The effect of overnight consolidation in the perceptual learning of non-native tonal contrasts

Abstract

Sleep-mediated overnight consolidation has been found to facilitate perceptual learning by promoting learners’ generalization across talkers in their perception of novel segmental categories. Lexical tone is characterized by high variability across talkers, and displays dynamic change over time. For this reason, it remains unclear whether a similar effect of overnight consolidation would be found for perceptual learning of novel tonal contrasts. Thus, this study aims to examine whether overnight consolidation facilitates talker-independent learning of lexical tones in the identification and discrimination of novel Cantonese level tones by Mandarin listeners. Two groups of Mandarin listeners were perceptually trained either in the morning or in the evening. Listeners were trained in a tone identification (ID) task with feedback using stimuli produced by a trained talker. Their post-training changes and generalization to a novel talker were then tested in the ID and AX discrimination tasks using stimuli produced by trained and untrained talkers in three posttests following training: immediately after training, 12-hour delay, and 24-hour delay. While the evening group slept between the first and second posttests, the morning group did not. The accuracy rates in the ID task showed that the evening group showed an improved trend, predicted by their individual sleep time, in identifying the level tones produced by both the trained and untrained talkers; in contrast, the morning group showed a declining trend. The d-prime scores in the AX discrimination task did not show different patterns between the two groups. The finding of sleep-related identification changes over time suggests that overnight consolidation might have facilitated tone learning of stimuli produced by the novel talker and eventually facilitated the formation of a more talker-independent representation of novel tone categories in long-term memory. The results are discussed in light of the features of lexical tones to shed light on the mechanism of phonetic learning.

The Effects of Training Variability and Pitch Aptitude on the Overnight Consolidation of Lexical Tones

“…Overall, the findings of the current study suggest that individual learners had varying degrees of difficulty learning non-native tones (at least, partially) by virtue of the effect of pitch aptitude on tone consolidation (Fuhrmeister & Myers, 2020;Qin & Zhang, 2019). The findings imply that the early emergence of tonal representation is a dynamic process among individual learners, especially when they face training variability (e.g., the inter-talker variability of tones).…”

“…To standardize the data, pitch threshold in semitone was log-transformed and z-normalized prior to the and test (2 levels: ID posttest1 vs. ID posttest2; deviation coding: 0.5, 0.5) were entered as fixed effects, and test was nested within group so that the effect of test is examined within each group. Since the focus of the current study is not the differences among individual level tones (1, 2 and 3), and our previous study (Qin & Zhang, 2019) revealed no effect of tone on overnight consolidation of the level-tonal contrasts, tone is thus not included as a fixed effect in the analysis. Nevertheless, tone was put in the random structure to account for its potential effect on response accuracy.…”

“…While the effects of inter-talker variability during training (henceforth, training variability) have been tested in perceptual learning (Wayland & Guion, 2004;P. Wong & Lam, 2021) and overnight consolidation (Qin, Gong, et al, 2021;Qin & Zhang, 2019; for long-term retention, see Wang et al, 1999) of lexical tones, the findings are mixed in terms of its beneficial impact.…”

“…In addition to ndesirable y caused by the degree of trial-to-trial variability in the talker-mixed design, training variability may interfere with memory consolidation and eventually disrupt long-term retention of learned tones, for instance, among learners with lower aptitude (Fuhrmeister & Myers, 2017Tucker & Fishbein, 2008). In general, sleep-dependent memory consolidation, right after training, was found to enhance consolidation of learned speech information by facilitating the transfer of episodic information from an acoustic-sensory-based trace to a more robust (i.e., contextindependent) representation of speech sounds (Earle & Myers, 2015;Fenn et al, 2013) (Perrachione et al, 2011;Sadakata & McQueen, 2014), and few studies have adopted an overnight design (i.e., over two consecutive days) to segregate post-training performance and post-sleep change (for an example, see Qin & Zhang, 2019).…”

L’hypothèse du déficit procédural : apport pour la compréhension du trouble développemental du langage, sa spécificité et ses comorbidités

“…DÉFICIT PROCÉDURAL ET TROUBLE DÉVELOPPEMENTAL DU LANGAGE 14 Ces dernières années, quelques études ont également mis en évidence l'impact positif des processus de consolidation, notamment ceux en jeu au cours du sommeil, sur les apprentissages langagiers (pour des revues, voir Gómez et al, 2011 ;Schreiner & Rasch, 2017), notamment au niveau des processus d'intégration lexicale (Gaskell & Dumay, 2003) de généralisation de régularités importantes pour l'acquisition du langage (Gómez et al, 2006) ou de la discrimination des sons de la parole (Earle & Myers, 2015 ;Qin & Zhang, 2019).…”