Functional load of segments and features

Abstract

The present paper proposes a new measure of functional load for segments and features. In a nut shell, it is based on word frequencies and the number of minimal pairs in which the relevant segment/feature is crucial in distinction. For example, minimal pairs distinguished only by /t/ are most frequent in English while those distinguished by /k/ are most frequent in Japanese. As for functional load of features, single-feature contrasts and multiple-feature contrasts are incorporated in the calculation. In Japanese, [high] alone distinguishes the largest number of minimal pairs while [voice] distinguishes words most frequently in cooperation with other features. Word frequency and familiarity database for English and Japanese are used to observe the commonalities and differences in both languages with respect to the proposed measure of functional load. This line of analysis suggests a better account for a certain phonological process being more typical in one language but not in the other. Functional load can be thought of as a part of the top-down information from the lexicon, which interacts with the bottom-up perceptual information in the process of spoken word recognition. Not only the ease of articulation and perceptual salience but also the functional load drives phonological processes.