Human V2A: A map of the peripheral visual hemifield with functional connections to scene-selective cortex

Area of Science:

• Neuroscience
• Human visual perception
• Cortical organization

Background:

• Gist-based visual scene perception relies on specialized visual processing, likely involving the visual periphery.
• This processing is hypothesized to occur at a low level in the visual hierarchy.

Purpose of the Study:

• To identify the specific cortical locus for initial stages of gist-based visual scene perception.
• To characterize the receptive field properties and connectivity of this newly identified visual area.

Main Methods:

• Wide-field retinotopic mapping
• Population receptive field (pRF) modeling
• Resting-state functional MRI (fMRI) connectivity analysis

Main Results:

• A novel visual hemifield map, termed area V2A, was identified anterior to V2d and inferior to V6.
• V2A exhibits large (FWHM ~23°) and constant receptive field sizes across a wide visual field (central ~70°).
• Connectivity analysis suggests V2A rapidly feeds scene-processing networks with non-center-biased visual information.

Conclusions:

• Area V2A is a likely cortical locus for early gist-based visual scene perception.
• Findings suggest a reappraisal of human dorsomedial occipital cortex organization, revealing hemifield representations anterior to early visual areas.
• V2A's properties are well-suited for rapid scene understanding by processing peripheral visual information.