Fluctuation analysis of proficient and dysgraphic handwriting in children

¹  Department of Occupational Therapy, Faculty of Social Welfare & Health Sciences, University of Haifa Mount Carmel, Haifa 31905, Israel
²  Dipartimento di Fisica, Università di Milano-Bicocca - Piazza della Scienza 3, 20126 Milano, Italy, EU

Corresponding author: eduardo.roman@mib.infn.it

Received: 26 November 2008
Accepted: 16 February 2009

Abstract

We analyze handwriting records from several school children with the aim of characterizing the fluctuating behavior of the writing speed. It will be concluded that remarkable differences exist between proficient and dysgraphic handwritings which were unknown so far. It is shown that in the case of proficient handwriting, the variations in handwriting speed are strongly autocorrelated within times corresponding to the completion of a single character or letter, while become uncorrelated at longer times. In the case of dysgraphia, such correlations persist on longer time scales and the autocorrelation function seems to display algebraic time decay, indicating the presence of strong anomalies in the handwriting process. Applications of the results in educational/clinical programs are envisaged.