On one occasion, the Buddha said to the monks this:
"No other form do I know, O monks, that so persists in obsessing the mind of a man as the form of a woman. The form of a woman persists in obsessing the mind of a man.
Sometimes I am confused whether I am thinking thoughts, or whether thoughts enter from elsewhere. Because it is impossible to think a thought and recognize you are the thinker while you are thinking the thought.
Try to be aware of a your mind and at the same time try to recite something in your head. It doesn't work. At best it is an on-off switch (thought-thinker-thought-thinker...)