Abstract
Research relating to three interrelated issues concerning cognitive deficit in the depressed elderly is reviewed. The issues are: the role of ageing in cognitive deficit associated with depression; whether the cognitive deficit is intrinsic to depression in the elderly or a secondary motivational effect; and the possibility of qualitative differences between the cognitive deficits seen in the depressed elderly and in senile dementia. Despite their fundamental importance, only the most tentative conclusions can be drawn with respect to any of these issues because researchers have either failed to recognise them or failed to appreciate the methodological problems involved in researching them.