Johnny Logic passes along the answer to some­thing that I’ve been won­der­ing about a long time:

The “click” of com­pre­hen­sion trig­gers a bio­chem­i­cal cas­cade that rewards the brain with a shot of nat­ural opium-​​like sub­stances, said Irv­ing Bie­der­man of the Uni­ver­sity of South­ern Cal­i­for­nia. He presents his the­ory in an invited arti­cle in the lat­est issue of Amer­i­can Scientist.

I feel kind good, know­ing that. Makes sense. Yeah!