| 摘要: | 初生嬰兒所擁有的基本數學能力，似乎說明人類對數量之瞭解是一種與生俱來的本能。然而，學齡中的兒童卻往往視數學為一困難科目，少數個案甚至表現出嚴重落後正常發展進程的數學障礙。由於空間能力的缺失被研究者一致認為在某主要的數學障礙亞型中扮演關鍵的角色，本研究提議利用以雙手對刺激材料作按鍵反應的實驗派典，來檢驗在大學生心中不同符號系統中的數字和序列訊息表徵是否具有與空間對應的特性，以及此一對應關係是否受到語言環境的影響（實驗一至四）。實驗五和六以眼動儀監控受試者之眼球運動，探討受試者之內隱注意力在空間中的分佈，是否會受不同符號系統中的數字大小所影響。實驗七和八則是以腦磁波儀紀錄受試者在處理數字時，腦中負責內隱注意力和準備執行按鍵反應的神經機制，是否會受到所見數字數量大小的調節。最後，實驗九至十二將採用和實驗一至四相同的研究方法，探討相同操弄在正常發展和具有數學障礙之孩童身上的效果，對照來自大學生的資料，以建立數字和序列訊息與空間形成對應此一現象的發展趨勢。本研究所提出的一系列實驗，可增加我們對數字表徵及其處理歷程的瞭解，進一步釐清空間訊息對數學理解的重要性，更有助於發展矯正數學障礙的補救措施。 Mathematical cognition seems to be an innate ability to humans, as basic understanding of numbers is observed in infants at very young ages. Paradoxically, arithmetical skills are among the most difficult subjects for school children and, in severe cases, children with developmental dyscalculia (DD) fail to achieve the performance level as other normally developing controls. Given the different characteristics demonstrated by children with DD, it is argued that this developmental disorder is a heterogeneous label with subtypes. Although previous literature does not agree on the categorization of these subtypes, the importance of the visuospatial ability has been consistently highlighted. Following this consensus, it is assumed that the spatial aspects are critical to the representation and processing of numbers. This assumption has received support from behavioral and neurophysiological findings. However, such spatial mapping is not only observed in numerical but also in ordinal information. Moreover, the orientation of the mapping between numbers and space also seem to be subject to the influence from language experience. To examine the universality of this assumption, whether it can be applied to ordinal information, and its implications to math education, twelve experiments employing the SNARC (Spatial Numerical Association Response Code) effect are proposed in this study. The SNARC effect demonstrates that the manual responses via the left hand are faster to small than to large numbers, while the reversed pattern is found for the manual responses via the right hand. This mapping between numbers and space implies that small to large numbers are represented in the mental space along a left-to-right horizontal line. If this spatial property is number-specific and is part of the core concept of numerical knowledge, it should not be observed in other non-numerical (e.g., ordinal) stimuli, and it should not be influenced by language experience (e.g., the dominantly vertical reading/writing orientation of Chinese text). To empirically test these hypotheses, Experiment 1 to 4 in the proposed study employ the SNARC effect to examine the horizontal and vertical spatial mapping of numerical stimuli in different notations and ordinal information in college students. Experiment 5 and 6 aim to explore the spatial cueing effect of the numerical stimuli in different notations on directing covert attention along the horizontal and vertical mental number lines. Experiment 7 and 8 employ the magnetoencephalography (MEG) to study the neural underpinnings of the spatial cueing effect and the modulations of lateralized readiness potential (LRP) from spatially represented numbers. Finally, Experiment 9 to 12 employ the SNARC effect again to obtain findings parallel to those obtained from Experiment 1 to 4 in normally children and children with developmental dyscalculia (DD). In summary, the proposed experiments hope to elucidate the spatial mapping of numerical and ordinal information in different notations and in different populations, as well as the neural underpinnings of such effects. The results from this study will improve our understanding of the representation and processing of numbers, and help us to develop appropriate remedies for the mathematical difficulties associated with the visuospatial aspects of the numerical knowledge. 研究期間：9608 ~ 9707 |
