[nick_ok]

the word you are looking for is insight problem. Insight problems are problems in which people unable accurately predict their progress. As in if you asked someone to continually report their progress on a problem as they attempted to solve it they would say something like, "0% 0% 0% oh I'finished". Insight problem solving is a topic of significant interest in cognitive science right now and most recently it was found that applying a small amount of electric current to the right side of the brain greatly increase our capacity for insight problem solving. It is pretty dope.

[Camillo]

How much current? Do you think it would be doable to make a "thinking hat" to wear at job interviews?

[nick_ok]

This all came to light in 2011 so pretty recent. Also not only may it be possible, but the term 'thinking cap' has already been used to refer this very invention, namely transcranial direct current stimulation (tDCS). If you are interested check out this article, http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjourna... However I would not get your hopes to high up. It is unlikely that prolonged exposure would be particularly healthy and i imagine you would get diminishing returns.