Publications by authors named "Axu Hu"

In modern society, visual symbols such as logos, icons, and letters have become essential for communication and cognition, playing a crucial role in daily life. This study focuses on app icons, a frequently encountered type of symbol, and aims to investigate the neural mechanisms involved in their recognition. Specifically, our objective is to identify the timing and location of brain activity associated with this process.

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The remarkable rapidity and effortlessness of speech perception and word reading by skilled listeners or readers suggest implicit or automatic mechanisms underlying language processing. In speech perception, the implicit mechanisms are reflected by the auditory mismatch negativity (MMN) response, suggesting that phonemic, lexical, semantic, and syntactic information are automatically and rapidly processed in the absence of focused attention. In visual word reading, implicit orthographic and lexical processing are reflected by visual mismatch negativity (vMMN), the visual counterpart of auditory MMN.

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Tonal language speakers outperform non-tonal language speakers in behavioral pitch discrimination. Because the tone system differs in complexity across different tonal languages, it is unknown whether pitch discrimination differs across individuals speaking different tonal languages. There are nine tones in Dong but only four in Mandarin.

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Although mismatch negativity (MMN), a change-specific component of auditory event-related potential, is considered to be an index of sound discrimination accuracy, the amplitude of the MMN responses elicited by pitch height deviations in musicians and tone language speakers with superior pitch discrimination is usually not enhanced compared to that elicited in individuals with inferior pitch discrimination. We hypothesized that superior pitch discrimination is accompanied by enhanced lateral inhibition, a critical neural mechanism that sharpens the tuning curves of the auditory neurons in the tonotopy. Forty Mandarin-speaking healthy adults completed an auditory EEG experiment in which MMN was elicited by pitch height deviations in both pure and harmonic tones.

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The human auditory change detection response known as mismatch negativity (MMN) is an auditory event-related potential that has been extensively used to investigate various aspects of human brain function and dysfunction. However, two competing views of the neural mechanism that underlie MMN have been a subject of debate for decades. The sensory memory hypothesis claims that the MMN reflects sensory memory-based change detection.

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For nontonal language speakers, speech processing is lateralized to the left hemisphere and musical processing is lateralized to the right hemisphere (i.e., function-dependent brain asymmetry).

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