From D&D Wiki
 Prison Life
For whatever reason, you have lived your entire life behind bars till just recently. Your being cut off from the world has given you -2 INT, but the constant beatings have made you watch your step, and has given you +2 WIS.
Benefit: +2 WIS
Drawback: -2 INT
Roleplaying Ideas: your character might have committed a crime worthy of a life sentence at a young age, or perhaps s/he was kept there for some other reason unknown to the player. you may have been released recently, or could have broken out. You may also be shocked when seeing the outside world for possibly the first time.