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

Effects of speed vs. accuracy in vocal reaction time to visual half-field presentations of incongruent (Stroop) color-words

Incongruent color-words were briefly flashed initially to the left or right hemisphere using the visual half-field (VHF) technique. In half of the trials, subjects were requested to name the word, and in half of the trials they were requested to name the ink the word was written in. Congruent color-words and neutral words served as control-stimuli. Vocal reaction time (VRT) and error-frequency were used as dependent measures. Half of the subjects were instructed to try to be as fast as possible in the task (Speed group), the other half were instructed to try to be as accurate as possible in the task (Accuracy group). All subjects were right handed males. Results showed significantly longer VRTs in the Accuracy group, and more errors in the Speed group to right-field projections (initial left hemisphere input) of the incongruent color-words during the color-naming condition. Thus, the present results have revealed; (a) significant effects of hemispheric asymmetry in an incongruent color-words paradigm; and (b) that the speed vs accuracy dimension interferes with hemisphere differences.