Reilly Jamie, Garcia Amanda, Binney Richard J
Eleanor M. Saffran Center for Cognitive Neuroscience, Temple University, Philadelphia, PA, USA; Department of Communication Sciences and Disorders, Temple University, Philadelphia, PA, USA.
Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA.
Brain Lang. 2016 Aug;159:45-59. doi: 10.1016/j.bandl.2016.05.006. Epub 2016 Jun 9.
Much remains to be learned about the neural architecture underlying word meaning. Fully distributed models of semantic memory predict that the sound of a barking dog will conjointly engage a network of distributed sensorimotor spokes. An alternative framework holds that modality-specific features additionally converge within transmodal hubs. Participants underwent functional MRI while covertly naming familiar objects versus newly learned novel objects from only one of their constituent semantic features (visual form, characteristic sound, or point-light motion representation). Relative to the novel object baseline, familiar concepts elicited greater activation within association regions specific to the presentation modality. Furthermore, visual form elicited activation within high-level auditory association cortex. Conversely, environmental sounds elicited activation in regions proximal to visual association cortex. Both conditions commonly engaged a putative hub region within lateral anterior temporal cortex. These results support hybrid semantic models in which local hubs and distributed spokes are dually engaged in service of semantic memory.
关于构成词义基础的神经结构,仍有许多有待了解之处。语义记忆的完全分布式模型预测,一只吠叫的狗的声音会联合激活一个分布式感觉运动辐条网络。另一种框架认为,特定模态的特征还会在跨模态枢纽内汇聚。参与者在进行功能磁共振成像时,会暗中说出熟悉的物体,以及仅从其一个构成语义特征(视觉形式、特征声音或点光运动表示)中学习到的新的新奇物体。相对于新奇物体基线,熟悉的概念在特定于呈现模态的联合区域内引发了更大的激活。此外,视觉形式在高级听觉联合皮层内引发了激活。相反,环境声音在视觉联合皮层附近的区域引发了激活。这两种情况通常都会激活外侧前颞叶皮层内的一个假定枢纽区域。这些结果支持了混合语义模型,其中局部枢纽和分布式辐条双重参与为语义记忆服务。