過去研究發現，情緒會影響認知執行作業的表現，而正負向情緒分別有著不一樣的效果，Ashby等人提出的多元分類系統（Competition between verbal and implicit system，COVIS），包含一外顯系統，涉及的是工作記憶與假設檢定，而該系統會因好心情，增加多巴胺濃度並作用在前額葉區，故據COVIS理論，正向情緒會增加認知彈性，使需要投入注意力的外顯作業，學習表現更好，但內隱系統涉及的是不同的腦區活動，故內隱作業歷程不受任何情緒的影響。而從另一觀點，根據認知捷思，正向情緒狀態，會促動認知捷思歷程，因為好心情降低對周遭訊息處理的動機，而多數認知執行作業，需要審慎考慮的分析以及注意力的控制，所以從動機論的觀點，預期正向情緒會損傷認知執行作業的表現，相對的，負向情緒讓個體警覺，進而提升對周遭訊息處理的動機，使人們會更加小心翼翼，採用系統式分析歷程，故在此觀點下，負向情緒可以提升認知作業表現。本研究進一步釐清，探究在正向及負向情緒下，到底哪種情緒會增進分類學習的正確率表現。實驗一、二、三主要的目的，在複製出Nadler（2010）研究結果，即正向情緒助長了外顯系統作業表現，由於實驗一的情緒誘發素材成份過於複雜，無法複製出Nadler（2010）相同的結果，實驗二進而使用更純粹誘發素材，實驗結果支持認知捷思的觀點，即負向情緒，提升了受試者分類學習表現，實驗三進一步確認，情緒激發水準在情緒對分類學習影響下所扮演的角色，研究結果顯示，情緒的激發水準確實調節分類學習表現，尤其在正向情緒下，高激發水準會損傷外顯學習系統作業表現，低激發水準時，則助長外顯作業系統的學習表現，故COVIS理論的預期，正向情緒有比較好的外顯作業學習表現，唯情緒激發水準低時，方能實現。

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