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Stroop dilution refers to the observation that the impact of a color word on the naming of a color bar is reduced if another word-like object is displayed simultaneously. Recently, Brown, Roos-Gilbert, and Carr (1995) concluded that Stroop dilution is due to early-visual interference. This conclusion was evaluated in three experiments. Experiment 1 showed that, contrary to the predictions of an early-visual interference account, (a) diluters that are similar in terms of visual complexity induced different amounts of dilution and (b) the size of the dilution effect is proportional to the size of the Stroop interference effect when the diluters are used as single distractors. Experiments 2 and 3 revealed that when the position of the color bar is pre-cued, Stroop dilution disappears. We argue that these findings support Van der Heijden's (1992) attention-capture account of Stroop dilution.

Perceptual inertia refers to a potential explanation for the observation that during a short period after stimulus onset, the visual system is insensitive to discriminatory detail. The present study attempted to replicate this empirical result in a simple one-item letter-identification task. The results provided little if any support for the construct of perceptual inertia. In the five experiments reported, evidence consistent with perceptual inertia was only obtained in Experiment 5. However, the Experiment 5 results can at least equally parsimoniously be explained in terms of two standard explanatory factors: an effect of precuing of the target position (selective attention) and foreperiod duration (general preparation).

Color-color interference refers to the finding that the naming of a target color is hampered by the simultaneous presentation of an incongruent distractor color somewhere else in the visual field. This interference effect has been attributed to an imperfect input selection (selection-for-processing). We test an alternative account in which it is assumed that (a) target and distractor are identified in parallel without mutual interference, (b) the identified target color has to be selected to control the naming response (selection-for-action), and (c) this selection process takes more time and is less accurate in the incongruent condition than in the control conditions. Experiment 1 shows that color-color interference obtained when a target color, presented at the point of fixation, is flanked by incongruent colors. In Experiments 2 and 3, the central target position is indicated by an additional exogenous selection cue. The results show that an abrupt-onset cue, presented at the central target position 160 ms after the onset of the target and distractors, reduces the interference effect. This finding is interpreted as supporting evidence for a selection-for-action account of color-color interference.