Cognitive underpinnings of multidimensional Japanese literacy and its impact on higher-level language skills

Abstract

This study aimed to identify the cognitive underpinnings of Japanese kanji abilities and clarify the contributions of kanji acquisition to the development of higher-level language skills based on a three-dimensional view of kanji abilities encompassing reading accuracy, writing accuracy, and semantic comprehension. First, a series of regression analyses was used to identify the multifactorial models of each dimension of Japanese kanji acquisition. These models suggest that, among basic cognitive skills, naming speed, visuospatial processing, and syntactic processing underpin kanji abilities in a dimension-specific manner, whereas phonological processing is a common factor. Second, although all the dimensions of kanji abilities predicted acquired verbal knowledge equally, writing skills on the text level, measured as idea density, were only predicted by the writing dimension (indirectly via acquired knowledge). Our findings represent the first evidence of the dimension-specific relationships of the three dimensions of Japanese kanji abilities with their cognitive predictors, as well as with higher-level language skills. They suggest the importance of handwriting acquisition during school years for the development of language skills through to adulthood. Finally, taking the seminal “Nun study,” which suggests that higher idea density is protective against dementia, into account, we propose a theoretical framework for the lifelong trajectory of literacy acquisition.

The unique contribution of handwriting accuracy to literacy skills in Japanese adolescents

“…Our results suggested that word-level comprehension and writing skills acquired during school years underpinned the development of text-level reading and writing proficiency, respectively and dimension-specifically, and the former underlies the latter. This was consistent with accumulated knowledge (Abbott et al, 2010 ; Ahmed et al, 2014 ; Bourke et al, 2014 ; Kim, 2017 , 2020 ; Kim & Graham, 2022 ; Otsuka & Murai, 2021 ; Yeung et al, 2013 ). Furthermore, the significantly large value of the modification index in Model 3 shown with validation data 2 clearly indicated that the contribution of word handwriting skills to text writing proficiency cannot be replaced by the semantic comprehension of words.…”

“…The three dimensions of word-level Japanese literacy skills reflect phonological, orthographic, and semantic processing, which are required to master Japanese kanji characters that have multiple pronunciations, visual complexity, and different meanings. The multidimensional nature of word literacy, based on dimension-specific and common cognitive underpinnings (Otsuka & Murai, 2021 ), implies educational or therapeutic strategies may be necessary depending on the dimensions and causes of difficulties in literacy acquisition.…”

“…Therefore, the kanji-to-kana conversion is usually used in literacy education in Japan. Each correct item was awarded 1 point, with a maximum score of 30 for both Level 3 and Pre-2 (0–30; Otsuka & Murai, 2020 , 2021 ). Semantic comprehension …”

“…There were 10 items and 10 kana word options, as for Level 3. Each correct item was awarded 2 points, giving a maximum score of 20 (0–20; Otsuka & Murai, 2020 , 2021 ). Writing accuracy …”

“…Word spelling at ages 6–12 predicts text writing in the following years, but not text reading, also except at age 7 (Abbott et al, 2010 ). In addition, a study of Japanese university students (Otsuka & Murai, 2021 ) examined the relationships between word-level reading/writing as well as semantic comprehension and text writing based on the three-dimensional view of word-level literacy (Otsuka & Murai, 2020 ). The authors reported that only the accuracy of word handwriting affected text writing via knowledge acquisition.…”