Advanced analysis of finger-tapping performance: a preliminary study

Abstract

Background: The finger-tapping test is a commonly employed quantitative assessment tool used to measure motor performance in the upper extremities. This task is a complex motion that is affected by external stimuli, mood and health status. The complexity of this task is difficult to explain with a single average intertap-interval value (time difference between successive tappings) which only provides general information and neglects the temporal effects of the aforementioned factors.

Aims: This study evaluated the time course of average intertap-interval values and the patterns of variation in both the right and left hands of right-handed subjects using a computer-based finger-tapping system.

Study design: Cross sectional study.

Methods: Thirty eight male individuals aged between 20 and 28 years (Mean±SD = 22.24±1.65) participated in the study. Participants were asked to perform single-finger-tapping test for 10 seconds of test period. Only the results of right-handed (RH) 35 participants were considered in this study. The test records the time of tapping and saves data as the time difference between successive tappings for further analysis. The average number of tappings and the temporal fluctuation patterns of the intertap-intervals were calculated and compared. The variations in the intertap-interval were evaluated with the best curve fit method.

Results: An average tapping speed or tapping rate can reliably be defined for a single-finger tapping test by analysing the graphically presented data of the number of tappings within the test period. However, a different presentation of the same data, namely the intertap-interval values, shows temporal variation as the number of tapping increases. Curve fitting applications indicate that the variation has a biphasic nature.

Conclusion: The measures obtained in this study reflect the complex nature of the finger-tapping task and are suggested to provide reliable information regarding hand performance. Moreover, the equation reflects both the variations in and the general patterns associated with the task.

Keywords: Finger-tapping test; analysis; hand; performance.

Figure 1.

The number of tappings during the test period using right hand single-finger tapping of right-handed (RH) participants. Regression line coefficients and R-squared value of estimated function are given in the inset

Figure 2.

The number of tappings during the test period using left hand single-finger tapping of right-handed (RH) participants. Regression line coefficients and R-squared value of estimated function are given in the inset

Figure 3.

Comparative presentation of three different curve fitting options applied to the same data. Data represent the time course of intertap-interval values of right hand single-finger tapping of right-handed (RH) participants. The coefficients and R-squared values of estimated linear, 2^nd and 4^th order polynomial equations are given in (a), (b) and (c), respectively.

Figure 4.

Comparative presentation of two different curve fitting options applied to the same data. Data represent the time course of intertap-interval values of left hand single-finger tapping of right-handed (RH) participants. R-squared values of both 2^nd (a) and 4^th order (b) polynomial equations are almost identical