ABSTRACT
References 368
Alterations in cognitive functioning in the absence of dementia have long been considered a normal aspect of ageing-related brain changes. Affecting principally episodic verbal memory, such changes are generally distinguished from neurodegenerative disorders by their far slower progression, their lesser impact on ability to perform activities of daily living, and the relative sparing of linguistic and visuospatial functions. Increased interest in the nature and long-term prognosis of ageing-related modifications in cognitive performance has now led us to question to what extent they may be considered ‘normal’. The past 50 years have seen numerous attempts to define these subclinical alterations in cognitive functioning and to establish their aetiology with greater precision than the general notion of ‘ageing brain changes’ to which they have formerly been attributed.
