Cues for lexical tone perception in children: acoustic correlates and phonetic context effects

Influence of Lexical Tone Similarity on Spoken Word Recognition in Mandarin Chinese: Evidence From Eye Tracking

PURPOSE

Using the visual world paradigm with the eye-tracking technique, this study examined the extent to which lexical tone similarity influences spoken word recognition.

METHOD

In two experiments, participants were audibly presented with a target word and visually presented with the same target word, a tonal competitor, and two distractors, and they were required to identify the target word. In Experiment 1, the two tonal competitors shared either acoustically highly similar tones (e.g., target word: "" /yang2tai2/, "balcony" vs. competitor: "" /yang3zi3/, "adopted son") or acoustically lowly similar tones (e.g., target word: "" /yang2tai2/, "balcony" vs. competitor: "" /yang4ben3/, "sample"). In Experiment 2, the acoustic similarity of the target words and the tonal competitors shared either acoustically highly similar tones or acoustically lowly similar tones or identical tones (e.g., target word: "" /yang2tai2/, "balcony" vs. competitor: "" /yang2mao2/, "wool").

RESULTS

The results of the two experiments consistently demonstrated a graded tonal competitor effect, in which acoustically highly similar tonal competitors attracted more visual attention than acoustically lowly similar tonal competitors.

CONCLUSION

Tonal similarity plays a graded constraining role in spoken word recognition in Mandarin Chinese.

Speech Prosody and Reading Comprehension in Chinese-English Bilingual Children: The Mediating Role of Syntactic Awareness

PURPOSE

Although children's prosodic sensitivity links with their reading comprehension, the factors affecting this link remain unclear. By simultaneously measuring first language (L1) Chinese and second language (L2) English prosodic sensitivity and reading comprehension, this study examined the mediating role of syntactic awareness on prosody-reading comprehension among Hong Kong Chinese-English bilingual children.

METHOD

A group of 227 Hong Kong Chinese-English bilingual fourth graders completed L1 and L2 prosodic sensitivity (Cantonese lexical tone awareness and English prosodic sensitivity), syntactic awareness, and reading comprehension and control measures of cognitive (nonverbal IQ, short-term memory, and working memory), metalinguistic (phonological awareness and morphological awareness), linguistic (vocabulary knowledge), and word reading skills.

RESULTS

The within-language analyses showed a partial mediation effect of Chinese syntactic awareness on the relation between Cantonese lexical tone awareness and Chinese reading comprehension, but a full mediation effect of English syntactic awareness on the relation between English prosodic sensitivity and English reading comprehension. The cross-language analyses revealed a significant direct effect of Cantonese lexical tone awareness on English reading comprehension and a significant indirect effect of English prosodic sensitivity on Chinese reading comprehension via Chinese syntactic awareness.

CONCLUSION

These findings suggest that, despite the language-independent mediating role of syntactic awareness in bridging prosody and reading comprehension, the degree of this mediation is shaped by language-specific prosody and its relations with other linguistic structures, including semantics.

Distinct Neural Resource Involvements but Similar Hemispheric Lateralization Patterns in Pre-Attentive Processing of Speaker's Identity and Linguistic Information

The speaker's identity (who the speaker is) and linguistic information (what the speaker is saying) are essential to daily communication. However, it is unclear whether and how listeners process the two types of information differently in speech perception. The present study adopted a passive oddball paradigm to compare the identity and linguistic information processing concerning neural resource involvements and hemispheric lateralization patterns. We used two female native Mandarin speakers' real and pseudo-Mandarin words to differentiate the identity from linguistic (phonological and lexical) information. The results showed that, in real words, the phonological-lexical variation elicited larger MMN amplitudes than the identity variation. In contrast, there were no significant MMN amplitude differences between the identity and phonological variation in pseudo words. Regardless of real or pseudo words, the identity and linguistic variation did not elicit MMN amplitudes differences between the left and right hemispheres. Taken together, findings from the present study indicated that the identity information recruited similar neural resources to the phonological information but different neural resources from the lexical information. However, the identity and linguistic information processing did not show a particular hemispheric lateralization pattern at an early pre-attentive speech perception stage. The findings revealed similarities and differences between linguistic and non-linguistic information processing, contributing to a better understanding of speech perception and spoken word recognition.

The Roles of Consonant, Rime, and Tone in Mandarin Spoken Word Recognition: An Eye-Tracking Study

This study investigated the relative role of sub-syllabic components (initial consonant, rime, and tone) in spoken word recognition of Mandarin Chinese using an eye-tracking experiment with a visual world paradigm. Native Mandarin speakers (all born and grew up in Beijing) were presented with four pictures and an auditory stimulus. They were required to click the picture according to the sound stimulus they heard, and their eye movements were tracked during this process. For a target word (e.g., tang2 "candy"), nine conditions of competitors were constructed in terms of the amount of their phonological overlap with the target: consonant competitor (e.g., ti1 "ladder"), rime competitor (e.g., lang4 "wave"), tone competitor (e.g., niu2 "cow"), consonant plus rime competitor (e.g., tang1"soup"), consonant plus tone competitor (e.g., tou2 "head"), rime plus tone competitor (e.g., yang2 "sheep"), cohort competitor (e.g., ta3 "tower"), cohort plus tone competitor (e.g., tao2 "peach"), and baseline competitor (e.g., xue3 "snow"). A growth curve analysis was conducted with the fixation to competitors, targets, and distractors, and the results showed that (1) competitors with consonant or rime overlap can be adequately activated, while tone overlap plays a weaker role since additional tonal information can strengthen the competitive effect only when it was added to a candidate that already bears much phonological similarity with the target. (2) Mandarin words are processed in an incremental way in the time course of word recognition since different partially overlapping competitors could be activated immediately; (3) like the pattern found in English, both cohort and rime competitors were activated to compete for lexical activation, but these two competitors were not temporally distinctive and mainly differed in the size of their competitive effects. Generally, the gradation of activation based on the phonological similarity between target and candidates found in this study was in line with the continuous mapping models and may reflect a strategy of native speakers shaped by the informative characteristics of the interaction among different sub-syllabic components.

The Processing of the Second Syllable in Recognizing Chinese Disyllabic Spoken Words: Evidence From Eye Tracking

In the current study, two experiments were conducted to investigate the processing of the second syllable (which was considered as the rhyme at the word level) during Chinese disyllabic spoken word recognition using a printed-word paradigm. In Experiment 1, participants heard a spoken target word and were simultaneously presented with a visual display of four printed words: a target word, a phonological competitor, and two unrelated distractors. The phonological competitors were manipulated to share either full phonemic overlap of the second syllable with targets (the syllabic overlap condition; e.g., , xiao3zhuan4, "calligraphy" vs. , gong1zhuan4, "revolution") or the initial phonemic overlap of the second syllable (the sub-syllabic overlap condition; e.g., , yuan2zhu4, "cylinder" vs. , gong1zhuan4, "revolution") with targets. Participants were asked to select the target words and their eye movements were simultaneously recorded. The results did not show any phonological competition effect in either the syllabic overlap condition or the sub-syllabic overlap condition. In Experiment 2, to maximize the likelihood of observing the phonological competition effect, a target-absent version of the printed-word paradigm was adopted, in which target words were removed from the visual display. The results of Experiment 2 showed significant phonological competition effects in both conditions, i.e., more fixations were made to the phonological competitors than to the distractors. Moreover, the phonological competition effect was found to be larger in the syllabic overlap condition than in the sub-syllabic overlap condition. These findings shed light on the effect of the second syllable competition at the word level during spoken word recognition and, more importantly, showed that the initial phonemes of the second syllable at the syllabic level are also accessed during Chinese disyllabic spoken word recognition.

The effects of native prosodic system and segmental context on Cantonese tone perception by Mandarin and Japanese listeners

This study explores the effects of native prosodic system and segmental context on the perception of Cantonese tones by Mandarin and Japanese listeners. In Experiment 1, 13 Mandarin and 13 Japanese subjects took part in a two-alternative forced-choice discrimination test of Cantonese tones in different segmental contexts (familiar vs unfamiliar). In Experiment 2, 20 Mandarin listeners participated in a perceptual assimilation task that examined the cross-language perceptual similarity between Mandarin and Cantonese tones. Results showed that Mandarin listeners were comparable to Japanese counterparts in discriminability, but the former attended more to pitch contour differences while the latter were more sensitive to pitch height. Moreover, the effect of segmental context was significant exclusively in the Mandarin group, whereas the Japanese group performed stably across syllables in discriminating Cantonese tones. It seemed that unfamiliar context rendered lower perceptual similarity, which further hindered corresponding discrimination by the Mandarin group. In addition, segmental effects were mainly observed in the assimilation patterns of category goodness or uncategorized-categorized. These findings suggested that non-native tone perception could be modulated by listeners' native prosodic structures in a finer way.

Cantonese advantage on English stress perception: Constraints and neural underpinnings

A prevailing conception of cross-linguistic transfer is that first language experience poses perceptual interference, or at best null effect, on second language speech perception. Surprisingly, a recent study found that Cantonese listeners outperformed English listeners on English stress perception. The present study further evaluated whether segmental variations would constrain the Cantonese advantage on English stress perception. Cantonese and English listeners were tested with both active and passive oddball paradigms in which ERP responses to English stress deviations were elicited. Behaviorally, the Cantonese listeners exhibited a perceptual advantage relative to the English listeners, but this advantage disappeared upon the introduction of segmental variations. Neurophysiologically, segmental variations diminished the P3b amplitudes of the Cantonese but not the English listeners. Collectively, results suggest that segmental variations constrain the Cantonese advantage on English stress perception.

Suprasegmental but not segmental phonological awareness matters in understanding bilingual reading comprehension difficulties in Chinese and English: a 3-year longitudinal study

This study examined whether, and if so how, L1 and L2 segmental and suprasegmental phonological awareness is longitudinally related to L1 and L2 reading comprehension difficulties among Hong Kong Chinese-English bilingual children. Using a regression approach, we identified five types of comprehenders, i.e., 11 poor-Chinese/average-English comprehenders, 19 poor-English/average-Chinese comprehenders, six poor-Chinese/poor-English comprehenders, 12 average-Chinese/average-English comprehenders, and seven good-Chinese/good-English comprehenders among 223 Grade 4 Chinese-English bilingual children who were comparable in age, nonverbal IQ, and word reading, but differed in reading comprehension. These children were compared retrospectively on segmental and suprasegmental phonological awareness in both Chinese and English for three consecutive years from Grade 2 to Grade 4. The results revealed that only Cantonese lexical tone awareness distinguished poor comprehenders from typically developing comprehenders. Specifically, the poor-English/average-Chinese comprehenders performed worse than the average-Chinese/average-English and good-Chinese/good-English comprehenders in Grades 4 and 3, but not in Grade 2; and the poor-Chinese/average-English comprehenders performed worse than the good-Chinese/good-English comprehenders in Grades 4 and 3, but not in Grade 2. These findings suggest that suprasegmental phonological awareness, especially Cantonese lexical tone awareness, is critical for both Chinese and English reading comprehension development among Hong Kong bilingual children.

Statistical Learning of Orthographic Regularities in Chinese Children With and Without Dyslexia

This study examined distributional statistical learning of positional, phonetic, and semantic regularities of an artificial orthography in Chinese children aged 8-10 years: 29 with dyslexia, 29 age-matched controls, and 30 reading-level matched controls. Despite having positional regularity learning performance comparable to the controls, the children with dyslexia were poorer at learning left-right structured characters than top-bottom structured characters in high- and low-consistency conditions. Moreover, they showed difficulties in mapping a given sound or meaning to a specific character compared with the typically developing controls. These findings suggest that children with dyslexia have deficits in some, though not all, aspects of statistical learning of character orthography, which may reflect their difficulties in coping with distractors and inconsistency of orthographic input.

The role of tonal information during spoken-word recognition in Chinese: Evidence from a printed-word eye-tracking study

Two experiments were conducted to investigate the extent to which the lexical tone can affect spoken-word recognition in Chinese using a printed-word paradigm. Participants were presented with a visual display of four words-namely, a target word (e.g., , xiang4xian4, "quadrant"), a tone-consistent phonological competitor (e.g., , xiang4ce4, "photo album"), or a tone-inconsistent phonological competitor (e.g., , xiang1cai4, "coriander"), and two unrelated distractors. Simultaneously, they were asked to listen to a spoken target word presented in isolation (Experiment 1) or embedded in neutral/predictive sentence contexts (Experiment 2), and then click on the target word on the screen. Results showed significant phonological competitor effects (i.e., the fixation proportion on the phonological competitor was higher than that on the distractors) under both tone conditions. Specifically, a larger phonological competitor effect was observed in the tone-consistent condition than in the tone-inconsistent condition when the spoken word was presented in isolation and the neutral sentence contexts. This finding suggests a partial role of lexical tone in constraining spoken-word recognition. However, when embedded in a predictive sentence context, the phonological competitor effect was only observed in the tone-consistent condition and absent in the tone-inconsistent condition. This result indicates that the predictive sentence context can strengthen the role of lexical tone.

From Cantonese Lexical Tone Awareness to Second Language English Vocabulary: Cross-Language Mediation by Segmental Phonological Awareness

Purpose Cantonese lexical tone awareness is closely associated with 1st language Cantonese vocabulary knowledge, but its role in 2nd language English vocabulary knowledge was unclear. We addressed this issue by investigating whether and, if so, how Cantonese lexical tone awareness contributes to English expressive vocabulary knowledge in Hong Kong Cantonese-English bilingual children. Method A sample of 112 Hong Kong Cantonese-English bilingual 2nd graders were tested on Cantonese lexical tone awareness, English lexical stress sensitivity, Cantonese- English segmental phonological awareness, and both Cantonese and English expressive vocabulary knowledge. Results Structural equation modeling analyses revealed that Cantonese lexical tone awareness contributed indirectly to English expressive vocabulary knowledge through English lexical stress sensitivity and Cantonese-English segmental phonological awareness. Conclusion These results demonstrate the role of Cantonese lexical tone awareness in Cantonese-English bilingual children's English vocabulary knowledge. This also underscores the importance of 1st language suprasegmental phonological awareness in 2nd language expressive vocabulary knowledge.

Bidirectional Cross-Linguistic Association of Phonological Skills and Reading Comprehension: Evidence From Hong Kong Chinese-English Bilingual Readers

This study examined the roles of first-language (L1) Chinese and second-language (L2) English phonological skills in English and Chinese reading comprehension, respectively, and their association with reading comprehension difficulties among Hong Kong Chinese-English bilingual children. We tested 258 second graders on nonverbal intelligence, working memory, phonological skills, word reading, and reading comprehension, in both Chinese and English. Structural equation modeling analyses revealed that Chinese phonological skills contributed to English reading comprehension both directly and indirectly, through the mediation of English phonological skills and English word reading. In contrast, English phonological skills contributed only indirectly to Chinese reading comprehension through L1 Chinese phonological and word reading skills. Furthermore, poor Chinese readers, poor English readers, and poor readers in both Chinese and English exhibited lower levels of lexical tone awareness than average readers, even after controlling for nonverbal intelligence, word reading, and working memory. Poor Chinese readers outperformed poor English readers and poor readers in both Chinese and English on Chinese segmental phonological awareness, and their performance was comparable to average readers. These findings suggest that both suprasegmental and segmental phonological skills are critical to the development of reading comprehension across L1 Chinese and L2 English in Hong Kong Chinese-English bilingual children.

Tone matters for Cantonese-English bilingual children's English word reading development: A unified model of phonological transfer

Languages differ considerably in how they use prosodic features, or variations in pitch, duration, and intensity, to distinguish one word from another. Prosodic features include lexical tone in Chinese and lexical stress in English. Recent cross-sectional studies show a surprising result that Mandarin Chinese tone sensitivity is related to Mandarin-English bilingual children's English word reading. This study explores the mechanism underlying this relation by testing two explanations of these effects: the prosodic hypothesis and segmental phonological awareness transfer. We administered multiple measures of Cantonese tone sensitivity, English stress sensitivity, segmental phonological awareness in Cantonese and English, nonverbal ability, and English word reading to 123 Cantonese-English bilingual children ages 7 and 8 years. Structural equation modeling revealed a longitudinal prediction of Cantonese tone sensitivity to English word reading between 8 and 9 years of age. This relation was realized through two parallel routes. In one, Cantonese tone sensitivity predicted English stress sensitivity, and English stress sensitivity, in turn, significantly predicted English word reading, as postulated by the prosodic hypothesis. In the second, Cantonese tone sensitivity predicted English word reading through the transfer of segmental phonological awareness between Cantonese and English, as predicted by segmental phonological transfer. These results support a unified model of phonological transfer, emphasizing the role of tone in English word reading for Cantonese-English bilingual children.

Encoding lexical tones in jTRACE: a simulation of monosyllabic spoken word recognition in Mandarin Chinese

Despite its prevalence as one of the most highly influential models of spoken word recognition, the TRACE model has yet to be extended to consider tonal languages such as Mandarin Chinese. A key reason for this is that the model in its current state does not encode lexical tone. In this report, we present a modified version of the jTRACE model in which we borrowed on its existing architecture to code for Mandarin phonemes and tones. Units are coded in a way that is meant to capture the similarity in timing of access to vowel and tone information that has been observed in previous studies of Mandarin spoken word recognition. We validated the model by first simulating a recent experiment that had used the visual world paradigm to investigate how native Mandarin speakers process monosyllabic Mandarin words (Malins & Joanisse, 2010). We then subsequently simulated two psycholinguistic phenomena: (1) differences in the timing of resolution of tonal contrast pairs, and (2) the interaction between syllable frequency and tonal probability. In all cases, the model gave rise to results comparable to those of published data with human subjects, suggesting that it is a viable working model of spoken word recognition in Mandarin. It is our hope that this tool will be of use to practitioners studying the psycholinguistics of Mandarin Chinese and will help inspire similar models for other tonal languages, such as Cantonese and Thai.

Beyond Auditory Sensory Processing Deficits: Lexical Tone Perception Deficits in Chinese Children With Developmental Dyslexia

Increasing evidence suggests that children with developmental dyslexia exhibit a deficit not only at the segmental level of phonological processing but also, by extension, at the suprasegmental level. However, it remains unclear whether such a suprasegmental phonological processing deficit is due to a difficulty in processing acoustic cues of speech rhythm, such as rise time and intensity. This study set out to investigate to what extent suprasegmental phonological processing (i.e., Cantonese lexical tone perception) and rise time sensitivity could distinguish Chinese children with dyslexia from typically developing children. Sixteen children with dyslexia and 44 age-matched controls were administered a Cantonese lexical tone perception task, psychoacoustic tasks, a nonverbal reasoning ability task, and word reading and dictation tasks. Children with dyslexia performed worse than controls on Cantonese lexical tone perception, rise time, and intensity. Furthermore, Cantonese lexical tone perception appeared to be a stable indicator that distinguishes children with dyslexia from controls, even after controlling for basic auditory processing skills. These findings suggest that suprasegmental phonological processing (i.e., lexical tone perception) is a potential factor that accounts for reading difficulty in Chinese.

Perceptual Improvement of Lexical Tones in Infants: Effects of Tone Language Experience

To learn words in a tonal language, tone-language learners should not only develop better abilities for perceiving consonants and vowels, but also for lexical tones. The divergent trend of enhancing sensitivity to native phonetic contrasts and reduced sensitivity to non-native phonetic contrast is theoretically essential to evaluate effects of listening to an ambient language on speech perception development. The loss of sensitivity in discriminating lexical tones among non-tonal language-learning infants was apparent between 6 and 12 months of age, but only few studies examined trends of differentiating native lexical tones in infancy. The sensitivity in discriminating lexical tones among 6-8 and 10-12 month-old Mandarin-learning infants (n = 120) was tested in Experiment 1 using three lexical tone contrasts of Mandarin. Facilitation of linguistic experience was shown in the tonal contrast (Tone 1 vs. 3), but both age groups performed similar in the other two tonal contrasts (Tone 2 vs. 4; Tone 2 vs. 3). In Experiment 2, 6-8 and 10-12 month-old Mandarin-learning infants (n = 90) were tested with tonal contrasts that have pitch contours either similar to or inverse from lexical tones in Mandarin, and perceptual improvement was shown only in a tonal contrast with familiar pitch contours (i.e., Tone 1 vs. 3). In Experiment 3, 6-8 and 10-12 month-old English-learning infants (n = 40) were tested with Tone 1 vs. 3 contrast of Mandarin and showed an improvement in the perception of non-native lexical tones. This study reveals that tone-language learning infants develop more accurate representations of lexical tones around their first birthday, and the results of both tone and non-tone language-learning infants imply that the rate of development depends on listening experience and the acoustical salience of specific tone contrasts.

From Lexical Tone to Lexical Stress: A Cross-Language Mediation Model for Cantonese Children Learning English as a Second Language

This study investigated how Cantonese lexical tone sensitivity contributed to English lexical stress sensitivity among Cantonese children who learned English as a second language (ESL). Five-hundred-and-sixteen second-to-third grade Cantonese ESL children were tested on their Cantonese lexical tone sensitivity, English lexical stress sensitivity, general auditory sensitivity, and working memory. Structural equation modeling revealed that Cantonese lexical tone sensitivity contributed to English lexical stress sensitivity both directly, and indirectly through the mediation of general auditory sensitivity, in which the direct pathway had a larger relative contribution to English lexical stress sensitivity than the indirect pathway. These results suggest that the tone-stress association might be accounted for by joint phonological and acoustic processes that underlie lexical tone and lexical stress perception.

A Tale of Two Features: Perception of Cantonese Lexical Tone and English Lexical Stress in Cantonese-English Bilinguals

This study investigated the similarities and differences in perception of Cantonese tones and English stress patterns by Cantonese-English bilingual children, adults, and English monolingual adults. All three groups were asked to discriminate pairs of syllables that minimally differed in either Cantonese tone or in English stress. Bilingual children’s performance on tone perception was comparable to their performance on stress perception. By contrast, bilingual adults’ performance on tone perception was lower than their performance on stress perception, and there was a similar pattern in English monolingual adults. Bilingual adults tended to perform better than English monolingual adults on both the tone and stress perception tests. A significant correlation between tone perception and stress perception performance was found in bilingual children but not in bilingual adults. All three groups showed lower accuracy in the high rising-low rising contrast than any of the other 14 Cantonese tone contrasts. The acoustic analyses revealed that average F0, F0 onset, and F0 major slope were the critical acoustic correlates of Cantonese tones, whereas multiple acoustic correlates were salient in English stress, including average F0, spectral balance, duration and intensity. We argue that participants’ difficulty in perceiving high rising-low rising contrasts originated from the contrasts’ similarities in F0 onset and average F0; indeed the difference between their major slopes was the only cue with which to distinguish them. Acoustic-perceptual correlation analyses showed that although the average F0 and F0 onset were associated with tone perception performance in all three groups, F0 major slope was only associated with tone perception in the bilingual adult group. These results support a dynamic interactive account of suprasegmental speech perception by emphasizing the positive prosodic transfer between Cantonese tone and English stress, and the role that level of bilingual language experience and age play in shaping suprasegmental speech perception.

Neural correlates of acoustic cues of English lexical stress in Cantonese-speaking children

The present study investigated the temporal course of neural discriminations of acoustic cues of English lexical stress (i.e., pitch, intensity and duration) in Cantonese-speaking children. We used an event-related potential (ERP) measure with a multiple-deviant oddball paradigm to record auditory mismatch responses to four deviants, namely, a change in pitch, intensity, or duration, or a change in all three acoustic dimensions, of English lexical stress in familiar words. In the time window of 170-270 ms, we found that the pitch deviant elicited significant positive mismatch responses (p-MMRs) and that the duration deviant elicited a mismatch negativity (MMN) response as compared with the standard. In the time window of 270-400 ms, the intensity deviant elicited a significant p-MMR, whereas both the duration and the three-dimension changed deviants elicited significant MMNs. These results suggest that Cantonese-speaking children are sensitive to either single or convergent acoustic cues of English words, and that the relative weighting of pitch, intensity and duration in stress processing may correlate with different ERP components at different time windows in Cantonese second graders.