Parkinson's disease was first discovered by a British physician named James Parkinson. He published a paper about the disease called "the shaking palsy". Around the early 1960s, researchers found a form of brain damage. This lead to the first treatment for the disease suggesting ways for more effective therapies and have introduce a new medication called "Levodopa"(Shamley 2005). About 50,000
Cognitive deficits are very common in Parkinson's disease particularly for 'executive functions' associated with frontal cortico-striatal networks. Previous work has identified deficits in tasks that require attentional control like task-switching, and reward-based tasks like gambling or reversal learning(Shamley 2005). However, there is a complex relationship between the specific cognitive problems faced by an individual patient, their stage of disease and dopaminergic treatment The task-switch was not separately cued but was based on(Shamley 2005) the implicit reward relevance of spatial and verbal dimensions of successive compound stimuli. Nineteen patients were studied in relative 'on' and 'off' states, induced by dopaminergic medication withdrawal (Hoehn and Yahr stages 1-4). Patients were able to successfully complete the task and establish a bias to one or other dimension in order to gain reward. However the lateral prefrontal cortex and caudate nucleus showed a non-linear(Shamley 2005) U-shape relationship between motor disease severity and regional brain activation. Dopaminergic treatment led to a shift in this U-shape function, supporting the hypothesis of differential neurodegeneration in separate motor and cognitive cortico-striato-thalamo-cortical circuits.
Current Explanation of PD
Parkinson's disease is a progressive neurological disorder that over a million people in the United States have been diagnosed with. This disease is a result of degeneration of nerve cells in a region of the brain that controls movement. Parkinson's disease degenerates dopamine which is a neurotransmitter causing impaired movement. fifty thousand people each year are diagnosed each year and the numbers are expected to rise(Shamley 2005). The symptoms of Parkinson's disease are numerous. The first which is usily the "tip off" is shaking of a limb especially if the body is at rest. Other systems are sleep disturbances, slow movement, not being able to move, personality changes, rigid limbs, speech impairments, sexual difficulties, dementia, and depression. People with this disease usily walk with a shuffling gait, and a stooped posture. The severity of Parkinson's tends to worsen over time(Shamley 2005). There is no definite answer what causes Parkinson's but there are many theories. Parkinson's disease has no confirmed date of when it was first found but researchers have documents of what they think is Parkinson's disease as far back as 3,000 BC(Shamley 2005). There is no cure for Parkinson's disease. Doctors usily proscribe levodopa which increases dopamine levels in the brain. In server cases some patients get brain surgery and implants have been done or used. A surgery which takes dopamine-producing tissue is transplanted into the brain is now being tested. If the surgery works it will prevent the dopamine-producing brain cells from dying. Parkinson's disease is found all over the world and all different ...