憂鬱反芻對工作記憶容量的影響之初探

Abstract

前言：過去文獻顯示憂鬱反芻是維持個體憂鬱狀態的重要關鍵，然而近來研究指出憂鬱反芻的概念可區分為苦惱自責和深思反省兩個因素，分別對應於反芻思考的不適應性以及適應性的面向。另一方面，以認知功能角度探究反芻持續的可能作用機制，目前有反芻傾向為認知功能缺損者的外顯表徵，以及反芻歷程耗費個體認知資源兩種觀點，但都有待後續研究加以驗證。目的：本研究企圖以實徵研究方式初探反芻傾向、反芻狀態與工作記憶容量之關聯。方法：研究一旨在 發展憂鬱反芻反應的測量工具，以220 名大學生為樣本，檢驗中文反芻反應風格量表短版在本地的心理計量特性與因素結構，並驗證憂鬱反芻兩因素模型。研究二旨在發展中文操作廣度作業，建構難度相當的平行版本作為後續研究的工具，以測量個體在接受操弄前後之工作記憶容量。研究三包含兩個實驗，實驗一以70名大學生樣本檢驗反芻思考是否消耗認知資源。實驗二以另外58 名大學生為受試者，在反應作業操弄前進行悲傷情緒的誘發，初探憂鬱反芻對於認知功能的影響。結果：綜整研究結果顯示：（1）中文反芻反應風格量表短版具有良好的心理計量特性，並且苦惱自責分量表與憂鬱症狀嚴重度有顯著正相關，但深思反省分量表則與之無關，支持憂鬱反芻為多向度之概念。（2）反芻思考歷程本身無法引發負面情緒或造成受試者認知功能的缺損。（3）一般受試者在誘發悲傷情緒後進行反芻作業，並未展現情緒或執行功能上的負面效果。值得注意的是，深思反省傾向高分組在悲傷情緒復原後，工作記憶容量表現顯著優於低分組。討論：最後以思考內容的情緒價、樣本特性等結構層面探討憂鬱反芻理論的應用範圍，並說明研究結果在臨床應用上的啟示，以及未來可行的研究方向。

Introduction：Literature review shows that depressive rumination sustains depressed mood. However, recent studies have suggested of two separated subcomponents of depressive rumination, i.e., brooding and reflection, representing the maladaptive and adaptive cognitive aspects of depressive rumination, respectively. From another point of view, some researchers proposed that there were cognitive mechanisms accounting for the persistence of rumination process, i.e., the tendency to ruminate is the results of individual’s cognitive impairments or rumination itself occupies one’s cognitive resources. Both hypotheses need to be further examined. Purpose：Thus, the present thesis aimed to empirically investigate the relationship among rumination tendency, rumination process and working memory capacity. Method：Study 1 examined the psychometric properties of the Chinese version of the Rumination Response Scale-Short Form (CRRS-SF). It validated a two-factor model of depressive rumination by using a sample of 220 undergraduate students. Study 2 developed the Chinese version of operation span task, and resulted in two parallel sets of items equivalent in difficulties for evaluating subjects’ working memory capacity pre- and post- manipulation in the next study. Study 3 consists of two experiments. Experiment 1 was designed to examine whether the rumination process occupied cognitive resources in 70 undergraduate students. In experiment 2, another 58 students were instructed to induce sad mood before manipulation in order to further investigate the impact of depressive rumination on cognitive function. Results：All in all, the results indicate that: (1) The CRRS-SF yielded adequate psychometric properties. Moreover, scores on the brooding subscale, rather than reflection subscale, were significantly positively correlated with depressive symptoms. The results supported a satisfactory two-factor construct of depressive rumination. (2) Rumination process alone, in the absence of depressed mood, was not able to elicit participants’negative emotions or impair their cognitive function. (3）Normal subjects with sad mood induction did not show deleterious effects on mood or executive function after ruminating. Notably, participants with higher scores on reflection subscale showed greater working memory capacity than participants with lower scores after remediation from sad mood states. Discussion：Based on the findings, the structure aspects such as the valence of thought contents and subjects’ characteristic were discussed to elucidate the appropriateness of applying the theory of rumination in non-clinical samples. Possible application and future directions were also addressed.