The visual word form area engages in processing Braille in expert visual readers

Cerpelloni, Filippo [KU Leuven; UCL] Van Audenhaege, Alice [UCL] Falagiarda, Federica [UCL] Battal, Ceren [UCL] Gau, Remi [UCL] Op de Beeck, Hans [KU Leuven] Collignon, Olivier [UCL] et al.[show all]

In the ventral occipito-temporal cortex (vOTC) reside numerous areas specialized to identify different categories of stimuli. Among them, the visual word form area (VWFA) preferentially responds to written words. What drives this selectivity for orthographic material remains debated. One account suggests that VWFA’s selectivity builds on the intrinsic selectivity for low-level features shared among most orthographic systems, like specific line junctions (e.g. T, L, Y). Alternatively, the VWFA could be sensitive to any alphabetic material, irrespective of these specific low-level features. We present evidence showing that VWFA, in expert visual readers, engages in processing Braille, a script developed for touch that does not share some low-level characteristic of classical alphabets like line junctions. We first show that, in expert visual Braille readers only, the region of vOTC showing preferential activity for roman-based French word over control stimuli, also showed preferential response to Braille words over control Braille stimuli. Second, we presented to the participants stimuli with four decreasing levels of linguistic properties: real words, pseudo-words, non-words, and a fake-script condition, for both Braille and roman-based alphabets. Multivariate analyses on patterns of activity from VWFA revealed that the differences between words and word-like stimuli show a dissimilarity pattern within Braille stimuli that resembles the one within roman-based French. These results indicate that typical visual features of scripts are not mandatory characteristics in the activation of VWFA for linguistic material. Rather, linguistic information itself, invariant across scripts, seems to play an important role in determining the response of this word-selective brain area.