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ObjectiveIndividuals with migraine exhibit heightened sensitivity to visual input that continues beyond their migraine episodes. However, the contribution of color to visual sensitivity, and how it relates to neural activity, has largely been unexplored in these individuals. BackgroundPreviously, it has been shown that, in non‐migraine individuals, patterns with greater chromaticity separation evoked greater cortical activity, regardless of hue, even when colors were isoluminant. Therefore, to investigate whether individuals with migraine experienced increased visual sensitivity, we compared the behavioral and neural responses to chromatic patterns of increasing separation in migraine and non‐migraine individuals. MethodsSeventeen individuals with migraine (12 with aura) and 18 headache‐free controls viewed pairs of colored horizontal grating patterns that varied in chromaticity separation. Color pairs were either blue‐green, red‐green, or red‐blue. Participants rated the discomfort of the gratings and electroencephalogram was recorded simultaneously. ResultsBoth groups showed increased discomfort ratings and larger N1/N2 event‐related potentials (ERPs) with greater chromaticity separation, which is consistent with increased cortical excitability. However, individuals with migraine rated gratings as being disproportionately uncomfortable and exhibited greater effects of chromaticity separation in ERP amplitude across occipital and parietal electrodes. Ratings of discomfort and ERPs were smaller in response to the blue‐green color pairs than the red‐green and red‐blue gratings, but this was to an equivalent degree across the 2 groups. ConclusionsTogether, these findings indicate that greater chromaticity separation increases neural excitation, and that this effect is heightened in migraine, consistent with the theory that hyper‐excitability of the visual system is a key signature of migraine.
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Pattern forming mechanisms of color vision
Abstract While our understanding of the way single neurons process chromatic stimuli in the early visual pathway has advanced significantly in recent years, we do not yet know how these cells interact to form stable representations of hue. Drawing on physiological studies, we offer a dynamical model of how the primary visual cortex tunes for color, hinged on intracortical interactions and emergent network effects. After detailing the evolution of network activity through analytical and numerical approaches, we discuss the effects of the model’s cortical parameters on the selectivity of the tuning curves. In particular, we explore the role of the model’s thresholding nonlinearity in enhancing hue selectivity by expanding the region of stability, allowing for the precise encoding of chromatic stimuli in early vision. Finally, in the absence of a stimulus, the model is capable of explaining hallucinatory color perception via a Turing-like mechanism of biological pattern formation.
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- Award ID(s):
- 2052109
- PAR ID:
- 10382815
- Publisher / Repository:
- DOI PREFIX: 10.1162
- Date Published:
- Journal Name:
- Network Neuroscience
- Volume:
- 7
- Issue:
- 2
- ISSN:
- 2472-1751
- Page Range / eLocation ID:
- p. 679-711
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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