There is a high degree of overdetermination in the need for and choice of a screen memory. This investigation was initiated in order to understand a woman's repetitive associations to a filmed fairy tale throughout her analysis. It was determined from the associations preceding and following The Wizard of Oz that the film served as a screen memory to avoid experiencing the inner conflicts fixated by a traumatic childhood event—separation from the mother.

In addition to the painful experience of loss, the event was traumatic because of its revival of incestuous and aggressive wishes and their accompanying affects. The energy directed against experiencing the painful affects associated with the event led to the formation of a screen memory. This displaced memory had to be associatively similar to the repressed images. The choice of a particular film to serve as a screen memory was especially suitable