Characterizing visual cortical magnification with topological smoothing and optimal transportation

Area of Science:

• Neuroscience
• Visual Neuroscience
• Computational Neuroscience

Background:

• Human visual perception exhibits varying concentration across visual fields.
• The cortical magnification factor (CMF) is a key metric for visual acuity and cortical processing.
• Existing methods struggle to comprehensively measure CMF across the entire visual field.

Purpose of the Study:

• To develop and validate a novel method for measuring planar CMF across the whole visual field.
• To enhance the accuracy and topological integrity of retinotopic maps for CMF calculation.
• To investigate novel concentration behaviors and individual variations in visual field representation.

Main Methods:

• Proposed a pipeline integrating optimal transportation and topological smoothing for retinotopic map generation.
• Optimal transportation refines vertex locations in retinotopic mapping.
• Topological smoothing ensures map integrity, enabling planar CMF calculation via a 1-ring patch method.

Main Results:

• Successfully applied the pipeline to the HCP 7T dataset, analyzing 181 subjects.
• Generated novel planar CMF measurements across the entire visual field.
• Identified previously undocumented concentration behaviors and significant individual differences in visual field representation.

Conclusions:

• The proposed method provides a robust approach for comprehensive planar CMF measurement.
• The findings offer new insights into the organization and individual variability of the human visual cortex.
• This work advances our understanding of visual field processing and its neural underpinnings.