Search

In the research field of sentence processing, many researchers have reported experimental results that support the hypothesis of incremental processing, even in a head final-language like Japanese, similar to head-initial languages like English. This study examined the effect of negative concord adverbs (NCAs) in temporarily locating the left clause boundaries of complex sentences. The experiment results showed that the sentence processor preferentially establishes the dependency between the negative concord adverb and negative suffix over the dependency between the argument and its predicate. Moreover, to construct the NCA-suffix relationship, the sentence processor could discard the argument-predicate relationship that has been established before, and could change the location of the left clause boundary.

Recently a growing number of studies have found that a specific type of semantic/thematic anomaly would elicit a P600 effect, which has been considered as an index of syntactic-processing difficulty, suggesting (i) that there exists a semantic-processing stream which operates independently from syntactic-processing stream and (ii) that the output of semantic processing stream can, at least under certain circumstances, challenge the output from syntactic-processing stream and (iii) that the conflict between those outputs results in a so-called “Semantic P600” effect. The present study, however, points out that Semantic P600 effects can be task-relevant components and examined whether a Semantic P600 effect would be elicited even when participants are not asked to do a secondary task like plausibility judgment task. We recorded event-related brain potentials (ERPs) when participants passively read semantically/thematically-reversible Japanese sentences (e.g., literal translation: the leaves of eucalypts-NOM the koala on a tree-ACC took-a-bite-into) in the absence of a plausibility judgment task. We found a larger N400 effect but no P600 enhancement in response to the target words. We argue (i) that the plausibility-judgment task might motivate readers to actively anticipate how the incoming sentence will develop and (ii) that the P600 effects observed in the previous studies might reflect the processing load associated with reanalysis processes resulted from the mismatch between the tentative thematic-role assigned to the argument(s) and the argument structure of the verb which was actually encountered. We conclude that the so-called Semantic P600 effects are task relevant and that they cannot be the evidence for the existence of semantic-processing stream.

本研究では、主節主語の種類と主語-動詞間の距離を操作した読文実験を実施した。その結果、NPだけ-動詞の統合では距離の効果が見られたが、NPだけが-動詞の統合では距離の効果が見られなかった。この結果は、主節主語と埋め込み節主語の類似性が高い場合、埋め込み節主語-動詞の統合の際に、主節主語が一時的にアクセスされ、主節主語の活性度を高めているために距離の効果が見られなくなるという仮説を支持するものである。

ここ10 年の日本語文処理研究において、しばしば取り上げられてきた話題の一つに、「主語関係節（SR）と目的語関係節（OR）の処理負荷の大小とその原因」がある。そこで行われてきた議論の中心は、主語関係節（[ gap 議員を非難した] 記者）よりも、目的語関係節（[議員が gap 非難した] 記者）のほうが主要部名詞（HN）と空所（gap）との間の構造上の距離が長いために、その処理負荷が大きくなるというものであった。本研究では、OR の困難さの原因として、HN とgap 間の構造上の距離以外に、関係節構造を含む記号列であること、およびその関係節構造の種類が何であるかの2 つに関わる予測可能性が関わっている可能性を指摘する。そして、それらの要因を統制した場合にはOR のほうが読み時間が短くなるという事実を提示する。

本研究は、事象関連電位を用いて、韓国語の主語関係節と目的語関係節の処理過程を検討した。実験の結果、主語関係節に対してLAN及びP600効果が観察された。この結果は、目的語関係節の方が処理負荷が低いことを示し、gapとfillerの統合負荷が、線形的距離によって決まるという仮説とより整合性がある。

Most languages have lexical items that need to be licensed by a negation marker. These lexical items are termed negative polarity items (NPIs). This study investigated how NPI licensing is achieved in on-line sentence processing, by analyzing event-related brain potentials (ERPs). In an experimenter-paced reading experiment, ERPs were recorded while participants read sentences containing the NPI shika and the negation marker nai (i.e., the shika-nai construction). The results showed that both the N400 and P600 components were elicited for sentences with a deviant shika-nai construction, compared to normal counterparts. This indicates that the license of shika calls for both semantic and syntactic processing. Furthermore, it is argued, on the basis of a comparison of the results of the present study and those of Saddy et al.'s (2004) ERP study on German, that the semantic stage is universally required in the processing of NPI licensing.