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The change in hypometabolism affects the regional links in the brain network. Here, to understand the underlying brain metabolic network deficits during the early stage and disease evolution of AD (Alzheimer disease), we applied correlation analysis to identify the metabolic connectivity patterns using 18F-FDG PET data for NC (normal control), sMCI (stable MCI), pMCI (progressive MCI) and AD, and explore the inter- and intra-hemispheric connectivity between anatomically-defined brain regions. Regions extracted from 90 anatomical structures were used to construct the matrix for measuring the inter- and intra-hemispheric connectivity. The brain connectivity patterns from the metabolic network show a decreasing trend of inter- and intra-hemispheric connections for NC, sMCI, pMCI and AD. Connection of temporal to the frontal or occipital regions is a characteristic pattern for conversion of NC to MCI, and the density of links in the parietal-occipital network is a differential pattern between sMCI and pMCI. The reduction pattern of inter and intra-hemispheric brain connectivity in the metabolic network depends on the disease stages, and is with a decreasing trend with respect to disease severity. Both frontal-occipital and parietal-occipital connectivity patterns in the metabolic network using 18F-FDG PET are the key feature for differentiating disease groups in AD.

Abstract [18F]9-fluoropropyl-(+)-dihydrotetrabenazine (18F-(+)DTBZ) is a recently developed PET tracer to investigate the vesicular monoamine transporter type 2 (VMAT2) activity in measuring dopaminergic degeneration in vivo and monitoring the severity of Parkinson’s disease (PD). However, manual drawing of the striatal regions is time consuming and prone to human bias. In the current study, we developed an automated method to quantify the signals of the striatum on 18F-(+)DTBZ images. 39 patients with PD and 26 controls were enrolled. Traditional brain magnetic resonance imaging (MRI) and 18F-(+)DTBZ PET were acquired. Both indirect normalization of native PET images to the standard space through individual brain MRI and directly coregistration of native images to the transporter-specific PET template in standard space were performed. Specific uptake ratios (SURs) in 10 predefined regions were used as indicators of VMAT2 activities to correlate with motor severity. Our results showed patients with PD had significant lower SURs in the bilateral putamina, caudates and globus pallidi than controls. SURs in the caudate and putamen were significantly correlated with motor severity. The contralateral putaminal region performed best in discriminating between PD patients and controls. Finally, the results from the application of the 18F-(+)DTBZ PET template were comparable to those derived from the traditional MRI based method. Thus, 18F-(+)DTBZ PET imaging holds the potential to effectively differentiate PD patients from controls. The 18F-(+)DTBZ PET template-based method for automated quantification of presynaptic VMAT2 transporter density is easier to implement and may facilitate efficient, robust and user-independent image analysis.

This study applied storytelling in the English as a foreign language (EFL) classroom in order to promote speaking skills. Students were asked to practice speaking EFL through producing individual and interactive stories with a Web-based multimedia system. We aimed to investigate an effectiveness of applying individual and interactive storytelling on speaking skills and the potential effects of multimedia aids in storytelling to facilitate language learning. Furthermore, we explored the relationships between research variables of this study, such as speaking performance on individual and interactive storytelling, the number of animation representations, and the system actual usage, with learning achievement. Four main findings were found in this study. First, students who used the system for creating stories significantly outperformed students who did not use it on the post-test. This finding suggests that storytelling activity with support of the system was beneficial for improving speaking skills. Second, speaking performance and the number of animation representations significantly correlated with learning achievement. Students who performed well during learning activities usually studied diligently and scored higher on final test. Animations could help students remember vocabulary and practice speaking to describe their animated stories. Third, only the speaking performance on individual storytelling was found as the significant predictor of learning achievement. Students working individually on storytelling were independent; they were less distracted from others, and had more opportunity for practice. The last but not the least, most students expressed positive perceptions and attitude toward the system and learning activities. Based on these findings, we suggest that storytelling learning activities supported by the Web-based multimedia system and implementing them in EFL learning classroom can be beneficial for facilitating speaking skills. Students can remember new vocabulary better, practice speaking skills more frequently, become competent in speaking target language, and improve learning performance.

This study explored the use of self-assessments, journaling, and peer sharing in an online computer programming course. We conducted an experiment using a pretest-intervention-posttest design in which 64 undergraduate first-year students participated. We aimed to investigate whether self-assessment, journaling, and peer sharing can facilitate students' learning. Moreover, we examined how the research variables related to each other and to learning achievement. Therefore, after the experiment, (1) prior knowledge, learning performance, and achievement were assessed, (2) online logs representing learning behaviors were analyzed, and (3) students were interviewed. Results demonstrated that self-assessment, journaling, and peer sharing effectively facilitated learning and students' cognition regulation strategies. Namely, keeping a learning journal enabled students to summarize key concepts, elaborate ideas, and reflect on learning material; self-assessment allowed students to reflect on their understanding of the material under study; and peer sharing enabled students to study peers' learning journals and self-assessments to improve their own. Although self-assessment, journaling, and peer sharing significantly correlated with each other and with learning achievement, results showed that keeping a learning journal had the strongest effect on learning achievement. Moreover, self-assessment and keeping a learning journal complemented each other and combining the two resulted in even higher learning achievement scores. The findings suggest that the use of self-assessment, journaling, and peer sharing show promise to facilitate learning from an online course.

It is apparent that individuals using text abbreviations as a written convention is a continuingly growing phenomenon. This special writing convention has been referred to as textism usage. However, there is surprisingly little research investigating the impacts of textism use on dyslexic children's cognitive abilities associated with literacy skills. Thus, the relation between textism use, phonological awareness, as well as morphological awareness is not yet clear. This issue is critical and urgent because no conclusive guidance is available for practitioners or educators to refine instructional strategies. Furthermore, given that prior researchers focus mainly on alphabetic language, little research draws attention on non-alphabetic language, in which morphological awareness seems rather significant than phonological awareness. In this study a total of 57 participants across six elementary schools in Taiwan were recruited and were formed into three groups. To effectively collect the textisms used by the participants, this study adopted Facebook as the tool to store the messages because of its high penetration rate of 51 percent in Taiwan. Findings of this study suggested that dyslexic children may get rid of the identification, which might encourage them shift their focuses from others' judgment to selecting a proper textism. To use the textism appropriately requires the dyslexic children realize the meaning of the textism and memorize the spelling/writing convention. Consequently, the dyslexia group in this study performed as well as reading-age group in word recognition and meaning recognition. It seemed that dyslexic children preferred to use contraction, symbol, and combined word. These categories of textism are L-S (logography to semantics) in nature. (Contains 5 tables.)