Stimulus Dominance in Dichotic Listening

If, in dichotic listening, vowel onsets of competing plosive-vowel sequences are separated by some 30-60 msec, the signal in the "lagging" ear is more intelligible than in simultaneous presentation (Berlin et al., 1973). The dominance of voiceless over voiced stops in voice-contrasting pairs as found in English (Sepaks and Niccum, 1977) may be due to this lag effect as VOTs of initial voice-contrasting pairs differ radically in English. Therefore, Dutch plosive-vowel sequences, which do not differ much in their VOT values, were presented dichotically. The competing stimuli were aligned with respect to their vocalic boundaries. No dominance of voiceless over voiced plosives could be found for Dutch; on the contrary, there was a slight advantage for voiced over voiceless plosives. When the competing plosives shared the feature voice, a right-ear advantage could be established. Thus, voiceless dominance in English probably results from the noise-burst alignment technique commonly used.