刺激呈現次序是否能誘發規則：由轉換虧損驗證

Induce Rules by Stimuli Presentation Sequences: Evidence from Switch Cost

人們具有在事物間尋求關係的傾向，並且容易衍伸出規則以作為準則。Dreisbach、Goschke及Haider（2007）以漸進式方式介紹刺激給受試者，發現若告知受試者規則，則在不同規則之間轉換會產生轉換虧損，不告知背後隱藏的規則即無，顯示知曉規則會導致轉換虧損。本研究的目的即測試是否只要介紹刺激的順序恰當，即便不告知規則也可能讓受試者揣摩出規則，進而產生轉換虧損。我們操弄兩種順序：先將屬於同一規則的刺激材料介紹完再介紹另一規則的刺激（稱為誘發規則組），以及同時跨規則地介紹刺激（稱為刺激反應組）。在實驗一中我們重複Dreisbach等人（2007）的實驗，結果驗證誘發規則組可產生轉換虧損。實驗二發現若兩個隱藏的規則都可直觀查覺，則刺激反應組也可產生轉換虧損。實驗三和四顯示，當隱藏的規則之一可直觀查覺、而另一個較不直觀時，則不論哪一種規則的刺激先介紹完，誘發規則組都會出現轉換虧損而刺激反應組無。本研究的結果顯示，即便沒有告知規則，將屬於同一規則的刺激先介紹完可以促使受試者較易推敲出隱藏的規則。而隱藏的規則若符合直觀，則不需要特定的刺激呈現次序也可促使規則的衍生。

People tend to find correlations among different events and create specific rules to follow. Previous studies have shown that switching between different rules takes time; this is called the switch cost. Dreisbach, Goschke, and Haider (2007) introduced two stimuli at a time in each section and found that without debriefing the underlying rules of these stimuli, no switch cost could be observed. However, we argue that, with a proper sequence of adding stimuli to the experiment, participants should be able to generate rules by themselves. We hypothesize that successively presenting stimuli with the same rule (the induction group) could promote generation of the rule, as compared to mixed presentation of stimuli with different rules (the stimulus-response group). In Experiment 1, we asked participants to press keys following specific stimulus-response mappings without telling them the underlying rules, and found significant switch cost in the induction group but not in the stimulus-response group. Experiment 2 demonstrated that if the two underlying rules were highly perceptible, the stimulus-response group as well as the induction group could show significant switch cost. Experiments 3 and 4 revealed that when only one of the two underlying rules was perceptible, regardless of which rule was introduced first, only the induction group showed significant switch cost. Taken together, our findings suggest that rules can be induced via appropriate presentation sequence, except that the hidden rules are highly perceptible.