Many years ago when I lived on a farm (1940's), we 'broke' brooding hens the old fashioned way - put them into a coop with no nest, or at least an eggless nest. Only food and water were available. After 2 to 3 days of confinement, their hormones adjusted and when they stopped making brooding sounds and motions, we'd release them.

Apparently, it is a clutch of eggs under a brood hen that activates her brooding phase.

Wow, you've got a broody Polish?! That's one determined hen! *L* Mine never go broody. Lots of my other hens DO, though, no clutch of eggs activation needed. :) Although it is imperative to not allow a broody that you are trying to break to have any eggs under her.

I've got several techniques for breaking broods here on my site, it might help:

http://jackshenhouse.com/VSChickHensBroodiesChicks.htm

In addition to what I've got there, you can try giving her a handful of ice cubes to 'brood'--the chill and the wet undercarriage can both work to dissuade her.

Velvet ~:>