The influence of a secondary task and type of feedback on adaptation to lateral displacement of the visual array

Summary This experiment was designed to investigate the influence of a secondary attention-demanding force-production task on adaptation to prismatic displacement. Recent suggestions by Finke (1979) lead to the prediction that a secondary task executed during adaptation would interfere with the central component of adaptation (as measured by intermanual transfer), but not the peripheral component (adaptation specific to adapted limb). There were three secondary task conditions (no task, easy task, difficult task). Other factors investigated were: type of feedback (continuous, terminal), hand adapted (right, left) and prism orientation (base right, base left). While negative aftereffect was not influenced by the secondary task manipulation, intermanual transfer results provide partial support for Finke's model. Correlational analyses indicate the importance of task-specific parameters in determining the nature of perceptual-motor adaptation.