Associations between sleep, reading, and mathematics in Taiwanese children.

BACKGROUND: Some research shows a link between sleep behaviours and school achievement in English-speaking children and adolescents. AIMS: The current study aimed to examine the relationship between children's sleep behaviours and aspects of their school achievement in Mandarin-speaking children who are living in Taiwan. SAMPLE: The present study reports on 69 second-grade children (age range = 6.84-8.4 years) recruited in Taipei City, Taiwan. METHODS: Children's sleep behaviours were assessed through two standardized parent self-report questionnaires: the Children's Sleep Habits Questionnaire (CSHQ) and the Sleep Disturbance Scale for Children (SDSC). Children undertook three standardized tests of word reading, reading comprehension and math. RESULTS: Key findings include: (i) sleep disturbances are more prevalent when using the CSHQ scale than the SDSC scale, (ii) around half of second graders struggle with general sleep disturbances as observed by the CSHQ scale, (iii) children who go to bed before 22:00 and have at least 9-h sleep tend to exhibit fewer sleep disturbances, (iv) parasomnias as measured by the CSHQ are negatively correlated with reading comprehension after controlling age and nonverbal IQ, and (v) the amount of sleep (naps) during daytime is negatively correlated with Chinese character recognition, reading comprehension and math after controlling age and nonverbal IQ. CONCLUSIONS: There is growing awareness of the value of research that spans culturally and linguistically diverse populations. Our study contributes to ongoing discussions about the relationship between sleep, and skills in reading and math in school-aged children in Taiwan.

Acoustic Features of Oral Reading Prosody and the Relation With Reading Fluency and Reading Comprehension in Taiwanese Children.

PURPOSE: The study aimed to examine whether oral reading prosody-the use of acoustic features (e.g., pitch and duration variations) when reading passages aloud-predicts reading fluency and comprehension abilities. METHOD: We measured vocabulary, syntax, word reading, reading fluency (including rate and accuracy), reading comprehension (in Grades 3 and 4), and oral reading prosody in Taiwanese third-grade children (N = 109). In the oral reading prosody task, children were asked to read aloud a passage designed for third graders and then to answer forced-choice questions. Their oral reading prosody was measured through acoustic analyses including the number of pause intrusions, intersentential pause duration, phrase-final comma pause duration, child-adult pitch match, and sentence-final pitch change. RESULTS: Analyses of variance revealed that children's number of pause intrusions differed as a function of word reading. After controlling for age, vocabulary and syntactic knowledge, and word reading, we found that different dimensions of oral reading prosody contributed to reading rate. In contrast, the number of pause intrusions, phrase-final comma pause duration, and child-adult pitch match predicted reading accuracy and comprehension. CONCLUSIONS: Oral reading prosody plays an important role in children's reading fluency and reading comprehension in tone languages like Mandarin. Specifically, children need to read texts prosodically as evidenced by fewer pause intrusions, shorter phrase-final comma pause duration, and closer child-adult pitch match, which are early predictive makers of reading fluency and comprehension.

Mandarin-speaking preschoolers' pitch discrimination, prosodic and phonological awareness, and their relation to receptive vocabulary and reading abilities.

Cross-linguistic studies have reported that prosodic pattern awareness (e.g., lexical stress and lexical tone) is more important to reading acquisition than phonological awareness. However, few longitudinal studies have been conducted to explore the relations between these variables. This study examined preschoolers' pitch discrimination, prosodic and phonological awareness, and their connection to receptive vocabulary in preschool and reading abilities in first grade. Findings reveal (1) children improve their pitch discrimination and prosodic awareness from preschool to fourth grade; (2) pitch interval discrimination (frequency separation between tones) contributes to receptive vocabulary whereas pitch contour discrimination (patterns of rising and falling pitch) predicts word reading; (3) phonological awareness accounts for more variability in receptive vocabulary than prosodic awareness; whereas the reverse was found for word reading and reading comprehension. Together, prosody and its acoustic cue (i.e., pitch) play a vital role in learning to read Mandarin.

Cross-linguistic contributions of acoustic cues and prosodic awareness to first and second language vocabulary knowledge.

Background: Several studies have revealed that prosody contributes to reading acquisition. However, the relation between awareness of prosodic patterns and different facets of language ability (e.g., vocabulary knowledge) in school-age children remains unclear. This study measured awareness of prosodic patterns using non-speech and speech stimuli. Methods: Hierarchical regression equations were computed to examine links among auditory cues (e.g., amplitude rise time, pitch contour and interval), language-specific prosodic awareness and children's vocabulary knowledge in Mandarin as a first language (L1) and English as a second language (L2) after controlling for age and nonverbal IQ. Results: Results revealed that (1) amplitude envelope rise time discrimination predicted Mandarin L1 and English L2 vocabulary knowledge, (2) Mandarin tone perception and rhyme awareness did not predict Mandarin L1 vocabulary and (3) English rhyme awareness better predicted English L2 vocabulary than did stress production. Conclusion: Our findings suggest that (1) amplitude rise time, which signals syllable boundaries, is a cross-linguistic predictor of vocabulary knowledge and (2) the development of English L2 vocabulary may depend on phonological more than prosodic awareness.

Stress Judgment and Production in English Derivation, and Word Reading in Adult Mandarin-Speaking English Learners.

For monolingual English-speaking children, judgment and production of stress in derived words, including words with phonologically neutral (e.g., -ness) and non-neutral suffixes (e.g., -ity), is important to both academic vocabulary growth and to word reading. For Mandarin-speaking adult English learners (AELs) the challenge of learning the English stress system might be complicated by cross-linguistic differences in prosodic function and features. As Mandarin-speakers become more proficient in English, patterns similar to those seen in monolingual children could emerge in which awareness and use of stress and suffix cues benefit word reading. A correlational design was used to examine the contributions of English stress in derivation with neutral and non-neutral suffixes to English word and nonword reading. Stress judgment in non-neutral derivation predicted word reading after controlling for working memory and English vocabulary; whereas stress production in neutral derivation contributed to word reading and pseudoword decoding, independent of working memory and English vocabulary. Although AELs could use stress and suffix cues for word reading, AELs were different from native English speakers in awareness of non-neutral suffix cues conditioning lexical stress placement. AELs may need to rely on lexical storage of primary stress in derivations with non-neutral suffixes.

Cortical encoding and neurophysiological tracking of intensity and pitch cues signaling English stress patterns in native and nonnative speakers.

We examined cross-language differences in neural encoding and tracking of intensity and pitch cues signaling English stress patterns. Auditory mismatch negativities (MMNs) were recorded in English and Mandarin listeners in response to contrastive English pseudowords whose primary stress occurred either on the first or second syllable (i.e., "nocTICity" vs. "NOCticity"). The contrastive syllable stress elicited two consecutive MMNs in both language groups, but English speakers demonstrated larger responses to stress patterns than Mandarin speakers. Correlations between the amplitude of ERPs and continuous changes in the running intensity and pitch of speech assessed how well each language group's brain activity tracked these salient acoustic features of lexical stress. We found that English speakers' neural responses tracked intensity changes in speech more closely than Mandarin speakers (higher brain-acoustic correlation). Findings demonstrate more robust and precise processing of English stress (intensity) patterns in early auditory cortical responses of native relative to nonnative speakers.

Comparison of emission characteristics between the CdZnO/ZnO quantum wells on ZnO and GaN templates.

CdZnO/ZnO quantum well (QW) samples are grown on GaN and ZnO templates with plasma-assisted molecular beam epitaxy under different conditions of substrate temperature, Cd effusion cell temperature, and O(2) flow rate for emission characteristics comparison. It is found that the Cd incorporation on the ZnO template is generally lower, when compared with that on the GaN template, such that the O(2) flow rate needs to be reduced for stoichiometric CdZnO/ZnO QW growth on the ZnO template. Besides the wurtzite (wt) CdZnO structure, the rock-salt (rs) CdZnO structure exists in the CdZnO well layers when the total Cd content is high. The rs structure may dominate over the wt structure in photoluminescence intensity when the total Cd content is high. In either group of samples on the GaN and ZnO templates, the emission efficiency first increases and then decreases with increasing total Cd content. The low emission efficiency at low (high) Cd content is attributed to the weaker quantum confinement (the poorer crystal quality) of the QWs. The emission efficiencies of the QW samples on the GaN template are generally higher than those on the ZnO template. The carrier localization behavior in a CdZnO/ZnO QW, grown on either GaN or ZnO template, is significantly weaker than that in an InGaN/GaN QW. The strength of the quantum-confined Stark effect generally increases with increasing Cd content in either group of samples on the GaN and ZnO templates.

Effects of overgrown p-layer on the emission characteristics of the InGaN/GaN quantum wells in a high-indium light-emitting diode.

The counteraction between the increased carrier localization effect due to the change of composition nanostructure in the quantum wells (QWs), which is caused by the thermal annealing process, and the enhanced quantum-confined Stark effect in the QWs due to the increased piezoelectric field, which is caused by the increased p-type layer thickness, when the p-type layer is grown at a high temperature on the InGaN/GaN QWs of a high-indium light-emitting diode (LED) is demonstrated. Temperature- and excitation power-dependent photoluminescence (PL) measurements are performed on three groups of sample, including 1) the samples with both effects of thermal annealing and increased p-type thickness, 2) those only with the similar thermal annealing process, and 3) those with increased overgrowth thickness and minimized thermal annealing effect. From the comparisons of emission wavelength, internal quantum efficiency (IQE), spectral shift with increasing PL excitation level, and calibrated activation energy of carrier localization between various samples in the three groups, one can clearly see the individual effects of thermal annealing and increased p-type layer thickness. The counteraction leads to increased IQE and blue-shifted emission spectrum with increasing p-type thickness when the thickness is below a certain value (20-nm p-AlGaN plus 60-nm p-GaN under our growth conditions). Beyond this thickness, the IQE value decreases and the emission spectrum red shifts with increasing p-type thickness.

Psychiatric symptoms in adolescents with Internet addiction: Comparison with substance use.

AIMS: The aim of the present study was to compare psychiatric symptoms between adolescents with and without Internet addiction, as well as between analogs with and without substance use. METHODS: A total of 3662 students (2328 male and 1334 female) were recruited for the study. Self-report scales were utilized to assess psychiatric symptoms, Internet addiction, and substance use. RESULTS: It was found that Internet addiction or substance use in adolescents was associated with more severe psychiatric symptoms. Hostility and depression were associated with Internet addiction and substance use after controlling for other symptoms. CONCLUSIONS: This result partially supports the hypothesis that Internet addiction should be included in the organization of problem behavior theory, and it is suggested that prevention and intervention can best be carried out when grouped with other problem behaviors. Moreover, more attention should be devoted to hostile and depressed adolescents in the design of preventive strategies and the related therapeutic interventions for Internet addiction.