Visual Development and Object Recognition
120 Specialized Visual Areas
Learning Objectives
Know what the dorsal and ventral pathways in the visual cortex are.
Know what the anatomical and functional differences are between the dorsal and ventral pathways.
Be able to list some brain regions in both pathways.
Complex computations relating to vision, those that eventually allow you to have a visual experience of the world, all happen in the cortex. The first stop in the cortex is at the primary visual cortex (also known as V1). Here, the “reconstruction” process begins in earnest—based on the contrast information arriving from the eyes, neurons will start computing information about color and simple lines, detecting various orientations and thicknesses. Small-scale motion signals are also computed (Hubel & Wiesel, 1962). The computation of motion and aspects like color are what give rise to the ventral and dorsal pathways of vision.
Visual-recognition areas are located along the ventral pathway of the brain and terminate around the temporal lobe (the What pathway). Information that is funneled through this pathway is focused on identifying what a specific object is. Identification relies on multiple brain structures. We’ll name just a few here:
- The fusiform face area specializes in identifying objects for which fine discriminations are required, like faces. A later section of this book is dedicated to FFA.
- Extrastriate and fusiform body areas help us recognize and anticipate the motions of human bodies (Amoruso et al, 2011).
- Superior temporal sulcus houses many specialized regions related to language and social processing, with a posterior section that is specialized for the recognition of biological motion (Herrington et al, 2011).
- There is even a brain region specialized in letter and word processing called with visual word form area.
Brain regions along the dorsal pathway, near the parietal lobe (Fig. 11.4.1), (also referred to as Where-and-How pathway) compute information about self-motion and object-motion, allowing you to interact with objects, navigate the environment, and avoid obstacles (Goodale and Milner, 1992).
Exercises
- Which answer fills in the blanks the best? The _______ pathway (also known as the Where-and-How pathway) will compute information about self- and object- motion to allow you to navigate and interact with the environment while the _________ pathway (also known as the What pathway) will compute information to identify what a specific object is.
A. Ventral; Dorsal
B. MT; MST
C. Dorsal; Ventral
D. MST; MT
Answer: C
References
Herrington, J. D., Nymberg, C. Schultz, R. T. (2011). Biological motion task performance predicts superior temporal sulcus activity. Brain and Cognition 77(3):372-381. doi.org/10.1016/j.bandc.2011.09.001.
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NOBA, Vision
Provided by: University of Illinois at Urbana-Champaign
URL: https://nobaproject.com/modules/vision
License: CC BY-NC-SA 4.0
Adapted by: John Taylor