The fixation distance to the stimulus influences ERP quality:an EEG and eye tracking N400 study

Dominguez Martinez, Estefania and Parise, Eugenio and Strandvall, Tommy and Reid, Vincent (2015) The fixation distance to the stimulus influences ERP quality:an EEG and eye tracking N400 study. PLoS ONE, 10 (7). ISSN 1932-6203

[thumbnail of 2015 Published article]
PDF (2015 Published article)
2015_Published_article.pdf - Published Version
Available under License Creative Commons Attribution.

Download (2MB)


In a typical visual Event Related Potential (ERP) study, the stimulus is presented centrally on the screen. Normally an ERP response will be measured provided that the participant directs their gaze towards the stimulus. The aim of this study was to assess how the N400 component of an ERP was affected when the stimulus was presented in the foveal, parafoveal or peripheral vision of the participant’s visual field. Utilizing stimuli that have previously produced an N400 response to action incongruities, the same stimuli sequences were presented at 0º, 4º, 8º and 12º of visual angle from a fixation location. In addition to the EEG data, eye tracking data were recorded to act as a fixation control method and to allow for eye artifact detection. The results show a significant N400 effect in the right parieto-temporal electrodes within the 0º visual angle condition. For the other conditions, the N400 effect was reduced (4º) or not present (8º and 12º). Our results suggest that the disappearance of the N400 effect with eccentricity is the fixation distance to the stimulus. However, variables like attentional allocation could have also had an impact on the results. This study highlights the importance of presenting a stimulus within the foveal vision of the participant in order to maximize ERP effects related to higher order cognitive processes.

Item Type:
Journal Article
Journal or Publication Title:
Additional Information:
© 2015 Domínguez-Martínez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
Uncontrolled Keywords:
ID Code:
Deposited By:
Deposited On:
04 Aug 2015 09:16
Last Modified:
18 Oct 2023 00:55