ABSTRACT

The link between ageing and disease in the brain is strong and in many instances the increased prevalence of brain disease in the elderly is taken as evidence that the disease is as a result of increasing age. Indeed, it has been suggested that there is a continuum between age-related pathology and diseases such as Alzheimer’s disease (AD), and that a decline in brain function and an increase in brain pathology are inevitable consequences of ageing. However, these assertions are, in many cases, unfounded and there is increasing evidence that brain pathology is not synonymous with brain ageing. There are a number of obstacles to being able to definitively separate ageing from disease. Some of these can be overcome with methodological improvements to research studies or with advances in technology, while others are inherent to the study of human disease. In addition, there are a number of theoretical issues to be considered when discussing the concept of brain ageing.