Читать книгу Pathy's Principles and Practice of Geriatric Medicine - Группа авторов - Страница 87

As discussed above, cognitive function is a major component in the psychological well‐being of older adults. Before turning our attention to abnormal cognitive ageing, we first discuss normal aspects of cognitive development in older adulthood. Ageing is associated with changes in memory and other cognitive functions throughout the lifespan. In older people, subjective cognitive complaints are common and in the lay population are typically referred to as ‘senior moments’. Specific benign cognitive changes associated with age include declines in processing speed, learning and memory, and executive functioning. Other investigators have demonstrated that declines in visual and auditory acuity contribute to cognitive change as well (Park & Schwarz, 2012). Research has demonstrated that the most pronounced function affected by ageing is processing speed, which reduces with advancing age (Salthouse, 1996; Salthouse, 2010). Importantly, normal cognitive ageing is by definition not associated with objective impairment on cognitive testing and does not result in impairment of individuals’ ability to complete daily activities.

The underlying mechanisms for the cognitive changes associated with the normal ageing process have been considerably researched. Traditionally, it is thought that age‐related cognitive decline is a result of cerebral changes that include loss of volume (e.g. atrophy, particularly affecting the hippocampus and frontal lobes), degradation of myelin, loss of synapses, and cytoskeletal changes (Salthouse, 2010). Not all older adults will experience age‐related cognitive declines. Some continue to have no cognitive symptoms and remain functionally very intact well into older age (Anderton, 2002).