The effects of semantic content of dichotic inputs and selective attention on the right-ear advantage

The present experiment investigated the effects of attention and semantic content on the Right Ear Advantage (REA) phenomenon in a dichotic listening task. There were three “attention” conditions (right ear, left ear and neutral), which were paired up with each of the four “word-match” conditions resulting in a 3 x 4 mixed factorial design. The research tested Kimura's structural model and Kinsburne's attentional model of dichotic listening. The experiment was focused on three major questions: (a) Is the Right Ear Advantage Effect influenced by attentional factors? (b) Is ipsilateral inhibition influenced by the semantic content of the stimuli? And (c) Does the competition between contralaterally and ipsilaterally presented meaningful words have a detrimental effect on the recall of the contralaterally presented words? The results indicated that the REA effect is significantly influenced by attentional factors capable of even reversing the original REA into a Left Ear Advantage (LEA). Furthermore, the semantic content of the dichotic inputs had no significant effect on ipsilateral inhibition. Finally, competition between dichotically presented meaningful words actually fostered significantly higher recall rates compared to the rest of the “word-match” combinations. Such findings support Kinsburne's attentional model at the contralateral level and Kimura's structural model at the ipsilateral level of dichotic listening.