Baird Benjamin, Cieslak Matthew, Smallwood Jonathan, Grafton Scott T, Schooler Jonathan W
University of California, Santa Barbara.
J Cogn Neurosci. 2015 Mar;27(3):440-52. doi: 10.1162/jocn_a_00741. Epub 2014 Oct 14.
The neural mechanisms that mediate metacognitive ability (the capacity to accurately reflect on one's own cognition and experience) remain poorly understood. An important question is whether metacognitive capacity is a domain-general skill supported by a core neuroanatomical substrate or whether regionally specific neural structures underlie accurate reflection in different cognitive domains. Providing preliminary support for the latter possibility, recent findings have shown that individual differences in metacognitive ability in the domains of memory and perception are related to variation in distinct gray matter volume and resting-state functional connectivity. The current investigation sought to build on these findings by evaluating how metacognitive ability in these domains is related to variation in white matter microstructure. We quantified metacognitive ability across memory and perception domains and used diffusion spectrum imaging to examine the relation between high-resolution measurements of white matter microstructure and individual differences in metacognitive accuracy in each domain. We found that metacognitive accuracy for perceptual decisions and memory were uncorrelated across individuals and that metacognitive accuracy in each domain was related to variation in white matter microstructure in distinct brain areas. Metacognitive accuracy for perceptual decisions was associated with increased diffusion anisotropy in white matter underlying the ACC, whereas metacognitive accuracy for memory retrieval was associated with increased diffusion anisotropy in the white matter extending into the inferior parietal lobule. Together, these results extend previous findings linking metacognitive ability in the domains of perception and memory to variation in distinct brain structures and connections.
介导元认知能力（准确反思自身认知和经验的能力）的神经机制仍未得到充分理解。一个重要问题是，元认知能力是由核心神经解剖学基质支持的领域通用技能，还是不同认知领域中准确反思背后存在区域特异性神经结构。最近的研究结果为后一种可能性提供了初步支持，表明记忆和感知领域中元认知能力的个体差异与不同灰质体积和静息态功能连接的变化有关。当前的研究旨在基于这些发现，评估这些领域中的元认知能力如何与白质微观结构的变化相关。我们量化了记忆和感知领域的元认知能力，并使用扩散光谱成像来检查白质微观结构的高分辨率测量与每个领域中元认知准确性的个体差异之间的关系。我们发现，个体之间感知决策和记忆的元认知准确性不相关，并且每个领域的元认知准确性与不同脑区白质微观结构的变化有关。感知决策的元认知准确性与前扣带回下方白质中扩散各向异性的增加有关，而记忆检索的元认知准确性与延伸至顶下小叶的白质中扩散各向异性的增加有关。总之，这些结果扩展了先前的研究发现，即将感知和记忆领域中的元认知能力与不同脑结构和连接的变化联系起来。
