Objective: It is 50 years since Leslie Kiloh's paper titled "Pseudo-dementia" was published. The present article aims not only to honour the work and achievements of Professor Kiloh, but also to consider the impact and importance of that 1961 paper.
Conclusions: Kiloh presented vignettes concerning 10 patients, most of whom presented with depressive features. The term "pseudodementia" had been used previously. However, Kiloh's paper gave impetus to psychiatrists to focus on the potential reversibility of cognitive impairments that might be attributable to psychiatric disorders (depression, schizophrenia and conversion disorder among them). The historical context of the paper needs to be highlighted; it was written at a time when dementia was defined as being irreversible. Outcome studies and ongoing research have shown that cognitive deficits in cases of depression commonly cannot be fully reversed, and commonly herald emergence of an underlying progressive dementing disorder. Nevertheless, it is argued that the term has remained useful in fostering discussion of potentially treatable psychiatric symptoms, even in cases of progressive dementia.