For example, the aksharas म and ल represent/m/and/l/, respectively. Basic CV aksharas contain the inherent vowel sound//or schwa. In Devanagari, the basic unit of writing is called akshara, which is alphasyllabic because it represents approximately one spoken syllable containing two phonemes (sounds) – one consonant and one vowel, that is, CV in contrast, letters or graphemes in English represent single phonemes. While Hindi is used by over 200 million people in South Asia, the Devanagari script is used to write several languages in North India, including Hindi, Sanskrit, Marathi, Nepali, and Konkani. The Devanagari script used to write Hindi is an alphasyllabary and a descendent of the Brahmi script. Like alphabetic systems, alphasyllabaries distinguish vowels and consonants, and like syllabic systems, the grapheme is mapped to a syllable. An alphasyllabary has features of both the alphabetic and the syllabic writing systems. In this paper, we discuss Devanagari, which is an alphasyllabary. Additionally, these studies have also shown that for visually complex scripts like Chinese, Korean, and Japanese Kana, there is increased bilateral involvement wherein activation of right hemisphere regions including the right homolog of the visual word form area (BA37), parietal cortex (BA7), as well as right superior and middle frontal gyri (BA9/8) has been attributed to the processing of complex visuospatial information. Studies on syllabic writing systems have been limited, but consistently report activation in the inferior parietal lobule (BA40). Reading in an alphabetic writing system, for instance, shows the involvement of the temporo-parietal region (BA21/39), while reading in Chinese invokes activation in the middle frontal gyrus (BA9/46). However, extensive research on reading in these different writing systems has also identified specific cortical areas consistently associated with reading in a specific writing system. Three general regions emerge as highly convergent across all writing systems, namely, the left superior posterior superior temporal gyrus (BA21/22), the left inferior frontal gyrus (BA6), and the left occipitotemporal region and mid-fusiform gyrus (BA19/37) which has also been termed the visual word form area. Despite these differences, a host of studies on word recognition in Chinese, English, and Japanese Kana have shown the activation of a common cortical network, primarily in the left hemisphere, for all writing systems. The logographic system used in Chinese is completely different in that it maps a logographic character to a meaningful unit (a morpheme or word) that is also a spoken syllable. Therefore, a basic question of investigation has been, “Does a unified processing system for different writing systems exist, or are there differences?” In an alphabetic writing system like English or German, a grapheme is mapped to a phoneme, whereas in a syllabic writing system like Japanese Kana, a grapheme is mapped to a spoken syllable. The principles of a writing system reflect fundamental writing–language relationships which vary widely on the dimensions of level of representation/grain size, transparency, and spatial layout. Writing systems of the world may broadly be classified as alphabetic (English), syllabic (Japanese Kana), and logographic (Chinese). It is this influence that shapes culture-specific cortical differences between various writing systems. According to the neuronal recycling hypothesis proposed by Dehaene and Cohen, such adaptation of existing cortical mechanisms to new functions does not override the previous principles of organization instead, the newly developed specialization is heavily influenced by older cortical capacities and constraints. Reading is acquired through formal instruction, and the neural network for reading is thought to develop by adapting already existing visual, auditory and language networks to serve a novel cognitive function.
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