Sakai K, Watanabe E, Onodera Y, Uchida I, Kato H, Yamamoto E, Koizumi H, Miyashita Y
Department of Physiology, School of Medicine, University of Tokyo, Japan.
Proc Biol Sci. 1995 Jul 22;261(1360):89-98. doi: 10.1098/rspb.1995.0121.
Clinical studies of cerebral achromatopsia have suggested a colour centre in the human fusiform gyrus. By using functional magnetic resonance imaging, we examined whether the fusiform gyrus shows activity correlated with the perception of colour. We tested three stimulus conditions in which the subject maintained fixation: (i) a circular array of six coloured circles; (ii) the same as (i) except that each circle is equiluminant grey with its colour counterpart; and (iii) the same as (i) plus a clockwise shift of circles to neighbouring positions every 1 s. After termination of the stimulus, the subject perceived an after-image of circles with complementary colours in (i), but not in (iii). In condition (i), we found a focal signal increase in the posterior part of the fusiform gyrus. In condition (ii), the activation in the same locus during the stimulation period was weaker than that in (i). In condition (iii), the signal intensity after termination of the stimulus was weaker than that in (i). The colour effect and after-effect on activation of the fusiform gyrus observed here suggest its critical role in human colour perception.
大脑色盲症的临床研究表明人类梭状回中存在一个颜色中枢。通过使用功能磁共振成像，我们研究了梭状回是否表现出与颜色感知相关的活动。我们测试了三种刺激条件，受试者在这些条件下保持注视：（i）六个彩色圆圈组成的圆形阵列；（ii）与（i）相同，但每个圆圈与其颜色对应物具有相同的亮度，均为灰色；（iii）与（i）相同，外加圆圈每隔1秒顺时针移动到相邻位置。刺激结束后，受试者在（i）条件下能感知到具有互补颜色的圆圈后像，但在（iii）条件下则不能。在条件（i）中，我们发现梭状回后部有一个局部信号增强。在条件（ii）中，刺激期间同一位置的激活比（i）中的弱。在条件（iii）中，刺激结束后的信号强度比（i）中的弱。此处观察到的颜色效应和对梭状回激活的后效应表明其在人类颜色感知中起关键作用。
