Word length and lexical competition: longer is the same as shorter.

Neighborhood density refers to the number of words that sound similar to a given word. Previous studies have found that neighborhood density influences the recognition of spoken words (Luce & Pisoni, 1998); however, this work has focused almost exclusively on monosyllabic words in English. To investigate the effects of neighborhood density on longer words, bisyllabic words varying in neighborhood density were presented auditorily to participants in a perceptual identification task and a lexical decision task. In the perceptual identification task, words with sparse neighborhoods were more accurately identified than words with dense neighborhoods. In the lexical decision task, words with sparse neighborhoods were responded to more quickly and more accurately than words with dense neighborhoods. These results are similar to those found in studies examining the influence of neighborhood density on the recognition of monosyllabic words in English. In order to better understand lexical processing, models of spoken word recognition must account for the processing of words of all types.