Reduced feedback frequency enhances generalized motor program learning but not parameterization learning.

The purpose of the study was to examine the effects of a reduced feedback frequency on the learning of generalized motor programs and movement parameterization. Subjects practiced three movement patterns with the same relative timing and the same relative amplitude, but with varied movement time (Experiment 1) or varied movement amplitude (Experiment 2). KR was given either on 100% or 63% of the trials, with learning being assessed by retention and transfer tests. In both experiments, reduced KR frequency enhanced GMP learning but generally degraded parameter learning. These data provide converging evidence for the dissociation of the program and parameterization processes postulated in GMP theory.