Sleep on it, but only if it is difficult: Effects of sleep on problem solving

I was immediately reminded of Rich Hickey's talk, hammock driven development: http://blip.tv/clojure/hammock-driven-development-4475586.

It sounds like he was onto something with the waking mind being being prone to finding local maxima, but the background/sleeping mind being good for branching out and finding other solutions.

edit: Actually it looks like he cited scientific american talking about the sleeping brain finding relations between problems, I only remembered the bits about strengthening memory.

The item is behind a paywall.

Is there any chance we can get access to this article without having to pay?

thanks to hvass (the link is to a paywalled site), the basic idea is:

- some tasks require "lateral thinking". the example given is: what joins the words "lick", "sprinkle", "mine"? maybe lateral thinking is the wrong expression, but the idea is that the solution requires making connections from unrelated "semantic areas"

- people guess that the brain has a network-like approach where "activation" starts at nodes associated with the different concepts ("sprinkle", etc) and slowly spreads outwards, until, presumably, all three growing (glowing? ;o) areas meet at "salt".

- sleep helps for these tasks, but not for easier ones.

A related, long yet interesting, article is this one http://www.supermemo.com/articles/sleep.htm