Table 2. Effect of the memory task difficulty and attention conditions on the ERP amplitude.

Results of the two-way ANOVA on ERP mean amplitude, with memory difficulty (no, low and high) and attention condition as factors, for the three tested timewindows. Statistical values (F, ε and P) of attention and memory difficulty main effects and of attention by memory interaction effect are indicated with the control condition included (attention condition factor with 3 levels: attended, control and ignored) and with the control condition excluded (attention condition factor with 2 levels: attended and ignored). Significant effects are highlighted in grey.

		150-200ms			200-250ms			250-300ms
		F	ε	P	F	ε	P	F	ε	P
Control condition included	attention	13.2	0.996	<0.001	38.6	0.893	<0.001	40.2	0.934	<0.001
	memory difficulty	0.1	0.987	0.865	0.9	0.978	0.387	1.9	1.000	0.165
	attention x memory	1.7	0.984	0.171	2.7	0.855	0.048	1.4	0.933	0.246
Control condition excluded	attention	22.6	1.000	<0.001	49.1	1.000	<0.001	66.8	1.000	<0.001
	memory difficulty	0.5	0.963	0.609	1.7	0.984	0.203	1.5	0.953	0.247
	attention x memory	2.9	0.963	0.072	3.2	0.984	0.050	2.2	0.953	0.128