Xuchu Weng |
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Hangzhou Normal University
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Center for Cognition and Brain Disorders
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Publications (61) View all
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Article: The orthographic sensitivity to written Chinese in the occipital-temporal cortex.
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ABSTRACT: Previous studies have identified an area in the left lateral fusiform cortex that is highly responsive to written words and has been named the visual word form area (VWFA). However, there is disagreement on the specific functional role of this area in word recognition. Chinese characters, which are dramatically different from Roman alphabets in the visual form and in the form to phonological mapping, provide a unique opportunity to investigate the properties of the VWFA. Specifically, to clarify the orthographic sensitivity in the mid-fusiform cortex, we compared fMRI response amplitudes (Exp. 1) as well as the spatial patterns of response across multiple voxels (Exp. 2) between Chinese characters and stimuli derived from Chinese characters with different orthographic properties. The fMRI response amplitude results suggest the existence of orthographic sensitivity in the VWFA. The results from multi-voxel pattern analysis indicate that spatial distribution of the responses across voxels in the occipitotemporal cortex contained discriminative information between the different types of character-related stimuli. These results together suggest that the orthographic rules are likely represented in a distributed neural network with the VWFA containing the most specific information regarding a stimulus' orthographic regularity.Experimental Brain Research 04/2013; · 2.39 Impact Factor -
Article: Neural competition as a developmental process: Early hemispheric specialization for word processing delays specialization for face processing.
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ABSTRACT: Little is known about the impact of learning to read on early neural development for word processing and its collateral effects on neural development in non-word domains. Here, we examined the effect of early exposure to reading on neural responses to both word and face processing in preschool children with the use of the Event Related Potential (ERP) methodology. We specifically linked children's reading experience (indexed by their sight vocabulary) to two major neural markers: the amplitude differences between the left and right N170 on the bilateral posterior scalp sites and the hemispheric spectrum power differences in the γ band on the same scalp sites. The results showed that the left-lateralization of both the word N170 and the spectrum power in the γ band were significantly positively related to vocabulary. In contrast, vocabulary and the word left-lateralization both had a strong negative direct effect on the face right-lateralization. Also, vocabulary negatively correlated with the right-lateralized face spectrum power in the γ band even after the effects of age and the word spectrum power were partialled out. The present study provides direct evidence regarding the role of reading experience in the neural specialization of word and face processing above and beyond the effect of maturation. The present findings taken together suggest that the neural development of visual word processing competes with that of face processing before the process of neural specialization has been consolidated.Neuropsychologia 02/2013; · 3.64 Impact Factor -
Article: Left hemiparalexia of Chinese characters: neglect dyslexia or disruption of pathway of visual word form processing?
Wenchao Yi, Ting Wu, Wei Chen, Ti-Fei Yuan, Benyan Luo, Chunlei Shan, Jianan Li, Sheng He, Xuchu Weng[show abstract] [hide abstract]
ABSTRACT: The objective of the study was to further elucidate the potential mechanisms underlying left hemiparalexia induced by a splenium lesion in corpus callosum. A patient KY, who had infarctions in the splenium and the left ventral medial occipitotemporal area, was examined with neuropsychological tests and fMRI. KY presented left hemiparalexia when he read aloud characters presented in central foveal field tachistoscopically as well as in free-view field. KY also showed left hemialexia for characters in left visual field, while no left hemiparalexia occurred when characters were presented in the right visual field. KY performed poorly in lexical decision tasks. He could judge the directions of Landolt's rings gaps in the left or right visual field equally. The result of fMRI indicated that characters in the left visual field could not activate the visual word form area (VWFA), such as left mid-fusiform cortex. All the above neuropsychological and fMRI findings have provided evidences against the assumption of left hemineglect dyslexia. Instead, they support the mechanism of disconnection of visual word form processing pathway. In conclusion, the evidences suggested that the visual information transmission of characters in the left visual field from right occipital area to the VWFA in the left hemisphere was interrupted by the splenium lesion.Brain Structure and Function 01/2013; · 5.63 Impact Factor -
SourceAvailable from: Xiaomeng Xu
Article: Regional brain activity during early-stage intense romantic love predicted relationship outcomes after 40 months: An fMRI assessment.
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ABSTRACT: Early-stage romantic love is associated with activation in reward and motivation systems of the brain. Can these localized activations, or others, predict long-term relationship stability? We contacted participants from a previous fMRI study of early-stage love by Xu et al. [34] after 40 months from initial assessments. We compared brain activation during the initial assessment at early-stage love for those who were still together at 40 months and those who were apart, and surveyed those still together about their relationship happiness and commitment at 40 months. Six participants who were still with their partners at 40 months (compared to six who had broken up) showed less activation during early-stage love in the medial orbitofrontal cortex, right subcallosal cingulate and right accumbens, regions implicated in long-term love and relationship satisfaction [1,2]. These regions of deactivation at the early stage of love were also negatively correlated with relationship happiness scores collected at 40 months. Other areas involved were the caudate tail, and temporal and parietal lobes. These data are preliminary evidence that neural responses in the early stages of romantic love can predict relationship stability and quality up to 40 months later in the relationship. The brain regions involved suggest that forebrain reward functions may be predictive for relationship stability, as well as regions involved in social evaluation, emotional regulation, and mood.Neuroscience Letters 08/2012; 526(1):33-8. · 2.11 Impact Factor -
Article: Recent developments in multivariate pattern analysis for functional MRI.
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ABSTRACT: Multivariate pattern analysis (MVPA) is a recently-developed approach for functional magnetic resonance imaging (fMRI) data analyses. Compared with the traditional univariate methods, MVPA is more sensitive to subtle changes in multivariate patterns in fMRI data. In this review, we introduce several significant advances in MVPA applications and summarize various combinations of algorithms and parameters in different problem settings. The limitations of MVPA and some critical questions that need to be addressed in future research are also discussed.Neuroscience Bulletin 08/2012; 28(4):399-408. · 1.31 Impact Factor