Attenuated brain responses to speech sounds in moderate preterm infants at term age

Recent findings have revealed that very preterm neonates already show the typical brain responses to place of articulation changes in stop consonants, but data on their sensitivity to other types of phonetic changes remain scarce. Here, we examined the impact of 7–8 weeks of extra‐uterine life on the automatic processing of syllables in 20 healthy moderate preterm infants (mean gestational age at birth 33 weeks) matched in maturational age with 20 full‐term neonates, thus differing in their previous auditory experience. This design allows elucidating the contribution of extra‐uterine auditory experience in the immature brain on the encoding of linguistically relevant speech features. Specifically, we collected brain responses to natural CV syllables differing in three dimensions using a multi‐feature mismatch paradigm, with the syllable/ba/ as the standard and three deviants: a pitch change, a vowel change to/bo/ and a consonant voice‐onset time (VOT) change to/pa/. No significant between‐group differences were found for pitch and consonant VOT deviants. However, moderate preterm infants showed attenuated responses to vowel deviants compared to full terms. These results suggest that moderate preterm infants' limited experience with low‐pass filtered speech prenatally can hinder vowel change detection and that exposure to natural speech after birth does not seem to contribute to improve this capacity. These data are in line with recent evidence suggesting a sequential development of a hierarchical functional architecture of speech processing that is highly sensitive to early auditory experience.     

Irrelevant speech does not interfere with serial recall in early blind listeners

Phonological working memory is known be (a) inversely related to the duration of the items to be learned (word-length effect), and (b) impaired by the presence of irrelevant speech-like sounds (irrelevant-speech effect). As it is discussed controversially whether these memory disruptions are subject to attentional control, both effects were studied in sighted participants and in a sample of early blind individuals who are expected to be superior in selectively attending to auditory stimuli. Results show that, while performance depended on word length in both groups, irrelevant speech interfered with recall only in the sighted group, but not in blind participants. This suggests that blind listeners may be able to effectively prevent irrelevant sound from being encoded in the phonological store, presumably due to superior auditory processing. The occurrence of a word-length effect, however, implies that blind and sighted listeners are utilizing the same phonological rehearsal mechanism in order to maintain information in the phonological store.     

Temporal dynamics of the eye–voice span and eye movement control during oral reading

The distance between eye movements and articulation during oral reading, commonly referred to as the eye–voice span, has been a classic issue of experimental reading research since Buswell (1921). To examine the influence of the span on eye movement control, synchronised recordings of eye position and speech production were obtained during fluent oral reading. The viewing of a word almost always preceded its articulation, and the interval between the onset of a word's fixation and the onset of its articulation was approximately 500 ms. The identification and articulation of a word were closely coupled, and the fixation–speech interval was regulated through immediate adjustments of word viewing duration, unless the interval was relatively long. In this case, the lag between identification and articulation was often reduced through a regression that moved the eyes back in the text. These results indicate that models of eye movement control during oral reading need to include a mechanism that maintains a close linkage between the identification and articulation of words through continuous oculomotor adjustments.     

Performance and interaction anxiety: specific relationships with other- and self-evaluation concerns

This study examines whether performance anxiety (PA) is specifically associated with other-evaluation concerns and interaction anxiety (IA) with self-evaluation concerns. Individuals with public speaking fears and high levels of PA or IA were distinguishable from nonanxious controls on measures taken during a public speaking challenge. In addition, high PA individuals exhibited more observer-rated negative speech characteristics in an Other-Evaluation condition compared to a Self-Evaluation condition, but high IA individuals and nonanxious individuals did not. These results provide some evidence for the distinctiveness of these dimensions of social anxiety.     

听音识人—— 语音频谱与人格特质的关系初探

本研究探索不同情绪状态下说话时单个音素的语音频谱与其人格特质的关系。45个被试参加了16PF人格特质测验, 然后对人格测评的虚假结果进行反馈, 同时报告自己的情绪感受。通过记录被试在不同情绪状态下的回答“是”和“不是”, 然后用语音软件Praat分析辅音/Sh/的频谱参数：前三个共振峰的频率和波段, 结果发现：在平均0.14秒时长的辅音/Sh/上就有了显著的情绪效应, 而且, 频谱参数从中性情绪状态到积极情绪状态的变化量与说话者的情绪稳定性、敢为性存在显著相关; 被试在不同情绪状态下音素/Sh/的频谱参数与部分人格特质有显著相关, 尤其是敢为性、敏感性这类与个体情绪、人际交往行为有密切关系的特质; 此外, 不同情绪状态和回答类型下语音频谱参数与人格特质相关不同。本研究结果预示了从语音频谱揭示说话者人格特质的可能性。     

Interplay between acoustic/phonetic and semantic processes during spoken sentence comprehension: an ERP study

When listening to speech in everyday-life situations, our cognitive system must often cope with signal instabilities such as sudden breaks, mispronunciations, interfering noises or reverberations potentially causing disruptions at the acoustic/phonetic interface and preventing efficient lexical access and semantic integration. The physiological mechanisms allowing listeners to react instantaneously to such fast and unexpected perturbations in order to maintain intelligibility of the delivered message are still partly unknown. The present electroencephalography (EEG) study aimed at investigating the cortical responses to real-time detection of a sudden acoustic/phonetic change occurring in connected speech and how these mechanisms interfere with semantic integration. Participants listened to sentences in which final words could contain signal reversals along the temporal dimension (time-reversed speech) of varying durations and could have either a low- or high-cloze probability within sentence context. Results revealed that early detection of the acoustic/phonetic change elicited a fronto-central negativity shortly after the onset of the manipulation that matched the spatio-temporal features of the Mismatch Negativity (MMN) recorded in the same participants during an oddball paradigm. Time reversal also affected late event-related potentials (ERPs) reflecting semantic expectancies (N400) differently when words were predictable or not from the sentence context. These findings are discussed in the context of brain signatures to transient acoustic/phonetic variations in speech. They contribute to a better understanding of natural speech comprehension as they show that acoustic/phonetic information and semantic knowledge strongly interact under adverse conditions.     

Systematic studies of modified vocalization: speech production changes during a variation of metronomic speech in persons who do and do not stutter

The most common way to induce fluency using rhythm requires persons who stutter to speak one syllable or one word to each beat of a metronome, but stuttering can also be eliminated when the stimulus is of a particular duration (e.g., 1 second [s]). The present study examined stuttering frequency, speech production changes, and speech naturalness during rhythmic speech that alternated 1 s of reading with 1 s of silence. A repeated-measures design was used to compare data obtained during a control reading condition and during rhythmic reading in 10 persons who stutter (PWS) and 10 normally fluent controls. Ratings for speech naturalness were also gathered from naïve listeners. Results showed that mean vowel duration increased significantly, and the percentage of short phonated intervals decreased significantly, for both groups from the control to the experimental condition. Mean phonated interval length increased significantly for the fluent controls. Mean speech naturalness ratings during the experimental condition were approximately “7” on a 1–9 scale (1 = highly natural; 9 = highly unnatural), and these ratings were significantly correlated with vowel duration and phonated intervals for PWS. The findings indicate that PWS may be altering vocal fold vibration duration to obtain fluency during this rhythmic speech style, and that vocal fold vibration duration may have an impact on speech naturalness during rhythmic speech. Future investigations should examine speech production changes and speech naturalness during variations of this rhythmic condition.Educational objectives: The reader will be able to: (1) describe changes (from a control reading condition) in speech production variables when alternating between 1 s of reading and 1 s of silence, (2) describe which rhythmic conditions have been found to sound and feel the most natural, (3) describe methodological issues for studies about alterations in speech production variables during fluency-inducing conditions, and (4) describe which fluency-inducing conditions have been shown to involve a reduction in short phonated intervals.     

Learning foreign sounds in an alien world: videogame training improves non-native speech categorization

Although speech categories are defined by multiple acoustic dimensions, some are perceptually weighted more than others and there are residual effects of native-language weightings in non-native speech perception. Recent research on nonlinguistic sound category learning suggests that the distribution characteristics of experienced sounds influence perceptual cue weights: Increasing variability across a dimension leads listeners to rely upon it less in subsequent category learning (Holt & Lotto, 2006). The present experiment investigated the implications of this among native Japanese learning English /r/-/l/ categories. Training was accomplished using a videogame paradigm that emphasizes associations among sound categories, visual information, and players' responses to videogame characters rather than overt categorization or explicit feedback. Subjects who played the game for 2.5h across 5 days exhibited improvements in /r/-/l/ perception on par with 2-4 weeks of explicit categorization training in previous research and exhibited a shift toward more native-like perceptual cue weights.