Ageing causes changes to the brain size, vasculature, and cognition. The brain shrinks with increasing age and there are changes at all levels from molecules to morphology. Incidence of stroke, white matter lesions, and dementia also rise with age, as does level of memory impairment and there are changes in levels of neurotransmitters and hormones. Protective factors that reduce cardiovascular risk, namely regular exercise, a healthy diet, and low to moderate alcohol intake, seem to aid the ageing brain as does increased cognitive effort in the form of education or occupational attainment. A healthy life both physically and mentally may be the best defence against the changes of an ageing brain. Additional measures to prevent cardiovascular disease may also be important. […]
It has been widely found that the volume of the brain and/or its weight declines with age at a rate of around 5% per decade after age 40 with the actual rate of decline possibly increasing with age particularly over age 70. […]
The most widely seen cognitive change associated with ageing is that of memory. Memory function can be broadly divided into four sections, episodic memory, semantic memory, procedural memory, and working memory.18 The first two of these are most important with regard to ageing. Episodic memory is defined as “a form of memory in which information is stored with ‘mental tags’, about where, when and how the information was picked up”. An example of an episodic memory would be a memory of your first day at school, the important meeting you attended last week, or the lesson where you learnt that Paris is the capital of France. Episodic memory performance is thought to decline from middle age onwards. This is particularly true for recall in normal ageing and less so for recognition. It is also a characteristic of the memory loss seen in Alzheimer’s disease (AD). […]
Semantic memory is defined as “memory for meanings”, for example, knowing that Paris is the capital of France, that 10 millimetres make up a centimetre, or that Mozart composed the Magic Flute. Semantic memory increases gradually from middle age to the young elderly but then declines in the very elderly.