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Examine visual lateralization of Chinese characters using a bilateral visual presentation protocol and fMRI Chun-Yu, Chen The goal of this study is to examine neural and psychological basis of visual lateralization of Chinese single-character and two-character word using a bilateral visual presentation protocol and fMRI. Chinese characters were simultaneously, bilaterally presented to the participants, one in the LVF and one in the RVF. On the same (visual) presentation frame, there was a central cue (< or >) accompanying the two characters to indicate which character (the LVF one or the RVF one) to attend and process for lexical decision. For robustness checking, frequency of the characters was included as a variable and varied (low, medium, and high). Results of single-character and two-character word conditions show opposite processing profiles in the left and right visual target assignment. That is, while a LVF/RH advantage was revealed in the single-character condition, a RVF/LH advantage was found for the two-character word condition. Our findings are consistent with the behavioral data previously reported (Tzeng et al., 1979). Keywords: left visual field (LVF) superiority, Chinese character, fmri Analysis of Speech Perception and Cortical Auditory Evoked Potentials in Mandarin Sensorineural Hearing Loss with Cochlear Dead Region Sung-Yue Lin1, Guo-She Lee2, 3, Wen-Jui Kuo1 1Institute of Neuroscience, National Yang-Ming University, Taipei, Taiwan. 2Faculty of Medicine and Institute of Brain Science, School of Medicine National Yang-Ming University 3Department of Otorhinolaryngology, Ren-Ai Branch, Taipei City Hospital Abstract In a tonal language, the identity of a word depends largely on the tonal identification of the contour of vocal fundamental frequency energy of which usually centers in a low frequency of less than 600 Hz. However, cochlear dead region (DR) is present mostly in the frequency range of 2000 Hz to 4000 Hz, and the effect of DR on a tonal language is worth investigating. Thirty-two native Mandarin speakers with moderate-to-severe degree of sensorineural hearing loss were included in this study. The pure-tone audiometry, speech recognition threshold (SRT) and word recognition score (WRS) were used to evaluate the degree of hearing loss and word recognition. On the other hand this study is the first to take advantage of cortical auditory evoked potential system ( CAEP), can detect the cerebral cortex to detect changes in clinical speech perception examination ,and reaching an objective verification of complex hearing aids hearing impairment is. The threshold equalizing noise (TEN) tests were used to identify the presence of DR. The results showed that most DRs were present in high frequencies. The hearing thresholds of the ears with a DR were not significantly different from those without DR. However, the WRS was significantly worse for the DR ears, especially for those whose DR included three or more audiometric frequencies. A DR caused a significantly worse word recognition for the tonal language speakers of Mandarin in Taiwan, although the DR frequency occurred in the high frequency of 2000 Hz to 4000 Hz. Key Words: cochlear dead region, Mandarin Chinese in Taiwan, sensorineural hearing loss, threshold equalizing noise, tonal language, word recognition, cortical auditory evoked potential system ( CAEP) Integrating prior knowledge and data: The neural basis of judgment under ambiguity. Chih-Chung, Ting Advisor: Shih-Wei, Wu Abstract We examine how neural systems compute the probabilities of possible outcomes given prior information about probability as well as immediate sensory evidence in the form of a likelihood function. Bayesian decision theory provides a normative model for integrating prior and likelihood to arrive at the posterior probability of each outcome. We designed a novel lottery decision task to investigate how the brain represents priors, likelihood functions based on immediate sensory evidence, and their integration as a posterior. Using functional magnetic resonance imaging (fMRI) we found evidence for representation of priors and integration computations in the medial prefrontal cortex (mPFC), while the inferior parietal lobule (IPL) encodes the level of uncertainty about reward probability conveyed through immediate sensory evidence. Connectivity analysis revealed that during valuation there was an increase in functional connectivity between mPFC and IPL, indicating that information about likelihood is communicated through this frontal-parietal network for integration. Together, these results demonstrate distinct neural systems for representing prior knowledge and sensory evidence about reward statistics, and highlight a candidate neural mechanism that integrates the two during valuation.