Finger tremor in alcoholic patients.

Charcot (1889) divided tremor into three categories: slow, intermediate, and vibratile. He included alcoholic tremor in the 'vibratile' category, i.e., it was of low amplitude as compared with Parkinsonian or hysterical tremor, and occurred at 8 to 9 c/sec. Friedlander (1956) detected tremor of the tip of the index finger by means of an electromagnetic technique. He compared the records obtained from 25 alcoholic patients with those from a similar number of control subjects. He found that the mean amplitude of tremor in the alcoholic group was significantly greater than that displayed by the controls. In addition, the alcoholic group contained a relatively high proportion of subjects in whom the higher frequency tremor components, i.e., at 8 to 12 c/sec. and above, were particularly prominent. In the records from two subjects who displayed an obvious tremor on physical examination, activity at 6 c/sec. was abnormally accentuated. In view of these reports, the objects of the present investigation were as follows: first, to compare the tremor amplitude observed in a group of alcoholic patients with that occurring in a series of normal control subjects, using aprecise technique ofmeasurement; secondly, to determine, by means of frequency analysis, whether there was any difference in the relative amplitudes of tremor components at different frequencies in alcoholic patients as compared with normal subjects; and thirdly, since it has been shown by Graham (1945) and by Redfearn (1957) that neurotic or anxious patients display a larger tremor amplitude than normal controls, it seemed important to determine the extent to which the psychiatric history as well as the presence or absence of organic illness should be taken into account in interpreting the results of a study on tremor in alcoholic patients.