Typical and Atypical Development of Visual Expertise for Print as Indexed by the Visual Word N1 (N170w): A Systematic Review

Abstract

The visual word N1 (N170w) is an early brain ERP component that has been found to be a neurophysiological marker for print expertise, which is a prelexical requirement associated with reading development. To date, no other review has assimilated existing research on reading difficulties and atypical development of processes reflected in the N170w response. Hence, this systematic review synthesized results and evaluated neurophysiological and experimental procedures across different studies about visual print expertise in reading development. Literature databases were examined for relevant studies from 1995 to 2020 investigating the N170w response in individuals with or without reading disorders. To capture the development of the N170w related to reading, results were compared between three different age groups: pre-literate children, school-aged children, and young adults. The majority of available N170w studies (N = 69) investigated adults (n = 31) followed by children (school-aged: n = 21; pre-literate: n = 4) and adolescents (n = 1) while some studies investigated a combination of these age groups (n = 12). Most studies were conducted with German-speaking populations (n = 17), followed by English (n = 15) and Chinese (n = 14) speaking participants. The N170w was primarily investigated using a combination of words, pseudowords, and symbols (n = 20) and mostly used repetition-detection (n = 16) or lexical-decision tasks (n = 16). Different studies posed huge variability in selecting electrode sites for analysis; however, most focused on P7, P8, and O1 sites of the international 10–20 system. Most of the studies in adults have found a more negative N170w in controls than poor readers, whereas in children, the results have been mixed. In typical readers, N170w ranged from having a bilateral distribution to a left-hemispheric dominance throughout development, whereas in young, poor readers, the response was mainly right-lateralized and then remained in a bilateral distribution. Moreover, the N170w latency has varied according to age group, with adults having an earlier onset yet with shorter latency than school-aged and pre-literate children. This systematic review provides a comprehensive picture of the development of print expertise as indexed by the N170w across age groups and reading abilities and discusses theoretical and methodological differences and challenges in the field, aiming to guide future research.Systematic Review Registrationhttps://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021228444.

Improvement of semantic processing ability of Chinese characters in school children: A comparative study based on 2009 and 2019 data

“…The results showed that the main effect of recording year was not significant (F (1,531) = 0.332, p = 0.565), and the interaction of recording year with Age and Stimulus Type was not significant (F (4,531) = 1.966, p = 0.098; F (2,531) = 0.067, p = 0.935), and there was no interaction between the three factors (F (8,531) = 0.254, p = 0.980). The main effect of Age was significant (F (4,531) = 11.443, p < 0.001), which was consistent with previous studies that N1 decreased with children development (Amora et al, 2022). However, our results further showed that there was no significant difference in N1 amplitude between 2009 and 2019 recording group, suggesting that the basic visual processing development is similar between the two groups.…”

“…This is similar to the development curve of the visual N170 component associated with expertise for visual stimuli such as words. Longitudinal studies have shown an inverted U-shape development curve of the N170, with an increased response for orthographic stimuli in beginning readers followed by a slight decrease when readers become fluent ( Fraga-Gonzalez et al, 2021 ; Amora et al, 2022 ). Developmental data suggested an inverted U-shape trajectory of visual responses discriminating between words and symbols ( Maurer et al, 2006 ).…”

Specifying precision in visual-orthographic prediction error representations for a better understanding of efficient reading

“…This effect is similar to the previously identified occipitotemporal N170 component, which was interpreted as an earlier maker of visual-orthographic processes in visual word recognition (i.e., differentiates between orthographic stimuli other stimuli such as symbols and faces Carreiras et al (2014); Dehaene, Cohen, Sigman, and Vinckier (2005); Solomyak and Marantz (2009)). Studies focusing on the N170 component (see Amora et al, 2022; Pickering & Gambi, 2018 for a systematic review) also reported that N170 activity may correspond to logographic processing where a word is processed as a whole during the reading of very frequent words or after a massive repetition of a word (Simon, Petit, Bernard, & Rebäi, 2007). However, such findings are hardly found consistently across studies (Nieuwland, 2019).…”

ERP Indicators of Phonological Awareness Development in Children: A Systematic Review

“…Some earlier components have also been shown to be predictive of reading skills, such as the N170 response, which reflects experience with visual words. Reading expertise leads to left lateralization of the N170 response in both alphabetic and logographic scripts [31,32], driven by script familiarity. Children also have a different CNV response in rhyming tasks compared to adults, as the CNV amplitude lowers with age [20].…”