Viewing-position effects in the Stroop task: Initial fixation position modulates Stroop effects in fully colored words

Abstract

550In the Stroop task (Stroop, 1935), participants are instructed to name the color of the ink in which stimuli are presented. A Stroop experiment classically compares three conditions. In the incongruent condition, the stimulus is a color word that is printed in a different color from the one it designates (e.g., the word BLUE printed in green). In the congruent condition, the word and the ink color correspond. Finally, the control condition consists of neutral words or nonwords and provides a baseline for assessing the accuracy and speed with which participants carry out the basic task of naming the ink color. Comparisons of response times (RTs) in these three conditions typically reveal an interference effect (longer RTs in the incongruent condition than in the control condition) and a facilitation effect (shorter RTs in the congruent condition than in the control condition). Interference in the incongruent condition stems from the differential automaticity of the two processes that conflict on those items: reading the word versus naming the ink color (MacLeod & MacDonald, 2000).The mere existence of the Stroop effect is often cited as empirical evidence for the automaticity of reading, which is thought to occur without the possibility of being controlled. This view is supported by many studies indicating that Stroop effects persist in experimental conditions that should help participants ignore the meaning of the word (see, e.g., Lachter, Ruthruff, Lien, & McCann, 2008; see also Lien, Ruthruff, Kouchi, & Lachter, 2010, for a discussion). Participants thus seem to process printed words in the same way, regardless of whether they are informative for the task at hand. In two recent studies, researchers further documented this phenomenon in a new way that took into account the oculomotor dimension of the task, which has been largely neglected up to now in the vast literature on the Stroop effect. In the first study, Hodgson, Parris, Gregory, and Jarvis (2009) investigated the effect of linguistic stimuli on eye-movement programming, using a modified version of the Stroop task that required a sac cadic response rather than a verbal or buttonpress response. The participants' task was to respond by looking toward one of the four color patches that matched the ''ink" color of a centrally presented word and to ignore the word's meaning. Their results demonstrated that saccadeprogramming processes were affected by the word's meaning even when the word form was irrelevant to task performance. In addition, they observed very short intersaccade intervals between initial errors and subsequent corrective saccades, thus suggesting that saccadic responses were programmed in parallel to two goals defined by both the cue word's meaning and color. The authors concluded that written-word cues could ''capture" saccadic behavior in a manner similar to that found for peripheral visual onsets, in a task for which the semantic content of word stimuli must be ignored to effectively perform the task. In the second study, Smilek, Solman...

So Much to Read, So Little Time

“…The optimal viewing position effect. It is important to note that, with the Stroop effect, the interference created by a mismatch between the word name and the ink color is strongest when people are looking at the center of the word than when they are fixating more peripheral letters (Perret & Ducrot, 2010). This is important because of another robustly demonstrated effect-the optimal viewing position (OVP) effect-in which words that are presented in isolation are recognized more efficiently when people are looking in the center of the word than when they are looking at more external letters (O'Regan, Lévy-Schoen, Pynte, & Brugaillère, 1984).…”

“…The pair of panels at the bottom show the participant's potential responses. letters (Perret & Ducrot, 2010). This is important because of another robustly demonstrated effect-the optimal viewing position (OVP) effect-in which words that are presented in isolation are recognized more efficiently when people are looking in the center of the word than when they are looking at more external letters (O'Regan, Lévy-Schoen, Pynte, & Brugaillère, 1984).…”

Red-letter Reading Days: An eye-tracking perspective on Dr Seuss’ Green Eggs and Ham

“…This study found that adults with ADHD fixated longer and more times on the target than the distractor and that these adults made more transitions between the two than adults without ADHD. Interestingly, both interference and facilitation (Stroop effects) are reduced when the first fixation is controlled and the first fixation is located at the end of the word instead of the optimal viewing position (Perret & Ducrot, 2010).…”