ABSTRACT
Major regions of the brain affected during aging include the hippocampus and the cerebral cortex regions, major sites involved with cognition. The relative severity of aging-associated cognitive changes has been clinically classified into three major categories, that is, primary age-associated memory impairment, mild cognitive impairment (MCI), and dementia. Longitudinal studies reveal that about 15% of individuals with MCI subsequently develop dementia within one year and 50% within three years of follow-up. Evolving research evidence suggests that regular aerobic activities attenuate many of the effects of aging on the brain, thereby reducing risk of MCI and dementia. Research, primarily observational, has identified modifiable medical conditions and lifestyle factors that are associated with attenuation of cognitive decline and reducing risk of the two most common forms of dementia in older individuals, Alzheimer disease (AD) and vascular dementia. AD is responsible for about two-thirds of reported cases of dementia among Americans.
