Practice does not diminish the role of visual information in on-line control of a precision walking task: Support for the specificity of practice hypothesis

It has been proposed that motor learning is specific to the sources of afferent information available during practice (Proteau, 1992). That hypothesis has obtained support from studies of aiming but not from studies of gross motor skills. The many procedural differences between the two sets of studies might have caused the conflicting results. In the present investigation of a precision walking task, the validity of the specificity of practice hypothesis was tested. Thirty-two participants were asked to walk for 20 m on a 2.5-cm-wide line. Subjects practiced the task for either 20 or 100 trials under normal visual conditions or while blindfolded. Following acquisition, all subjects performed the task for 20 additional trials while blindfolded and without knowledge of results. Practice improved the performance of blindfolded participants. Withdrawing vision in transfer resulted in a large and significant increase in error, however, a finding that supports the specificity of practice hypothesis.