ABSTRACT
Aging is linked to diminished blood flow to the brain, reduced sensory capability, gray and white matter atrophy, reduced neurotransmitter activity, synaptic shrinkage and dendritic regression, as well as less activation of the hippocampal and occipital areas and the loss of overall brain volume. These changes in the brain are largely responsible for age-related decline in intellectual ability. Making sound judgments about complex matters requiring the consideration of many factors takes longer than in middle age. Making the differential diagnosis between the lower range normal intellectual functioning and mild cognitive impairment (MCI) is difficult, and experienced experts can disagree about a diagnosis while looking at the same clinical evidence. The majority of those diagnosed with MCI or mild Alzheimer's disease (AD) will progress toward more severe impairment. The condition shares with AD the gradual unremitting cognitive decline and impaired social and occupational functioning.
