Permeable islands : A contrastive study of Swedish and English adjunct clause extractions

Abstract: This dissertation is concerned with extraction from adjunct clauses in Swedish and English. The topic is of interest because adjunct clauses are traditionally considered to be strong islands for extraction across languages (the Adjunct Condition). However, the purported universality of the island status of adjuncts has been challenged by claims that Swedish, Norwegian, and Danish allow extraction from adjuncts, raising questions concerning the permeability of such structures to dependency formation and the factors that may affect such permeability, and the possibility of variation between languages. To approach these issues I investigate factors that have been claimed to affect the acceptability of adjunct clause extraction sentences. Recent observations on English suggest that the acceptability of such extraction may be affected by the grammatical function of the extracted element (Tanaka 2015), the degree of syntactic integration of the adjunct clause (Haegeman 2004), the degree of semantic coherence between the adjunct and the matrix clause event (Truswell 2007, 2011; Tanaka 2015), and the finiteness of the adjunct clause (Manzini 1992; Truswell 2007, 2011). I present an acceptability judgment study showing that the first three factors are relevant to sentences involving extraction from adjunct clauses in Swedish as well. Two of the factors suggested to be relevant in English, viz. coherence and finiteness, are investigated more closely in two acceptability judgment experiments on native speakers of Swedish (Experiment 1) and English (Experiment 2), respectively, using sentences with extraction from temporal adjunct clauses. Evidence is presented that the acceptability of extraction sentences increases in the presence of a causal, coherent relation between the matrix and the adjunct clause in both Swedish and English, but that finiteness degrades sentences with extraction from coherent adjuncts only in English. The presence of a finiteness effect for English but not Swedish points to a possible factor of cross-linguistic variation, which I propose takes us one step further towards an account of the observed variation between English and the Mainland Scandinavian languages with regard to island sensitivity. The conclusion that coherence and finiteness affect the acceptability of adjunct clause extraction sentences also allows me to question claims that filler-gap association is suspended in island domains (e.g. Stowe 1986; Traxler & Pickering 1996; Omaki & Schulz 2011; Omaki et al. 2015), i.e. that processes whereby the extracted material (the filler) is associated with the position of the gap are not active in syntactic islands. In Experiment 3, I therefore use self-paced reading to investigate the real-time processing of extraction from temporal adjuncts in English. The results indicate that coherence and non-finiteness facilitate the processing of such structures at regions associated with gap integration, which speaks in favor of integrative processes related to dependency formation being active to some degree in adjunct clauses. The claim that syntactic islands are impermeable for integrative processes thus does not carry over to adjunct clauses of the kind investigated here. To the extent that adjunct clauses may be considered islands, the findings presented in this thesis thus suggest that the degree of acceptability of island violation sentences is dependent on multiple factors, and that languages may vary with regard to which factors affect the acceptability of island extraction sentences, which results in constrained and systematic instances of variation in the transparency of syntactic islands. It is furthermore hypothesized that certain adjunct clauses in Swedish and English might be a type of weak islands, and that this could explain the online permeability of adjunct clauses suggested by the results of Experiment 3.