As aftershocks from the devastating March 11 earthquake continue to rock Japan, doctors say they been treating large numbers of people suffering from "earthquake sickness." Sufferers sometimes think the ground is shaking even when it isn't; other symptoms include dizziness and anxiety. Doctors liken the feeling of "phantom quakes" to the swaying sensation people feel when they step off a boat onto land.
The frequency of aftershocks has declined over the last month, but geologists warn that there will be more seismic activity than normal for up to a decade, the New York Times reports. There have been 400 aftershocks of magnitude 5.0 or greater over the last month, more than Japan experiences in a typical two-year period. Millions of people have downloaded smartphone applications that warn of quakes, and it is becoming common to see all the people in a restaurant suddenly look at their phones at the same time. (More Japan earthquake stories.)