中国科学院心理研究所机构知识库

过去几乎所有的理论都假设知道感是一种由弱到强的主观感受的连续体。近期的脑成像研究结果提示：FOK与FOnK可能是由两种不同的认知与脑机制所实现的，由此结果罗劲等人提出了知道感的“双过程假说”。本研究试图从行为和脑电实验两方面来验证这一假说。

行为实验：以词对为材料、“回忆－FOK判断－再认”为实验程序，分别考察学习遍数、词对关联程度、线索词词频、非词对是否会对FOK和FOnK产生不同的影响。结果表明：如果换一种研究角度，把FOK和FOnK区分开来加以考虑的话，则过去通常认为能够影响知道感预测准确性的变量，对FOK和FOnK可能会造成不同的影响，甚至是相反的影响。学习遍数、词对关联程度、高频线索词提高FOK预测准确性并降低FOnK预测准确性；低频线索词、非词对降低FOK预测准确性并提高FOnK预测准确性，从而实现FOK与FOnK的双重分离。

脑电实验：首次使用事件相关电位（ERP, event-related-potential）研究FOK,借助ERP实时性的特点，探讨FOK和FOnK判断在时间和空间上的分离点。选用双字名词组成无关词对，程序同行为实验。结果提示相对于准确的FOnK判断，准确的FOK判断引发一个更负的波（N4），最高波幅出现在线索词刺激出现后500ms。并首次观察到FOK与FOnK在400ms左右开始发生分离。

研究意义：本研究从行为实验和ERP两方面验证了知道感的“双过程假设”，为这一假说提供了实证支持。

In the past, almost all theories supposed that FOK was a continuum of subjective feeling, from weak to strong. Recent neuroimaging studies implied that FOK and FOnK might be sub-served by different cognitive and neural processes. The aim of the present study is to validate this theory from both behavioural and ERP experiments.

Behavioural experiments: we manipulated four variables: learning degrees, semantic relatedness, cue-word frequency, and non-word. We tested their effect on FOK and FOnK using a standard Recall-Judgment-Recognition (RJR) procedure. The results showed: the variables mentioned above had reverse effect on FOK and FOnK: learning degrees, semantic relatedness and high-frequency cue-words promoted the prediction accuracy of FOK (PA-FOK) while decreased the prediction accuracy of FOnK (PA-FOnK). Low-frequency cue-words and non-word pairs had the reverse effect that enhancing PA-FOnK while reducing PA-FOK.

ERP experiment: this is the first attempt to investigate FOK with ERP, using the high temporal resolution of ERP, we can further demonstrate when the judgment of FOK and FOnK begin to dissociate. Unrelated word pairs formed by nouns were employed to go through the same procedure as the behavioural experiment. Result indicated: we found PP items elicited a more negative ERP deflection than did NN in the time interval between 400–600 ms. It appeared that the peak latency of the negative component was about 500ms (N4) post-stimulus onset, moreover, we first observed the disassociation of FOK and FOnK at about 400ms.

Research meaning: The research testified the “double process hypothesis” of FOK from behavioural and ERP experiments, providing demonstrational evidence.