Amedi Amir, Raz Noa, Pianka Pazit, Malach Rafael, Zohary Ehud
Neurobiology Department, Life Science Institute, Hebrew University, Jerusalem 91904, Israel.
Nat Neurosci. 2003 Jul;6(7):758-66. doi: 10.1038/nn1072.
The visual cortex may be more modifiable than previously considered. Using functional magnetic resonance imaging (fMRI) in ten congenitally blind human participants, we found robust occipital activation during a verbal-memory task (in the absence of any sensory input), as well as during verb generation and Braille reading. We also found evidence for reorganization and specialization of the occipital cortex, along the anterior-posterior axis. Whereas anterior regions showed preference for Braille, posterior regions (including V1) showed preference for verbal-memory and verb generation (which both require memory of verbal material). No such occipital activation was found in sighted subjects. This difference between the groups was mirrored by superior performance of the blind in various verbal-memory tasks. Moreover, the magnitude of V1 activation during the verbal-memory condition was highly correlated with the blind individual's abilities in a variety of verbal-memory tests, suggesting that the additional occipital activation may have a functional role.
视觉皮层的可修改性可能比之前认为的更高。在十名先天性盲人参与者中使用功能磁共振成像（fMRI），我们发现在言语记忆任务期间（在没有任何感觉输入的情况下）以及在动词生成和盲文阅读期间，枕叶有强烈激活。我们还发现了枕叶皮质沿前后轴重组和特化的证据。前部区域对盲文表现出偏好，而后部区域（包括V1）对言语记忆和动词生成（两者都需要言语材料记忆）表现出偏好。在有视力的受试者中未发现这种枕叶激活。两组之间的这种差异反映在盲人在各种言语记忆任务中的优越表现上。此外，言语记忆条件下V1激活的程度与盲人个体在各种言语记忆测试中的能力高度相关，这表明额外的枕叶激活可能具有功能作用。
