The two brains look a lot alike. Scientists say that's because the brains of sex addicts and drug addicts respond in to their pleasure fix (sex and drugs) in similar ways.
Researchers recently demonstrated the similarities by showing self-admitted sex addicts pornographic imagery and then observing their brains using fMRI scans: , or function magnetic imaging -- a technique which measures blood oxygen levels in the brain.
The results showed that parts of the participants' brains that lit up when they witnessed pornographic videos were the same brain regions shown to be exceptionally active in drug addicts.
One in 25 adults are affected by sex addiction, or compulsive sexual behavior.
Though the researchers said the new study -- published this week in the journal PLOS ONE -- isn't proof that sex is addictive, it is further proof that sex addicts are affected by the problem in ways similar to drug addicts.
"The key features are that a person has to be using their addiction excessively, more so in an uncontrolled manner," said lead author Valerie Voon, a researcher at the University of Cambridge. "They feel they want to stop it, but they are unable to do so. The second component is it has a functional impact on their lives and causes significant distress."
"Studies like [this one] may be seen as another step towards our understanding [of] the similarities between excessive engagement in sex and excessive engagement in drug abuse," said study co-author Marc Potenza, a psychiatrist at the Yale School of Medicine.