"And also with what happened in Japan, seeing pictures of people without homes could trigger reminders of Hurricane Katrina," said Emanuel Maidenberg, associate clinical professor of psychiatry and clinical coordinator for the UCLA Anxiety Disorders Program in Los Angeles.
People may also become numb to disaster after seeing the aftermath time and time again.
"The question is, does one become desensitized after seeing tragedy after tragedy? It starts to take on an unreal quality," said Nemeroff.
Even if that happens, experts say it's only temporary.
"With each new event, at least for the first few days, our radar gets lit up again," said Rego.
Despite the death and devastation caused by the onslaught of major disasters throughout the world, some say they can have some positive impact.
"I think it makes us more aware of the fragility of life and our own current security," said Dr. Redford Williams, director of Duke Universisty's Behavioral Medicine Research Center in Durham, N.C. "I think it might help us to be grateful for what we have."