Alzheimer’s disease (AD) is the most common neurodegenerative disorder found among older adults at the age of 65 and above (Schwamborn, 2018). Symptoms of AD are memory loss, cognitive declination, disorientation, language deficit, impaired concentration, personal hygiene and self-care declination as well as behaviour and personality changes (Bature, F., Guinn, B. A., Pang, D., & Pappas, Y, 2017).
At this point of time, the exact causes of AD are still not being publicized. However, researchers believe that the early-onset of AD are caused by the genetic mutations related to the production of beta-amyloid protein (Robert V. Kail, 2019). Also, genetic inheritance can be a component that had caused early-onset AD. Although causes of later-onset AD are more complicated and had not been well documented yet, researchers are focusing on studying the relationship of amyloid plagues and neurofibrillary tangles with the AD patient’s brain (Munoz, D. G., & Feldman, H, 2000). According to the beta-amyloid cascade hypothesis (Robert V. Kail, 2019), when beta-amyloid deposits causes neuronal death severely enough, AD is established.
Having no effective treatment for AD patients, there is still ways to alleviate their symptoms. Although drugs provide little long-term relief, cholinesterase inhibitors are an approved drug treatment that can be used to treat AD patients (Briggs, R., Kennelly, S. P., & O'Neill, D, 2016). Behavioural strategies such as putting large calendars to help AD patients with time orientation and memory interventions based on the E-I-E-I-O approach can effectively help AD patients (Robert V. Kail, 2019).
Being the second most common form of progressive neurodegenerative disease, Parkinson’s disease (PD) normally first develops at the age of 60 (DeMaagd, G., & Philip, A. , 2015). Symptoms of PD include tremor, rigidity, slowness of movement, difficulty chewing, swallowing, speaking and impaired coordination (National Institute on Aging (NIA), 2017).
Furthermore, PD is caused by the deterioration of dopamine production in the midbrain (Robert V. Kail, 2019). PD happens when impaired neurons in the brain produces lesser dopamine that is responsible for movements and thus resulted in movement difficulties. Moreover, features of PD include the loss of nerve endings that produce norepinephrine and the presence of Lewy bodies found in brain cells (DeMaagd, G., & Philip, A. , 2015). According to (National Institute on Aging (NIA), 2017), many researchers had now agreed that PD is caused by a combination of genetic factors and environmental factors.
The most common type of therapy given to PD patients is the Levodopa therapy (Jankovic, J., & Aguilar, L. G., 2008). To replenish the declining supply of the patients’ brain, Levodopa is a type of medication that can be used by nerve cells to create dopamine. Moreover, for PD patients that have motor complications and do not respond well with medications, Deep-brain stimulation (DBS) of the subthalamic nucleus (STN) is another option for them (Anna Castrioto, 2014). DBS is a surgical procedure which implants electrodes into the patient’s brain and connects them to the programmable neurostimulator. Neurostimulator and the electrodes painlessly stimulate the brain, helping many of the movement-related symptoms such as trembling and slowness of movement to cease (National Institute on Aging (NIA), 2017)