From the link provided above by Sinwei:
51) Discussion on Demonic Realms
As indicated above, sometimes the Buddha Recitation practitioner sees marks and forms which could actually be demonic realms. These are instances where cause and effect do not correspond. For example, while visualizing the physical features of Amitabha Buddha, a practitioner may suddenly see the features of a beautiful woman. Another cultivator, diligently reciting the Buddha's name in the hope of seeing auspicious scenes of the Pure Land, may unexpectedly see a slum area, with men, women and domestic animals running back and forth in all directions. Yet another practitioner, hoping to see precious lotus blossoms in the Pure Land, suddenly sees a small cart instead. These are demonic realms, as cause and effect do not correspond.