如何提升兒童的科學推理表現－探討練習時認知負荷量與工作記憶廣度的影響

Abstract

在模擬科學發現情境的作業中，受試者必須自行設計實驗加以測試、觀察，並依據實驗結果歸納出新假設或修改既有假設，最終找出影響效果的規則。關於兒童科學推理的研究發現，兒童不但在相同作業中的表現較成人差，在相同練習中的進步亦未如成人明顯而全面。且同年齡兒童在推理作業中的表現存在很大的變異，變異程度甚至隨著發展而提升。而研究也發現工作記憶與許多高階的認知歷程息息相關。因此本研究從工作記憶的觀點，首先探討兒童的科學推理表現與其工作記憶廣度的關係。此外我們嘗試以電腦輔助工具降低練習時的認知負荷量，以期促進兒童的推理發展，並分析其進步程度是否受到工作記憶廣度的影響。兩組五年級學童事先接受工作記憶廣度測量，並分別在高、低負荷量下進行科學推理練習。練習前後皆接受推理能力測量。我們的研究結果發現，工作記憶廣度越大的兒童越可能設計有效的實驗以檢驗假設，而且較能依據證據做出合理的推論。而降低練習時的認知負荷量也使得兒童對於重要實驗策略的掌握有所提升，並且更能考慮實驗證據而做出合理的推論。同時在認知負荷量較高的情況下練習的兒童進步則不明顯。另外，當環境支持兒童的推理發展時，他們的進步程度亦受到工作記憶廣度的限制而有所不同。顯示無論環境的工作記憶需求或個體本身的工作記憶條件都會影響兒童推理的表現與提升。

In self-directed experimentation tasks, participants have to conduct experiments to infer the relationship between variables and a certain effect. Previous research has shown that in this kind of task, children performed worse and progressed less rapidly than adults. There was also large variability among subjects of the same age. Research has also found that participants reasoned less correctly under high working memory load, and that working memory capacity is an important predictor of performance in deductive reasoning tasks. The main objectives of this research are to investigate the relationship between children’s working memory capacity and their scientific reasoning ability, and the possible influence of cognitive load on practice effect. Two groups of sixteen 5th-graders participated in scientific reasoning exercise under high or low cognitive load respectively; their reasoning abilities were measured both before and after the exercise. The results showed that children with greater capacity were more likely to design controlled experiments, and better coordinate their inferences with collected data. In addition, children exercised under lower cognitive load progressed more significantly in scientific reasoning skills. Meanwhile, only individuals with greater capacity progressed significantly through low load practice. The findings suggest that working memory capacity play an important role in children’s performance and development of scientific reasoning, and that lowering cognitive load during practice facilitate children’s improvement.