MONOBILI - Properties and regularities of orthographies impacting visual word recognition in FPVS-EEG in mono and bilinguals - FHSE

To understand the neural mechanisms underlying word-selective responses in FPVS-EEG, we assess the paradigm across variations of languages, designs and tasks.

The project at a glance

Start date:

15 Mar 2022
Duration in months:

72
Funding:

University of Luxembourg / University of Cambridge Medical Research Council / Université de Lorraine CNRS, IMoPA, Nancy
Principal Investigator(s):

Aliette LOCHY

Christine SCHILTZ

Matthew Lambon Ralph (external)

Bruno Rossion (external)

About

Studies using frequency-tagging in electroencephalography (EEG) have dramatically increased in the past 10 years, in a variety of domains and populations. Here we used Fast Periodic Visual Stimulation (FPVS) combined with an oddball design, in which periodicity of brain responses allow to measure discrimination between two experimentally defined categories of stimuli, to explore visual word recognition. Given the paradigm’s high sensitivity, it is crucial for future basic research to prove its robustness across variations of languages, designs, stimulus types and tasks. Also, combining EEG and MEG neuroimaging techniques will reveal sources of the word-selective responses. First, we will assess the impact of design-related factors like relative frequency of item repetition (set size or item repetition controlled for deviant vs. base stimuli), and of the orthogonal task (focused or deployed spatial attention). These non-linguistic factors could affect word-selective responses because of extraction of statistical regularities in the stimuli, or because of attention variations. Second, we will examine the impact of orthographic transparency and lexical neighborhood density by comparing monolingual English and French-speakers. Next to this language manipulation, we will also vary the neighborhood density in stimuli selection. This will allow to understand if and how lexical responses are modulated as a function of the amount of activation in the orthographic lexicon. The study of French/English bilinguals will inform us on the flexibility of the visual word recognition system to different languages according to language proficiency. Furthermore, by crossing languages in our design, we will address the issue of common vs separated orthographic lexicon in bilinguals. Finally, variations of the paradigm together with source estimation in MEG recordings can provide novel insights into the neural basis of visual word recognition in healthy and clinical populations.