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The Gateway to the Brain: Dissecting the Primate Eye
Published on: May 27, 2009
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Resolving the organization of the third tier visual cortex in primates: a hypothesis-based approach
Alessandra Angelucci1, Marcello G P Rosa2
1Department of Ophthalmology and Visual Science,Moran Eye Institute,University of Utah,Salt Lake City, Utah 84132.
Visual Neuroscience
|August 5, 2015
Summary
The organization of primate third tier visual cortex is debated. The multiple-areas model, proposing distinct dorsomedial (DM) and ventrolateral posterior (VLP) areas, best explains current evidence in New World primates and homologous regions in macaques and humans.
Area of Science:
- Neuroscience
- Primate Visual Cortex Research
- Comparative Anatomy
Background:
- Ongoing debate exists regarding the number, location, and boundaries of visual areas rostral to the second visual area (V2) in primates.
- This region, known as the
Purpose of the Study:
- To review historical models of third tier visual cortex organization.
- To formulate and compare predictions of these models with experimental evidence.
- To determine the most accurate model for primate third tier cortex organization.
Main Methods:
- Historical overview of proposed models for third tier visual cortex.
- Formulation of specific predictions for each model.
- Comparison of model predictions with experimental data from New World primates, macaques, and humans.
Main Results:
- The
Conclusions:
- The multiple-areas model, positing distinct dorsomedial (DM) and ventrolateral posterior (VLP) areas, is the most consistent with available experimental evidence.
- DM is part of the dorsal visual stream, overlapping with macaque parietooccipital (PO) or V6.
- VLP is part of the ventral visual stream, overlapping with area V3, and evidence contradicts a single elongated V3.
- Homologous third tier cortex organization is proposed for macaques and humans, requiring further hypothesis-driven research.
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