Fig. 6.

Exponential functions applied to group-averaged data for both young and old adults in each condition. The exponential model fit group-averaged data well, as evidenced by the adjusted R-squared values in each panel. When applied to individual participant data, model fits varied from subject to subject, as evidenced by shaded regions in the bottom row of panels in Fig. 3, Fig. 5. All statistical analyses were conducted using data from model fits to individual participant data.