Quiroga R Quian, Mukamel R, Isham E A, Malach R, Fried I
Department of Engineering, University of Leicester, Leicester LE1 7RH, United Kingdom.
Proc Natl Acad Sci U S A. 2008 Mar 4;105(9):3599-604. doi: 10.1073/pnas.0707043105. Epub 2008 Feb 25.
We studied the responses of single neurons in the human medial temporal lobe while subjects viewed familiar faces, animals, and landmarks. By progressively shortening the duration of stimulus presentation, coupled with backward masking, we show two striking properties of these neurons. (i) Their responses are not statistically different for the 33-ms, 66-ms, and 132-ms stimulus durations, and only for the 264-ms presentations there is a significantly higher firing. (ii) These responses follow conscious perception, as indicated by the subjects' recognition report. Remarkably, when recognized, a single snapshot as brief as 33 ms was sufficient to trigger strong single-unit responses far outlasting stimulus presentation. These results suggest that neurons in the medial temporal lobe can reflect conscious recognition by "all-or-none" responses.
我们研究了人类内侧颞叶单个神经元的反应，实验中让受试者观看熟悉的面孔、动物和地标。通过逐步缩短刺激呈现的持续时间，并结合逆向掩蔽，我们发现了这些神经元的两个显著特性。（i）对于33毫秒、66毫秒和132毫秒的刺激持续时间，它们的反应在统计学上没有差异，只有在264毫秒的呈现时才有显著更高的放电率。（ii）如受试者的识别报告所示，这些反应跟随有意识的感知。值得注意的是，当被识别时，一张短至33毫秒的单张快照就足以触发强烈的单神经元反应，且反应持续时间远远超过刺激呈现时间。这些结果表明，内侧颞叶中的神经元可以通过“全或无”反应来反映有意识的识别。
