Title
Population receptive field and connectivity properties of the early visual cortex in human albinism
Abstract
In albinism, the pathological decussation of the temporal retinal afferents at the optic chiasm leads to superimposed representations of opposing hemifields in the visual cortex. Here, we assessed the equivalence of the two representations and the cortico-cortical connectivity of the early visual areas. Applying fMRI-based population receptive field (pRF)-mapping (both hemifield and bilateral mapping) and connective field (CF)-modeling, we investigated the early visual cortex in 6 albinotic participants and 4 controls. In albinism, superimposed retinotopic representations of the contra- and ipsilateral visual hemifield were observed on the hemisphere contralateral to the stimulated eye. This was confirmed by the observation of bilateral pRFs during bilateral mapping. Hemifield mapping revealed similar pRF-sizes for both hemifield representations throughout V1 to V3. The typical increase of V1-sampling extent for V3 compared to V2 was not found for the albinotic participants. The similarity of the pRF-sizes for opposing visual hemifield representations highlights the equivalence of the two maps in the early visual cortex. The altered V1-sampling extent in V3 might indicate the adaptation of cortico-cortical connections to visual pathway abnormalities in albinism. These findings thus suggest that conservative developmental mechanisms are complemented by alterations of the extrastriate cortico-cortical connectivity.
Year
DOI
Venue
2019
10.1016/j.neuroimage.2019.116105
NeuroImage
Keywords
Field
DocType
Albinism,Connective field,fMRI,Plasticity,Population receptive field,Visual cortex
Receptive field,Population,Neuroscience,Visual cortex,Biology,Decussation,Albinism,Retinal,Bioinformatics,Optic chiasm
Journal
Volume
ISSN
Citations 
202
1053-8119
1
PageRank 
References 
Authors
0.36
0
6
Name
Order
Citations
PageRank
Khazar Ahmadi141.13
Anne Herbik210.36
Markus Wagner310.36
Martin Kanowski441.72
Hagen Thieme510.36
Michael B. Hoffmann621.09