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The blind get a taste of vision

  • Maurice Ptito
  • Daniel-Robert Chebat
  • Ron Kupers

Abstract

In sensory substitution a given sensory modality acquires the functional properties of a missing one. This phenomenon is due to a reorganization of the sensory systems that are deprived of their normal input through a process called cross-modal plasticity [1]. ‘Rewiring’ studies carried out on ferrets [2] and hamsters [3] provided strong support for these phenomena. For example, lesions of central retinal targets induce the formation of new and permanent retinofugal projections into non-visual thalamic sites such as the auditory nucleus [3]. Single neurons in the auditory cortex of these rewired animals respond to visual stimuli and some of them respond equally well to auditory as to visual stimuli. Moreover, those cells that respond to visual stimuli show properties (e.g., orientation selectivity, motion and direction sensitivity) similar to those encountered in the visual cortex of normal hamsters.

Keywords

Transcranial Magnetic Stimulation Visual Cortex Haptic Device Dorsal Stream Ventral Stream 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Selected readings

  1. Merabet LB, Rizzo JF, Amedi A, Somers DC, Pascual-Leone A (2005) What blindness can tell us about seeing again: merging neuroplasticity and neuroprostheses. Nat Rev Neurosci 6: 71–77PubMedCrossRefGoogle Scholar
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Copyright information

© Birkhäuser Verlag 2008

Authors and Affiliations

  • Maurice Ptito
    • 1
  • Daniel-Robert Chebat
    • 2
  • Ron Kupers
    • 3
  1. 1.Ecole ďOptométrieUniversité de MontréalMontréalCanada
  2. 2.Department of PsychologyUniversité de MontréalMontréalCanada
  3. 3.Department of Surgical Pathophysiology and Positron Emission Tomography UnitRigshosptitaletCopenhagenDenmark

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