Age-related Effects on Sensorimotor Control of Speech Production

Abstract

The current study investigates the effect of aging on the speech motor control, more specifically the labial and lingual system. We provide an acoustic and articulatory analysis comparing younger (20-30 years old) and older speakers (70-80 years old) of German, all of them recorded with electromagnetic articulography. We analyzed target words in contrastive focus condition.In the acoustic domain, target syllables were not prolonged in the productions of the older speakers. However, when looking at the articulatory domain, we found systematic modifications: Especially vocalic gestures, requiring movements of the lingual system, showed slower peak velocities for older subjects. Furthermore, we found age-related effects on the symmetry of articulatory gestures. Older subjects produce longer deceleration and shorter acceleration phases leading to a strong asymmetry of the movement components. Variability between and across speakers were considerably higher in the group of older speakers compared to younger ones.Our results on age-related effects on speech motor control are comparable with those from general motor control, where e.g. prolonged deceleration phases are an indicator for a decrease in sensory feedback control.

Incongruencies between phonological theory and phonetic measurement

“…There is also evidence that age affects the precision of speech motor control. In a study on German, Hermes et al (2018) found effects in speech similar to those reported for general motor control. Using 3D electromagnetic articulography, they tracked the movements of the lips and the tongue during the production of consonants and vowels in natural sentences, and found a slowing-down of articulatory movements that was accompanied by a change in the intragestural timing patterns of the primary constrictors during consonant and vowel production, revealing an asymmetry between acceleration and deceleration phases in the way that the deceleration phases were prolonged.…”

“…Based upon the finding reported in Hermes et al (2018), we assume that ageing also affects the timing between gestures, i.e. it leaves a signature in the outcome of syllable-internal coordination patterns.…”

“…We chose stop-lateral patterns since they are described in the literature as being problematic, violating the predictions of articulatory overlap predicted by complex onset organisation (Pouplier 2012, Brunner et al 2014. We compared variation in surface patterns of different German populations that have been described to show changes in the speech motor control system: younger vs. older speakers (Hermes et al 2018) and pathological speech from Essential Tremor patients treated with deep brain stimulation with age-matched healthy control speakers (Mücke et al 2018, Hermes et al 2019. The results will be discussed within Articulatory Phonology, but also with respect to general problems of incongruencies between theoretical predictions and surface patterns.…”

“…3.1.1 Method. The dataset on ageing is based on recordings from Hermes et al (2018). It consists of five older speakers, aged 70-80, and five younger speakers, aged 20-30.…”

Personalizing ASR for Dysarthric and Accented Speech with Limited Data

“…Numerous studies have explored the acoustic, articulatory, and phonetic differences between standard and modified speech. Some of the conditions explored are Parkinsons [18], age [19], dyslexia [20], and ALS [21]. We add to this body of work by describing the phonetic mistakes that a production ASR system makes on a large collection of ALS audio.…”