ISSN : 1226-9654
본 연구는 공간적 위치를 달리하는 둘 이상의 항목에 분산된 서로 다른 시각적 세부특징에 대한 저장 요구가 시각작업기억의 저장 효율성에 미치는 영향을 조사하였다. 이를 위해 실험 1의 분할기억 조건에서는 좌우 시야 중 한 쪽에 특정 세부특징(예: 색상)을 보유한 기억항목이 그리고 반대편 시야에는 다른 세부특징(예: 방위)을 보유한 기억항목들이 제시되었다. 반면, 단일기억 조건에서는 색상 혹은 방위 차원 중 하나로만 구성된 기억항목들이 제시되었다. 두 조건에서 참가자는 개별 기억항목들의 색상과 방위를 기억한 뒤 1초 뒤에 제시되는 검사자극과 비교해 색상 혹은 방위 차원의 변화 유무를 보고하였다. 실험 1의 변화탐지 정확도를 분석한 결과 분할기억 조건의 변화탐지가 전반적으로 더 정확하되, 요구되는 기억항목의 개수가 증가할 경우 이러한 차이는 더욱 커졌다. 실험 2의 분할기억 조건에서는 기억항목을 둘 이상의 세부특징으로 구성하되(예: 색상+방위 막대), 검사항목 출현 시 변화 가능한 세부특징을 좌우 시야에 각각 색상 혹은 방위 차원 중 하나로 지정하였다. 통합기억 조건에서는 좌우 시야 구분 없이 전체 항목 중 무선 선택된 한 항목의 색상 혹은 방위 차원에서 변화가 발생하도록 처치하였다. 그 결과 분할기억 조건에서 평균적으로 정확한 변화탐지 정확도를 관찰했으나 항목개수의 증가에 따른 두 조건 간 현격한 차이는 발견되지 않았다. 이와 같은 결과는 통합된 객체 모형이나 병렬-독립 저장 모형보다는 약한 객체 가설을 지지하는 결과라 할 수 있다.
The present study examined Visual Working Memroy (VWM) storage efficiency when items with different features are displayed across different positions. In separate-memory condition of Experiment 1, either colored boxes or orientation bars were displayed respectively on either side of the visual fields as memory items whereas the items were all colored boxes or orientations bar in a control condition. Subjects were asked to remember the features of the memory items followed by a brief memory delay. After the delay, test items were displayed and subjects reported presence or absence of a change in either color or orientation across the memory and test items. The results showed that change detection performance was significantly higher in the separate memory condition than the control condition. Also, the difference became more apparent if the set size became larger. In Experiment 2, the items in separate-memory condition were replaced with colored orientation bars (i.e., conjunction items). The change in the test items could occur in either color or orientation dimension, but the side of visual fields for its occurrence was designated exclusively for each features (e.g., left for color vs. right for orientation). In the control condition (i.e., integrate-memory condition), no such constraint was present and either color or orientation change could occur randomly across the sides of visual fields. The results showed that the difference in change detection performance between separate-memory and the control conditions was greatly reduced, and no differential effect of the setsize manipulation was observed across each condition. These results support the weak-object hypothesis where items in VWM are represented flexibly either as a form of well-bound features or of independently-stored discrete features. rather than the strict models according to integrated-object or parallel-independent storage hypothesis.
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