Functional organization of the second cortical visual area in primates

Area of Science:

• Neuroscience
• Visual System Anatomy
• Cortical Organization

Background:

• The functional organization of extrastriate visual areas is crucial for understanding visual processing.
• Previous studies in the primary visual cortex revealed modular organization using anatomical markers.

Purpose of the Study:

• To investigate the functional organization of the second cortical visual area (V2).
• To identify anatomical criteria for defining the borders of V2.
• To compare the modular organization of V2 with that of the primary visual cortex (V1).

Main Methods:

• Utilized three anatomical markers: 2-[14C]deoxy-D-glucose, cytochrome oxidase, and myelin stains.
• Examined the distribution of these markers within the second cortical visual area.
• Compared findings in V2 with existing data from V1 in macaques.

Main Results:

• All three markers revealed distinct parallel strips running throughout the second cortical visual area.
• The boundaries of these strips served as anatomical criteria for defining V2 borders.
• Structural and functional differences were observed between these strips and interstrip regions, mirroring V1 organization.
• Differences in binocular organization were noted between V2 strips and V1 spots in macaques.

Conclusions:

• The second cortical visual area exhibits a modular organization characterized by distinct anatomical and functional strips.
• These strips provide a basis for defining V2 boundaries and analyzing its functional architecture.
• The findings suggest similarities and differences in modular organization between V2 and V1, particularly regarding binocular processing.