Hemispheric asymmetry in the processing of Stroop stimuli: an examination of gender, hand-preference, and language...

The present investigation examined the possibility that the explanation for the Stroop phenomenon lies in the hemispheric asymmetry of the human brain. Forty-eight male and 73 female students from freshman psychology classes served as subjects for this study. There were 37 males and 53 females who were right-handed and monolingual; 16 left-handers (five males, 11 females); and 13 bilingual subjects (four male, nine female) included in the sample. Only one person was both left-handed and bilingual. All subjects responded to color words printed in incongruent colors by reading the word or reporting the color in which the word was printed. Response latencies were recorded in hundredths of a second for each of the 36 trials for each subject. For all individuals, response latency was consistently shorter when reading the word than when reporting the color. Females demonstrated a shorter latency for the color stimuli than did males; however males demonstrated a shorter latency for the word stimuli. Evidence indicated that the Stroop phenomenon may best be explained by different modes of neural processing for symbolic and iconic stimuli for all individuals. It was further indicated that females have greater flexibility between hemispheres unless other intervening factors (i.e., hand preference or language differences) provide a symmetry in hemispheric functioning not ordinarily found in males.