Finger tremor and cigarette smoking.

1 Finger tremor was recorded with a strain gauge and an accelerometer. 2 Records were subjected to frequency analysis and the amplitude or power at frequencies up to 25 Hz were computed. 3 Comparison was made between the tremor during a control period, during sham smoking and during smoking a cigarette. 4 Smoking significantly increases tremor amplitude by at least twofold over all frequencies from 1 Hz to 25 Hz.