錯誤在幼兒觀察學習工具使用的角色

Abstract

發展學家以研究靈長類使用工具行為的陷阱管子，探討幼兒觀察錯誤的學習歷程，顯示2歲幼兒不理解錯誤提示的動作因果，沒有複製示範以工具取物的模仿增進效果，卻能用自己知道的作業物理知識，透過仿效途徑改以其他方法取物。然而，過去研究未排除失誤、重置、最後成功取物的大人錯誤示範，失誤與取物兩動作之間的重置，是否導致幼兒注意新近的成功取物動作、忽略初始的失誤動作，以致於沒有整合兩動作之間的關聯，難以產生掌握用工具取物因果的模仿學習。本研究旨在探討錯誤示範程序對2歲幼兒模仿使用工具的影響，進一步釐清錯誤伴隨的意圖目標線索與因果結構訊息，是否引導幼兒的目標仿效學習。\n實驗1檢視錯誤示範的重置步驟，造成兩動作的顯著程度差異，是否干擾幼兒組織兩動作與取物的因果規則，導致模仿困難。如果錯誤訊息的顯著性提升，有利於幼兒整合兩動作的因果關聯，省略錯誤示範中的重置步驟，應增加幼兒成功複製示範方法以取物的模仿表現。結果發現，不論幼兒看的錯誤示範中有無重置步驟，都沒有增進理解用工具取物因果的模仿成功率，但幼兒看包含重置的錯誤示範，有偏好以示範方法取物的模仿表現，看省略重置的錯誤示範，相對有利於用其他方法取物的目標仿效表現。\n實驗2檢視在省略重置的錯誤示範下，幼兒產生取物目標仿效的原因，是否來自保留現場的失敗結果，提供了錯誤的記憶線索，有助於幼兒瞭解先失誤後取物的事件關聯，並表徵兩事件的主要目標為取物。如果錯誤記憶提升錯誤的顯著性，是幼兒產生取物目標仿效的導因，即使錯誤示範中有重置步驟，移除了提示錯誤記憶的失敗結果，只要在成功取物前，記憶強化失敗結果以提升錯誤顯著性，幫助幼兒整合兩事件並表徵目標，應同省略重置的錯誤示範情境，幼兒不會產生取物的模仿偏好，有利於取物的目標仿效表現，另一方面，在省略重置的錯誤示範情境，留下來的失敗結果，也可能突顯大人的失誤為意外而取物為意圖目標，幫助幼兒瞭解大人在情境中的整體目標為取物，並產生取物的目標仿效學習，如果意圖線索是幼兒取物目標仿效的導因，當大人在包含重置的錯誤示範中，口語和表情將錯誤也標示為意圖目標，不提供偏好特定物件結果的意圖線索，也無法即時視覺比對兩物件結果，以致於整個情境的意圖訊息弱化，應相比省略重置的錯誤示範情境，減少幼兒取物的目標仿效表現。結果發現，不論包含重置的錯誤示範中，加強記憶線索以提升錯誤顯著性，或者減弱意圖線索對整體情境目標的烘托，幼兒模仿與仿效取物的表現，皆與看省略重置錯誤示範的幼兒有相似偏好，表示大人錯誤示範時，加強錯誤記憶以降低成功取物事件的顯著程度、提升錯誤顯著性，會削弱幼兒模仿取物的傾向，有利幼兒取物的目標仿效表現，但幼兒取物的目標仿效表現無關大人意圖。\n實驗3檢視大人意圖在幼兒目標仿效歷程中沒有扮演角色，是否因錯誤本身引導幼兒注意物件在管子的因果結構，引發幼兒透過仿效途徑，完成作業預設的取物目標。如果錯誤示範彰顯的作業因果結構，是指引幼兒聚焦作業目標並引發取物目標仿效的主因，當情境中的大人口語與表情皆標示取物為失誤，應不影響幼兒以作業目標為主的取物目標仿效表現，也應與沒有示範只有作業本身訊息的情境，有相似的幼兒取物目標仿效表現，結果發現幼兒偏好完成取物結果，而非偏好重現失誤結果，且比沒有觀看示範的幼兒，有較多用示範方法取物的表現。\n整體而言，錯誤示範的錯誤顯著性高，有助於幼兒表徵示範事件的主要目標，進而產生目標仿效學習，錯誤的顯著性低，則幼兒傾向保守模仿示範的動作與結果，此外，觀察錯誤比觀察單純正確，提供幼兒更多對作業產生基本認識的機會，誘發幼兒動用自身因果知識、探索問題的解決方法。由於陷阱管子是特定因果結構作業，作業設計的工具性目標，主導了幼兒的目標仿效學習，雖然此強勢效應無法被大人示範提供的意圖線索所覆蓋，但大人提供了動作方法的參考，也在溝通互動情境下暗示了社會性訊息，這些來自大人的觀察線索，有調節幼兒選擇模仿與仿效學習策略的效果。

Trap-tube is a classic tool-use task to explore primate learning behavior. Developmental scientists have been employed trap-tube to study children`s observational learning from others’ mistakes. All studies show that 2-year-old children could not understand the causal effect of retrieving rewards by the tool so that they have no improvement of imitative learning. However, children know about the task physics and they can still retrieve rewards successfully in other ways via emulation. Despite the findings, the demonstration sequence of mistakes in previous studies included mistakes, reset tasks, and successful attempts. This situation might lead children to only focus on the last successful retrieve but neglect the initial mistake. Thus, they consequently could not integrate the association between the two actions, which made them had difficulty in imitative learning. Therefore, the purpose of this study was to investigate the effect of the resetting procedure in the mistaken demonstration on imitation of tool use in 2-year-old children and to clarify whether the intentional goal and causal structure behind the mistake induce emulative learning.\nExperiment 1 examined whether the reset step of mistaken demonstration (restored demo), which resulted in a difference of salience between the two actions, interfered with children`s integration of the two actions of causal association and thus led to children’s difficulties with imitation. If the salience of mistake is helpful for children to imitate the retrieving action by the tool, children`s imitation performance should be improved when the restored demonstration had omitted the reset step (retained demo). Nevertheless, it was found that whether the mistaken demonstration included reset procedure or not, children`s imitation performance was not facilitated. But children well used their own way to retrieve the reward through goal emulation when they observed retained demonstration.\nExperiment 2 examined whether the reason for children`s goal emulation after they observed retained demonstration was the trapped reward, which was kept in the situation till the end, providing a memory cue for initial mistake. The memory cue helped children to recognize the association of the mistaken event followed by the successful outcome and supported children to represent from the previous events that the main goal is to retrieve the reward. If the salience of mistake is enhanced by the memory cue and then induced children’s goal emulation, children’s imitation and emulation performances would be similar to those children who observed retained demonstration when they observed restored demonstration was presented to emphasize the memory of mistake before it showed the successful outcome (memory demo). On the other hand, based on the previous mistakes, the demonstrator’s mistaken demonstration and intentional goal of retrieving the reward might be highlighted. Thus it will be beneficial to children to comprehend the main goal of the holistic situation in the retained demonstration. If the intention cue helped children to realize the main goal and provoke children to emulate the retrieving outcome, children`s emulation performance should be less than those children who observed retained demonstration when they observed the demonstrator’s verbal and facial expressions mark the mistake as an intended goal and show no preference towards the pre-and-post outcomes (two-goal demo). It was found children observed the demonstration regardless of whether the memory cue was strengthened or the intention cue was weakened. Both of Their imitation and emulation performances had no differences from those who observed retained demonstration. All that means when children observe the mistaken demonstration, salient mistakes will decrease their imitative learning and persuade their emulative learning. But there is no relation between the demonstrator’s intention and children’s goal emulation.\nExperiment 3 examined whether children could retrieve the reward via goal emulation that was triggered by the mistake which guided children to notice the causal structure of trap-tube and the instrumental goal of the task. If the causal structure of the task behind the mistaken demonstration was the core reason for leading children to retrieve the reward, it should not affect the children`s resulting retrieve performance when the demonstrator`s verbal and facial expressions indicated that the retrieve was a mistake (reverse demo). Besides, these children’s retrieving performances would be similar to those children who did not observe any demonstration (baseline). It was found that children preferred to complete the retrieval task rather than to reproduce the mistaken outcome. They adopt the preset tool-use method to retrieve the reward more often in reverse demonstration than those in the baseline condition.\nIn conclusion, when children observe the mistaken demonstration, high salience of mistake is helpful for them to represent the goal and emulate the outcome. On the contrary, when the situation is low salience of mistake, it makes children bring out imitation more than emulation. In contrast to only observe correctly, children have more opportunities to be aware of the affordances and causal structure of the task through observing mistakes. The basic understanding of the task induces them to use their own causal knowledge to explore the solutions to the problem. To be mentioned the trap-tube is an instrumental task, which is well designed in a specific causal structure so that the task goal dominates children’s emulation performance but not the demonstrator’s intentional goal. However, the demonstrator’s actions and social cues during communicative learning situations will moderate children’s selection of strategies between imitation and emulation.