Cognitive changes: comparative analysis and findings

Cognitive Changes

As people age, there are three main types of cognitive changes that can impair or alter cognitive functioning: mild cognitive impairment (MCI), Alzheimer's, and Parkinson's. All of these syndromes are more severe than the normal decline that is expected with aging, though they do not all reach the severity of dementia. Dementia refers to the "the loss of cognitive functioning- thinking, remembering, and reasoning- and behavior abilities, to such an extent that it interferes with a person's daily life and activities" (NIH, 2013). While there are some similarities between these three conditions, there are also significant differences between the three syndromes. These differences can impact treatment options and also help predict impact on the patient and the family.

MCI is an intermediate stage, which features a more significant cognitive decline than that expected with normal aging, but is not as severe as full-blown dementia. "It can involve problems with memory, language, thinking and judgment that are greater than normal age-related changes" (Mayo Clinic Staff, 2012). In addition to the expected memory problems, some symptoms may include losing one's train of thought, feeling easily overwhelmed, becoming more impulsive, and having difficulty with navigating familiar environments (Mayo Clinic Staff, 2012). In addition, there can be an emotional side to MCI, and those experiencing MCI may be prone to: depression, anxiety, apathy, irritability, and aggression (Mayo Clinic Staff, 2012). While these symptoms can slow functioning, they do not generally interfere with day-to-day activities. However, both the patient and any caregivers and family members should be aware that MCI increases the risk of developing a more severe form of dementia. There are multiple causes for MCI, although it may be caused, at least in part, by the same type of brain changes seen in other forms of dementia. MCI may progress to other diseases linked to dementia, may become stable, and, in some cases, may even revert. In addition to aging, which is the primary risk factor for MCI, those with the APOE-e4 gene are also at higher risk for the disease. In addition, several other lifestyle factors or preexisting conditions can increase one's risk of MCI, including: diabetes, smoking, depression, high blood pressure, high cholesterol, being sedentary, and not engaging in stimulating activities (Mayo Clinic Staff, 2012).

Alzheimer's disease is the most common cause of dementia in older adults. It is a brain disease that is both irreversible and progressive. While Alzheimer's can onset in younger adults, it primarily appears after 60. The root cause of Alzheimer's disease is unknown, though genetics appear to increase susceptibility, particularly the presence of the APOE-e4 gene. Moreover, the damage to the brain appears to begin approximately a decade prior to symptom onset. These changes result in "abnormal deposits of proteins form[ing] amyloid plaques and tau tangles throughout the brain" (NIH, 2013). This impacts the functioning ability of neurons. The damage spreads to the hippocampus, which impacts memories, and, as neurons die, the affected brain regions shrink. MCI is one of the early warnings signs of Alzheimer's. Other cognitive declines, such as problems with "word-finding, vision/spatial issues, and impaired reasoning or judgment" can also be early warning signs of Alzheimer's disease (NIH, 2013). Alzheimer's is a progressive disease, so patients and their families need to prepare for the changes that will occur if the patient lives to the advanced stage of the disease. Moreover, monitoring of the patient is important to assess functioning ability. In mild Alzheimer's diseases, there is increasing memory loss, an impairment of judgment, and some mood or personality changes (NIH, 2013). In moderate Alzheimer's disease, the disease impacts daily functioning, familiar people may become unrecognizable, and the patient may begin to suffer from delusions, hallucinations, and paranoia (NIH, 2013). In severe Alzheimer's disease, the patient can no longer communicate and is completely dependent upon caregivers (NIH, 2013).