Discuss the relationship between the cognitive and the biological features of Alzheimer's disease
In order to know the relationship between the cognitive and the biological features of Alzheimer’s disease, it is very important to know the definition of Alzheimer’s disease. Alzheimer is defined as the developed form of dementia that usually begins at the age of 40 years onwards. It usually begins when a person has problems speaking and remembering things and eventually the patients becomes very helpless and dies (Jon et al., 2013). According to its history, in 1906 the first person to talk about this disease was Alois Alzheimer. Following his discovery, the disease was later named after him (Bertram & Tanzi, 2004). The people who are 65 years of age and above are the ones claimed to be getting this disease. There are cases where the disease, which is less prevalent also known as early onset Alzheimer, occurs at an earlier age like 24 years (Walker et al., 2005 p.295).
According to the research that was conducted in 2006, it was observed that around 26.6 million people from all over the world suffer from this disease (Pilotto et al., 2013). The development of the disease occurs in a different way for all the individuals. The symptoms however are universal for all the people. The early forms of symptoms are usually mistaken for being old age problems while other times it may look like a person has stress. According to most researches that have been conducted, it has been found that there is a relationship between the cognitive and the biological features of Alzheimer's disease. This is because biological factors involve the body of a human being especially the brain as well as cognitive features. In order to get the relationship between the two features of Alzheimer’s disease, it is very important to look at the two features and see the relationship it contains. The theory to be used in this essay is the grounded theory. This is because with the grounded theory one can look at other people’s research and come up with a conclusive result of what they want (Charmaz, 2006).
The cognitive and biological feature of Alzheimer’s disease brings about challenges for the elderly and also their caregiver. In both features, the women are the ones at a higher risk of acquiring this disease (Breitner et al., 1988, p.208). In cognitive features of Alzheimer’s disease the result that came up after the research was conducted is that, for the past 20 years, the cognitive impairment that usually comes in the form of Alzheimer disease has become one of the most common challenges especially with the quality of life for the elderly people in the society (Arnáiz, 2003). The progression of cognitive impairment is what brings about the diagnosis of clinical Alzheimer disease (Bäckman et al., 2005, p.525). In the cognitive features when the population is becoming older or ages, the cognitive impairment that brings about the Alzheimer disease probability increases. This is the same as in the biological features of Alzheimer’s disease.
According to the researchers, four genes are associated with the development of both features of Alzheimer’s disease. These genes are amyloid-precursor protein gene, apolipoprotein, Presenilin 1 and presenilin 2 (Boothby et al., 2005). According to the researches that have been conducted, the main reason why the identification of genes was made was that they wanted to understand the molecular biology of the disease (Goldman, 2013). This therefore, shows how important genetics is when it comes to the knowledge of whether an individual will acquire the disease or not. It was also observed that the identical twins have a higher percentage of getting Alzheimer’s disease compared to the fraternal twins. This is due to the combination of both genetics and environmental factors are what brought about the development and progression of the disease. When it comes to the identification of the genetic factors, which cause the risk for an individual to get, this disease is something that has never been proven. One of the genes that have been proven to cause the risk of getting late onset Alzheimer’s is the apolipoprotein.
Apolipoprotein gene is located at the long arm of the 19th chromosome that is commonly associated with the development of the Alzheimer’s disease. The main functions of this gene are for lipid metabolism and transportation (Lovell, P.219). According to the research, conducted it has been confirmed that the increases of the alleles of the apolipoprotein in the body leads to the Alzheimer’s disease (Farrer et al., 1997, p.1350). The Caucasian people are the ones who are at a higher risk of getting this disease because of the presence of allele one.
The amyloid-precursor protein gene is one of the first genes to be associated with the development of the Alzheimer’s disease in the biological feature (Wilket, 2004, p.584). This gene produced a transmembrane protein that contains the beta amyloid, which is well known to be a component of the neuritic plaques that is among the characteristics of the Alzheimer disease development. This is observed when the beta amyloid is at an abnormal rate in which it damages the mitochondria located in the brain thereby causing neuronal dysfunction. This indicates the importance of the mitochondria beta amyloid especially in the development of the biological feature of Alzheimer’s disease (Jankowsky et al., 2004, p.888).
Presenilin 1 gene is a trans-membrane protein that is located in many tissues especially in the brain, which provides it with the neurones. A number of mutations have occurred in the presenilin 1. The mutation of presenilin 1 is what could lead to the early development of the Alzheimer’s disease. This early development of Alzheimer’s disease could start as early as the age of 40 years. There are a few cases where people of ages 24 years have begun having this disease (Conquer et al., 2000, p.1308).
Presenilin 2 is located at the first chromosome and is almost the same as presenilin 1. In presenilin 2, the mutation takes place at a low rate compared to presenilin 1. This will bring about the late onset of Alzheimer’s disease. People who have this mutation are usually overlooked because the symptoms take a longer period for it to be dictated (Walker et al., 2005, p.299).
In cognitive and biological features of Alzheimer’s disease, language disturbance of patients usually begin with the abnormalities with the fluency of how they speak that is commonly characterised with the inability to pronounce ones name for more than a minute or is unable to recall the name of their first born children (Jon et al., 2013). The disturbance in the language after that progresses to aphasia in which the patient gets the lexical selective defects especially when one is asked to name objects or animals and in response, they give phonemic cueing in which they produce correct semantic responses. The disturbance of language continues to another type of aphasia known as transcortical sensory where the patient begins to repeat things. The aphasia will continue to progress and becomes another disorder called the wernicke-type features where the patient will have a reduction in comprehension and also impaired repetition. The disease will continue to palalalia where the patient will have unrecognized output of words or they may have complete mutism (Dickerson et al., 2007, p.1444).
There are those patients with the Alzheimer’s disease who have the disproportionate visuospatial abnormalities. The patients will have problems when it comes to complex constructions, performance IQ measures and block design tasks. The patients will be disoriented because they will be lost indoors, or they will not know which neighbourhood they are in, and that is the place where they might have lived there for years. The patients will also not be able to know familiar places thus they may require assistance from others (Salmon, 2012, p.200).
The posterior-cortical astrophy is also another variant form of both features of Alzheimer’s disease. In this case, the patients will have the features of balint’s syndrome and also the visuospatial disturbances. This will therefore, cause the memories and sight of the patients to be more reserved compared to patients with the classic form of Alzheimer disease who have impaired memories and distorted sights. The patients in this case have reduced metabolic activity especially in the occipital cortical and the parietal (Salmon, 2012, p.188).
A patient with Alzheimer’s disease normally has the hypo-metabolism of the parietal lobe especially early on after diagnosis, and while the disease is progressing. This is the same case for both features of Alzheimer’s disease. When the frontal lobes are involved in the progression of Alzheimer’s disease then the patient will have an impairment of how they verbally speak. They will also have problems when responding to others, and they will have problems paying attention to anything around them. The patients could also have behavioural disturbances that they normally did not have before the diagnosis of the disease (Cummings et al., 2002).
In the cognitive and biological features of Alzheimer’s disease, there are changes in the functions and structures of the blood vessels or the glial cells. These changes could end up impairing the functions of a healthy brain. Astrocytes are an example of glial cells that regulates protect and support the blood vessels and the neurons. One of the major functions of the Astrocytes is to ensure the delivery of new neurons. When one begins to get older the formation of new neurons declines, thus affecting the body functions. Beta-amyloid usually disrupts the functions of the Astrocytes, therefore, causing it not to protect the neurons (Holtzer et al., 2003).
There are usually signs of inflammation in the brains of the patients with both features of Alzheimer’s disease. The inflammation usually functions as a neutralizer against any harmful substance. The continuous inflammation will end up causing damages to the brain tissues. It has been reported that the continuous inflammation will end up causing the neurodegeneration in the Alzheimer’s disease. The APOE gene is the one that causes the risk of one getting the Alzheimer disease because it usually sets off an inflammatory reaction, which breaks down the blood brain barrier. The blood brain barrier functions as a filter that allows the blood vessel cells to enter into the brain (Pilotto et al., 2013).
In conclusion, there is a relationship between the cognitive and the biological features of Alzheimer’s disease. This is because both features appear in the body of a human being most especially the brain. The grounded theory is used in order to get the information needed so as to see the relationship between the two features of Alzheimer’s disease. According to researches, done the development of Alzheimer’s disease is caused by various factors such as genetics, environment and functions of the brains (DeKosky et al., 2004, p.460). The Alzheimer’s disease usually affects a healthy brain thus could end up distorting the memories of a person, speech, repetition of words and forgetting their environment. In both features of Alzheimer’s disease, the patient will have behavioural disturbances and memory loss. The patient will not be able to pronounce their names or remember their neighbourhood.
The cognitive feature in Alzheimer diseases is usually linked with the brain and its functions just the same way as the biological features of Alzheimer’s disease. The genetic factor is one of the common links between the two features of Alzheimer’s disease. This is because there are four types’ genes that are associated with the development of the disease and they are amyloid-precursor protein gene, apolipoprotein, Presenilin 1 and presenilin 2. The apolipoprotein is one of the genes that have been proven to be associated with the progression of this disease in both features. In both features of Alzheimer’s disease, there is inflammation of the brain due to becoming old. The inflammation is used to neutralise the harmful substances. The gene used to cause the inflammation is the apolipoprotein, which is known to cause the progression of Alzheimer’s disease.
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