Steady state visual evoked potentials in reading aloud: Effects of lexicality, frequency and orthographic familiarity

Veronica Montani,Valerie Chanoine,Ivilin Peev Stoianov,Jonathan Grainger,Johannes C Ziegler

doi:10.1016/j.bandl.2019.01.004

Abstract

The present study explored the possibility to use Steady-State Visual Evoked Potentials (SSVEPs) as a tool to investigate the core mechanisms in visual word recognition. In particular, we investigated three benchmark effects of reading aloud: lexicality (words vs. pseudowords), frequency (high-frequency vs. low-frequency words), and orthographic familiarity (‘familiar’ versus ‘unfamiliar’ pseudowords). We found that words and pseudowords elicited robust SSVEPs. Words showed larger SSVEPs than pseudowords and high-frequency words showed larger SSVEPs than low-frequency words. SSVEPs were not sensitive to orthographic familiarity. We further localized the neural generators of the SSVEP effects. The lexicality effect was located in areas associated with early level of visual processing, i.e. in the right occipital lobe and in the right precuneus. Pseudowords produced more activation than words in left sensorimotor areas, rolandic operculum, insula, supramarginal gyrus and in the right temporal gyrus. These areas are devoted to speech processing and/or spelling-to-sound conversion. The frequency effect involved the left temporal pole and orbitofrontal cortex, areas previously implicated in semantic processing and stimulus-response associations respectively, and the right postcentral and parietal inferior gyri, possibly indicating the involvement of the right attentional network.

Highlights

The steady state visual evoked potentials (SSVEPs) are the electrophysiological response of the cortex to flickering visual stimuli (Regan, 1989; for recent reviews, see Norcia, Appelbaum, Ales, Cottereau, & Rossion, 2015, and Vialatte, Maurice, Dauwels, & Cichocki, 2010)
The SSVEP response modulation could arise from different processes (Bergholz, Lehmann, Fritz, & Ruther, 2008; Rossion, & Boremanse, 2011), it is generally assumed that larger SSVEP responses are caused by more efficient network dynamics (Zhang, Guo, Cheng, Yao, & Xu, 2015)
Nonwords with familiar letter patterns are typically read faster than nonwords with unfamiliar letter patterns. Both lexicality and frequency effects have been extensively investigated with standard event-related brain potentials (ERPs) in studies that focused on the time course of visual word recognition (e.g., Barber & Kutas, 2007; Grainger & Holcomb, 2009)

Summary

Introduction

The steady state visual evoked potentials (SSVEPs) are the electrophysiological response of the cortex to flickering visual stimuli (Regan, 1989; for recent reviews, see Norcia, Appelbaum, Ales, Cottereau, & Rossion, 2015, and Vialatte, Maurice, Dauwels, & Cichocki, 2010). Heinrich, Mell, & Bach, 2009; Liu-Shuang, Norcia, & Rossion, 2014), in which they presented words interspersed at regular intervals in sequences of either pseudowords, nonwords, or false fonts They found significant SSVEP activity at the presentation frequency of words in all conditions, demonstrating that words generate a clear SSVEP response in the oddball paradigm. Nonwords with familiar letter patterns (high bigram frequency or many orthographic neighbors) are typically read faster than nonwords with unfamiliar letter patterns Both lexicality and frequency effects have been extensively investigated with standard event-related brain potentials (ERPs) in studies that focused on the time course of visual word recognition (e.g., Barber & Kutas, 2007; Grainger & Holcomb, 2009). In order to further consolidate our approach, we compared our results with those of previous studies that have attempted to dissociate the neural pathways of the reading network

Participants

Apparatus and stimuli

Procedure

EEG recording and analysis

Results

Discussion

25 Acknowledgments