Motor Learning in Sign Language Students

We examined the changes in movement trajectories of two initially naive students from near the beginning until the end of an introductory course in American Sign Language. The movement patterns increased in speed, symmetry, replicability, and grew more constrained in movement amplitude as the semester progressed. Analysis of phase portraits (graphs of displacement versus velocity) revealed increasing limit-cycle behavior for complicated two-handed signs over the testing sessions. One-handed signs, however, exhibited limit-cycle behavior from the first session.