[dry run for talk at LabPhon 11]
This paper explores issues relating to signaling word boundaries from the perspective of Aylett¹s Smooth Signal Redundancy proposal (Aylett 2000, Aylett & Turk 2004, Aylett & Turk 2006). Following Shannon 1948 and Pierce 1961, Aylett proposes that language has evolved to spread redundancy, i.e. recognition likelihood, evenly throughout utterances. This even spreading of information is argued to ensure robust, efficient communication in a potentially noisy environment. In the Smooth Signal Redundancy proposal, the information that enables listeners to identify sequences of elements in an utterance (signal redundancy) comes from two main sources: a) language redundancy, i.e. predictability or recognition likelihood based on lexical, syntactic, semantic and pragmatic factors, and b) acoustic redundancy, i.e. recognition likelihood based on acoustic salience. Smooth signal redundancy is achieved by an inverse, complementary relationship between language redundancy and acoustic redundancy that is implemented via prosodic structure.
While Aylett & Turk (2004) present the case for prosodic prominence as a lever for modulating acoustic salience, the current paper advances the hypothesis that prosodic constituency also fulfils this function. The current paper claims that acoustic redundancy, or relative probability of recognition, of lexical words can be manipulated by signaling their boundaries, and that the occurrence and strength of these boundary markers correlate inversely with language redundancy. Prosodic constituency implements the inverse relationship between language redundancy and word boundary salience. The local, word boundary salience modulations that prosodic constituency governs are implemented within the constraints of global settings of effort and rate.
In this talk, I will show that the Smooth Signal Redundancy hypothesis provides an integrated explanation for a set of seemingly unrelated properties of prosodic constituent structure and its correlates: a hierarchy of boundary strengths, effects of length and symmetry on boundary occurrence, optionality in boundary signaling, and language- and variety- specific correlates of constituency. An additional inverse correlation between language redundancy and acoustic redundancy is hypothesized for sub-syllabic constituents, where the patterning of within-word reduction and strengthening phenomena may be controlled via syllable structure.
References:
Aylett, M.P.(2000).Stochastic suprasegmentals: Relationships between redundancy, prosodic structure and care of articulation in spontaneous speech (http://www.cogsci.ed.ac.uk/~matthewa/thesis_sum.html). PhD thesis, University of Edinburgh.
Aylett, M. & Turk, A. (2004) The smooth signal redundancy hypothesis: A functional explanation for relationships between redundancy, prosodic prominence, and duration in spontaneous speech. Language and Speech, 47(1), 31-56.
Aylett, M. & Turk, A. (2006) Language redundancy predicts syllabic duration and the spectral characteristics of vocalic syllable nuclei. Journal of the Acoustical Society of America 119(5). 3048-3059.
Pierce, J.R.(1961). Symbols,signals and noise:The nature and process of communication.New York: Harper.
Shannon, C. E. (1948). A mathematical theory of communication. Bell System Technical Journal, 27,379423;623656.