語言相對論：中文分類詞之事件相關腦電位研究

Abstract

語言相對論（linguistic relativity，又稱薩丕爾-沃夫假說，Sapir-Whorf hypothesis）主張語言結構會影響語言使用者的世界觀，不同語言的使用者也因此擁有不同的思考模式。語言相對論的相關文獻並未呈現一致的研究結果，而這樣的不一致可歸因於行為實驗研究方法的侷限性。即便是支持語言相對論的實證研究也常因使用行為實驗而備受詬病，因為那些“無趣老套”的實驗發現通常都是在有語言干擾─可能是語言的實驗刺激或是受試者的內在獨白（internal monologue）─的情況下產生（如Pinker 2007 [1994]）。Thierry (2016) 則建議，若要檢驗此假說，研究語言相對論的學者應該測量構基於無意識感知處理的自發大腦活動。 本研究旨在利用事件相關腦電位（event-related potentials，ERP）探討在不使用語言的情形下，中文母語者的視覺感知是否仍會受中文分類詞影響。受試者為中文母語者與英文母語者各十四名。實驗採用特異刺激典範（oddball paradigm），而受試者的作業則是在察覺目標刺激時按鍵。實驗刺激分成標準刺激（四種使用相同分類詞的物體照片，出現概率80%）、特異刺激（一種使用不同於標準刺激分類詞的物品照片，出現概率15%）與目標刺激（一張貓的照片，出現概率5%）。根據分類詞的分類，特異刺激與標準刺激的差異可能造成維度內違反（within-dimension deviant），或維度間違反（between-dimension deviant）。 實驗結果發現，與標準刺激相比，只有中文母語者的維度內違反特異刺激誘發了顯著的P2效應（150-250 ms），顯示出分類詞影響了中文母語者的物體概念分類與感知。本研究結果異於前人的相關研究，因前人多以語言作為實驗刺激，且發現分類詞的影響只存在於非快速的（unspeeded）實驗作業中（Huang& Chen 2014; Imai & Saalbach 2010; Saalbach & Imai 2007）。 雖然分類詞的效果非常精細，但這樣的效果揭示了在沒有語言信息與語言處理的情況下，語言仍影響著其他非語言的認知功能。 Linguistic relativity, also known as Sapir-Whorf hypothesis, upholds that the structure of a language influences its speakers’ worldview and speakers of different languages might therefore think differently. Research on linguistic relativity has obtained inconsistent results, which might be due to the methodological limitation of behavioral studies. Moreover, if adopting behavioralmethods, empirical studies yielding positive results were usually castigated for showing ‘banal’ findings resulting from the contamination of explicit verbal cues or inevitable internal monologue during the experimental tasks (e.g., Pinker 2007 [1994]). As suggested by Thierry (2016), relativists are encouraged to test the hypothesis by measuring spontaneous brain activities underlying the unconscious perceptual processes. Using the event-related potentials (ERP) technique, this study aimed to explore whether Mandarin Chinese speakers’ visual perception would be modulated by the Mandarin classifier system. Fourteen native speakers of Chinese (CS) and fourteen native speakers of English (ES) participated in the experiment. Participants were instructed to look attentively at the stimuli and to perform a target detection task in an oddball paradigm. The standard stimuli (probability 80%) were photos of four (repeated) objects sharing the same classifier, and the deviant stimuli (probability 15%) were photos of one object not categorized by the standards’ classifier, which were either dimensionally congruent (within-dimension deviant) or dimensionally incongruent (between-dimension deviant) with the standards in terms of classifier categories. The targets were photos of a cat (probability 5%). The results revealed that when compared with standards, within-dimension deviants induced a significant P2 effect (150-250 ms) only in the Chinese group, suggesting that classifiers affected Chinese speakers’ object conceptual categorization and perception. Our findings were qualitatively different from previous research on classifier relativity where classifier effects only appeared in unspeeded tasks with verbal cues (Huang& Chen 2014; Imai & Saalbach 2010; Saalbach & Imai 2007). Although the classifier effect was intricate, it demonstrated that language affects non-verbal cognitive systems, even when linguistic processing is not needed.