具被害妄想的思覺失調患者之自我記憶偏誤與注意力控制能力

研究背景與目的. Bentall等人（2001）認為被害妄想是提升自我評價的防衛機制，以避免個體被內外差異所造成的苦痛感所影響。此外，被害妄想也被認為與注意力控制較差及誇大自利偏誤有關，本研究將從記憶偏誤的部分進行切入，並針對上述觀點進行驗證。因此本研究的主要目的有三點：第一，探討具有被害妄想的思覺失調患者在自我表徵上是否會藉由記憶偏誤而有所不同；第二，對比其他組別，注意力控制能力是否在具有被害妄想的思覺失調患者具有明顯差異；第三，內外在自我表徵差距與注意力控制能力之間的交互作用。研究方法. 本研究為3 x 3的二因子混合設計，受試者間變項為組別（兩組病患者，各30位有無被害妄想的思覺失調症患者，以及30一般成人控制組），受試者內變項為實驗刺激的詞彙價性（正向詞、憂鬱詞、及威脅詞）共招募90名受試者。實驗透過個人參照派典進行，將分為自我參照判斷階段及自我參照偶發學習階段依序進行。判斷階段將呈現15個正向字詞、15個憂鬱字詞以及15個威脅字詞，請受試者選答該字詞是否描述自己與自己有關；偶發學習階段則分為回憶及再認部分，回憶階段要求受試者盡可能回憶上階段曾經出現過的字詞、再認部分則是加入同樣性質數量的新詞要求受試者進行判斷是否在判斷階段曾經出現過。注意力控制能力則藉由「注意力控制量表」要求受試者填答，同時透過GPTS以及PANSS測量評估受試者的被害妄想症狀嚴重程度。研究結果. 具被害妄想組別透過記憶偏誤的歷程，相較健康控制組顯示出較少的自利偏誤，這也代表具有較為負向的內外在自我表徵，其中對於威脅字詞的精緻化處理程度顯著高於健康控制組。再者，注意力控制的部分同時也發現被害妄想患者的得分較低，也呈現出具有被害妄想意念越高則注意力控制能力越低的情形。最後，注意力控制對於「判斷－選擇再認」自利記憶偏誤差異具有調節效果，代表此兩者對於被害妄想意念結果的產出具有顯著交互作用。結論. 被害妄想患者具有明顯負向自我表徵及較少的自利記憶偏誤，同時注意力控制能力表現也較差，另外內外在自我差異與注意力控制之間則具有顯著的交互作用。本研究於討論中，亦針對本次結果於理論及臨床的意涵進行探討，並嘗試提出本研究的限制與對未來研究的建議。

關鍵字

被害妄想；記憶偏誤；個人參照；注意力控制；自我表徵

並列摘要

Background and Purpose. Bentall and his colleagues (2001) suggested that persecutory delusion function to enhance self-evaluation and help individuals avoiding distress triggered by latent negative self- representations and the discripency of self. It has been found that persecutory delusion robustly associated with low attentional control ability and exaggerate cognitive bias. The purpose of the present study was threefold. First, it aimed to investigate the memory bias about self in schizophrenia with persecutory delusion. Second, it tried to compare the abilities of attentional control between groups. Third, it tried to examine the effects of interaction beteen attentional control and the discipency of self-representation. Methods. Base on these purposes, the study 3 x 3 mixed design to test the self-representation in schizophrenia patients with persecutory delusion. The variable of between subjects is group (30 schizophrenia patients with persecutory delusion, 30 schizophrenia patients without persecutory delusion, and 30 healthy control) . The variable of within subjects is word valence include positive, depressive, and threatening words in self-reference judgment and incidental learning task. In self-reference judgment task, we asked subjects to choice yes/no from each word, it stand for his/herself. In self-reference incidental task, one of the process is recall stage, all of the subject needed to recall the word from the judgment task as much as possible. In the recognition task, all of the subject needed to recognized the word from the judgment task. We used the Attentional control scale to measure the abilities of attentional control between subjects. Moreover, tested the severity of paranoia from the GPTS and PANSS. Results. Compare to the control group, the results showed that schizophrenia patients with persecutory delusion had less self-serving memory bias in all of task, it means that schizophrenia patients with persecutory delusion had negative self-representation no matter what it be, specially at the “threaten stimulation”. At the same time, we found schizophrenia patients with persecutory delusion had lower attentional control abilities. Finally, The results showed that “attentional control abilities” were the moderator betwwen the discripency of “ choiced judgment-recognition task” and the “paranoid ideation”. Conclusions. To summarize, schizophrenia patients with persecutory delusion had less self-serving memory bias and lower abilities of attentional control abilities, and there were interaction effect between “the discripency of self-serving memory bias” and “attentional control abilities”. Theoretical and clinical implications of these results were discussed.