Modulation of speech-in-noise comprehension through transcranial current stimulation with the phase-shifted speech envelope

This work is licensed under a Creative Commons Attribution 4.0 License. For more information, see http://creativecommons.org/licenses/by/4.0/Neural activity tracks the envelope of a speech signal at latencies from 50 ms to 300 ms. Modulating this neural tracking through transcranial alternating current stimulation influences speech comprehension. Two important variables that can affect this modulation are the latency and the phase of the stimulation with respect to the sound. While previous studies have found an influence of both variables on speech comprehension, the interaction between both has not yet been measured. We presented 17 subjects with speech in noise coupled with simultaneous transcranial alternating current stimulation. The currents were based on the envelope of the target speech but shifted by different phases, as well as by two temporal delays of 100 ms and 250 ms. We also employed various control stimulations, and assessed the signal-to-noise ratio at which the subject understood half of the speech. We found that, at both latencies, speech comprehension is modulated by the phase of the current stimulation. However, the form of the modulation differed between the two latencies. Phase and latency of neurostimulation have accordingly distinct influences on speech comprehension. The different effects at the latencies of 100 ms and 250 ms hint at distinct neural processes for speech processing.Peer reviewe

Cross-linguistic perception of pitch of Chinese dyslexic children

This study examined the relationship between perception of basic auditory processing measures, detection of suprasegmental features and bilingual literacy among Hong Kong children with and without reading difficulties. Sixty native Cantonese speakers with the average age of 7; 11 participated in the study. Forty-four children were age-matched controls and 16 of them were diagnosed to have dyslexia. A series of tasks assessing auditory processing ability, detection of suprasegmental features of both Chinese and English and literacy were given all participants. Tone detection was the strongest predictor to all the scores of Chinese literacy task. There was no significant difference in sensitivity to English prosody task between groups. For auditory processing measures, significant differences between groups were only found in 1 rise and intensity task. Regression analysis showed that auditory threshold of rise time discrimination predicted 20% unique variance of sensitivity to tone detection. We concluded that detection of lexical tone in Chinese was an important linguistic marker that may help diagnose children with reading difficulties in Chinese. Normal children made use of intensity cues to detect rise time. Suggestions were also made to improve the validity of English prosody sensitivity task.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

Electrophysiological correlates of the spatial temporal order judgment task

The study investigated auditory temporal processing on a tens of milliseconds scale that is the interval when two consecutive stimuli are processed either together or as distinct events. Distinctiveness is defined by one's ability to make correct order judgments of the presented sounds and is measured via the spatial temporal order judgement task (TOJ). The study aimed to identify electrophysiological indices of the TOJ performance. Tone pairs were presented with inter-stimulus intervals (ISI) varying between 25 and 75 ms while EEG was recorded. A pronounced amplitude change in the P2 interval was found between the event-related potential (ERP) of tone pairs having ISI = 55 and 65 ms, but it was a characteristic only of the group having poor behavioral thresholds. With the two groups combined, the amplitude change between these ERPs in the P2 interval showed a medium-size correlation with the behavioral threshold.Peer reviewe

Uncovering the myth of learning to read Chinese characters: phonetic, semantic, and orthographic strategies used by Chinese as foreign language learners

Oral Session - 6A: Lexical modeling: no. 6A.3Chinese is considered to be one of the most challenging orthographies to be learned by non-native speakers, in particular, the character. Chinese character is the basic reading unit that converges sound, form and meaning. The predominant type of Chinese character is semantic-phonetic compound that is composed of phonetic and semantic radicals, giving the clues of the sound and meaning, respectively. Over the last two decades, psycholinguistic research has made significant progress in specifying the roles of phonetic and semantic radicals in character processing among native Chinese speakers …postprin

(Dis)connections between specific language impairment and dyslexia in Chinese

Poster Session: no. 26P.40Specific language impairment (SLI) and dyslexia describe language-learning impairments that occur in the absence of a sensory, cognitive, or psychosocial impairment. SLI is primarily defined by an impairment in oral language, and dyslexia by a deficit in the reading of written words. SLI and dyslexia co-occur in school-age children learning English, with rates ranging from 17% to 75%. For children learning Chinese, SLI and dyslexia also co-occur. Wong et al. (2010) first reported on the presence of dyslexia in a clinical sample of 6- to 11-year-old school-age children with SLI. The study compared the reading-related cognitive skills of children with SLI and dyslexia (SLI-D) with 2 groups of children …postprin

Cross-linguistic and cross-scriptal differences in auditory and visual attentional shifts : a comparison between native Mandarin and English speakers

Lallier (2010) proposed that our attentional shifting speed could be shaped by our native language. In our current study we tested this hypothesis by comparing the attentional shift of native English and native Mandarin speakers using the stream segregation paradigm. English and Mandarin are known to be of two contrastive language systems. The rhythmic and scriptal differences between Mandarin and English are discussed. Despite the differences, results revealed no significant difference between the two groups. We proposed that language difference might not have a direct effect on non-language tasks. Some ambiguities in verbal and written domains of the two languages were also discussed.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science

Multisensory learning in adaptive interactive systems

The main purpose of my work is to investigate multisensory perceptual learning and sensory integration in the design and development of adaptive user interfaces for educational purposes. To this aim, starting from renewed understanding from neuroscience and cognitive science on multisensory perceptual learning and sensory integration, I developed a theoretical computational model for designing multimodal learning technologies that take into account these results. Main theoretical foundations of my research are multisensory perceptual learning theories and the research on sensory processing and integration, embodied cognition theories, computational models of non-verbal and emotion communication in full-body movement, and human-computer interaction models. Finally, a computational model was applied in two case studies, based on two EU ICT-H2020 Projects, "weDRAW" and "TELMI", on which I worked during the PhD

Neurofilament-lysosomal genetic intersections in the cortical network of stuttering

The neurobiological underpinnings of stuttering, a speech disorder characterized by disrupted speech fluency, remain unclear. While recent developments in the field have afforded researchers the ability to pinpoint several genetic profiles associated with stuttering, how these specific genetic backgrounds impact neuronal circuits and how they generate or facilitate the emergence of stuttered speech remains unknown. In this study, we identified the large-scale cortical network that characterizes stuttering using functional connectivity MRI and graph theory. We performed a spatial similarity analysis that examines whether the topology of the stuttering cortical network intersects with genetic expression levels of previously reported genes for stuttering from the protein-coding transcriptome data of the Allen Human Brain Atlas. We found that GNPTG – a gene involved in the mannose-6-phosphate lysosomal targeting pathways – was significantly co-localized with the stuttering cortical network. An enrichment analysis demonstrated that the genes identified with the stuttering cortical network shared a significantly overrepresented biological functionality of Neurofilament Cytoskeleton Organization (NEFH, NEFL and INA). The relationship between lysosomal pathways, cytoskeleton organization, and stuttering, was investigated by comparing the genetic interactome between GNPTG and the neurofilament genes implicated in the current study. We found that genes of the interactome network, including CDK5, SNCA, and ACTB, act as functional links between lysosomal and neurofilament genes. These findings support the notion that stuttering is due to a lysosomal dysfunction, which has deleterious effects on the neurofilament organization of the speech neuronal circuits. They help to elucidate the intriguing, unsolved link between lysosomal mutations and the presence of stuttering

Cross-linguistic and cross-scriptal differences in auditory and visual attentional shifts : comparison between native Cantonese and English speakers

Lallier and colleagues (2010b) put forward a new hypothesis proposing the role of temporal interval between salient units in ones native language in shaping the speed of attentional shift. The present study investigated the applicability of this hypothesis to Cantonese speakers and English speakers by comparing their speed of attentional shift in auditory and visual stream segregation tasks. Contrary to Lallier et al.’s hypothesis, results of stepwise regressions revealed no group difference in the segregation thresholds in both modalities after controlling the participants’ mean reaction time and alerting score in the Flanker task, suggesting that the speed of attentional shift is language-independent. Additionally, this study established the normative data of attentional shift in the typical Cantonese-speaking adults. This information can serve as a basis for evaluating the relevance of “sluggish attentional shift” (SAS) to developmental dyslexia in Chinese with a logographic script, which may provide clinical insights to its diagnosis.published_or_final_versionSpeech and Hearing SciencesBachelorBachelor of Science in Speech and Hearing Science