Quick: who do you think are "on call" all day and all night? If you say emergency room physicians, you're only half right: nowadays, there are teenagers that stay up all night answering "emergency texts."

Brookline 10th-grader Ashley Olafsson sleeps with her cellphone under her pillow so she doesn’t miss “emergency’’ texts — “like if a friend broke up with her boyfriend.’’ Stephanie Kimball of Waltham, 14, is also available for urgent overnight correspondence, such as, “Hey, seeing if you’re awake.’’ Dedham ninth-grader Courtney Johnson gets as many as 100 texts while in bed. “I just don’t feel like myself if I don’t have my phone near me or I’m not on it,’’ she said.

Sure, all that middle-of-the-night communication leaves them tired, but as Olafsson explained, “It’s impolite not to respond if someone is coming to you with their problems.’’

With teenagers sending and receiving an average of 3,276 texts per month in the last quarter of 2010, according to the most recent statistics from the Nielsen Co., it’s no wonder that Michael Rich, director of Children’s Hospital Boston’s Center on Media and Child Health, is starting to see young patients who come in exhausted by being “on call’’ or semi-alert all night as they wait for their phones to vibrate or ring with a text.

He and his patients’ parents were initially baffled by the children’s increased sleepiness because bedtimes hadn’t changed, he said. “Who would think to ask a kid, ‘Do you sleep with your phone under your pillow?’ To us, it sounds like torture.’’

Yes, that's right: the average teenagers send and receive 3,276 texts per month! Link