Answer:
Gestalts theory was a big factor in solving problems. When it feels like your stuck and you can't figure out the solution to your problem, then it feels like a light bulb goes off in your head as if something just clicked.
More info at https://sites.psu.edu/psych256fa14/2014/11/26/i-just-cant-figure-it-out-the-story-of-insight/
Hope this helps!