Figure 6.

Data from three studies with Korsakoff patients and controls (Albert et al., 1979; see Studies a–c in our Table 3). In each study, panels 1 and 2 represent easy and hard items, respectively. Open circles represent patient data, solid circles controls. Panels 3 and 4 give the relative retrograde gradient for easy and hard items, respectively, shown with triangles. The solid curves are fits by the model, assuming that a₂ = 0.