Measuring the error of localization

We describe a procedure to measure the error of localization on the skin. The procedure, which provides for rapid measurement of the error of localization and rapid analysis of the data, uses a digitizing tablet interfaced with a computer. A photocopy of the part of the body to be tested is placed on the digitizing tablet. The subject localizes the stimulus by touching the pen of the digitizing tablet to the photocopy. The location of the pen contact is stored, and the error of localization is determined by the computer. A graphic representation of each subject’s test area can be stored. Both stimulus and response locations can be displayed on this graphic representation. The procedure also allows the same sites on the skin to be tested over a period of weeks or months.