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Updated: Apr 30, 2026
Assessing Binocular Central Visual Field and Binocular Eye Movements in a Dichoptic Viewing Condition
Published on: July 21, 2020
A frequency-tagging electrophysiological method to identify central and peripheral visual field deficits
Noémie Hébert-Lalonde1, Lionel Carmant, Dima Safi
1Département de psychologie, Université de Montréal, Montréal, QC, Canada.
Insights
This study developed a fast electrophysiological protocol using steady-state visual-evoked potentials (ssVEPs) to assess visual field integrity in children and adults. The method is efficient and reliable for pediatric testing.
Area of Science:
- Ophthalmology
- Neuroscience
- Clinical Electrophysiology
Background:
- Assessing visual field integrity is crucial, especially in pediatric populations.
- Existing methods can be time-consuming and challenging for young children.
- A need exists for a rapid and efficient electrophysiological protocol for visual field testing.
Purpose of the Study:
- To develop and validate a fast and efficient electrophysiological protocol for examining visual field integrity.
- To assess the protocol's utility in pediatric testing.
- To evaluate the impact of age and gaze deviation on the electrophysiological signals.
Main Methods:
- Utilized steady-state visual-evoked potentials (ssVEPs) with field-specific radial checkerboards at 7.5 Hz (central) and 6 Hz (peripheral).
- Recorded responses from 22 healthy participants (5-34 years) and 5 visually impaired adolescents.
- Investigated responses at multiple electrode sites (Oz, POz, O1, O2) and the effect of gaze deviation.
Main Results:
- ssVEP responses were consistent across electrode sites, with a stronger central signal at Oz.
- The protocol demonstrated high sensitivity in detecting gaze deviation.
- No significant effects of age or sex were observed in healthy participants; visual acuity correlated with the central signal.
Conclusions:
- A single electrode at Oz is sufficient for capturing central and peripheral visual signals and monitoring gaze deviation.
- The developed ssVEP protocol is fast, reliable, efficient, and suitable for children as young as 5.
- Further studies with larger pediatric cohorts are recommended to establish clinical norms.
Background:
The aim of this study was to develop a fast and efficient electrophysiological protocol to examine the visual field's integrity, which would be useful in pediatric testing.
Methods:
Steady-state visual-evoked potentials (ssVEPs) to field-specific radial checkerboards flickering at two cycle frequencies (7.5 and 6 Hz for central and peripheral stimulations, respectively) recorded at Oz were collected from 22 participants from 5 to 34 years old and from 5 visually impaired adolescents (12-16 years old). Responses from additional leads (POz, O1, O2), and the impact of gaze deviation on the signals, were also investigated in a subgroup of participants.
Results:
Steady-state visual-evoked potentials responses were similar at all electrode sites, although the signal from the central stimulation was significantly higher at Oz and was highly sensitive in detecting gaze deviation. No effect of age or sex was found, indicating similar ssVEP responses between adults and healthy children. Visual acuity was related to the central signal when comparing healthy participants with four central visual impaired adolescents. Clinical validation of our electrophysiological protocol was also achieved in a 15-year-old adolescent with a severe peripheral visual deficit, as assessed with Goldmann perimetry.
Conclusions:
A single electrode over Oz is sufficient to gather both central and peripheral visual signals and also to control for gaze deviation. Our method presents several advantages in evaluating visual fields integrity, as it is fast, reliable, and efficient, and applicable in children as young as 5 years old. However, a larger sample of healthy children should be tested to establish clinical norms.
