morning, and the memory gaps are filled out by the patient, often with those occurrences which the patient would like to have had occurred. In this way such delusions may be considered to be allied to the ideational type, those of wish fulfilment which were described above.
An amnesia may lead to a delusion or false belief regarding the locality of a given place. An excellent example of this has been described by Alzheimer. A Russian who had emigrated, and located in Frankfurt, was taken to a hospital, where he insisted that he was in Russia. He could not recall any of the incidents of his removal from Russia and the period of time between his emigration from Russia until his admission to the hospital was lost from memory. The most natural conclusion for the patient under these circumstances was that he continued to be in Russia. Such a disorientation may be considered to be a delusion due to the lack of recognition of dissimilarities.
Kraepelin cites a somewhat similar case, due, however, to a different kind of memory defect, which was described by Ganser. This patient was a boy who had been admitted to the Munich psychiatric hospital who insisted that he was in Vienna. He also believed that he had been asked to join a company for the development of the Sahara Desert, that he had been in London to consult with others regarding this, and had just returned to Vienna in a balloon. The whole story was bizarre and apparently without reason, until it was subsequently learned that the patient had borrowed practically the whole system of ideas from a novel which he had read some time previously. He had forgotten the fact that he had read the book, but he remembered the incidents, and since the incidents could not be given their proper setting he assumed that they had happened to him. In this case the defect of memory was a defect in the sense that previous occurrences were not properly located as to personality. The special incidents were suitably remembered, but the reference of them was erroneous.
Closely associated in character with the delusions which have just been described are others which the French call “déjà vu” and “dejà entendu.” These are conditions in which the individual experiencing them believes that he has had similar experiences in the past. In a perfectly new situation, in a place which he has never before visited, a person believes that he has been a visitor there at some previous time. Or words which are read in the newspaper or words that are heard are believed to be exactly the same as others which he has experienced in the past, not only with respect to the individual words or their combination, but also with respect to their context and their meaning as applied to him. These feelings of having already experienced such situations are frequently due to memory defects. But in these cases the memory defects are of quite a different character from those in the cases which have previously been described. In the condition of “déjà vu”
