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Updated: Jul 11, 2026
08:49
Visualization of Cortical Modules in Flattened Mammalian Cortices
Published on: January 22, 2018
Defining the cortical visual systems: "what", "where", and "how"
1Department of Psychology, University of Utah, 380 S. 1530 E., Rm 502, Salt Lake City, UT 84112-0251, USA. sarah.creem@psych.utah.edu
Acta Psychologica
|June 5, 2001
Summary
The brain
Area of Science:
- Neuroscience
- Visual Perception
- Cognitive Science
Background:
- The visual system comprises distinct pathways for object and spatial processing.
- Historically, ventral ('what') and dorsal ('where') streams were defined.
- Recent models propose dorsal stream for action-oriented ('how') processing.
Purpose of the Study:
- To review research defining the roles of ventral and dorsal visual streams.
- To explore functional and structural organization within these streams.
- To reconcile 'where' and 'how' system models.
Main Methods:
- Review of psychophysical studies.
- Analysis of neurophysiological data.
- Examination of neuropsychological and neuroimaging findings.
Main Results:
- Ventral stream processes object identity ('what').
- Dorsal stream transforms visual information for action ('how').
- Evidence supports distinct, yet integrated, functional roles.
Conclusions:
- The posterior parietal lobe may host both 'where' and 'how' systems.
- Functional specialization and integration are key to visual processing.
- A unified model reconciling different stream definitions is proposed.
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