ffytche Dominic H, Pins Delphine
Institute of Psychiatry PO 70, De Crespigny Park, London SE5 8AF, UK.
Neuroreport. 2003 Nov 14;14(16):2011-4. doi: 10.1097/00001756-200311140-00001.
Some visual neurons code what we see, their defining characteristic being a response profile which mirrors conscious percepts rather than veridical sensory attributes. One issue yet to be resolved is whether, within a given cortical area, conscious visual perception relates to diffuse activity across the entire population of such cells or focal activity within the sub-population mapping the location of the perceived stimulus. Here we investigate the issue in the human brain with fMRI, using a threshold stimulation technique to dissociate perceptual from non-perceptual activity. Our results point to a retinotopic organisation of perceptual activity in early visual areas, with independent perceptual activations for different regions of visual space.
一些视觉神经元对我们所看到的内容进行编码,其决定性特征是一种反应模式,该模式反映的是有意识的感知,而非真实的感官属性。一个尚未解决的问题是,在给定的皮层区域内,有意识的视觉感知是与这类细胞的整个群体中的弥散活动相关,还是与映射所感知刺激位置的亚群体中的局部活动相关。在这里,我们使用功能磁共振成像(fMRI)在人类大脑中研究这个问题,采用阈值刺激技术来区分感知活动和非感知活动。我们的结果表明,早期视觉区域中存在感知活动的视网膜拓扑组织,不同视觉空间区域有独立的感知激活。