1 Generalization of Prism Adaptation 1

Prism exposure produces two kinds of adaptive response. Recalibration is ordinary strategic remapping of spatially coded movement commands to rapidly reduce performance error. Realignment is the extraordinary process of transforming spatial maps to bring the origins of coordinate systems into correspondence. Realignment occurs when spatial discordance signals non-correspondence between spatial maps. In Experiment 1, generalization of recalibration aftereffects from prism exposure to post-exposure depended upon the similarity of target pointing limb postures. Realignment aftereffects generalized to the spatial maps involved in exposure. In Experiment 2, the two kinds of aftereffects were measured for three test positions, one of which was the exposure training position. Recalibration aftereffects generalized non-linearly, while realignment aftereffects generalized linearly, replicating Bedford (1989, 1993a) using a more familiar prism adaptation paradigm. Recalibration and realignment require methods for distinguishing their relative contribution to prism adaptation.