Asymmetrical processing of dichotic inputs in undergraduates across sex, handedness, ear-side, and experimental...

Past studies have shown that some female as well as left-handed students do not demonstrate a right-ear advantage (REA) for verbal materials, suggesting that linguistic functions may not be handled in one hemisphere exclusively. To examine these laterality effects more closely, 96 undergraduates were equally divided by sex and hand dominance. Moreover, experimental instructions as to which ear to focus on were provided in a dichotic listening procedure, with left-ear attendance alternating with right-ear across four counterbalanced blocks of 60 trials each. Analysis indicated a major interaction of sex x ear x instructions, with men showing a right-ear advantage when attending to that respective side, highlighting the importance of experimental demands on dichotic performance. The right-ear advantage in right-handed persons was uninfluenced by these instructions, suggesting more pronounced asymmetries in this group.