Miyashita Y, Chang H S
Department of Physiology, Faculty of Medicine, University of Tokyo, Japan.
Nature. 1988 Jan 7;331(6151):68-70. doi: 10.1038/331068a0.
It has been proposed that visual-memory traces are located in the temporal lobes of the cerebral cortex, as electric stimulation of this area in humans results in recall of imagery. Lesions in this area also affect recognition of an object after a delay in both humans and monkeys, indicating a role in short-term memory of images. Single-unit recordings from the temporal cortex have shown that some neurons continue to fire when one of two or four colours are to be remembered temporarily. But neuronal responses selective to specific complex objects, including hands and faces, cease soon after the offset of stimulus presentation. These results led to the question of whether any of these neurons could serve the memory of complex objects. We report here a group of shape-selective neurons in an anterior ventral part of the temporal cortex of monkeys that exhibited sustained activity during the delay period of a visual short-term memory task. The activity was highly selective for the pictorial information to be memorized and was independent of the physical attributes such as size, orientation, colour or position of the object. These observations show that the delay activity represents the short-term memory of the categorized percept of a picture.
有人提出视觉记忆痕迹位于大脑皮层的颞叶，因为对人类该区域进行电刺激会引发图像回忆。该区域的损伤在人类和猴子身上也会影响延迟后对物体的识别，表明其在图像短期记忆中发挥作用。来自颞叶皮层的单神经元记录显示，当需要暂时记住两种或四种颜色中的一种时，一些神经元会持续放电。但是，对包括手和脸在内的特定复杂物体具有选择性的神经元反应在刺激呈现结束后很快就会停止。这些结果引发了一个问题，即这些神经元中是否有任何一个可以用于记忆复杂物体。我们在此报告，在猴子颞叶皮层前腹侧部分存在一组形状选择性神经元，它们在视觉短期记忆任务的延迟期表现出持续活动。这种活动对要记忆的图像信息具有高度选择性，并且与物体的大小、方向、颜色或位置等物理属性无关。这些观察结果表明，延迟活动代表了对图片分类感知的短期记忆。
