Insights Into the Effect of General Attentional State, Coarticulation, and Primed Speech Rate in Phoneme Production Time.

Abstract

Purpose: This study aimed to identify how a set of predefined factors modulates phoneme articulation time within a speaker.

Method: We used a custom in-lab system that records lip muscle activity through electromyography signals, aligned with the produced speech, to measure phoneme articulation time. Twenty Spanish-speaking participants (12 females) were evaluated while producing sequences of a consonant-vowel syllable, with each sequence consisting of repeated articulations of either /pa/ or /pu/. Before starting the sequences, participants underwent a priming step with either a fast or slow speech rate. Additionally, the general attentional state level was assessed at the beginning, middle, and end of the protocol. To analyze the variability in the duration of /p/ and vowel articulation, we fitted individual linear mixed-models considering three factors: general attentional state level, priming rate, and coarticulation effects (for /p/, i.e., followed by /a/ or /u/) or phoneme identity (for vowels, i.e., being /a/ or /u/).

Results: We found that the level of general attentional state positively correlated with production time for both the consonant /p/ and the vowels. Additionally, /p/ production was influenced by the nature of the following vowel (i.e., coarticulation effects), while vowel production time was affected by the primed speech rate.

Conclusions: Phoneme duration appears to be influenced by both stable, speaker-specific characteristics (idiosyncratic traits) and internal, state-dependent factors related to the speaker's condition at the time of speech production. While some factors affect both consonants and vowels, others specifically modify only one of these types.

Supplemental material: https://doi.org/10.23641/asha.28608428.