高次認知能力と作動記憶容量の個人差に関する検討 : 言語性および視空間性認知課題を用いて

Abstract

本研究では, Shah & Miyake (1996)やBayliss et al.(2003)を踏襲し, 処理課題と記銘項目に言語性材料あるいは視空間性材料を用いた作動記憶スパンテストを作成して, 言語性および視空間性の高次認知課題とともに実施し, (1)言語性作動記憶容量は言語性認知能力と, 視空間性作動記憶容量は視空間性認知能力と, それぞれ領域選択的に有意な相関を示すか否か, そして(2)作動記憶スパンテストにおける処理の速さや正確さといった処理効率を統制したときでも, 作動記憶スパン成績の個人差は高次認知課題の成績の個人差を有意に予測する説明変数となりうるか否かを検討する｡

This study demonstrates the domain-specific contribution of verbal and spatial working memory (WM) capacity to complex cognitive ability among adults. Four kinds of WM span tests were developed by combining a verbal or spatial processing task with a verbal or spatial memory material. The verbal-verbal memory span correlated with a verbal cognitive measure, but not with a spatial cognitive measure; the reverse was true for the spatial-spatial memory span. The verbal-spatial and spatial-verbal memory spans, however, showed no such domain-specific pattern in correlation with the complex cognitive measure. Furthermore, the verbal-verbal and spatial-spatial memory spans sustained a significant predictive power for the cognitive measure involving the same kind of representation even after controlling the processing efficiencies, whereas the verbal-spatial and spatial-verbal memory spans did not. The findings confirm that a domain-specific factor of WM capacity is reflected in high-level cognitive performance, but many recent studies employing a latent-variable analysis provide support for a domain-general view of WM capacity. It is suggested that we should acknowledge the substantial influence of resistance to domain-specific representational interference as well as domain-general executive control on complex cognition and intelligence.