BackgroundLearning to read and write using Western musical notation implies the need to link sound with writing. The teaching of traditional musical writing has focused on strategies aimed at "learning to listen" to notes, intervals, chords or rhythms. The assumption underlying these strategies is that these units of notation are in music and making them conscious is an indispensable requirement for later recognizing them in writing or projecting them into a transcript. These assumptions imply the conception of music notation as a transparent instrument, where it is assumed that writing reflects the categories by which we think in music.Many studies have focussed on children´s attempts to notate musical stimuli. Bamberger (1982, 1988 y 1991) and Davidson and Scripp (1988) analyze graphical representations made by children. These studies have suggested developmental trajectories, in which children representations tend to capture an increasing number of melody components like: tones, rhythmic groups, contour, metric relationships. These investigations reinforced the idea of spontaneous use of units and relationships that the musical notation captures.The musicians who develop vocal or instrumental performance skills from reading produce correspondences between the written units and tones, even coming to naturalize those relationships. Studies in children and adults (Burcet 2010, 2013, 2014) showed that it is the acquisition of musical notation that makes it possible to identify the note as a constituent unit of a musical fragment. In this sense, those musicians who develop musical or vocal performance skills while imitation or playing "by ear" do not establish such correspondences. The following question motivate this research: What are the minimum units in which subjects can segment music spontaneously? We present here a preliminary analysis of the interviews made to children without formal musical training in the tasks of writing and describing the constitutive units of a musical fragment.AimTo Know the minimum units that children use when segmenting a musical fragment. MethodWe interviewed 32 children of 8 years old without formal musical training. We select children because, according to Piaget (1961, 1971), they propose creative alternatives to solve problems. Moreover, at the age of 8 they have a knowledge of writing (in language). Finally, we addressed subjects without specific musical knowledge, because musical knowledge could condition the segmentation process in minimal units.As an initial activity, it was requested to listen to a musical fragment, to count the number of sounds that compose the fragment and to represent it with stick marks. The word "sound" was used to avoid the specific connotations that the word "tone" or ?note? implies with music notation. During the interviews, an attempt was made to investigate the segmentation criteria used by the children.ResultsInterviews were transcript and responses were classified according to the following categories: a) without correspondence between graphic elements and sound segments; b) with correspondence between graphical elements and unstable sound segments; c) with correspondence between graphical elements and stable sound segments: i) at the grouping level; (ii) at the grouping level and without internal differentiation; iii) at the grouping level and with differentiation of unstable minimum units and iv) at the grouping level and with a differentiation of stable minimum units.ConclusionsThe note is the minimum unit in the musical notation, but it is not a unit of spontaneous access. Children spontaneously tend to describe minimal units that, in most cases, have a larger or smaller dimension to the note. These units are usually hierarchically organized according to the traits they estimate and the criteria they assume.At the same time, during the development of the interviews it was observed that the estimated units, can contain relative and variable degrees of stability, possibly according to a developmental trajectory that is still to be studied.