Visual orthographic variation and learning to read across writing systems

要旨

This research examined the extent to which visual characteristics of orthographies affect learning to read within and across writing systems, with an eye toward the role of mapping principles – the manner in which graphemes map to linguistic units (e.g., phonemes, syllables, and morphemes) in this process. Study 1 explained visual orthographic variation by developing a measurement system to quantify complexity of graphemes in 131 orthographies. The results show that grapheme complexity varies across writing systems and that this variation is driven by grapheme inventory, a consequence of mapping principles. Next, we questioned how visual orthographic variation impacts individuals’ perceptual learning of graphemes – one of the initial stages of learning to read. Study 2 tested the degree to which mastering first-language (L1) graphemes with different complexities affects visual perceptual discrimination for individuals using different mapping principles (Online cross-writing-system experiment; eight participant groups: Hebrew, English, Russian, Arabic, Hindi, Telugu, Japanese, and Chinese, n = 60, respectively) and individuals using the same mapping principle (Lab within-writing-system experiment: simplified vs. traditional Chinese, n = 60, respectively). Consistent results from both experiments show that discrimination difficulty is a function of grapheme stimulus complexity itself as well as its relationship to the complexity of participants’ L1, regardless of mapping principles. These results were confirmed in Study 3, in which we developed a universal orthographic neural network encoder focus on statistical properties of visual patterns to simulate human behaviors. We trained each of 131 identical encoders to learn the structure of a different orthography; a strong, positive association was found between grapheme complexity and network learning difficulty. Taken together, our results suggest that visual orthographic variation, encompassing both grapheme complexity and grapheme inventory required for orthographic mastery, affects visual discrimination processing of graphemes; these complexity effects are driven significantly, but not absolutely, by mapping principles across writing systems.

主題