First, we examined learning improvements for the signal-in-noise tests. Considering first the signal-noise
motion task (
Fig. 2, top left, visualized in terms of threshold changes, computed as [(thresh
pre – thresh
post)/thresh
pre]), the ANOVA indicated a significant group × time interaction (
F(4, 111) = 6.40,
P < 0.001, η
2p = 0.19). In particular, we observed that signal-noise thresholds improved not only for the group who received dedicated training on the same signal-in-noise motion task (
t(23) = 7.48,
P < 0.001) but also for those who received fine motion training (
t(23) = 3.41,
P = 0.002). Thresholds for this task did not improve for those trained on the orientation cue (signal-in-noise orientation training,
t(23) = 0.87,
P = 0.40; fine orientation training,
t(23) = 0.40,
P = 0.69) or for the control group (
t(19) = 1.55,
P = 0.14). The ANOVA for the signal-noise
orientation test (
Fig. 2, bottom left) indicated a comparable group × time interaction (
F(4, 111) = 3.65,
P = 0.008, η
2p = 0.12). Improvements were limited to participants trained on the two tasks involving the orientation cue (signal-in-noise orientation training,
t(23) = 5.33,
P < 0.001; fine orientation training,
t(23) = 2.87,
P = 0.009). Thresholds for those trained on the motion cue (signal-in-noise motion training,
t(23) = .57,
P = 0.58; fine motion training,
t(23) = 1.62,
P = 0.12) and for the control group (t
(19) = 1.87,
P = 0.08) did not improve.