Georgetown University Medical Center, Washington DC 20057, USA.
Neuroimage. 2012 Mar;60(1):661-72. doi: 10.1016/j.neuroimage.2011.12.031. Epub 2011 Dec 22.
Experience-dependent plasticity in deaf participants has been shown in a variety of studies focused on either the dorsal or ventral aspects of the visual system, but both systems have never been investigated in concert. Using functional magnetic resonance imaging (fMRI), we investigated functional plasticity for spatial processing (a dorsal visual pathway function) and for object processing (a ventral visual pathway function) concurrently, in the context of differing sensory (auditory deprivation) and language (use of a signed language) experience. During scanning, deaf native users of American Sign Language (ASL), hearing native ASL users, and hearing participants without ASL experience attended to either the spatial arrangement of frames containing objects or the identity of the objects themselves. These two tasks revealed the expected dorsal/ventral dichotomy for spatial versus object processing in all groups. In addition, the object identity matching task contained both face and house stimuli, allowing us to examine category-selectivity in the ventral pathway in all three participant groups. When contrasting the groups we found that deaf signers differed from the two hearing groups in dorsal pathway parietal regions involved in spatial cognition, suggesting sensory experience-driven plasticity. Group differences in the object processing system indicated that responses in the face-selective right lateral fusiform gyrus and anterior superior temporal cortex were sensitive to a combination of altered sensory and language experience, whereas responses in the amygdala were more closely tied to sensory experience. By selectively engaging the dorsal and ventral visual pathways within participants in groups with different sensory and language experiences, we have demonstrated that these experiences affect the function of both of these systems, and that certain changes are more closely tied to sensory experience, while others are driven by the combination of sensory and language experience.
在各种专注于视觉系统背侧或腹侧方面的研究中，都已经证明了聋人参与者的经验依赖性可塑性，但这两个系统从未同时进行过研究。我们使用功能磁共振成像 (fMRI)，同时研究了空间处理（背侧视觉通路功能）和物体处理（腹侧视觉通路功能）的功能可塑性，这两种功能的研究背景是不同的感官（听觉剥夺）和语言（使用手语）经验。在扫描过程中，美国手语（ASL）的聋人母语使用者、听力母语 ASL 用户和没有 ASL 经验的听力参与者分别关注包含物体的框架的空间排列或物体本身的身份。这两个任务揭示了所有组中预期的空间与物体处理之间的背侧/腹侧二分法。此外，物体身份匹配任务包含面部和房屋刺激，使我们能够在所有三个参与者群体中检查腹侧通路中的类别选择性。当对比这些组时，我们发现聋人使用者与两个听力组在涉及空间认知的背侧通路顶叶区域存在差异，表明感官经验驱动的可塑性。物体处理系统的组间差异表明，在右侧外侧梭状回和前上颞叶皮层的面部选择性区域的反应对改变的感官和语言经验的组合敏感，而杏仁核的反应则与感官经验更为密切相关。通过选择性地在具有不同感官和语言经验的参与者中参与背侧和腹侧视觉通路，我们证明了这些经验会影响这两个系统的功能，并且某些变化与感官经验更为密切相关，而其他变化则是由感官和语言经验的组合驱动的。
