Researcher: Zombie fads peak when society unhappy

 A researcher says widespread interest in the world of the undead isn't just a random fad.

Clemson University English professor Sarah Lauro says people are more interested in zombies when they're dissatisfied with society as a whole.

Lauro has been studying the concept of the "zombie walk," a mass gathering of people who dress in tattered clothing and stagger about like zombies. She says such events originated in Canada a decade ago.

Over the next few years, as the U.S. became embroiled in war in Iraq, Lauro says the concept gained popularity in this country and continued to grow.

She says that as of last year, zombie walks had been documented in 20 countries. Guinness World Records says the largest took place in 2010 in New Jersey, with 4,000 participants.