Han Wu

Speech recognition by second language (L2) learners in optimal and suboptimal conditions has been examined extensively with English as the target language in most previous studies. This study extended existing experimental protocols ( Wang et al., 2013 ) to investigate Mandarin speech recognition by Japanese learners of Mandarin at two different levels (elementary vs. intermediate) of proficiency. The overall results showed that in addition to L2 proficiency, semantic context, F0 contours, and listening condition all affected the recognition performance on the Mandarin sentences. However, the effects of semantic context and F0 contours on L2 speech recognition diverged to some extent. Specifically, there was significant modulation effect of listening condition on semantic context, indicating that L2 learners made use of semantic context less efficiently in the interfering background than in quiet. In contrast, no significant modulation effect of listening condition on F0 contours was found. Furthermore, there was significant interaction between semantic context and F0 contours, indicating that semantic context becomes more important for L2 speech recognition when F0 information is degraded. None of these effects were found to be modulated by L2 proficiency. The discrepancy in the effects of semantic context and F0 contours on L2 speech recognition in the interfering background might be related to differences in processing capacities required by the two types of information in adverse listening conditions.

Despite a strong investor and social demand for firms to disclose information on political connections, mandatory disclosure requirements face considerable opposition. Given the challenges in enforcing mandatory disclosures, we investigate whether private information acquisition can be a viable alternative to disclosure. Using a setting of corruption investigations, we find that investors, on average, are not aware that the firms they have invested in have connections with the officials under investigation, suggesting a lack of visibility of the connections. However, a small number of institutional investors exploit their private access to information and sell their shares in response to the investigations. We also show that the high costs of information acquisition and a lack of incentives for analysts to disseminate sensitive information they have obtained contribute to this lack of visibility and result in a significant delay in retail investors’ reaction to material information. Our study contributes to the debate on mandating disclosure of political connections by showing that the lack of mandatory disclosure results in an uneven playing field that undermines transparency and fairness.

BackgroundDeficits in phonological processing are commonly reported in dyslexia but longitudinal evidence that poor speech perception compromises reading is scant. This 2-year longitudinal ERP study investigates changes in pre-attentive auditory processing that underlies categorical perception of mandarin lexical tones during the years children learn to read fluently. The main purpose of the present study was to explore the development of lexical tone categorical perception to see if it can predict children’s reading ability.MethodsBoth behavioral and electrophysiological measures were taken in this study. Auditory event-related potentials were collected with a passive listening oddball paradigm. Using a stimulus continuum spanning from one lexical tone category exemplar to another, we identified a between-category and a within-category tone deviant that were acoustically equidistant from a standard stimulus. The standard stimulus occurred on 80% of trials, and one of two deviants equiprobably on the remaining trials. 8-year-old Mandarin speakers participated in both an initial ERP oddball paradigm and returned for a 2-year follow-up.ResultsThe between-category MMN and within-category MMN significantly correlate with each other at age 8 but not at age 10. The between-category MMN at age 8 can predict children’s ability at age 10 but the within-category cannot.ConclusionThe categorical perception of lexical tone is still developing from age 8 to age 10. The behavioral and electrophysiological results demonstrate that categorical perception of lexical tone at age 8 predicts children’s reading ability at age 10.