Functional relevance of cross-modal plasticity in blind humans

@article{Cohen1997FunctionalRO,
  title={Functional relevance of cross-modal plasticity in blind humans},
  author={Leonardo G. Cohen and Pablo A. Celnik and {\'A}lvaro Pascual-Leone and Brian N Corwell and Lala Faiz and James M. Dambrosia and Manabu Honda and Norihiro Sadato and Christian Gerloff and M. Dolores Catala´ and Mark Hallett},
  journal={Nature},
  year={1997},
  volume={389},
  pages={180-183}
}
Functional imaging studies of people who were blind from an early age have revealed that their primary visual cortex can be activated by Braille reading and other tactile discrimination tasks. Other studies have also shown that visual cortical areas can be activated by somatosensory input in blind subjects but not those with sight. The significance of this cross-modal plasticity is unclear, however, as it is not known whether the visual cortex can process somatosensory information in a… Expand
Critical Period for Cross-Modal Plasticity in Blind Humans: A Functional MRI Study
The primary visual cortex (V1) in congenitally blind humans has been shown to be involved in tactile discrimination tasks, indicating that there is a shift in function of this area of cortex, but theExpand
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TLDR
Recurrent transcranial magnetic stimulation is used to probe the connection between primary somatosensory cortex (S1) and early visual cortex (V1 and neighboring areas), combining rTMS with positron emission tomography (PET). Expand
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TMS of the occipital cortex induces tactile sensations in the fingers of blind Braille readers
TLDR
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TLDR
While visual cortical areas are clearly more involved in tactile microspatial processing in the blind than in the sighted, it still remains unclear how to reconcile these tactile processes with the growing literature implicating visual cortical activity in a wide range of cognitive tasks in theblind, including those involving language. Expand
Regions of visual cortex responding to tactile stimulation in an individual with longstanding low vision are not causally involved in tactile processing performance
TLDR
The data suggest that tactile responses in S’s foveal representation reflect unmasking of latent connections between visual and somatosensory cortices and not behaviourally relevant cross-modal plasticity, which is possible that the absence of complete visual loss in S has limited the degree of causally impactful cross- modal reorganisation. Expand
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TLDR
Recent findings from animal studies as well as from behavioural and functional brain imaging studies in sighted and blind individuals that address questions about how consciousness develops in the absence of vision are discussed. Expand
Rapid and Reversible Recruitment of Early Visual Cortex for Touch
TLDR
The findings suggest that sudden and complete visual deprivation in normally sighted individuals can lead to profound, but rapidly reversible, neuroplastic changes by which the occipital cortex becomes engaged in processing of non-visual information. Expand
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