Comment on Experiments by Weinstein,et al. on Self-Induced Movement as a Determinant of Spatial Adaptation

Two recent papers by Weinstein, et al. have presented evidence against self-induced movement as a primary determinant of adaptation to prismatic displacement of the visual field. It is shown here that the design of one experiment renders these data invalid as evidence against the role of self-induced movement. It is also suggested that there is need for clarification of the terms “positive” and “negative” adaptation since the direction of these is a function of whether or not S is permitted vision during the pre- and post-exposure tests.