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Updated: Aug 6, 2026
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Functional Magnetic Resonance Imaging (fMRI) of the Visual Cortex with Wide-View Retinotopic Stimulation
Published on: December 8, 2023
Wide-field retinotopy defines human cortical visual area v6
Sabrina Pitzalis1, Claudio Galletti, Ruey-Song Huang
1NeuroImaging Laboratory, Santa Lucia Foundation, Istituto di Ricovero e Cura a Carattere Scientifico, 00179 Rome, Italy.
Summary
Researchers mapped a new human visual area using fMRI and identified its retinotopic organization. This area, potentially the human V6, represents the contralateral visual hemifield and includes a distinct center of gaze representation.
Area of Science:
- Neuroscience
- Visual Neuroscience
- Human Brain Mapping
Background:
- The human visual cortex contains numerous specialized areas.
- Understanding the complete map of human visual areas is crucial for cognitive neuroscience.
- The dorsal parieto-occipital sulcus is a region with incompletely characterized visual areas.
Purpose of the Study:
- To identify and characterize the retinotopic organization of a novel visual area in the human brain.
- To determine the location and functional properties of this new area relative to known visual areas.
- To investigate the potential homology of this area with visual areas in non-human primates.
Main Methods:
- High-field functional magnetic resonance imaging (fMRI) was employed to map brain activity.
- Cortical surface-based analysis was used to precisely delineate the visual area.
- Wide-field retinotopic stimulation was utilized to define the visual field representation.
Main Results:
- A consistent retinotopic visual area was identified in all 34 subjects studied.
- This area, located near the midline in the dorsal parieto-occipital sulcus, represents the contralateral visual hemifield.
- It exhibits a distinct representation of the center of gaze, a large peripheral field representation, and a mirror-image visual field map, adjacent to areas V2/V3 and V3/V3A.
Conclusions:
- The newly identified visual area shows characteristics suggesting it is the human homolog of macaque area V6.
- It may also correspond to areas M or DM in New World primates.
- This finding expands our understanding of the human visual processing network.
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