Deficit In Dementia

Discuss the relationship between cholinergic transmission, cognitive deficits in dementia and drugs to enhance cognitive performance.

Dementia can be defined as a syndrome that is caused by a different amount of brain disorders, which gradually progress over many years; activities of daily living are impaired by loss of memory and thinking ability. The symptoms of dementia can be split into three different groups: Cognitive dysfunction (loss of memory, attention and thinking), psychiatric and behavioural problems (depression and personality changes) and difficulty with everyday living (driving etc). (NHS, 2011).

A more progressive form of dementia if known as Alzheimer’s Disease (AD) where development is age-related (the older the…show more content…
There are two main processes that are highly believed to be the main contributor to dementia development, the formation of the amyloid protein and cholinergic transmission (neurotransmitter Acetylcholine (Ach)). The amyloid cascade hypothesis refers to the disposition of the amyloid-β protein in the brain (loss of cholinergic neurons occur in the basal forebrain). Mutations then occur resulting in the gene amyloid precursor protein (APP) developing in the brain, and creating an imbalance between the amyloid- β production and removal; resulting in a cytotoxic build up of the amyloid protein, causing neuritic plaques and neurofibrillary tangles in the brain, which are present in the brain of AD patients (Karran, Mercken and Strooper, 2011). Support for this hypothesis arises from the knowledge that transgenic mice, which express the mutant human gene APP, show the changes most recognizable with AD (plaques and the memory deficits)(Selkoe, 2005).

Cholinergic transmission can be defined as the physiological process that operates the neurotransmitter acetylcholine (ACh) to communicate between cells (Wess, 1993). ACh is used in all movement of the muscles, and the neurotransmission of ACh occurs in the peripheral (PNS) and central nervous systems (CNS). ACh has broadly shown a…show more content…
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