I've heard the term "rage to master" to describe the ferocity with which a gifted child learns a topic. How do we (as a parent) distinguish this trait from the "special interest " type focus that can be associated with high functioning autism (formerly aspergers)?

My ds5 has made huge strides socially and emotionally in his first year of school, but we struggle with the amount of time he would like to spend learning whichever topic he has chosen for the month(s). He is my oldest, so I am not sure how "normal " his behavior is, or if smart kids just get hooked on an area.

He is currently interested/obsessed with presidents. He reads many books about them, but has a particular fascination for numbers/dates of the presidents. For each president, he knows: the month/day/year of birth and death, term of office, vice president(s) with often years of birth/death, First Lady often with year of birth/death, nicknames or given names, random facts. He can sort all of this information and apply it to different settings. Prior to this focus, he learned everything he could about the solar system ((including a crazy recollection for all the statistical data associated with each planet).

I am having trouble reconciling how this amount of numerical data could be stored in long term memory without there being something "wrong". When I voice concerns to his pediatrician, he doesn't seem at all concerned about it. Many parents on here may have raised a similar child, I would appreciate any feedback.