A specific form of the motet vocal form, developed during medieval times and generally associated with the Ars Nova movement. In the isorhythmic motet, specific rhythmic and pitch patterns are repeated throughout the piece. Initially, these repeated rhythmic and pitch patterns were meant to increase the audibility of the chant line in the tenor voice. However, composers quickly realized that using such isorhythmic patterns in the other voices--which at the time often followed their own unique texts--provided a unifying structure to longer pieces.