- 學位論文
具被害意念之非臨床群體的記憶偏誤：自我及他人參照判斷與偶發學習研究
Memory bias in subclinical population with paranoid ideation: self-reference and other-reference effect in judgment and incidental learning tasks
摘要
研究背景與目的. Bentall等人(1994)認為被害意念是提升自我評價的機制，以避免個體被其潛在的負向自我表徵所影響，造成憂鬱情緒困擾。研究證據指出，被害意念與自尊的自陳報告有穩定的負相關；但亦有研究指出在控制了憂鬱情緒後，發現高被害意念者有平均以上的自我評價。除了負向自我評價與憂鬱情緒有尚未釐清的關係以外，以行為作業研究高被害意念者的潛在負向自我也尚未能得到一致的證據，需要以有效的作業來進行探討潛在自我評價的主題。Freeman(2007)認為被害意念是種以威脅為主的認知信念，源自於個體對他人的不信任及對自己的脆弱感，為個體在焦慮情緒下對其所感受到的經驗所提出的解釋。雖然目前已有初步證據顯示高被害意念者有自陳的負向他人評價，但現今未有足夠的研究聚焦於個體對特定他人的信念，例如：權威他人，此外也缺乏研究以行為作業來探討高被害意念者對他人評價的主題。Trower與Chadwick(1995)認為有兩種被害意念，若能在非臨床群體中有效區別出此兩種被害意念，則可說明過去研究發現的不一致，即被害意念與高憂鬱及低自尊有穩定的相關，但同時又有證據指出高被害意念者具有自利偏誤。 研究方法. 分為三個研究進行。研究一以先針對一般大學生進行量表團體施測，包括Green被害妄想量表(GPTS)、貝克憂鬱量表第二版(BDI-II)、特質焦慮量表(STAI-T)，並以群集分析探討高被害意念者是否可再區分出其他次群體，接著以施測簡短核心基模量表(BCSS)及評估其知覺應受迫害程度(perceived deservedness of persecution)，以作為群體分析的外在效標。研究二參與者為24位高被害意念高憂鬱組，24位高被害意念低憂鬱組，24位為低被害意念組，以正向詞、憂鬱詞、及威脅詞作為受試者內變項，進行自我參照判斷及偶發學習作業(SRILT)，並比較選取的詞數、偶發回憶作業時回憶詞數、再認作業時的再認成功率、以及自利傾向。研究三分為兩個實驗，與研究二的進行程序均相同，為進行的是他人參照判斷及偶發學習作業(ORILT)，實驗一為權威他人參照，實驗二為一般他人參照，也是三個組別所選取的詞數、偶發回憶作業時回憶詞數、及再認作業時的再認成功率、以及他利傾向。 研究結果. 研究一以群集分析於非臨床群體中區分出三個群集，群集一特色為低被害意念、低憂鬱、及低焦慮特質，群集二的特色為高被害意念、高憂鬱、高特質焦慮，群集三的分數介於前二者間，群集三有較群集二高的知覺應受迫害感。研究二發現高被害意念組若未伴隨憂鬱，則與控制組一樣選取較多正向詞及較少憂鬱詞，若伴隨憂鬱則選取相同數量的正向詞與憂鬱詞，偶發回憶的結果雖大致與選取一致，但在兩個高被害意念組內皆發現選取與回憶的自利傾向有差距。研究三在權威他人參照實驗中並未發現明顯的組別間差異；在一般他人參照實驗中，兩個高被害意念組均比控制組選取較多的威脅詞，在高被害高憂鬱組更進一步發現選取較少正向詞且回憶出較多威脅詞。 結論. 研究一的證據顯示非臨床群體中有兩種型式的被害意念，雖然兩者的被害程度有高低之分，然而在對於自我信念、對他人信念、知覺應受迫害感上有所差異，可能為被害意念發展的不同階段。研究二顯示未伴隨憂鬱的高被害意念者，主觀的自我評價高於記憶表徵的自我評價，且並未發現負向記憶偏誤；若伴隨了憂鬱則有負向的記憶偏誤，主觀上對自我評價更負向。研究三顯示，高被害意念者在主觀與記憶中對一般他人的評價皆偏向負面，若伴隨了憂鬱情緒則在主觀上對他人正向評價有更低的情況，並有對一般大眾有威脅主題的記憶偏誤。綜合以上論述，兩個不同類型的被害妄想可以解釋過去在自我評價研究中的不一致證據，在自我參照作業中得到了部份的證據支持被害意念為自我的防衛機轉；但另一方面，在他人參照判斷作業中，亦發現證據支持被害意念反映個體對於他人的威脅信念及本身的負向情感。
並列摘要
Background and Purpose. Bentall and his colleagues (2001) suggested that paranoid ideation function to enhance self-evaluation and help individuals avoiding depression triggered by latent negative self-representations. It has been found that paranoid ideation robustly associated with low self-reported self-esteem. However, there is evidence that self-esteem of individuals with high paranoid ideation is above average when depression was controlled. Furthermore, Studies exploring latent beliefs about self in paranoid individuals have inconsistent results and more evidences adapted experimental dependent measure is needed. Freeman (2007) suggested that the core of paranoid ideation is beliefs of threats. People who view self as vulnerable and others as hostile tend to explain their experience as being threatened against a background of anxiety. There is preliminary evidence from a limited number of studies that points to the relevance of paranoid ideation to self-reported negative beliefs about others. Further research is needed to focus on beliefs about specific others, such as the powerful others, and experimental dependent measure is warranted to investigate the evaluation of others in paranoid individuals. Trower and Chadwick (1995) suggested that there are two types of paranoia. The different types of paranoia may explain the inconsistent research results between paranoia and self-esteem. It is interested that whether different subtypes of paranoia can be found in non-clinical population. Methods. There are three studies. In first study, participants complete measures of paranoid ideation, depression, and trait-anxiety. These scores are subjected to cluster analysis to distinguish between different subtypes of paranoia. To validate the subtypes, participants also complete a measure of beliefs about self and other. Furthermore, we also assess the perceived deservedness of persecution of high paranoid participants by visual analogous scales. In second study, 24 high paranoia with depression participants (DP) and 24 high paranoia without depression participants (P) are recruited from the first study, their paranoid ideation scores are top 30% in whole samples. There are also 24 low paranoia participant (C) recruited from the first study. Subjects are asked to participate in self-reference judgment, incidental recall, and recognition tasks (SRILT) which include a list of 20 positive words, 20 depressive words, and 20 threatening words. We compare the amount of words that are endorsed and correctly recalled, the correct rates of recognition, and self-serving tendency between the three groups. In the third study, 30 high paranoia with depression participants (DP), 30 high paranoia without depression participants (P) and 30 low paranoia participants (C) recruited from the first study. Subjects are asked to participate in other-reference judgment, incidental recall, and recognition tasks (ORILT). The target of other-reference is a powerful other in the experiment 1, and the general others for the experiment 2. We compare the amount of words that are endorsed and correctly recalled and the correct rates of recognition between the three groups. Results. In first strudy, a cluster analysis distinguish between three clusters in non-clinical populations, clusters 1 features low paranoid ideation, low depression, and low trait-anxiety, the cluster 2 features the high paranoid ideation, high depression, high trait-anxiety, and cluster 3 lies between the other two groups in all the three measures.Cluster 3 has relatively high perceived deservedness of persecution than cluster 2. In second study, the pranoid group without depression endorsed more positive words than depressive words as control group, but depressive-paranoid group endorsed same number of positive words and depressive words. Although the result of incidental recall have the same pattern as that in the stage of endorsing words, there are inconsistency between the endorsed self-serving and recalled self-serving in all the paranoid groups.In the third study, there are no significant group differences in powerful other-reference task.In the general other-reference task, all the two paranoid group endorsed more threanting words than control group.Futhermore, the depressive paranoid group endorsed few positive words and recalled more threatening words than control group. Conclusions. Study 1 show the evidence of two types of paranoa in non-clinical population, though they are different at the degrees of paranoia. The two types of paranoia differ in the evaluation of self and others, and also in perceived deservedness of persecution. Study 2 shows that there is higher overt self-evaluation than the self-evaluation in the memorial representations of paranoid group without depression, but the opposite result has been found in depressive paranoid group who have negative memory bias. Study 3 shows that paranoid groups have more negative overt evaluations and more negative memorial representations about general others than the control group. The depressive-paranoid group who have threatening memory bias even has lower positive overt evalution of general others than paranoid group without depression and control group. In sum, the two different types of paranoia may explain the inconsistent evidences in previous reseaches on self-evaluation. Moreover, the evidences obtained from self-reference task partially support the paranoia-as-defense model. Finally, other-reference task also showed that paranoia is the reflection of individuals’ negative affections and beliefs about threatening others.