Perceptual asymmetries and stimulus dominance in dichotic listening with natural fricatives

The present study examined the psychometric properties and the pattern of stimulus dominance in a new task using natural fricatives as consonants in a dichotic consonant-vowel pairs task. The fricatives f, z, s, f, v, and z paired with the vowel a pronounced by a female speaker were presented dichotically to 69 participants (26 males, 43 females) in two sessions of 120 trials. Results revealed a large, reliable, and valid right ear advantage (REA). A pattern of stimulus dominance also emerged, suggesting some dominance on the global level for post-alveolar fricatives over other places of articulation. However, pair by pair examination of the dominance pattern showed a clear tendency for less frequently used fricatives to dominate over more frequently used fricatives. Finally, the significant REA persisted even when syllable pairs where dominance was obtained were considered separately. The findings are discussed in terms of their implications for an understanding of stimulus dominance and future research directions with this novel task. (C) 2011 Elsevier Ltd. All rights reserved.