Some hens do seem to have a disconnect in their brains. A Splash Orpington hen, daughter of my own late rooster, Suede, is one. She was continuously broody but refused to sit on eggs, nor would she ever accept chicks. She sat under my friend's porch, had to be hauled out repeatedly. She would not break up, no matter what was done to her. This went on and on and on, literally months on end. After a very long time, she seemed to snap out of it, but would do it again. She recently passed away from multiple strokes, we both feel as a result of the damage done to her body over time of these prolonged and odd broody periods.
I myself had a hen who went broody, a Buff Orp, within one month of onset of lay and we didn't have a rooster at the time. We tried everything to break her up, literally got her off the nest by force to eat and drink, but she must not have been eating as we thought she was. About Day 20 of this nonsense, she had trouble standing, her head would list backwards, eyes glazed. On advice of a long time breeder, we squeezed vitamin E capsules into her mouth and forced water into her with a syringe. In a couple of days, she began to snap out of it, but without intervention, she would have died. She went on later to go broody one more time, hatched two chicks and insisted on taking care of the 25 chicks in the brooder pen (three weeks old at the time) in addition to her own. She lived to be 6 1/2 and never went broody a third time.
