Well, expectancy violation/mismatch is a reliable stressor down to the mesolimbic-corticostriatal level[1], so maybe that's that.

In any case, thank you for re-enabling it. I'm sure many future readers would thank you too.

[1] See for instance Box 2 in Proulx et al. 2012 (http://www.michaelinzlicht.com/wp/wp-content/uploads/downloa...).

Thank you Chris - I realized you could click through after I posted but I think it's good to zoom in and look at the parts while reading the text.