Paediatricsmiddle twist
A 7-year-old girl's teacher reports that her schoolwork has fallen away this year and that she "drifts off". Her mother says that twenty or thirty times a day she stops mid-sentence and stares for a few seconds, then carries on where she left off; calling her name during one of these makes no difference and afterwards she has no memory of it. They are more frequent when she has been running around. Her hearing and vision screens are normal, she sleeps well and she does not snore. Which one of the following best explains her deterioration at school?