Synonym and antonym pairs in the detection of dichotically and monaurally presented targets: Competing monaural stimulation can generate a substantial right ear advantage

Aligned pairs of spoken words were presented, and the subject timed in detecting the presence or absence of a prespecified target. The target, if present, was paired with either its synonym or its antonym or an unrelated word. If the target was absent, mutually synonymous, antonymous or unrelated word pairs occured. In experiment 1, presentation of the word pairs was dichotic, and in experiment 2 the same stimuli were now systematically presented to a single ear (competing monaural stimulation). In both cases a strategy of divided attention was imposed with respect to the words. A powerful REA was obtained in the second experiment, demonstrating that this phenomenon does not depend upon occlusion of the ipsilateral by the contralateral auditory pathways (Kimura 1961), but that competition within ears is sufficient. Secondly, the nature of the effect (facilitatory or interfering) from a co-present synonym or antonym of the target depends markedly upon how the ears are stimulated, in partial contrast to and extending the results of Lewis (1970).