Center for Mind/Brain Sciences, University of Trento, 38068 Rovereto (Trentino), Italy.
J Neurosci. 2012 Nov 7;32(45):15728-36. doi: 10.1523/JNEUROSCI.1953-12.2012.
Interaction with everyday objects requires the representation of conceptual object properties, such as where and how an object is used. What are the neural mechanisms that support this knowledge? While research on semantic dementia has provided evidence for a critical role of the anterior temporal lobes (ATLs) in object knowledge, fMRI studies using univariate analysis have primarily implicated regions outside the ATL. In the present human fMRI study we used multivoxel pattern analysis to test whether activity patterns in ATLs carry information about conceptual object properties. Participants viewed objects that differed on two dimensions: where the object is typically found (in the kitchen or the garage) and how the object is commonly used (with a rotate or a squeeze movement). Anatomical region-of-interest analyses covering the ventral visual stream revealed that information about the location and action dimensions increased from posterior to anterior ventral temporal cortex, peaking in the temporal pole. Whole-brain multivoxel searchlight analysis confirmed these results, revealing highly significant and regionally specific information about the location and action dimensions in the anterior temporal lobes bilaterally. In contrast to conceptual object properties, perceptual and low-level visual properties of the objects were reflected in activity patterns in posterior lateral occipitotemporal cortex and occipital cortex, respectively. These results provide fMRI evidence that object representations in the anterior temporal lobes are abstracted away from perceptual properties, categorizing objects in semantically meaningful groups to support conceptual object knowledge.
与日常物体交互需要表示概念物体属性,例如物体的位置和使用方式。支持这种知识的神经机制是什么?虽然语义痴呆症的研究为前颞叶(ATL)在物体知识中的关键作用提供了证据,但使用单变量分析的 fMRI 研究主要涉及 ATL 以外的区域。在本项人类 fMRI 研究中,我们使用多体素模式分析来测试 ATLs 中的活动模式是否携带有关概念物体属性的信息。参与者观看了在两个维度上存在差异的物体:物体通常在哪里(在厨房或车库)和如何常见地使用(旋转或挤压运动)。涵盖腹侧视觉流的解剖 ROI 分析表明,关于位置和动作维度的信息从前向后增加到腹侧颞叶皮质,在颞极达到峰值。全脑多体素搜索灯分析证实了这些结果,揭示了双侧前颞叶中关于位置和动作维度的高度显著和区域特异性信息。与概念物体属性相反,物体的感知和低水平视觉属性分别反映在后部外侧枕颞皮质和枕叶皮质的活动模式中。这些结果提供了 fMRI 证据,表明前颞叶中的物体表示与感知属性分离,将物体分类为语义上有意义的组,以支持概念物体知识。