Online tracking of the contents of conscious perception using real-time fMRI
Online tracking of the contents of conscious perception using real-time fMRI
复制标题
使用实时功能磁共振成像在线跟踪意识感知的内容
作者：
C. Reichert;R. Fendrich;J. Bernarding;C. Tempelmann;H. Hinrichs;J. Rieger
知觉是一种基于对刺激输入可能原因的假设来解释和构建刺激输入的主动过程。我们使用实时功能磁共振成像(RtfMRI)来研究动态对象整合的一个特别强大的演示，在该演示中，相同的物理刺激间歇性地引起截然不同的有意识对象感知。在这项研究中，我们模拟了一个在狭缝后面移动的轮廓对象。利用这种显示，物理上相同的刺激可以引起完全不同的感知，这些感知要么与物理刺激(垂直移动的线段)密切对应，要么代表关于物理刺激的潜在原因的假设(部分被遮挡的水平移动的对象)。在后一种情况下，大脑必须根据输入序列构建一个对象。结合rtfMRI和机器学习技术，我们表明，从时间分辨的大胆活动中，在线确定受试者有意识感知的瞬时状态是可能的。此外，我们发现，与没有反馈呈现的相同刺激的先前fMRI记录相比，关于当前解码的感知的反馈提高了解码率。对训练有素的分类器的分析揭示了一个大脑网络，它区分意识感知的内容，以及代表物理刺激特性的早期感觉区域和高级大脑区域之间的拮抗相互作用。在综合物体感知过程中，早期感觉区域的大脑活动减少，而较高层次区域的大脑活动增加。我们的结论是，可以使用大胆的反应来以相对较高的时间分辨率可靠地跟踪意识视觉知觉的内容。我们认为，我们的方法也可以用来研究听觉对象形成的神经基础，并在预测编码理论的背景下讨论结果。
Perception is an active process that interprets and structures the stimulus input based on assumptions about its possible causes. We use real-time functional magnetic resonance imaging (rtfMRI) to investigate a particularly powerful demonstration of dynamic object integration in which the same physical stimulus intermittently elicits categorically different conscious object percepts. In this study, we simulated an outline object that is moving behind a narrow slit. With such displays, the physically identical stimulus can elicit categorically different percepts that either correspond closely to the physical stimulus (vertically moving line segments) or represent a hypothesis about the underlying cause of the physical stimulus (a horizontally moving object that is partly occluded). In the latter case, the brain must construct an object from the input sequence. Combining rtfMRI with machine learning techniques we show that it is possible to determine online the momentary state of a subject's conscious percept from time resolved BOLD-activity. In addition, we found that feedback about the currently decoded percept increased the decoding rates compared to prior fMRI recordings of the same stimulus without feedback presentation. The analysis of the trained classifier revealed a brain network that discriminates contents of conscious perception with antagonistic interactions between early sensory areas that represent physical stimulus properties and higher-tier brain areas. During integrated object percepts, brain activity decreases in early sensory areas and increases in higher-tier areas. We conclude that it is possible to use BOLD responses to reliably track the contents of conscious visual perception with a relatively high temporal resolution. We suggest that our approach can also be used to investigate the neural basis of auditory object formation and discuss the results in the context of predictive coding theory.
影响因子：
5.7
作者：
J. Rieger;C. Reichert;K. Gegenfurtner;T. Noesselt;C. Braun;H. Heinze;R. Kruse;H. Hinrichs
通讯作者：
J. Rieger;C. Reichert;K. Gegenfurtner;T. Noesselt;C. Braun;H. Heinze;R. Kruse;H. Hinrichs
影响因子：
24.8
作者：
Tong F;Pratte MS
通讯作者：
Pratte MS