MEG signal dynamics of chromatic motion mechanism

在本研究项目中，我使用脑磁图系统对心理物理学和脑功能成像中的彩色运动机制进行了研究。在心理学实验中，我测试了二阶彩色运动与二阶非彩色运动的整合，以阐明运动机制的最后一个皮质阶段可以处理彩色信息来产生彩色运动信号，或者将来自色彩中心的彩色运动信号(可能是V4)与非彩色运动信号进行整合。这一心理物理学的结果表明，最终阶段可以将二阶彩色和非彩色运动信号与时频域窄调谐的运动信号整合在一起，产生单一的相干运动感知。我还进行了心理学实验，研究了S视锥对运动机制的贡献。结果表明，S视锥细胞通过两种不同的途径参与运动：一种是通过色度通路的非线性运动机制，另一种是通过亮度通路的线性运动机制；脑磁图结果显示，信号的第一个峰值出现在视觉刺激开始后的100毫秒。这与常规脑磁图实验的结果是一致的。本研究项目可以在多个方面实现对颜色运动机制的详细了解。然而，它并不是彩色运动机构的全部图形。因此，有必要对后期相关的脑磁图信号进行分析，以找出整个变色运动的机制。

In this research project, I investigated chromatic motion mechanism in psychophysics and functional brain imaging with the use of MEG (MagnetoEncephaloGram) system.In the psychological experiments, I tested how second-order chromatic motion was integrated with second-order achromatic motion to clarify that the final cortical stage for motion mechanism can deal with chromatic information to produce chromatic motion signal or integrate chromatic motion signal coming from color center, probably V4, with achromatic motion signal. Results in this psychophysics indicate that the final stage can integrate second-order chromatic and achromatic motion signal with the narrow tuned in temporal frequency domain and produce a single coherent motion perception. I also carried out psychological experiment in which I investigated how S-cones contribute to motion mechanism. The results show that S-cones contribute to motion via two different pathways : a non-linear motion mechanism via a chromatic pathway and a linear motion mechanism via a luminance pathway.Results in MEG shows that the first peak of the signal occurs at 100 msec from onset of the visual stimuli. This is consistent with the results of conventional MEG experiments.This research project could achieve to find the detail of the chromatic motion mechanism in many of aspects. However, it is not the whole figure of the chromatic motion mechanism. It is therefore necessary to analyze MEG signals related on later stage in order to find the whole chromatic motion mechanism.