Corine Astésano

On-line Processing of Pop-Out Words in Spoken French Dialogues

Highlighting relevant information in a discourse context is a major aim of spoken language communication. Prosodic cues such as focal prominences are used to fulfill this aim through the pragmatic function of prosody. To determine whether listeners make on-line use of focal prominences to build coherent representations of the informational structure of the utterances, we used the brain event-related potential (ERP) method. Short dialogues composed of a question and an answer were presented auditorily. The design of the experiment allowed us to examine precisely the time course of the processing of prosodic patterns of sentence-medial or -final words in the answer. These patterns were either congruous or incongruous with regard to the pragmatic context introduced by the question. Furthermore, the ERP effects were compared for words with or without focal prominences. Results showed that pragmatically congruous and incongruous prosodic patterns elicit clear differences in the ERPs, which were largely modulated in latency and polarity by their position within the answer. By showing that prosodic patterns are processed on-line by listeners in order to understand the informational structure of the message, the present results demonstrate the psychobiological validity of the pragmatic concept of focus, expressed via prosodic cues. Moreover, the functional significance of the positive-going effects found sentence medially and negative-going effects found sentence finally is discussed. Whereas the former may reflect the processing of surprising and task-relevant prosodic patterns, the latter may reflect the integration problems encountered in extracting the overall informational structure of the sentence.

Words and Melody Are Intertwined in Perception of Sung Words: EEG and Behavioral Evidence

Language and music, two of the most unique human cognitive abilities, are combined in song, rendering it an ecological model for comparing speech and music cognition. The present study was designed to determine whether words and melodies in song are processed interactively or independently, and to examine the influence of attention on the processing of words and melodies in song. Event-Related brain Potentials (ERPs) and behavioral data were recorded while non-musicians listened to pairs of sung words (prime and target) presented in four experimental conditions: same word, same melody; same word, different melody; different word, same melody; different word, different melody. Participants were asked to attend to either the words or the melody, and to perform a same/different task. In both attentional tasks, different word targets elicited an N400 component, as predicted based on previous results. Most interestingly, different melodies (sung with the same word) elicited an N400 component followed by a late positive component. Finally, ERP and behavioral data converged in showing interactions between the linguistic and melodic dimensions of sung words. The finding that the N400 effect, a well-established marker of semantic processing, was modulated by musical melody in song suggests that variations in musical features affect word processing in sung language. Implications of the interactions between words and melody are discussed in light of evidence for shared neural processing resources between the phonological/semantic aspects of language and the melodic/harmonic aspects of music.

Bridging music and speech rhythm: Rhythmic priming and audio–motor training affect speech perception

Following findings that musical rhythmic priming enhances subsequent speech perception, we investigated whether rhythmic priming for spoken sentences can enhance phonological processing - the building blocks of speech - and whether audio-motor training enhances this effect. Participants heard a metrical prime followed by a sentence (with a matching/mismatching prosodic structure), for which they performed a phoneme detection task. Behavioural (RT) data was collected from two groups: one who received audio-motor training, and one who did not. We hypothesised that 1) phonological processing would be enhanced in matching conditions, and 2) audio-motor training with the musical rhythms would enhance this effect. Indeed, providing a matching rhythmic prime context resulted in faster phoneme detection, thus revealing a cross-domain effect of musical rhythm on phonological processing. In addition, our results indicate that rhythmic audio-motor training enhances this priming effect. These results have important implications for rhythm-based speech therapies, and suggest that metrical rhythm in music and speech may rely on shared temporal processing brain resources.

A novel prosody assessment test: Findings in three cases of Landau–Kleffner syndrome

Landau–Kleffner syndrome (LKS) is a rare childhood neurological disorder characterized by subacute aphasia, auditory agnosia and abnormal EEG. Prosody structures utterances, indicates sentence modality (linguistic prosody) and expresses the speaker’s intention, attitude and emotions (affective prosody). It not only functions as (para-) linguistic features but also provides social explanations. It has been shown that infants can perceive, distinguish and use prosodic features for communication. Since patients with LKS have no more means of verbal communication, we suppose they use some “primitive” cues in an attempt to understand what is said to them. Based on the fact that aphasia does not mean loss of social capacity/functionality, and the precociousness and functions of prosody, the present study investigated prosodic capacity outcomes (possible preservation of prosody) in three individuals - two children and one adolescent - with LKS compared with 7–8 yearold healthy children and healthy adults. A set of perceptual tests of linguistic and affective prosody was elaborated and used for this study. Results revealed that affective prosody is better used in a child with LKS than in the control group under the conditions such as relatively late age at onset, short duration of epilepsy/medication and persistent comprehension problems. Given that prosody appears to be helpful for better oral comprehension, prosody should be used in speech therapy for children with LKS.