Table_1_Syntactic structures in motion: investigating word order variations in verb-final (Korean) and verb-initial (Tongan) languages.DOCX

This study explored sentence processing in two typologically distinct languages: Korean, a verb-final language, and Tongan, a verb-initial language. The first experiment revealed that in Korean, sentences arranged in the scrambled OSV (Object, Subject, Verb) order were processed more slowly than those in the canonical SOV order, highlighting a scrambling effect. It also found that sentences with subject topicalization in the SOV order were processed as swiftly as those in the canonical form, whereas sentences with object topicalization in the OSV order were processed with speeds and accuracy comparable to scrambled sentences. However, since topicalization and scrambling in Korean use the same OSV order, independently distinguishing the effects of topicalization is challenging. In contrast, Tongan allows for a clear separation of word orders for topicalization and scrambling, facilitating an independent evaluation of topicalization effects. The second experiment, employing a maze task, confirmed that Tongan’s canonical VSO order was processed more efficiently than the VOS scrambled order, thereby verifying a scrambling effect. The third experiment investigated the effects of both scrambling and topicalization in Tongan, finding that the canonical VSO order was processed most efficiently in terms of speed and accuracy, unlike the VOS scrambled and SVO topicalized orders. Notably, the OVS object-topicalized order was processed as efficiently as the VSO canonical order, while the SVO subject-topicalized order was slower than VSO but faster than VOS. By independently assessing the effects of topicalization apart from scrambling, this study demonstrates that both subject and object topicalization in Tongan facilitate sentence processing, contradicting the predictions based on movement-based anticipation.

本研究探讨了两类类型学特征迥异的语言的句子加工机制：韩语（属于动词末尾型语言）与汤加语（属于动词起始型语言）。第一项实验结果显示，在韩语中，采用乱序OSV（宾语-主语-动词）语序的句子，其加工速度慢于规范SOV（主语-宾语-动词）语序的句子，凸显了乱序移位（scrambling）效应。同时发现，SOV句式中带主语话题化的加工速度与规范句式相当；而OSV句式中带宾语话题化的加工速度与准确率，均与乱序移位句式相近。不过，由于韩语中的话题化与乱序移位均采用相同的OSV语序，因此独立区分话题化的效应颇具挑战。与之形成鲜明对比的是，汤加语可清晰区分话题化与乱序移位的语序结构，从而能够独立评估话题化效应。第二项实验采用迷宫任务（maze task），证实汤加语的规范VSO（动词-主语-宾语）句式的加工效率高于乱序移位后的VOS（动词-宾语-主语）句式，由此验证了乱序移位效应。第三项实验考察了汤加语中乱序移位与话题化的双重效应，结果显示：从加工速度与准确率来看，规范VSO句式的加工效率最高，而乱序移位的VOS句式与带话题化的SVO（主语-宾语-动词）句式的加工效率均较低。值得注意的是，带宾语话题化的OVS（宾语-动词-主语）句式的加工效率与规范VSO句式相当；而带主语话题化的SVO句式的加工速度慢于VSO句式，但快于VOS句式。本研究通过独立分离乱序移位与话题化的效应，证实汤加语中的主语与宾语话题化均可促进句子加工，这与基于移位预期的理论预测相悖。