任务类型对面孔联合效应和特征效应的调节

The Conjunction Effect and Feature Effect in Faces Are Modulated by Task Type

采用特征-联合范式的研究发现,面孔再认阶段可记录到明显的联合效应和特征效应;然而,与再认同属情景记忆的另一任务(来源提取)条件的相应效应尚未报道,背景信息一致性对联合面孔和特征面孔提取的调节作用以及面孔不同特征对特征效应的影响也未考察。为澄清上述问题,本文采用特征-联合范式,并以位置为背景展开研究。实验含一个学习任务和两个测验任务(再认和来源提取)。结果显示,再认和来源提取阶段均记录到显著的联合效应和特征效应,且两类效应均在来源提取阶段更强;任务类型与位置背景一致性交互影响提取绩效;面孔外部特征和内部特征对特征效应的影响相似。表明联合效应和特征效应具有显著的任务类型敏感性,这些效应是联合面孔和特征面孔的熟悉性较强且对源面孔的回忆加工相对较弱的结果,且这两类面孔的提取为背景一致性所调节;任务类型对两类效应的调节与双重加工理论模型相吻合。

Previous research has suggested that faces can produce robust conjunction and feature effects at item recognition in the feature-conjunction paradigm. However, whether such two effects are affected when the task and contextual details are manipulated, has not been described yet. Also, the contribution of external facial features versus internal facial features to feature effect needs further exploration. Thus, the first goal of the present study was to investigate to what extent that the two effects were affected by task type（the two aspects of episodic memory, i.e., item recognition and source retrieval） for unfamiliar faces in the feature-conjunction paradigm. The second goal was to explore the interaction between the consistency of presentation location and task type. Third, we would study the possible difference between external facial features and internal facial features in the case of feature effect. Thirty-one subjects participated in this experiment. The formal stimuli were 720 headshots of unfamiliar individuals, half male and half female. In the study stage, subjects were asked to learn some unfamiliar faces that were either presented on the left side or on the right side of the screen. In the test stage, five types of faces were displayed, left or right： old faces, conjunction faces, old external feature faces, old internal feature faces, and totally new faces; and two types of tasks were randomly presented： the item recognition task during which subjects only had to make old/new judgments, and the source retrieval task which required an additional discrimination towards the location of old faces（i.e., subjects were instructed to differentiate the old faces that were displayed on the same location between study and test from the old faces on different locations and other faces）. The results showed that both tasks elicited robust conjunction effect and feature effect for faces, but they were larger in source retrieval task. The interaction between location consistency and task type was significant in terms of memory performance： At recognition, location consistency facilitated both effects, while no such facilitation was observed at source retrieval. The feature effect in old external faces was similar to that in internal feature faces. These results strongly demonstrate that both conjunction effect and feature effect are sensitive to task type, and suggests an important role of high familiarity compared with recollection in such two effects, consistent with the dual-process model. The discrimination of conjunction and feature faces is regulated by the interaction of whether the presentation location is consistent or not between study and test and task type. Additionally, old external facial features and old internal facial features play similar roles in the contribution to feature effect.