Children’s memories of Hurricane Katrina faded after they lived through Hurricane Gustav, a new study has found.

The research, led by University of New Orleans psychology professor Carl Weems and published in the Journal of Experimental Psychology: General, found that overall, kids’ memories of a traumatic event fade after experiencing an event that’s similar but less stressful.

“This is a fairly substantial first-of-its kind finding,” Weems said. “We were able to confirm a promising line of laboratory research that suggests there may be an adaptive alteration of memories for traumatic events. That means when we experience similar events, in a less stressful way, our minds may re-interpret the past in a more positive light.”

Called reconsolidation, the theory had never been tested outside a lab before Weems and his colleagues studied New Orleans schoolchildren who lived through both Katrina in 2005 and Gustav in 2008.

Before Gustav, the kids’ Katrina disaster memories were consistent, regardless of age or gender, Weems found. After Gustav, however, memories of Katrina seemed to alter for children who had relatively positive experiences during the second hurricane.

Essentially, the positive Gustav experience diminished the Katrina memories. Weems discovered, however, that the kids who had negative experiences during Gustav still had strong memories of Katrina.

The findings suggested that children can be reliable reporters of experience following a major disaster. Research also shows that subsequent events of lesser trauma are important when applying the reconsolidation theory to traumatic stress, according to the publication.

“Forgetting negative aspects of past similar events may be adaptive in this context because, unlike during Katrina, the evacuation for Gustav was relatively successful, the levees held and the New Orleans area was significantly less damaged than during Katrina,” Weems said.

Katrina, one of the deadliest hurricanes in U.S. history, made landfall in southeast Louisiana on Aug. 29, 2005. The hurricane and resulting floods caused more than 1,800 deaths and an estimated $108 billion in property damage.

Hurricane Gustav made landfall in Haiti on Aug. 26, 2008, and in Louisiana on Sept. 1, prompting 3 million people to evacuate. It resulted in 153 deaths in the U.S. and the Caribbean and an estimated $4.3 billion in property damage in the U.S.