[Pseudodementias. Clinical and pathogenic problems]

Since the initial description by Ganser and Wernicke at the beginning of the century, two types of problems have appeared in the history of the concept of pseudo-dementia. The clinical ones have been at the root of careful descriptions of the pseudodemential syndrome by the Anglo-Saxon authors of the sixties, and have emphasized the psychiatric etiology and the reversible aspect of the disorders. The others are concerned with the pathogenic problems coming from pseudodementia and take in consideration -- on the basis of bringing together the clinical and neuropsychological sides with subcortical dementia -- the mechanisms that could be common to the physiopathology of the degenerating, demential and psychoneurotic disorders. This article analyses the concept of pseudementia in this double view, dwelling on the clinical and diagnostic problems.