ABSOLUTE MEASUREMENT OF THE VIBRATORY THRESHOLD

Abstract

FOR MANY years the appreciation of vibration has been used in the study and diagnosis of various neurologic disorders.¹ Up to the present time both the tuning fork and electrical vibrators² have been used for such determinations. However, while the latter represent a vast improvement over the former, the attendant errors in both have restricted their use to disorders that produce only large changes in the vibratory threshold. Furthermore, such instruments have been incapable of absolute calibration and as a result have been limited to relative studies. Recent investigations on certain neurologic disorders³ and the effect of analgesics and other drugs have again served to emphasize the importance of the vibratory threshold, and it is the purpose of this paper to describe an instrument and a technique that allow the precise measurement of this threshold on an absolute scale. PHYSICAL DESCRIPTION While it is not the purpose