Are initial-consonant lengthening and final-vowel lengthening both universal word segmentation cues?

Speech segments are lengthened at the onsets and offsets of linguistic constituents. Final-syllable vowel lengthening is proposed to be a language-universal cue to word segmentation, but cross-linguistic investigations of the perception of initial consonant lengthening are lacking. We compared the use of word-initial consonant lengthening and word-final vowel lengthening by native speakers of English, Hungarian and Italian, using an artificial language learning task and varying vowel and consonant durations between subjects within each language group. Word-final vowel lengthening was only exploited for segmentation by English speakers; we interpret its non-universality as potentially due, at least in part, to language-specific functional loads on vowel duration, used for indicating lexical stress in Italian and vowel identity in Hungarian. By contrast, all three language groups used word-initial consonant lengthening to locate word boundaries, but did not benefit from lengthening of vowels in word-initial syllables. If domain-initial consonant timing effects are universal, it may be because they promote two related but separable processing requirements for the listener: (a) word segmentation, boosted by lengthening across the boundary; (b) lexical access, boosted by articulatory strengthening and lengthening of word onsets.