Hygge, Evans, and Bullinger (2002) recruited four groups of children. Two of the groups lived near an airport that was just about to open, and the other two lived near an airport that was about to close. Those groups were further divided into children who were tested when there was aircraft noise present, and children who were tested when there was no aircraft noise present. The children read lists of difficult words, and the number of reading errors was recorded. (When the children lived near an existing airport, they performed much more poorly when noise was present. The same was not true of children who did not live near an existing airport.)