Such dreams have been designated as convenience dreams.
Dreams of urination can be considered as typical convenience dreams. In the morning, when the pressure of urine on the walls of the bladder becomes stronger, dreams build up a convenient explanation around that unpleasant stimulus. Our wish to urinate is either represented as gratified or we are shown the impossibility of gratifying it (no toilet, doors locked, people looking, etc.). Unless the pressure is absolutely unbearable, we generally sleep on, satisfied or discouraged by such convenience dreams.
Freud tells in his "Interpretation of Dreams" of a striking convenience dream of his and of a variation it underwent on one occasion: "If in the evening I eat anchovies, olives or any other strongly salted food, I become thirsty at night, whereupon I awaken. The awakening, however, is preceded by a dream, which, each time has the same content, namely that I am drinking. The dream serves a function, the nature of which I soon guess. If I succeed in assuaging my thirst by means of a dream that I am drinking, I need not wake up in order to satisfy that need. The dream substitutes itself for action, as elsewhere in life. This same dream recently appeared in modified form. On this occasion I became thirsty before going to bed and emptied the glass of water which stood on a chest near my bed. Several hours later in the night, came a new attack of thirst, accompanied by discomfort. In order to obtain water I would have had to get up and fetch the glass which stood on a chest near my wife's bed. I appropriately dreamt that my wife was giving me to drink from a vase, an Etruscan cinerary urn. But the water in it tasted so salty, apparently from the ashes, that I had to wake up."
On a chilly summer night a woman patient had the following dream:
"A man took me in a canoe to the middle of a lake and upset the canoe, saying: 'Now you belong to me.'"
The lake, the canoe upset and the man in the dream were associated with many conscious thoughts and memories of hers. But this was mainly a convenience dream, which endeavoured to explain away the chilliness of the night through an appropriate scene. When the unavoidable awakening took place it was dramatized, as it is in so many cases of awakening, through a fall accompanied by a certain fear of death.
