Palatnik, A., & Abrahamson, D. (2017). Taking measures to coordinate movements: Unitizing emerges as a method of building event structures for enacting proportion.

In E. Galindo & J. Newton (Eds.), “Synergy at the crossroads” — Proceedings of the 39th annual conference of the North-American chapter of the International Group for the Psychology of Mathematics Education (Ch. 13 [Theory and research methods], pp. 1439-1442). Indianapolis, IN: Hoosier Association of Mathematics Teacher Educators.

Rhythm is a means of production—a scheme for coordinating the enactment of real or imagined physical movements over time, space, material resources, and concerting participants. In activities requiring the coordination of two or more continuous motor actions, rhythmic re-assembly of the actions creates a goal event structure mediating the enactment. Yet building that structure requires first unitizing continuity. Unitizing could thus be conceptualized as a cultural–historical strategy for supporting mundane routines by parsing, distributing, and codifying activity as a sequence of iterated actions of equivalent magnitude. Ipso facto, unitizing shifts us from naive to disciplinary activity: articulated rhythm is an ontogenetic achievement driving cognitive growth. We present empirical data of a student spontaneously measuring continuous actions as her means of organizing the enactment of a bimanual task designed for proportions.

Palatnik.Abrahamson.PMENA-2017.pdf