正常老年人事件記憶知感的研究

Abstract

對於正常老年人事件記憶『知感』能力是否退化的研究，由於方法上的問題，導致結果不一致；而過去對於正常老年人『知感』表現與其額葉功能退化有關的研究較少；加上部分研究取樣的老年人，平均教育程度較國內一般老年人偏高，是否可以直接運用國外研究結果至國內樣本，仍需進一步探討。因此，本研究改善國外研究方法上的缺失，嘗試建立本國一般教育程度老年人『知感』能力的資料；並進一步探討正常老年人『知感』運作可能的神經心理機制。主要的研究問題包括：（1）正常老年人事件記憶『知感』相較於正常年輕人是否呈現退化？（2）正常老年人的『知感』表現與其額葉功能的退化是否有關？本研究包括正常老年人與年輕人兩組共69位受試者，在性別、教育程度、以及語文智力上配對，每位受試者均接受相關神經心理測驗的施測與研究『知感』現象的RJR（recall-judgment-recognition）派典。研究結果發現：1）正常老年人與年輕人在事件記憶『知感』的正確性沒有差異。2）正常老年人的『知感』表現，與其額葉功能退化有關。本研究結果支持部分研究（Perlmutter, 1978; Souchay, Isingrini, & Gil, 2002），發現正常老年人事件記憶『知感』能力與年輕人沒有差異；且進一步證實過去文獻（Souchay, Isingrini, & Espagnet, 2000），認為正常老年人的『知感』表現與其額葉功能的退化有關。然而，本研究藉由相關分析的結果，推論老年人事件記憶『知感』之神經機制，是一限制。未來研究可加入測量相關的神經影像學資料，來加以定位正常老年人的『知感』表現與腦部位功能退化的關係。

The issue of whether aging affects the feeling-of-knowing (FOK) function of episodic memory has been controversial. Methodological drawbacks, such as inadequate FOK measures and confounding variables of the demographical data might account for such inconsistent findings. In order to clarify this debatable issue, the author made an attempt to minimize these pitfalls in the present study. Furthermore, the literature regarding neuropsychological mechanism of FOK in Taiwanse aging has been lacking. Thus, the primary objectives of this study were to explore episodic memory FOK function in normal aging and its possible neuropsychological mechanism. Thirty-four normal older adults and thirty-five normal young controls matched for sex, education level and VIQ of the WAIS-R were participated in the study. Each participant received a series of neuropsychological test batteries and RJR paradigm. The results revealed: (1) that FOK accuracy did not vary by age, and (2) FOK judgment task performance in normal aging was significantly correlated with certain frontal neuropsychological measures, while normal young participants’ judgment performance was remarkably correlated with episodic memory function tests. On the basis of the results, it appeared that the underlying neuropsychological mechanisms for FOK judgment of episodic memory between normal aging and their normal young counterparts were different. However, since this conclusion was merely based on neuropsychological measure correlates rather than on the structural or functional neuroimaging findings, further investigation thus is merited.