Cocaine trumps food for female rats

SAN DIEGO — Presented with a choice between cocaine and food, female rats choose the drug while male rats go for the grub, a new study finds. The result may help clarify differences in addiction between men and women, scientists reported November 14 at the annual Society for Neuroscience meeting.

Kerry Kerstetter of the University of California, Santa Barbara and colleagues trained rats to press one lever to receive food or a separate lever to receive cocaine. Later, the rats were presented with the food lever and the cocaine lever at the same time.

At the time of the choice, all of the rats were hungry, so they should have been motivated to choose the food. Male rats clearly preferred the food. But female rats chose the cocaine over the food about half of the time. “Females and males seem to be very different when it comes to the incentive value of cocaine,” Kerstetter said.