The rhythms of rhythm

Abstract

The low frequency (LF) spectral analysis or ‘rhythm spectrum’ approach to the quantitative analysis and comparison of speech rhythms is extended beyond syllable or word rhythms to ‘rhetorical rhythms’ in read-aloud narratives, in a selection of exploratory scenarios, with the aim of developing a unified theory of speech rhythms. Current methodologies in the field are first discussed, then the choice of data is motivated and the modulation-theoretic rhythm spectrum and rhythm spectrogram approach is applied to the amplitude modulation (AM) and frequency modulation (FM) of speech. New concepts of rhythm formant, rhythm spectrogram and rhythm formant trajectory are introduced in the Rhythm Formant Theory (RFT) framework with its associated methodology Rhythm Formant Analysis (RFA) in order to capture second order regularities in the temporal variation of rhythms. The interaction of AM and FM rhythm factors is explored, contrasting English with Mandarin Chinese. The LF rhythm spectrogram is introduced in order to recover temporal information about long-term rhythms, and to investigate the configurative function of rhythm. The trajectory of highest magnitude frequencies through the component spectra of the LF spectrogram is extracted and applied in classifying readings in different languages and individual speaking styles using distance-based hierarchical clustering, and the existence of long-term second order ‘rhythms of rhythm’ in long narratives is shown. In the conclusion, pointers are given to the extension of this exploratory RFT rhythm approach for future quantitative confirmatory investigations.

Rhythm pattern discovery in Niger-Congo story-telling

“…Rhythmic duration differences between neighboring syllables alternate between peaks and valleys, e.g., between positive (long-short) and negative (short-long) differences, but the irregularity measures use absolute or squared values, which turn all differences into positive values and thereby not only lose any relation to peakvalley rhythmic alternation but also introduce an ambiguity, a kind of "overkill": the measures do not distinguish between alternating and non-alternating duration sequences [cf. overviews and discussion in Gibbon (2003Gibbon ( , 2018Gibbon ( , 2021 and Arvaniti (2009)].…”

“…In a full analysis, for example in traditional forms of speech recognition, phones and phone sequences are also demodulated, but detailed phone demodulation is not of immediate interest. FM tones, pitch accents and intonations, i.e., modulations of F0, also contribute to impressions of rhythm, but are not further considered here (Gibbon, 2021).…”

Speech Rhythm as an Elusive Phenomenon in Relation to Its Shape and Function

“…It has to be said that the last two conceptions (quantitative and accentual) are the most widespread in phonetic science. Other definitions which consider verbal rhythm from both aforesaid viewpoints also exist (see Patel et al 2006;Gibbon 2021).…”

Characterizing first and second language rhythm in English using spectral coherence between temporal envelope and mouth opening-closing movements

“…Peak frequencies in the amplitude envelope spectrum have recently been coined as "rhythm formants," emphasizing the low-frequency, high-magnitude spectral zones in sonority fluctuations. 51 A similar method has been used in musical genre analysis, where the spectrum -4 -of the same kind is referred to as the beat histogram. 36 Temporal modulation spectra have been demonstrated to help characterize rhythmic differences within and between languages 37 and in different motor speech disorders.…”

“…[46][47][48] This metrical structure serves as the anchor of intonational phrasing. 49,50 Arguably, speech rhythm can be viewed as a (semi-)regular pulse train with alternating beats differing in prominence degrees (an AM process 51 ), upon which the melody of intonation can develop (an FM process 51 ), in the similar vein as music.…”