In Music Therapy, Music is understood as an intentional human action in the happening of musicalities in action. This research sought to understand what improvised and spontaneous sounds reveal in practice. With a qualitative, exploratory methodology, it made use of video recordings and used music therapy analysis (MTA) and microanalysis as data collection tools through descriptive and reflective analysis of the musical event in improvised musical experiences. The triad of listening, reading and music therapy analysis is contemplated, and these constitute the specificities of action for the construction of the music therapy process (MTP). Fragments of moments, one at the beginning and the other at the end, reveal changes in musicality in terms of the duration of musical interaction and the exchange of turns. Through AMT, these changes are understood as cognitive gains, neuronal plasticity and linguistic functions, loaded with traces. Meanings are attributed to these traces, in relation to clinical and life history, in order to better understand MTP