采用事件相关电位(ERPs)技术探索延迟匹配任务范式下面孔识别工作记忆的脑电位特征。实验以面孔图片为刺激,在校大学生被试完成靶匹配工作记忆任务。结果发现,被试识别靶面孔及分心物面孔时均在枕颞区两侧诱发N170,且靶与分心物的N170振幅在相同电极上都没有显著差异,在颞区两侧的P7和P8上差异显著;无论靶面孔还是分心物面孔,工作记忆的ERPs均产生了P300成分。在分别追踪新靶和熟悉靶的工作记忆任务条件下,靶与分心物的ERPs波形在250ms后出现分离,且靶刺激波幅均比分心物更正,新靶比熟悉靶更正。熟悉分心物与新分心物之间显示出250~650ms的前额区IH/新效应,在晚期的450~650ms时段,新工作记忆比旧工作记忆波幅更正。这些结果表明,面孔识别的N170效应可能反映的是面孔知觉的整体加工,且N170的右半球优势具体为颞区的右侧优势:先前的面孔学习会影响工作记忆期间大脑对面孔的识别反应。
As one of the most important skills in human's daily life, face recognition can help us to promote social interactions and adapt to the environment. Previous ERP studies showed that face recognition could induce N 170 (a negative potential peaking at about 170ms) over lateral occipito-temporal electrodes, some researchers argued that N 170 might reflect the early structural encoding process. It is widely recognized that N 170 possesses right hemisphere advantage, which suggests that the right hemisphere of brain is mainly responsible for structural encoding process. Searching for a specific face (the target) in the crowd and distinguishing it from other's faces (distractors) are related to working memory which refers to the limited resource system for temporary storage and information processing. Since it is an important function of working memory to intentionally hold an item in mind for current use, the relevant research on working memory is more than 30 years. But the brain potential features of human face recognition during working memory as well as the brain responses to matching faces affected by prior learning remain unclear. Therefore, this article employs event-related potentials (ERPs) technology to explore the essence of face recognition N170 effect and the brain potential features of face recognition during working memory. The influence of prior learning on tracking and discrimination processes is also examined, which depends on the working memory status of a face. The delayed match-to-sample task paradigm was used in this study with pictures of faces as stimuli. 16 college students (eight male and eight female, Mean age = 20.31 years) participated in the experiment and performed sample target match tasks during working memory, tracking targets (familiar and new targets) and excluding the distractors (familiar and new distractors). The ERP results revealed that NI70 was induced over lateral occipito-temporal electrodes when participants recognized the targets and dist