Sadato Norihiro, Okada Tomohisa, Kubota Kiyokazu, Yonekura Yoshiharu
National Institute for Physiological Sciences, 38 Nishigonaka, Myodaiji, Okazaki, 444-8585, Japan.
Neurosci Lett. 2004 Apr 8;359(1-2):49-52. doi: 10.1016/j.neulet.2004.02.005.
The occipital cortex of blind subjects is known to be activated during tactile discrimination tasks such as Braille reading. To investigate whether this is due to long-term learning of Braille or to sensory deafferentation, we used fMRI to study tactile discrimination tasks in subjects who had recently lost their sight and never learned Braille. The occipital cortex of the blind subjects without Braille training was activated during the tactile discrimination task, whereas that of control sighted subjects was not. This finding suggests that the activation of the visual cortex of the blind during performance of a tactile discrimination task may be due to sensory deafferentation, wherein a competitive imbalance favors the tactile over the visual modality.
众所周知，盲人在进行诸如盲文阅读等触觉辨别任务时，枕叶皮质会被激活。为了研究这是由于长期学习盲文还是由于感觉传入缺失，我们使用功能磁共振成像（fMRI）来研究近期失明且从未学习过盲文的受试者的触觉辨别任务。在触觉辨别任务中，未接受盲文训练的盲人受试者的枕叶皮质被激活，而有视力的对照受试者的枕叶皮质未被激活。这一发现表明，盲人在执行触觉辨别任务时视觉皮质的激活可能是由于感觉传入缺失，即竞争性失衡使触觉模式优于视觉模式。
