[Microcomputer analysis of finger tapping as a measure of cerebellar dysfunction].

As a simple and practical method to measure cerebellar dysfunction, finger tapping was quantitatively analysed with the use of an 8 bit micro-computer. The subject was asked to tap with the index finger on the calibration switch of a conventional EKG apparatus for 30 sec with their best tempo and rhythm. The switch was connected to a micro-computer which measured the tapping interval and calculate their average (I) and standard deviation (SD). The SD was further standardized by a percentage of the average interval ((SD/I)×100 = SD%). These parameters were displayed on a TV-monitor and were recorded on a line-printer and on magnetic tape. This test was applied to three groups of subjects: 111 normal subjects, seven patients of cerebellar hemorrhage, and 18 patients of parkinsonism. In normal subjects, I was 172.9 ± 29.3 msec and SD was 13.3 ± 10.6%. In cerebellar hemorrhage patients, I = 337.4 ± 85.7 msec and SD = 34.6 ± 29.9%, while in parkinsonism patients, I = 414.5 ± 284.7 msec and SD = 12.1 ± 11.4%. The correlation between I and SD was statistically analysed. Differences were significant between all three groups. In summary, this test was simple and effective for the quantitative and chronological analysis of cerebellar function.