Observations on Essential Tremor

Essential tremor, which is also known as familial tremor or, when it appears for the first time in old age, as senile tremor, has attracted interest out of proportion to its incidence or importance as a cause of disability. Critchley, surveying the subject in 1949, was able to provide over 100 references to the litera-ture. This interest stems from the unusual features of the condition. It is not, so far as we know, the result of any disease or injury to the nervous system, but appears in otherwise healthy people, persisting throughout their lives, and being unassociated with other signs or symptoms. One important fact is that, though sporadic cases are by no means rare, there is clearly a strong genetic determinant in the con-dition. Apart from this last point, hypotheses have