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Updated: Jun 25, 2025
09:49
Methods to Explore the Influence of Top-down Visual Processes on Motor Behavior
Published on: April 16, 2014
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Insights from the Evolving Model of Two Cortical Visual Pathways
Chris Baker1, Dwight Kravitz2,3
1National Institutes of Health.
Journal of Cognitive Neuroscience
|May 31, 2024
Summary
The "what" and "where/how" visual pathways are now understood as interconnected heterarchies, not separate serial routes. This neuroanatomy framework evolution highlights flexible visual processing in the brain.
Area of Science:
- Neuroscience
- Visual System Research
- Cognitive Science
Background:
- The two-cortical visual pathways framework (dorsal and ventral) has guided vision research for over 40 years.
- This framework historically conceptualized distinct 'what' (ventral) and 'where/how' (dorsal) pathways from primary visual cortex.
- It grounded physiological responses and behavior in neuroanatomy, providing a crucial model for visual system understanding.
Purpose of the Study:
- To historically review the evolution of the two cortical visual pathways framework.
- To discuss key insights and overlooked evidence regarding visual processing.
- To present current understanding of visual pathways beyond a simple bifurcation model.
Main Methods:
- Historical analysis of theoretical and empirical studies on the visual system.
- Review of neuroanatomical and physiological evidence.
- Synthesis of current research challenging traditional pathway models.
Main Results:
- Evidence suggests visual processing involves two highly recurrent heterarchies, not independent serial pathways.
- These heterarchies feature heterogeneous connections to cortical and subcortical regions.
- The revised model supports flexible and varied behavioral support, moving beyond strict 'what' vs. 'where/how' separation.
Conclusions:
- The traditional two-pathway model's simplifying assumptions are increasingly challenged by empirical evidence.
- Current understanding favors interconnected, recurrent networks over strictly segregated pathways.
- Further research into human neuroanatomy is critical for a comprehensive understanding of visual processing.
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