12 September 2011
Study confirms Pill's memory altering effects
by Kate Melville
Women who use hormonal contraceptives such as the Pill experience memory changes where their ability to remember the detail surrounding an emotional event is reduced. The new finding adds to a growing list of cognitive functions that are believed to be affected by hormonal contraception.
"What's most exciting about this study is that it shows the use of hormonal contraception alters memory," said Shawn Nielsen, a researcher from the University of California, Irvine. "There are only a handful of studies examining the cognitive effects of the pill, and more than 100 million women use it worldwide." She stressed that the medications did not damage memory. "It's a change in the type of information they remember, not a deficit."
In the new study, appearing in the Neurobiology of Learning and Memory, groups of women either on the contraceptive or experiencing natural hormonal cycles were shown photographs of a mother, her son, and a car accident. The audio narrative differed; some in each group were told the car had hit a curb, while others were told the car had hit the boy and critically injured him.
One week later, all the women were given surprise tests about what they recalled. Those using hormonal contraceptives for as little as one month remembered more clearly the main steps in the traumatic event - that there had been an accident, that the boy had been rushed to the hospital, that doctors worked to save his life and successfully reattached both his feet, for instance. Women not using hormonal contraceptives remembered more details, such as a fire hydrant next to the car.
The findings could help lead to fuller answers about why women experience post traumatic stress syndrome more frequently than men, and how men remember differently than women. Men typically rely more on right-hemisphere brain activity to encode memory and they typically retain the gist of things better than details. Women on the pill, who have lower levels of hormones associated with female reproduction, may remember emotional events similarly to men.
Source: University of California, Irvine