The rhythm of handwriting is present in children from the moment they learn to write

The rhythm of handwriting is present in children from the moment they learn to write

The study, conducted on nearly 300 primary school children, shows that the two principles of the rhythmic organization of handwriting, homothety and isochrony, are already present in children’s first handwriting productions.


This is the main conclusion discovered by an international team of researchers led by the University of Milan-Bicocca with the participation of UPF, Casimiro Mondino Neurological Institute and the University of Southampton. The article is published this July in the journal Scientific Reports.

Although many studies have investigated the geometry and kinematics of handwriting, very little is known about how two principles governing its rhythmic organization, homothety and isochrony, develop over the years. This study, conducted on some 300 primary children, shows that these two principles of the rhythmic organization of handwriting are already present in children’s first handwriting productions.

During the study, the 298 child participants wrote the Italian word “burle” (jokes) ten times: naturally, bigger, smaller, faster and slower, in capital letters and in lower case. The children wrote the word on a digital tablet using an electronic pen. These tools have allowed recording the coordinates of the trace and calculate the geometry and kinematics of movement of the writing.

But what are homothety and isochrony? Homothety states that the ratio between the durations of the motor events composing a writing movement remain unchanged even if the way in which the word is written is different (bigger, smaller, faster or slower).

Taking the example of oral language: if you pronounce the word “ta-vo-lo” spontaneously and then more slowly, the relative duration of the individual syllables does not vary. In the same way, if you write “burle” spontaneously or more slowly, the time taken to write each letter does not vary.

Isochrony, however, refers to the proportional relationship between the speed of movement execution and the length of its trajectory. In other words, when we write we tend to maintain a constant duration. The typical example is the signature. It is always written at the same speed, regardless of its size.

The study shows that children follow these two principles from their first year of primary school. Therefore, early adherence to the principles of homothety and isochrony suggests that an internal representation of the rhythm of writing is already present before the age at which handwriting is performed automatically. Elena Pagliarini, a researcher at UPF’s Center for Brain and Cognition (CBC) and first author of the study states that “even though handwriting is a cultural acquisition, it seems to be conditioned by more general limitations related to the timing of movements”.

The fact that there is no need for a long period of learning in terms of homothety and isochrony has several consequences on studies related to dyslexia and dysgraphia. In a previous study ( conducted by the same authors, it had been shown that children with dyslexia and dysgraphia are not able to satisfy the two principles of the rhythmic organization of handwriting.  This suggests that the difficulties in the use of writing are not related to the fact that they have less time for “training” than other children.

Reference work:

E. Pagliarini, L. Scocchia, M. Vernice, M. Zoppello, U. Balottin, S. Bouamama, M.T. Guasti and N. Stucchi, Children’s first handwriting productions show a rhythmic structure, Scientific Reports; DOI: 10.1038 / s41598-017-05105-6