形似鄰群效果於中文詞彙辨識歷程中所扮演之角色

Abstract

本文探討形似鄰群詞的特性對中文詞彙辨識過程中產生之影響，此為近廿年來拼音文字的字彙辨識研究者們熱切爭論的主題。中文字詞彙辨識研究中，亦有研究者探討類似的議題，可惜相關的研究數量極少，而且不易產生可被其他研究者穩定複驗的實驗結果。本文針對中文語言特性，找出過去研究未能處理的混淆變項，進而提出改善的實驗設計，並進行了研究一、二等一系列之實驗。於研究一中，同時操弄詞頻和鄰群詞數目大小，並控制平衡目標詞中的首字頻率，探討它們對於中文詞彙判斷和詞彙唸名兩種認知作業的影響。結果發現，無論詞頻或作業為何，參與者於目標詞伴隨較大鄰群詞數目的情況下，比目標詞伴隨相對較小鄰群詞數目的情況下，產生了較短的反應時間，顯示出極為明顯的鄰群詞數目大小之促進效果。一個可能的解釋如下，由於鄰群詞之間共享著相同字形的特定字彙，使得鄰群詞之間往往有著相近的語義，逐漸形成了一種語義網絡，進而導致了語義的激發並產生促進的效果，加速了參與者對於目標詞的辨識。此外，相異於拼音文字系統，中文詞彙中的鄰群詞頻率亦往往與字頻和鄰群詞數目大小之間存在著共變的關係。因此於研究二中，設計了三個實驗來探討鄰群詞頻率是否亦會影響中文詞彙的辨識歷程。除了操弄詞頻和首字頻率外，並進一步控制平衡鄰群詞數目大小，以評估當目標詞有/無相對高頻鄰群詞之情況下，可能對詞彙判斷及詞彙唸名此二認知作業在反應時間的影響。結果發現，中文詞彙辨識歷程之中存在著抑制的鄰群詞頻率效果。整合這些結果，本論文亦企圖提出一個中文詞彙辨識歷程中可能蘊含的形似鄰群效果之認知運作機制。此外，研究一、二的各個實驗裡，比較兩種不同類型作業之間的詞頻效果量之大小，皆能明顯發現參與者於詞彙判斷作業的反應，表現出較大的詞頻效果量，這樣的結果顯示了中文在多字詞彙的辨識歷程之中亦涉及了次詞彙的字彙處理歷程，而非整詞的處理。

We manipulated the word frequency and the neighborhood size simultaneously in Study I, with the leading character frequency controlled, to explore their influences on word lexical decision and naming. The results showed a robust effect that words with a larger neighborhood size produced shorter reaction time than those with a smaller neighborhood size, irrespective of the word frequency and the tasks. This facilitative effect may occur due to a semantic network formed by neighbor words, resulting in the semantic activation to accelerate the word recognition. Additionally, different from alphabetic systems, neighborhood frequency in Chinese is usually confounded by component character frequency and neighborhood size. In Study II, three experiments were designed to explore the role of the neighborhood frequency effect in Chinese and the stimuli were all two-character words. This effect was evaluated on targets with- and without- higher frequency neighbors with neighborhood size matched. Among the experiments, the patterns of the leading character frequency effect and word frequency effect in the naming and lexical decision tasks were compared. The results implied an inhibitory neighborhood frequency effect in Chinese word recognition. Importantly, integrating these results of Study I and II, a possible cognitive mechanism of orthographic neighborhood effects was proposed in this thesis. Moreover, the comparison of the effect sizes of word frequency between the two different types of task showed that lexical decision responses demonstrated a larger word frequency effect, indicating that the sub-word processing was involved in the multi-character word recognition.