts.
Previous studies have found that men tend to show a stronger physiological response to erotic images than other images, as well as having larger areas of brain active when viewing such images.
Until now, no difference between erotic and non-erotic images had been found in women.
The study found that erotic images differently activated the mid part of the female prefrontal cortex (the red area in the image on the left) when compared to other images, within 185ms. Interestingly, this was regardless of how arousing or emotionally strong the images were.
185ms is an incredibly short time for the brain to differentiate between image types, and is almost certainly an automatic response. The prefrontal cortex is known to be involved in attention, and the authors suggest this activity reflects a vigiliance for socially relevant visual scenes.
When taken with the other research in the area, these findings suggests that men and women show differences in both where and when brain activity occurs when viewing erotic images.
However, it is still not clear what these differences might mean, and more extensive studies will need to be conducted to better understand this response.
It is also interesting that Anokhin and colleagues didn’t ask the female participants about sexual activity, orientation or a number of other things (such as stage in the menstrual cycle) that might affect reaction to erotic images.
It may be that these might have their own unique effect upon the new form of response reported in this study.