The incongruent color-words paradigm and language lateralization: An EEG-study

The present study utilizes an incongruent color-words paradigm, where color-words are briefly flashed either to the left or to the right of the center of futation. The hypothesis is that a greater conflict between the word and the color the word is written in will occur in the left hemisphere than in the right hemisphere, if the task of the subject is to report only the color. In previous studies, however, only behavioral measures, like vocal reaction time and error frequency, have been used to assess asymmetry. In the presented experiment we have added analysis of the 8–13 Hz EEG alpha difference between the hemispheres, predicting greater alpha reduction to the color-words in the left hemisphere, but not to the control stimuli. Twenty intact, male, dextrals participated. Results supported the prediction, witha 8.3% reduction of alpha activity in the left hemisphere to the color words, compared to a 1.9% reduction in the right hemisphere. No difference was found to the control stimuli.