Abstract
Learning to read specializes a portion of the left mid-fusiform cortex for printed word recognition, the putative "visual word form area" (VWFA). This study examined whether a VWFA specialized for English is sufficiently malleable to support learning a perceptually atypical second writing system. The study utilized an artificial orthography, "HouseFont," in which house images represent English phonemes. House images elicit category-biased activation in a spatially distinct brain region, the so-called "parahippocampal place area" (PPA). Using house images as letters made it possible to test whether the capacity for learning a second writing system involves neural territory that supports reading in the first writing system, or neural territory tuned for the visual features of the new orthography. Twelve human adults completed two-weeks of training to establish basic HouseFont reading proficiency and underwent functional neuroimaging pre and post-training. Analysis of three functionally defined regions of interest, the VWFA, and left and right PPA, found significant pre- versus post-training increases in response to HouseFont words only in the VWFA. Analysis of the relationship between the behavioral and neural data found that activation changes from pre- to post-training within the VWFA predicted HouseFont reading speed. These results demonstrate that learning a new orthography utilizes neural territory previously specialized by the acquisition of a native writing system. Further, they suggest VWFA engagement is driven by orthographic functionality and not the visual characteristics of graphemes, which informs the broader debate about the nature of category-specialized areas in visual association cortex.
Significance Statement Fluent reading recruits a portion of the brain known as the visual word form area (VWFA), but it is less well understood how malleable the VWFA remains after acquiring literacy in a native language. There is also debate about the type of visual information the VWFA can process as orthographically meaningful. We tested whether native English-speaking adults could learn a second, visually atypical writing system for English and used neuroimaging data to assess the location of any learning effects. Participants acquired basic reading ability and learning effects were found in the neural territory that underlies English reading. This suggests that the VWFA remains plastic after initial literacy and is not restricted by the visual features of a writing system.
Footnotes
No. Authors report no conflict of interest.
This work was supported by the National Institute of Health R01 HD060388.
This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license, which permits unrestricted use, distribution and reproduction in any medium provided that the original work is properly attributed.
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