Was Shay artificially aged to become a teenager, or is this his natural age?

In the PC version of Broken Age (AKA Double Fine Adventure) there is a room on Shay's ship that contains mementos and keepsakes from his childhood, as well as various notes and documents. There is quite a bit of content from his childhood, but then the content jumps to when he was a teenager, and there are some cryptic notes about procedures or experiments being performed without any context given.

Does this indicate that Shay was put onto the ship as a child but artificially aged to be a teenager, and that his journey may only have been a couple of years long, or am I reading too much into this?