利用事件相關電位偵測語意一致性、曖昧及不一致之差異

本研究選用感性度、新奇性、現代感及複雜度的四個語意向度，嘗試運用語意差異法的平均數、標準差、偏態和峰度，分類不同語意距離的產品圖片。再透過事件相關腦電位（event-related potentials, ERPs），偵測不同語意距離的刺激物，包括：語意一致的、語意曖昧的和語意不一致的配對組合，並量測具有語意觸發效果的N400成分。結果顯示，「語意一致的」反應時間比「語意不一致的」還要快，而且「語意曖昧的」配對反應和「語意一致的」配對組合同樣快速，表示圖片特徵與對應的形容詞達到一致性的情境脈絡下，可以加速受測者辨識的速度；反之，圖片特徵與之不同，提高受測者的反應時間。此外，語意不一致的組合，在右後腦的部位發現N400效果；語意曖昧的組合僅在左後腦區出現微幅的N400效果；而語意一致的組合沒有出現N400效果。語意不一致和語意曖昧的組合雖皆出現N400效果，但兩者的語意處理機制在大腦中是不同的。語意不一致的N400效果是對刺激物前後脈絡的否定；而語意曖昧的N400效果則是在語意之間產生雙向的肯定。因此，在未來量測產品的曖昧語意上，腦波或許可作為設計研究的輔助量測工具。

The present study tried to detect semantic distances by Event-related Potentials (ERPs) The semantic distances of product images were classified into four dimensions- affectivity, novelty, modernity, and complexity by using mean, standard deviation, skewness, and kurtosis. In ERP test, the picture-word matches of various semantic distances in terms of congruence, ambiguity, and incongruence were used as stimuli for detecting N400 effects. The results showed that the reaction times of congruence were faster than those of incongruence. The reaction times of the congruence were the same as those of ambiguity. These findings suggested that the features of images with conformity context for the words could decrease the participants’ speed of identification. On the contrary, the differential features of images for the words could increase participants’ reaction times. Moreover, the shorter reaction time was noted to congruent stimuli, while ambiguous and congruent stimuli triggered equally fast responses. The incongruent combination elicited N400 responses in right posterior cerebrum; the ambiguous combination triggered only slightly N400 responses in left posterior cerebrum, while the congruent combination did not demonstrate N400 effects. The mechanism of N400 effects to the incongruent combinations is mainly denial to the stimuli in the context, while bilateral confirmation is involved in the reactions to the ambiguous combinations. Therefore, ERP may be applied in the future as an auxiliary tool to measure the semantic ambiguity in product design.