Figure 5.

Stimulus dependency of behavioral interference. A, Interference is asymmetric. P2 training of E₁₀₅ and E₁₆₅ delays P1 training of E₁₃₅, but not vice versa. Learning curves for E₁₀₅ and E₁₆₅ are indistinguishable from learning curves for C₁₃₅. B, Data of the five subjects from the Δ0 h P1–P2 interval on the C₁₃₅ and E₁₀₅ conditions from the original experiment. C, Data for the same five subjects after extra training on new C₁₃₅ and E₁₀₅ conditions in the new, control experiment in which training at the 105° reference orientation could not have suffered from interference. To analyze whether the E₁₀₅ performance was comparable in original (B) and control (C) experiments, a repeated-measures ANOVA [Experiment (original, control) × Condition (C₁₃₅, E₁₀₅) × Session (15)] was carried out. This analysis indicated that the Condition × Experiment interaction was not significant (F_(1,8) = 1.501, p = 0.255). Thus, the performance on the E₁₀₅ condition was similar in both experiments, thereby supporting the conclusion that training at the 105° and 165° reference orientations was not interfered with by training at the 135° reference orientation in the same visual field position.