Charles Andrew van Hasselt

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BACKGROUND AND OBJECTIVE Cantonese is a tone language. A change in the fundamental frequency pattern within the same phonemic segment causes a change in the lexical meaning. The present study examined the Cantonese tone perception ability of cochlear implant children in comparison with normal-hearing children. It was hypothesized that cochlear implant(More)
Studies have shown that while children acquire all Cantonese tones by age two, they are not able to label them reliably until approximately age 10. One possible explanation for the large age discrepancy may be the different methodologies used. This study aimed to (1) investigate a new research design for the collection of reliable tone perception data from(More)
Most tone perception tests for Cantonese-speaking cochlear implant users have been based on tone identification tasks which require significant cognitive development to be successfully completed. Results from such tests suggest that cochlear implant child users are performing at about chance level and may not be receiving much information about pitch using(More)
OBJECTIVE In tone languages such as Cantonese, a change in tone denotes a change in lexical meaning. The present study investigates the functional benefit of hearing devices in assisting tone perception among children with profound hearing impairment. SUBJECTS Fifty-two children with profound hearing loss were categorized into two groups based on their(More)
Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus-associated disease with high prevalence in Southern Chinese. Using multiparametric flow cytometry, we identified significant expansions of circulating naïve and memory CD4+CD25(high) T cells in 56 NPC patients compared with healthy age- and sex-matched controls. These were regulatory T cells (Treg), as(More)
OBJECTIVES Temporal envelope and periodicity components (TEPC) in the speech signal have potentials to offer important cues for speech recognition especially in tonal languages. The aims of this study are: (i) to investigate the degree of contributions of TEPC to lexical tone identification in Cantonese; and (ii) to investigate whether or not the(More)
This paper describes a study on the effectiveness of expanding the temporal envelope and periodicity component (TEPC) for Cantonese tone perception. The ultimate goal is to develop speech processing techniques that can improve speech perception of hearing prosthesis users. Cantonese is a popular Chinese dialect with a complex lexical tone system. TEPCs are(More)
This study investigated the contributions of temporal periodicity cues and the effectiveness of enhancing these cues for Cantonese tone recognition in noise. A multichannel noise-excited vocoder was used to simulate speech processing in cochlear implants. Ten normal-hearing listeners were tested. Temporal envelope and periodicity cues (TEPCs) below 500 Hz(More)
Tone language speakers use lexical tone or fundamental frequency to signal meaning. Therefore, native tone language alaryngeal speakers encountering difficulty imparting lexical tone variation would suffer loss of speech intelligibility. This study examines the intelligibility of lexical tone produced by four different alaryngeal speech methods, namely:(More)