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Updated: May 15, 2026
09:42
Stimulus-specific Cortical Visual Evoked Potential Morphological Patterns
Published on: May 12, 2019
VEP correlates of feedback in human cortex
Yury Petrov1, Jeffrey Nador, Jiehui Qian
1Psychology Department, Northeastern University, Boston, Massachussets, USA. y.petrov@neu.edu
Plos One
|December 20, 2012
Summary
This study investigated neural feedback in visually evoked potentials (VEP) using EEG. Findings suggest feedback from higher visual areas significantly influences early visual processing reactivations.
Area of Science:
- Neuroscience
- Visual Perception
- Electrophysiology
Background:
- Neural responses typically show decreased stimulus size and location dependency along the visual pathway.
- Understanding neural feedback mechanisms is crucial for comprehending visual information processing.
Purpose of the Study:
- To leverage the property of reduced stimulus dependency to find evidence of neural feedback in visually evoked potentials (VEP).
- To analyze the spatial and temporal characteristics of VEPs to infer feedback pathways.
Main Methods:
- Collected high-density VEPs from 15 observers using a 128-channel EEG system with a contrast-reversing checkerboard stimulus.
- Applied the Surface Laplacian method to derive skull-scalp currents from measured potentials.
- Analyzed response nonlinearity and laterality across different scalp regions and peak latencies.
Main Results:
- Response nonlinearity increased from occipital to temporal regions and with peak latency in reactivations.
- Early lateral-occipital responses were contralateral, but later responses showed decreased or absent laterality.
- Temporal responses showed no significant difference between contralateral and ipsilateral stimulation.
Conclusions:
- The observed patterns of nonlinearity and laterality in VEPs support the involvement of neural feedback.
- Feedback from higher visual areas, such as temporal cortices, likely contributes to reactivations in early visual processing areas.
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