Dawn Morales and Harold E. Pashler

Recent work suggests that learning of relatively complex discriminations (e.g., linguistic sounds: Jamison and Morosan, 1986, 1989; Merzenich et al, 1996) can be sped up by fading (i.e., beginning with magnified stimulus differences and gradually reducing the contrast.) We asked whether this would apply to elementary discriminations on a sensory continuum (pitch discrimination, line length discrimination.) We compared fading to hard training, where observers were required to try to distinguish between the same difficult discrimination (the same discrimination as they would be tested upon) for the same number of trials. At least for an elementary continuum, fading does not appear to generally produce superior learning.