负性BOLD可区分视觉意象与知觉。

Negative BOLD differentiates visual imagery and perception.

作者信息

Amedi Amir, Malach Rafael, Pascual-Leone Alvaro

机构信息

Center for Noninvasive Brain Stimulation, Department of Neurology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts 02115, USA.

出版信息

Neuron. 2005 Dec 8;48(5):859-72. doi: 10.1016/j.neuron.2005.10.032.

DOI:10.1016/j.neuron.2005.10.032

PMID:16337922

Abstract

Recent studies emphasize the overlap between the neural substrates of visual perception and visual imagery. However, the subjective experiences of imagining and seeing are clearly different. Here we demonstrate that deactivation of auditory cortex (and to some extent of somatosensory and subcortical visual structures) as measured by BOLD functional magnetic resonance imaging unequivocally differentiates visual imagery from visual perception. During visual imagery, auditory cortex deactivation negatively correlates with activation in visual cortex and with the score in the subjective vividness of visual imagery questionnaire (VVIQ). Perception of the world requires the merging of multisensory information so that, during seeing, information from other sensory systems modifies visual cortical activity and shapes experience. We suggest that pure visual imagery corresponds to the isolated activation of visual cortical areas with concurrent deactivation of "irrelevant" sensory processing that could disrupt the image created by our "mind's eye."

摘要

近期研究强调了视觉感知和视觉意象的神经基质之间的重叠。然而，想象和看见的主观体验明显不同。在此我们证明，通过血氧水平依赖性功能磁共振成像测量，听觉皮层（以及在一定程度上体感和皮层下视觉结构）的失活明确区分了视觉意象和视觉感知。在视觉意象过程中，听觉皮层失活与视觉皮层的激活以及视觉意象问卷（VVIQ）主观生动性得分呈负相关。对世界的感知需要多感官信息的融合，因此在看见过程中，来自其他感觉系统的信息会改变视觉皮层活动并塑造体验。我们认为，纯粹的视觉意象对应于视觉皮层区域的孤立激活，同时“无关”感觉处理失活，而这种失活可能会干扰我们“心灵之眼”所创造的图像。