Twenty young Navy enlisted male volunteers were first rehearsed and then tested before, during, and after whole-body vibration. Fourteen were tested only at 8 Hz, and six were tested at 8 Hz/0.21 g rms, 16 Hz/0.43 g rms and 32 Hz/0.85 g rms, using three paper-and-pencil tasks involving visual, motor, and cognitive skills. The tasks were “Spoke”, a speed of tapping test; “Aiming”, a test of fine motor coordination; and “Coding”, involving mental computation. Results showed an approximately equal decrement effect across conditions in the Spoke and Coding (but not Aiming) tests that conforms with the frequency function embodied in the current international standard (ISO 2631:1978) on human exposure to vibration; but that a modicum of previous vibration experience may be necessary before reliable data are obtained in this kind of testing. Implications for methodology and for the application of the current standard are briefly discussed.
