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Updated: Jun 24, 2026
07:11
Functional Magnetic Resonance Imaging (fMRI) of the Visual Cortex with Wide-View Retinotopic Stimulation
Published on: December 8, 2023
Retinotopically specific reorganization of visual cortex for tactile pattern recognition.
Sing-Hang Cheung1, Fang Fang, Sheng He
1Department of Psychology, The University of Hong Kong, Hong Kong, China. singhang@hku.hk
Current Biology : CB
|April 14, 2009
Summary
Tactile Braille reading reorganizes the visual cortex, with touch activating central visual areas and vision activating peripheral areas in a visually impaired individual. This retinotopic specificity suggests efficient neural resource redistribution.
Area of Science:
- Neuroscience
- Cognitive Science
- Neuroimaging
Background:
- Previous studies show tactile tasks activate the visual cortex in blind and sighted individuals.
- The influence of retinotopic organization on this crossmodal reorganization remains unclear.
Purpose of the Study:
- To investigate whether retinotopic organization influences crossmodal visual cortex reorganization.
- To examine tactile and visual processing in the visual cortex of a visually impaired individual with unique reading abilities.
Main Methods:
- Functional magnetic resonance imaging (fMRI) was used to study a visually impaired adult (S).
- S could read both print visually and Braille tactilely.
- Control experiments ruled out visual imagery as a cause for activation patterns.
Main Results:
- In early visual areas, tactile Braille processing activated the foveal representation, while visual print processing activated the peripheral representation.
- High-level visual areas (shape- and object-selective) were activated by both visual and tactile stimuli.
- Activation patterns were not attributable to visual imagery.
Conclusions:
- Crossmodal reorganization in the visual cortex is retinotopically specific.
- This suggests an efficient redistribution of neural resources in the visual cortex.
- The findings provide insights into the plasticity of the human brain.
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