Nov. 6 (HealthDay News) -- Do you remember the first time you smelled a type of flower? You almost certainly don't, but new research suggests that your brain might.

In the study, published online Nov. 5 in the journal Current Biology, researchers showed objects to adult study participants. They paired the objects with pleasant or unpleasant odors and sounds.

"We found that the first pairing or association between an object and a smell had a distinct signature in the brain," Yaara Yeshurun, of the Weizmann Institute of Science in Israel, co-author of the study, said in a news release from the journal's publisher. "This 'etching' of initial odor memories in the brain was equal for good and bad smells, yet was unique to odor."

At the same time, the researchers scanned the brains of the participants using functional MRI technology.

A week later, the researchers showed the same objects to the study participants and scanned their brains to see if there was a link to the sounds and smells.

The study participants were more likely to remember an association if the link was unpleasant. But there was more: A part of the brain connected to the sense of smell activated when they linked a smell to an object.

The researchers think there's something unique about the first time we smell something.

"We expected a unique representation of initial or 'first' olfactory associations, but did not expect that it would materialize even in cases where the behavioral evidence did not indicate a stronger memory," Yeshurun said. "In our paradigm, initial and later olfactory associations were remembered equally well, but only first associations had the unique brain representation."

The research could eventually help scientists boost memories, Yeshurun said. "Perhaps more importantly, it may help us generate methods to better forget early and powerful memories, such as trauma."

SOURCE: Cell Press, news release, Nov. 5, 2009