When young men were shown erotic pictures, they were more likely to make larger financial gambles than if they were shown a picture of something scary, such as a snake, or something neutral, such as a stapler, university researchers reported.

The arousing pictures lit up the same part of the brain that lights up when financial risks are taken.

"You have a need in an evolutionary sense for both money and women. They trigger the same brain area," said Camelia Kuhnen, a Northwestern University finance professor who conducted the study with a Stanford University psychologist.

Their research appears in the current edition of the peer-reviewed journal NeuroReport.

The study involved only 15 heterosexual young men at Stanford University. It focused on the sex-and-money hub, the V-shaped nucleus accumbens, which sits near the base of the brain and plays a central role in what is experienced as pleasure.

When that hub was activated by the erotic images, the men were far more likely to bet high on a random chance game that would earn them either a dollar or a dime. Each man made more than 50 gambles under brain scans.