"Several of my colleagues in camp who were trained in psychoanalysis often spoke of a "regression" in the camp inmate - a retreat to a more primitive form of mental life. His wishes and desires became obvious in his dreams.
What did the prisoner dream about most frequently? Of bread, cake, cigarettes, and nice warm baths. The lack of having these simple desires satisfied led him to seek wish-fulfillment in dreams. Whether these dreams did any good is another matter; the dreamer had to
wake from them to the reality of camp life, and to the terrible contrast between that and his dream illusions.
I shall never forget how I was roused one night by the groans of a fellow prisoner, who threw himself about in his sleep, obviously having a horrible nightmare.

Since I had always been especially sorry for people who suffered from fearful dreams or deliria, I
wanted to wake the poor man. Suddenly I drew back the hand which was ready to shake him, frightened at the thing I was about to do.
At that moment I became intensely conscious of the fact that no dream, no matter how horrible, could be as bad as the reality of the camp which surrounded us, and to which I was about to recall him."
Victor Frankl "Man's search for meaning"