1This investigation represents a repetition and extension of Poetzl's classical experiments on dream formation following the tachistoscopic presentation of pictures. In more than thirty experiments Poetzl's chief findings have been confirmed. It was shown that those portions of the exposed pictures which were excluded from conscious perception went to make up the manifest content of subsequent dreams.

2It was shown that a remarkable process of preconscious perception is involved in these experiments. This process is characterized both by extreme accuracy of registration and great distortion of the preconsciously perceived percepts.