TY - JOUR
T1 - Activation of the primary visual cortex by Braille reading in blind subjects
AU - Sadato, Norihiro
AU - Pascual-Leone, Alvaro
AU - Grafman, Jordan
AU - Ibañez, Vicente
AU - Deiber, Marie Pierre
AU - Dold, George
AU - Hallett, Mark
PY - 1996/4/11
Y1 - 1996/4/11
N2 - Primary visual cortex receives visual input from the eyes through the lateral geniculate nuclei, but is not known to receive input from other sensory modalities. Its level of activity, both at rest and during auditory or tactile tasks, is higher in blind subjects than in normal controls, suggesting that it can subserve non-visual functions; however, a direct effect of non-visual tasks on activation has not been demonstrated. To determine whether the visual cortex receives input from the somatosensory system, we used positron emission tomography (PET) to measure activation during tactile discrimination tasks in normal subjects and in Braille readers blinded in early life. Blind subjects showed activation of primary and secondary visual cortical areas during tactile tasks, whereas normal controls showed deactivation. A simple tactile stimulus that did not require discrimination produced no activation of visual areas in either group. Thus, in blind subjects, cortical areas normally reserved for vision may be activated by other sensory modalities.
AB - Primary visual cortex receives visual input from the eyes through the lateral geniculate nuclei, but is not known to receive input from other sensory modalities. Its level of activity, both at rest and during auditory or tactile tasks, is higher in blind subjects than in normal controls, suggesting that it can subserve non-visual functions; however, a direct effect of non-visual tasks on activation has not been demonstrated. To determine whether the visual cortex receives input from the somatosensory system, we used positron emission tomography (PET) to measure activation during tactile discrimination tasks in normal subjects and in Braille readers blinded in early life. Blind subjects showed activation of primary and secondary visual cortical areas during tactile tasks, whereas normal controls showed deactivation. A simple tactile stimulus that did not require discrimination produced no activation of visual areas in either group. Thus, in blind subjects, cortical areas normally reserved for vision may be activated by other sensory modalities.
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U2 - 10.1038/380526a0
DO - 10.1038/380526a0
M3 - Article
C2 - 8606771
AN - SCOPUS:0029914588
SN - 0028-0836
VL - 380
SP - 526
EP - 528
JO - Nature
JF - Nature
IS - 6574
ER -