Importance of Vowel Harmonic Phase and Fundamental Frequency for Envelope Following Responses
Notice bibliographique
Résumé
OBJECTIVES: The envelope following response (EFR) is a scalp-recorded potential that is phase-locked to envelope periodicities in auditory stimuli such as vowels. Vowel-evoked EFRs are influenced by stimulus characteristics; the most well-studied parameter is the fundamental frequency (f0). Many studies use lower f0 stimuli because they generally elicit larger response amplitudes. Comparatively, the influence of other stimulus characteristics, such as harmonic phase and amplitude spectra, is still poorly understood. The present study emphasizes the investigation of the potential influence of harmonic phase spectra using vowel stimuli. It is hypothesized that the alignment of beating envelopes, which are presumed to be generated by adjacent pairs of vowel harmonics, is a factor contributing to EFR amplitude. DESIGN: Three experiments investigated the effects of varying stimulus parameters on EFRs using vowel tokens derived from 1 male talker with a lower f0 (107.9 Hz) and 1 female talker with a higher f0 (211.6 Hz). A total of 92 adults with normal hearing participated. A single channel was used to record EFRs between the vertex and nape with monaural stimuli. Experiment 1 progressively reduced f0 from the higher f0 to match that of the lower f0 to investigate whether control of f0 alone was sufficient to elicit equivalent amplitude EFRs. Experiment 2 mostly manipulated the phases of stimulus vowel harmonics while matching f0 to study their influence on EFR amplitude. Experiment 3 compared EFR amplitude for vowels with harmonic phases designed with a cochlear model to maximize or minimize EFR amplitude through alignment or opposition of beating envelopes presumed to be generated by adjacent pairs of vowel harmonics. RESULTS: In experiment 1, EFR amplitudes increased as f0 of the female talker was reduced. However, even when f0 was close to the male f0, the EFR amplitude remained lower than that obtained with the male f0. Experiment 2 showed that EFR amplitude changes as harmonic phase spectra are varied while using matched f0 tracks. Furthermore, results suggested that synthesized vowels can elicit EFRs with amplitudes equivalent to a natural utterance by matching f0 and harmonic amplitude and phase spectra. Experiment 3 showed significantly smaller EFR amplitudes for vowels with alternating beating envelopes that encouraged destructive interference. With a lower f0, the alignment of vowel beating envelopes significantly increased EFR amplitude. CONCLUSIONS: The results of experiment 1 support that, in addition to f0, other stimulus factors affect EFR amplitude. Experiment 2 supports that harmonic phase spectra are an important stimulus characteristic for EFR amplitude and that EFRs elicited by natural vowels can be simulated adequately by modeling f0 and harmonic amplitude and phase spectra. Results of experiment 3 support that alignment of stimulus beating envelopes, presumed to be generated in the cochlea between adjacent pairs of harmonics, can lead to larger scalp-recorded EFRs. Designing vowel stimuli with low f0 and harmonic phases optimized to encourage envelope alignment could improve EFR amplitudes and reduce the recording time required to detect them in some individuals.
Récupéré en direct depuis OpenAlex et désinversé. Les résumés ne sont pas conservés dans cette base de données : les index inversés représentent 8,6 Go des 9,3 Go de texte de la base, et le serveur dispose de 13 Go libres.
Comment cette classification a été obtenuedéplier
Prédiction distillée sur la base complète
Imitation des enseignantsNi prévalence calibrée, ni vérité terrain. Validation humaine à venir. Apprise à partir de 10 348 étiquettes directes de Codex et de 10 348 étiquettes directes de Gemma. Le mode candidate est l'union des têtes enseignantes seuillées; le consensus est leur intersection. Ces sorties portent le statut machine_predicted_unvalidated et ne sont ni des étiquettes humaines ni des étiquettes directes de modèles de pointe.
Scores Codex et Gemma par catégorie
| Catégorie | Codex | Gemma |
|---|---|---|
| Métarecherche | 0,000 | 0,000 |
| Méta-épidémiologie (sens strict) | 0,000 | 0,000 |
| Méta-épidémiologie (sens large) | 0,000 | 0,000 |
| Bibliométrie | 0,000 | 0,000 |
| Études des sciences et des technologies | 0,000 | 0,000 |
| Communication savante | 0,000 | 0,000 |
| Science ouverte | 0,000 | 0,000 |
| Intégrité de la recherche | 0,000 | 0,000 |
| Charge utile insuffisante (le modèle a refusé de juger) | 0,000 | 0,000 |
Scores machine (provisoires)
Les deux têtes enseignantes du modèle étudiant, lues sur ce travail. Un score ordonne la base pour la relecture; il n'affirme jamais une catégorie, et le statut de validation accompagne chaque rangée tel quel.
Scores de référence d'un modèle non mature (critères de maturité non atteints, 7 itérations). Un score ordonne; il n'affirme jamais une catégorie.
score_only:v0-immature-baseline · tel quel depuis la passe de notation : score_only signifie que le nombre peut ordonner les travaux, et qu'aucune étiquette de catégorie n'en découleClassification
machine, non validéePrédiction automatique; un appel candidat d’une seule tête enseignante, pas un consensus.
Le détail, modèle par modèle et score par score, se trouve en fin de page sous « Comment cette classification a été obtenue ».