On phrase-final lengthening in Italian Sign Language (LIS), a gradient phenomenon at interface

A very common prosodic phenomenon is phrase-final lengthening, which has been observed not only across languages but also across modalities. This study aims at providing new insights into the nature of phrase-final lengthening in Italian Sign Language (LIS). The data come from the LIS Corpus Project (Geraci et al. 2011), which is the largest LIS corpus currently available. Specifically, the analysis focuses on the nominal expressions produced in spontaneous narratives by 162 LIS Deaf fluent signers. The quantitative analysis suggests that phrase-final lengthening in LIS is a gradient phenomenon, which starts before the last sign of the prosodic constituent and gradually increases towards the right edge. Modulations of the movement component of signs function as kinematic correlates of phrase-final lengthening in a visual language like LIS. Resistance to final lengthening, found in some modifier classes (quantifiers, determiner-like pointing signs, ordinal numerals), might be accounted for by considering some intervening morpho-syntactic factors.