Muscle Afferents and Parkinson’s Disease
It is clear that Hughlings Jackson was entirely familiar with Parkinson’s disease, although he wrote very little about it. He did, however, give us the essential idea that the tremor and rigidity are released symptoms resulting from the abnormal activity of the lower centres, rather than due to a direct action of the higher centres themselves. Let me quote what he said at a discussion meeting in 1888, when he was much more direct than in his more prepared writings. He stated, “I have submitted the hypothesis, that in paralysis agitans there is wasting of the cells of the middle motor centres ... such a process, a negative one, can cause only the negative symptom paralysis. But being at the same time a loss of control over the anterior horns, there is over activity”, which he saw as resulting from “the taking off of inhibition from the anterior horns” so causing, in his view, first tremor then rigidity (Jackson 1888).
KeywordsNeurol Dystonia Dick
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