Katie has grown up sleeping with a fan running in her room since she was an infant. this provides white noise to drown out the television programs being watched by other family members who were still awake. in an effort to save electricity, her mother has started coming into her room and turning her fan off after she thinks katie is asleep. however, each time katie wakes up and asks for the fan to be turned back on. katie is selectively attending to certain kinds of information in her surroundings, which has been linked to the part of the brain.